Patent Publication Number: US-2021188261-A1

Title: Camera system for intelligent driver assistance system, and driver assistance system and method

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a Continuation-In-Part Application of U.S. application Ser. No. 16/730,353, filed Dec. 30, 2019, which is a Continuation Application of U.S. application Ser. No. 16/512,887, filed Jul. 16, 2019, which is a Continuation Application of U.S. application Ser. No. 16/218,170, filed Dec. 12, 2018, which claims the benefit of International Application No. PCT/KR2018/000826, filed on Jan. 18, 2018, which claims the benefit of Korean Application No. KR 10-2017-0009172, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009173, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009174, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009175, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009176, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009209, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009210, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009211, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009212, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009213, filed Jan. 19, 2017, Korean Application No. KR 10-2017-0009214, filed Jan. 19, 2017, and Korean Application No. KR 10-2017-0009215, filed Jan. 19, 2017, the disclosures of which are incorporated by reference in their entireties. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to an advanced driving assistance system (ADAS), and more particularly, to a camera system for an ADAS, and a driver assistance system and method. 
     BACKGROUND ART 
     An ADAS, which is a enhanced driver assistance system for assisting a driver in driving a vehicle, is configured to sense a situation ahead, determine a situation on the basis of the sensed result, and control the vehicle&#39;s behavior on the basis of the situation determination. For example, an ADAS sensor apparatus senses vehicles ahead and recognizes lanes. Subsequently, when a target lane or a target speed and a target ahead are determined, an electrical stability control (ESC), an engine management system (EMS), a motor driven power steering (MDPS), and the like of a vehicle are controlled. Typically, an ADAS may be implemented with an automatic parking system, a low-speed city driving assistance system, a blind zone warning system, and the like. 
     In the ADAS, a sensor apparatus for sensing a situation ahead includes a Global Positioning System (GPS) sensor, a laser scanner, a front radar, a Lidar, etc. Typically, the sensor apparatus is a front-view camera for capturing a region ahead of the vehicle. 
     DETAILED DESCRIPTION 
     Technical Problem 
     A first embodiment of the present disclosure is directed to providing a voltage logic and a memory logic that may be used in a front-view camera system for an ADAS. 
     Also, the first embodiment of the present disclosure is directed to providing a method of coupling a lens barrel and a lens holder in a front-view camera system for an ADAS. 
     A third embodiment of the present disclosure is directed to providing a collision prevention system and method capable of avoiding colliding with a target vehicle by controlling the steering of a host vehicle. 
     Also, the third embodiment of the present disclosure is directed to providing a collision prevention system and method capable of avoiding colliding with a target vehicle by controlling the speed of a host vehicle. 
     Also, the third embodiment of the present disclosure is directed to providing a collision prevention system and method capable of avoiding colliding between a host vehicle and a vehicle cutting ahead of the host vehicle from the next lane by controlling one or more of the speed, the braking, and the steering of the host vehicle when the cutting vehicle changes lanes. 
     A technical object of a fourth embodiment of the present disclosure is to provide a driving assistance system for making a lane change to a left turn lane in order to turn left. 
     A technical object of the fourth embodiment of the present disclosure is to provide a driving assistance system for a vehicle turning left by controlling the steering of the vehicle after the vehicle enters a left turn lane. 
     Also, a fifth embodiment of the present disclosure is directed to providing an emergency braking system and method capable of controlling an emergency braking start time according to a degree to which a road is slippery. 
     Also, the fifth embodiment of the present disclosure is directed to providing an emergency braking system and method capable of advancing an emergency braking start time when it is determined that a vehicle is running on a slippery road. 
     A technical object of a sixth embodiment of the present disclosure is to provide a driving assistance system for preventing a collision with a vehicle cutting ahead of a host vehicle. 
     A seventh embodiment of the present disclosure is directed to providing a cross traffic alert (CTA) system and method capable of sensing a risk of collision between a host vehicle and a nearby vehicle at an intersection and warning a driver of the collision risk according to the level of the collision risk. 
     The seventh embodiment of the present disclosure is directed to providing a CTA system and method capable of sensing a risk of collision between a host vehicle and a nearby vehicle at an intersection and capable of performing steering control on the host vehicle as well as warning a driver of the collision risk according to the level of the collision risk. 
     An eighth embodiment of the present disclosure is directed to implementing automatic emergency braking on the basis of a longitudinal time-to-collision (TTC) and a lateral TTC between a host vehicle and a third-party vehicle in a front-view camera system for an ADAS. 
     A technical object of an ninth embodiment of the present disclosure is to provide a driving assistance system for determining a possibility of a collision between a host vehicle and a nearby vehicle and warning a driver of the collision possibility. 
     A technical object of a tenth embodiment of the present disclosure is to provide a driving assistance system for determining a TTC between vehicles at an intersection and prevent a collision between the vehicles. 
     Also, an eleventh embodiment of the present disclosure is directed to providing an intersection prevention system and method capable of determining priorities for Cross traffic alert (CTA) control through communication between a host vehicle and nearby vehicles when the host vehicle enters an intersection and of enabling a plurality of vehicles to systematically perform CTA control at the intersection according to the determined CTA priorities. 
     Also, the eleventh embodiment of the present disclosure is directed to providing a CTA system and method capable of detecting a laterally appearing vehicle or pedestrian and then performing CTA control to prevent a collision therebetween when a host vehicle enters an intersection. 
     A twelfth embodiment of the present disclosure is directed to providing a vehicle control apparatus and method capable of sensing an intersection by means of a radar and a camera disposed in a host vehicle, sensing a side of the host vehicle at the sensed intersection, and determining whether the host vehicle will collide with a target vehicle. 
     Also, the twelfth embodiment of the present disclosure is directed to providing a vehicle control apparatus and method capable of issuing a warning to a driver and performing emergency braking on a host vehicle when it is determined that there is a possibility of a collision between the host vehicle and a target vehicle on the basis of whether the host vehicle will collide with the target vehicle. 
     A technical object of a thirteenth embodiment of the present disclosure is to provide a diving assistance system capable of using a camera system to watch a direction, other than a direction that a driver is watching, and thus controlling a vehicle. 
     Technical Solution 
     According to the first embodiment of the present disclosure, there is disclosed a vehicle camera system including a lens ( 10 ) configured to capture a region ahead of a vehicle; a lens barrel ( 15 ) configured to accommodate the lens in an internal space thereof; a lens holder ( 20 ) coupled to the lens barrel; an image sensor ( 31 ) configured to sense an image captured by the lens; an image processor ( 41 ) configured to receive image data from the image sensor and process the received image data; and a camera micro-control unit (MCU) ( 42 ) configured to communicate with the image processor and receive the data processed by the image processor. 
     The vehicle camera system further includes a first converter unit ( 521 ) configured to receive an ignition voltage ( 510 ) and output at least one voltage; and a regulator unit ( 523 ) configured to receive the voltage output by the first converter unit ( 521 ) and output at least one voltage. 
     The camera MCU ( 42 ) receives a first voltage ( 511 ) from the first converter unit  521  as operating power, and the image processor ( 41 ) receives the first voltage ( 511 ) from the first converter unit ( 521 ) as operating power. 
     The first voltage ( 511 ) output from the first converter unit ( 521 ) is 3.3 V. 
     The image processor ( 41 ) receives a second voltage ( 512 ) from the first converter unit ( 521 ), the image sensor ( 31 ) receives a fifth voltage ( 515 ) from the regulator unit ( 523 ), and the second voltage ( 512 ) is the same as the fifth voltage ( 515 ). 
     The second voltage and the fifth voltage ( 515 ) are 1.8 V. 
     The image sensor ( 31 ) receives a sixth voltage ( 516 ) from the regulator unit ( 523 ) as core power, and the sixth voltage ( 516 ) is 2.8 V. 
     The first converter unit ( 521 ) is configured to include at least one DC-to-DC converter, and the regulator unit ( 523 ) is configured to include at least one low-dropout (LDO). 
     The camera MCU ( 42 ) communicates with a first memory ( 531 ). 
     The image processor ( 41 ) communicates with a second memory ( 532 ) and a third memory ( 533 ). 
     The second memory ( 532 ) has capacity determined depending on the number of advanced driving assistance system (ADAS) functions supported by the vehicle camera system. 
     The vehicle camera system is used to implement at least one of the following functions: Road Boundary Departure Prevention Systems (RBDPS), Cooperative Adaptive Cruise Control Systems (CACC), Vehicle/roadway warning systems, Partially Automated Parking Systems (PAPS), Partially Automated Lane Change Systems (PALS), Cooperative Forward Vehicle Emergency Brake Warning Systems (C-FVBWS), Lane Departure Warning Systems (LDWS), Pedestrian Detection and Collision Mitigation Systems (PDCMS), Curve Speed Warning Systems (CSWS), Lane Keeping Assistance Systems (LKAS), Adaptive Cruise Control systems (ACC), Forward Vehicle Collision Warning Systems (FVCWS), Manoeuvring Aids for Low Speed Operation systems (MALSO), Lane Change Decision Aid Systems (LCDAS), Low Speed Following systems (LSF), Full Speed Range Adaptive cruise control systems (FSRA), Forward Vehicle Collision Mitigation Systems (FVCMS), Extended Range Backing Aids systems (ERBA), Cooperative Intersection Signal Information and Violation Warning Systems (CIWS), and Traffic Impediment Warning Systems (TIWS). 
     The lens barrel additionally has a flange, and a groove is formed on a lower surface of the flange of the lens barrel. 
     The groove is formed to have at least one of a single circular shape, a dual circular shape, a cross lattice shape, and a zigzag shape. 
     A groove is formed on an upper surface of the lens holder. 
     The groove is formed to have at least one of a single circular shape, a dual circular shape, a cross lattice shape, and a zigzag shape. 
     A collision prevention system according to a third embodiment of the present disclosure includes a camera system configured to generate image data regarding regions ahead of, behind, to the left of, and to the right of a host vehicle, a radar system configured to generate radar data regarding objects ahead of, behind, to the left of, and to the right of the host vehicle, and an electronic control unit (ECU) configured to analyze the image data and the radar data, detect a target vehicle from among nearby vehicles, and control at least one of the speed, braking, and steering of the host vehicle when it is determined that a collision will occur between the host vehicle and the target vehicle is determined. 
     When it is determined that a collision will occur between the host vehicle and the target vehicle is determined, the ECU transmits a control signal to at least one of a vehicle posture controller, a steering controller, an engine controller, a suspension controller, and a brake controller, which are disposed in the host vehicle. 
     It is assumed that a collision with a target vehicle ahead is expected to occur. When there is no risk of collision with a vehicle traveling in the next lane, the ECU controls the steering controller to change a traveling direction of the host vehicle. On the other hand, when there is a risk of collision with a vehicle traveling in the next lane, the ECU controls the engine controller and the brake controller. 
     When a collision with a target vehicle cutting from the next lane is expected to occur, the ECU controls the steering controller to change the traveling direction of the host vehicle, or controls the engine controller and the brake controller to control the speed of the host vehicle. 
     A collision prevention method according to the third embodiment of the present disclosure includes generating image data regarding regions ahead of, behind, to the left of, and to the right of a host vehicle and generating radar data regarding objects ahead of, behind, to the left of, and to the right of the host vehicle; analyzing the image data and the radar data to detect a target vehicle from among nearby vehicles; determining whether a collision will occur between the host vehicle and the target vehicle; and controlling at least one of the speed, braking, and steering of the host vehicle when it is determined that a collision will occur. 
     Also, when there is no risk of collision with a vehicle traveling in the next lane, the steering is controlled to change the traveling direction of the host vehicle. On the other hand, when there is a risk of collision with a vehicle traveling in the next lane, the speed of the host vehicle is controlled. 
     Also, when a collision with a target vehicle cutting from the next lane is expected to occur, the steering is controlled to change the traveling direction of the host vehicle, or the speed of the host vehicle is controlled. 
     A driving assistance system according to a fourth embodiment of the present disclosure is provided. The driving assistance system includes a camera system. The vehicle camera system includes an ECU for controlling the vehicle through state information of the surroundings of the vehicle. The ECU receives the state information and controls the steering of the vehicle such that the lane of the steering is changed to a left-turn lane. 
     According to the fourth embodiment, the state information includes at lest one of a road mark and an expanded branch lane. 
     According to the fourth embodiment, the camera system discovers first information regarding a region ahead of the vehicle, and the ECU receives the first information and controls the speed and brake of the vehicle. 
     According to the fourth embodiment, the first information includes at least one of data regarding vehicles ahead, data regarding lanes ahead, distances from font vehicles, data regarding traffic signs of an intersection, and signal data of an intersection. 
     According to the fourth embodiment, after the vehicle is steered to the left-turn lane, the ECU determines and controls whether to stop the vehicle through the second information regarding a region surrounding the vehicle, which is received from the vehicle camera system. Also, the second information includes an intersection stop line, the presence of vehicles ahead, and intersection signal data. 
     According to the fourth embodiment, the ECU controls the driver warning controller to inform the driver of whether the vehicle is allowed to turn left, which is determined through the state information. 
     According to the fourth embodiment, the driving assistance system further includes a GPS apparatus for informing of whether a left turn is allowed at the intersection and whether there is a left-turn branch lane ahead. The ECU receives and processes data transmitted by the GPS apparatus. 
     An emergency braking system according to a fifth embodiment of the present disclosure includes a camera system configured to recognize a road condition or a traffic sign ahead, a navigation processor configured to calculate the speed of a host vehicle and calculate a relative speed between the host vehicle and a target vehicle, and an ECU configured to calculate a time-to-collision on the basis of the relative speed, calculate a start time of emergency braking control, and advance the start time of emergency braking control when it is determined that the host vehicle is traveling on a slippery road. 
     The emergency braking system according to the fifth embodiment of the present disclosure further includes a navigation system configured to recognize weather information corresponding to the road on which the vehicle is traveling, and the ECU advances the start time of emergency braking control when it is determined that the road is slippery on the basis of the weather information corresponding to the road. 
     When a windshield wiper operates for a certain period of time, the ECU of the emergency braking system according to the fifth embodiment of the present disclosure determines that the host vehicle is traveling on a slippery road and advances the start time of emergency braking control. 
     The ECU of the emergency braking system according to the fifth embodiment of the present disclosure applies a weight of 30% to 70% when the start point of emergency braking control is calculated, and advances the start time of emergency braking control. 
     A driving assistance system according to a sixth embodiment of the present disclosure is provided. The driving assistance system further includes an ECU configured to determine a risk of collision with a third-party vehicle on the basis of the location of the host vehicle in a first lane in which the host vehicle is traveling and configured to control the host vehicle. The camera system discovers the presence and location of a third-party vehicle cutting ahead of the host vehicle, and the ECU controls the host vehicle on the basis of the lateral locations of the host vehicle and the third-party vehicle. 
     According to the sixth embodiment, when the camera system determines that no vehicle is present in a second lane, which is opposite to a lane from which the third-party vehicle is cutting into the first lane, the ECU controls the steering of the host vehicle to make a lane change to the second lane. 
     According to the sixth embodiment, when the camera system determines that another vehicle is present in the lane opposite to the lane from which the third-party vehicle is cutting ahead of the host vehicle, the ECU changes the speed of the host vehicle while controlling the host vehicle to maintain the first lane. 
     According to the sixth embodiment, the driving assistance system further includes a radar apparatus configured to discover a distance between the host vehicle and the third-party vehicle, and the camera system finds the lateral positions of the host vehicle and the third-party vehicle. 
     According to the sixth embodiment, the ECU controls the host vehicle to accelerate in order to pass the third-party vehicle before the third-party enters the first lane. 
     According to the sixth embodiment, the ECU controls the host vehicle to decelerate in order to prevent a collision with the third-part vehicle. 
     According to the sixth embodiment, the driving assistance system further includes a radar apparatus configured to discover a longitudinal distance between the host vehicle and the third-party vehicle. The camera system discovers a lateral distance between the host vehicle and the third-party vehicle, and the ECU performs longitudinal and lateral control on the host vehicle in order to prevent a collision between the host vehicle and the third-party vehicle. 
     According to the sixth embodiment, the camera system discovers the first lane ahead of the host vehicle, and the ECU calculates the location of the host vehicle in the first lane through first lane information acquired by the camera system and controls the steering and speed of the host vehicle. 
     A cross traffic alert (CTA) system according to a seventh embodiment of the present disclosure includes an ECU configured to determine, on a level basis, a risk of collision with a nearby vehicle on the basis of whether the steering wheel is operated at an intersection and whether the host vehicle is stopped or is traveling at the intersection and a driver warning controller configured to warn about the risk of collision between the host vehicle and the nearby vehicle in a video and/or audio manner on the basis of a result of the ECU determining the risk of collision. 
     When the steering wheel is operated to turn left, right, or around while the host vehicle is stopped, the ECU determines a first-level risk of collision between the host vehicle and the nearby vehicle. For the first-level collision risk, the driver warning controller issues a warning about the first-level collision risk in the video manner. 
     When the steering wheel is operated to turn left, right, or around while the host vehicle starts traveling, the ECU determines a second-level risk of collision between the host vehicle and the nearby vehicle. For the second-level collision risk, the driver warning controller issues a warning about the second-level collision risk in both of the video manner and the audio manner. 
     The CTA system includes a steering controller configured to perform control on an electronic power steering system (MPDS) for driving the steering wheel. Also, when there is a risk of collision with the nearby vehicle but the steering wheel is not operated to avoid the collision while the host vehicle is turning left, right, or around, the ECU determines a third-level collision risk. For the third-level collision risk, the driver warning controller issues a warning about the third-level collision risk in both of the video manner and the audio manner. For the third-level collision risk, the steering controller controls the steering to avoid the collision between the host vehicle and the nearby vehicle. 
     An image processor according to an eighth embodiment of the present disclosure is configured to calculate a longitudinal TTC (TTCx) and a lateral TTC (TTCy) between a host vehicle and a third-party vehicle ahead and determine whether to execute autonomous emergency braking (AEB) on the basis of a relationship between the longitudinal TTC and the lateral TTC. 
     In order to determine whether to execute the AEB, the image processor determines to execute the AEB when the absolute value of the difference between the longitudinal TTC and the lateral TTC is smaller than a predetermined threshold TTCth. 
     The pre-determined threshold is determined on the basis of at least one of the longitudinal TTC, the lateral TTC, a road condition, a road inclination, and a temperature. 
     A driving assistance system according to an ninth embodiment of the present disclosure is provided. The driving assistance system includes a camera system and also includes an ECU configured to determine a risk of collision with a nearby vehicle on the basis of the state of a host vehicle at an intersection, a rear radar installed in the host vehicle and configured to recognize the nearby vehicle, and a driver warning controller configured to issue a warning about the risk of collision between the host vehicle and the nearby vehicle on the basis of a result of the ECU determining the risk of collision. The camera system recognizes the signal of a traffic light ahead of the host vehicle and transmits the signal to the ECU. 
     According to the ninth embodiment, the camera system recognizes that the traffic light is changed from a “go” signal to a yellow signal or a red signal. 
     According to the ninth embodiment, the ECU calculates the presence of the nearby vehicle, a distance from the nearby vehicle, the speed of the nearby vehicle, and the traveling angle of the nearby vehicle by using the data measured by the rear radar, and determines the risk of collision with the nearby vehicle. 
     According to the ninth embodiment, when the “go” signal of the traffic light is changed to the yellow signal or red signal and the rear radar recognizes that the nearby vehicle accelerates or travels at constant speed, the ECU warns a driver of the collision risk through the driver warning controller. 
     According to the ninth embodiment, the driver warning controller warns the driver in at least one of a video manner, an audio manner, and steering wheel vibration. 
     According to the tenth embodiment, a driving assistance system including a camera system includes an ECU configured to determine a risk of collision with a nearby vehicle on the basis of a traveling path of a host vehicle at an intersection and configured to control a vehicle and a sensor configured to discover the nearby vehicle at the intersection. The nearby vehicle travels in a direction crossing the traveling direction of the host vehicle, and the ECU calculates a time-to-collision through the speed of the host vehicle and the speed of the nearby vehicle. 
     According to the tenth embodiment, the camera system measures the location of the nearby vehicle. The sensor measures a distance between the host vehicle and the nearby vehicle, and the ECU calculates a time-to-collision through the data measured by the camera system and the sensor. 
     According to the tenth embodiment, the ECU calculates a first time-to-collision of the host vehicle and the nearby vehicle in combination of a traveling route and the data measured by the camera system and the sensor, re-calculates a possibility of collision between the host vehicle and the nearby vehicle after the first time-to-collision, and calculates a vehicle control start time for calculating a second time-to-collision. When the second time-to-collision is smaller than the first time-to-collision at the vehicle control start time, the ECU controls the host vehicle. 
     According to the tenth embodiment, the vehicle control start time includes a first vehicle control start time and a second vehicle control start time later than the first vehicle control start time. The ECU generates an alert at the first vehicle control start time and then warns the driver, and controls the steering and braking of the vehicle at the second vehicle control start time to avoid a collision. 
     A CTA system according to an eleventh embodiment of the present disclosure a camera system configured to generate image data regarding regions ahead of, behind, to the left of, and to the right of a host vehicle, a radar system configured to generate radar data regarding regions ahead of, behind, to the left of, and to the right of the host vehicle, and an ECU configured to analyze the image data and the radar data when the host vehicle enters an intersection, determine whether a collision will occur between the host vehicle and nearby vehicles or pedestrians, and set a priority of CTA control for the host vehicle and the nearby vehicles when it is determined that a collision will occur. 
     When it is determined that a collision will occur at the intersection, the ECU transmits a control signal to at least one of a vehicle posture controller, a steering controller, an engine controller, a suspension controller, and a brake controller, which are disposed in the host vehicle. 
     Also, when it is determined that a collision will occur at the intersection, the ECU generates a CTA control signal of the host vehicle and transmits the CTA signal to the nearby vehicles. Also, the ECU receives CTA control signals of the nearby vehicles from the nearby vehicles and compares the CTA control signal of the host vehicle and the CTA control signals of the nearby vehicles to set a priority for the CTA control. 
     A vehicle control apparatus according to a twelfth embodiment of the present disclosure includes an image generation unit configured to capture a region ahead of a host vehicle to generate an image regarding the region ahead, a first information generation unit configured to sense the region ahead of the host vehicle and generate first sensing information, a second information generation unit configured to sense the side of the host vehicle and increase the sensing of the side of the host vehicle to generate second sensing information when an intersection is sensed on the basis of the first sensing information and the image regarding the region ahead, and a control unit configure to select a target vehicle on the basis of the second information, determine whether the target vehicle will collide with the host vehicle, and control the braking of the host vehicle. 
     Here, the second information generation unit generates the second sensing information by increasing the width of the sensing region to the side of the host vehicle after the intersection is sensed over the area of the sensing region to the side of the host vehicle before the intersection is sensed. 
     Also, the second information generation unit generates the second sensing information by increasing the length of the sensing region to the side of the host vehicle after the intersection is sensed over the length of the sensing region to the side of the host vehicle before the intersection is sensed. 
     Also, the second information generation unit generates the second sensing information for increasing the number of times a vehicle is sensed for a certain period of time by decreasing a sensing cycle in which sensing is performed in the sensing region to the side of the host vehicle after the intersection is sensed below a sensing cycle in which sensing is performed in the sensing region to the side of the host vehicle before the intersection is sensed. 
     Also, based on the second sensing information, the control unit selects a vehicle close to the host vehicle and a vehicle approaching the host vehicle as target vehicles. 
     Also, the control unit determines whether a collision will occur between the host vehicle and a target vehicle, and performs control to warn a driver of the collision or to brake the host vehicle when it is determined that the collision will occur between the host vehicle and the target vehicle. 
     A vehicle control method according to the twelfth embodiment of the present disclosure includes capturing and sensing a region ahead of a host vehicle to sense lanes; increasing the sensing of a side of the host vehicle, choosing the side of the host vehicle as a critical sensing target, and intensively sensing the side of the vehicle when the intersection is sensed; and selecting a target vehicle on the basis of the sensing result, determining whether a collision will occur between the target vehicle and the host vehicle, and controlling the host vehicle. 
     Here, the sensing of the side of the host vehicle includes increasing the width of the sensing region to the side of the host vehicle after the intersection is sensed over the width of the sensing region to the side of the host vehicle before the intersection is sensed. 
     Also, the sensing of the side of the host vehicle includes increasing the length of the sensing region to the side of the host vehicle after the intersection is sensed over the length of the sensing region to the side of the host vehicle before the intersection is sensed. 
     Also, the sensing of the side of the host vehicle includes increasing the number of times sensing is performed for a certain period of time by decreasing a sensing cycle in which sensing is performed in the sensing region to the side of the host vehicle after the intersection is sensed below a sensing cycle in which sensing is performed in the sensing region to the side of the host vehicle before the intersection is sensed. 
     Also, the controlling of the host vehicle includes selecting a vehicle close to the host vehicle and a vehicle approaching the host vehicle as target vehicles on the basis of the sensing result. 
     Also, the controlling of the host vehicle includes determining whether a collision will occur between the host vehicle and a target vehicle, and performing control to warn a driver of the collision or to brake the host vehicle when it is determined that the collision will occur between the host vehicle and the target vehicle. 
     A driving assistance system according to a thirteenth embodiment of the present disclosure is provided. The driving assistance system includes a camera system and further includes an ECU configured to determine a risk of collision with a nearby vehicle at an intersection on the basis of a traveling route of a host vehicle and a driver monitoring camera configured to sensing a first direction that a driver is watching at the intersection. The ECU controls the vehicle camera system to sense a second direction, which is different from the first direction. 
     According to a thirteenth embodiment, when the vehicle camera system senses an object approaching the host vehicle from the second direction, the ECU generates a warning. 
     According to the thirteenth embodiment, when there is a possibility of collision between the host vehicle and an object located in the second direction, the ECU controls both or either of the steering and braking of the host vehicle. 
     According to the thirteenth embodiment, the driver monitoring camera senses a heading direction of the driver&#39;s face or a viewing direction of the driver&#39;s eyes to sense a direction that the driver is watching. 
     According to the thirteenth embodiment, the first direction is a driver control range, and the second direction is a system control range. The ECU generates an alert when there is a collision possibility in the driver control range, and generates an alert and controls both or either of the steering and braking of the host vehicle when there is a collision possibility in the system control range. 
     According to the thirteenth embodiment, the ECU determines, on a level basis, a collision risk possibility on the basis of a distance from a third-party vehicle that is collidable with the host vehicle. When a collision risk level in the system control range is the same as that in the driver control range, the ECU determines that the collision risk possibility in the system control range is higher than that in the driver control range. 
     Advantageous Effects 
     According to the first embodiment of the present disclosure, a voltage logic and a memory logic that may be used in a front-view camera system for an ADAS may be implemented. 
     Also, according to the first embodiment of the present disclosure, a scheme capable of coupling a lens barrel and a lens holder in a front-view camera system for an ADAS may be provided. 
     Also, according to the third embodiment of the present disclosure, a scheme capable of coupling a lens barrel and a lens holder in a front-view camera system for an ADAS may be provided. 
     Also, according to the third embodiment of the present disclosure, it is possible to avoid a collision with a target vehicle by controlling the steering of a host vehicle. 
     Also, according to the third embodiment of the present disclosure, it is possible to avoid a collision with a target vehicle by controlling the speed of a host vehicle. 
     Also, according to the third embodiment of the present disclosure, it is possible to avoid a collision between a host vehicle and a vehicle cutting from the next lane by controlling one or more of the speed, braking, and steering of the host vehicle when the vehicle in the next lane changes lanes. 
     According to the fourth embodiment of the present disclosure, it is possible to control a vehicle traveling in a left-hand lane to automatically enter a branch lane using state information acquired through a camera system. 
     According to the fourth embodiment of the present disclosure, it is possible to reduce a possibility of collision with another vehicle through first information and second information acquired by a camera system when a vehicle enters a branch lane. 
     According to the fourth embodiment of the present disclosure, it is possible to determine whether a left turn is allowed through second information acquired by a camera system after a vehicle enters a branch lane, and thus to control the steering of the vehicle. 
     Also, according to the fifth embodiment of the present disclosure, it is possible to control a start time of emergency braking according to a degree to which a road is slippery. 
     Also, according to the fifth embodiment of the present disclosure, it is possible to prevent a head-on/rear-end collision accident due to the increase in braking distance by advancing the emergency braking start time when it is determined that the road is slippery. 
     According to the sixth embodiment of the present disclosure, by sensing a third-party vehicle cutting ahead of a host vehicle through a camera system for sensing a region ahead of the host vehicle, it is possible to prevent a collision between the host vehicle and the third-party vehicle. 
     According to the sixth embodiment of the present disclosure, a lane ahead of a host vehicle and also sense a third-party vehicle cutting ahead of the host vehicle may be sensed, and the location of the host vehicle in the lane may be determined. Through such information, it is possible to prevent a collision between the host vehicle and the third-party vehicle through the deceleration, acceleration, and steering control of the host vehicle. 
     With the CTA system and method according to the seventh embodiment of the present disclosure, a risk of collision between a host vehicle and a nearby vehicle may be sensed, and a driver may be warned of the collision risk according to the level of the collision risk. Also, by controlling the steering of the host vehicle as well as issuing the warning for the collision risk according to the level of the collision risk, it is possible to avoid the collision. 
     According to the eighth embodiment of the present disclosure, autonomous emergency braking may be implemented on the basis of la longitudinal TTC and a lateral TTC between a host vehicle and a third-party vehicle in a front-view camera system for an ADAS. 
     According to the ninth embodiment of the present disclosure, data regarding an ambient situation of a host vehicle may be acquired through a camera system and a rear radar, and the ECU may determine a risk of collision between the host vehicle and a nearby vehicle. 
     According to the ninth embodiment of the present disclosure, when it is determined that there is a possibility of collision between the host vehicle and the nearby vehicle, the ECU may warn a driver of the collision to avoid the collision. Thus, it is possible to prevent an accident that may occur when an intersection is entered. 
     According to a tenth embodiment of the present disclosure, a time-to-collision of a host vehicle and a nearby vehicle may be calculated, and the steering and braking of the host vehicle may be controlled on the basis of the time-to-collision. Thus, it is possible to avoid a collision between the host vehicle and the nearby vehicle. 
     According to an eleventh embodiment of the present disclosure, priorities for CTA control may be determined through communication between a host vehicle and nearby vehicles when the host vehicle enters an intersection, and a plurality of vehicles may systematically perform CTA control at the intersection according to the determined CTA priorities. 
     Also, according to the eleventh embodiment of the present disclosure, by detecting a laterally appearing vehicle or pedestrian and then performing CTA control when a host vehicle enters an intersection, it is possible to prevent a collision. 
     With the vehicle control apparatus and method according to a twelfth embodiment of the present disclosure, the side of a host vehicle may be sensed to determine whether a collision will occur between the host vehicle and a target vehicle. 
     Also, when a collision between the host vehicle and the target vehicle is expected to occur, it is possible to prevent a collision between vehicles by generating an alert and performing emergency braking on the host vehicle. 
     According to the thirteenth embodiment of the present disclosure, it is possible to watch directions, other than a direction that a driver is watching, by means of a camera system and thus to prevent a collision between a host vehicle and a third-party vehicle. Also, it is possible to prevent a collision between the host vehicle and the third-party vehicle by controlling the host vehicle through information acquired by the camera system. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an exploded perspective view schematically showing a camera system according to a first embodiment of the present disclosure. 
         FIG. 2  is a diagram showing an example in which a vehicle is equipped with the camera system according to the first embodiment of the present disclosure. 
         FIG. 3  is a diagram showing components of the vehicle equipped with the camera system according to the first embodiment of the present disclosure. 
         FIG. 4A  is a diagram showing components of the camera system according to the first embodiment of the present disclosure. 
         FIG. 4B  is a diagram showing components of the camera system according to the first embodiment of the present disclosure. 
         FIG. 5  is an exploded perspective view illustrating a coupling relationship between a lens barrel and a lens holder according to the first embodiment of the present disclosure. 
         FIG. 6  is a diagram illustrating active alignment of the lens barrel and the lens holder according to the first embodiment of the present disclosure. 
         FIGS. 7A to 7E  are diagrams showing a lens holder  20  according to the first embodiment of the present disclosure. 
         FIGS. 8A to 8E  are diagrams showing a lens barrel  15  according to the first embodiment of the present disclosure. 
         FIG. 9  schematically illustrates a camera system according to a second embodiment of the present disclosure. 
         FIG. 10  is a schematic exploded view of a camera module according to the second embodiment. 
         FIG. 11  is a schematic exploded view of a signal processing module according to the second embodiment. 
         FIG. 12  schematically illustrates another example of the camera system according to the second embodiment. 
         FIG. 13  illustrates an example in which the camera system according to the second embodiment is mounted on a vehicle. 
         FIG. 14  illustrates another example in which the camera system according to the second embodiment is mounted on a vehicle. 
         FIG. 15  schematically illustrates a mounting module and a camera module according to the second embodiment. 
         FIG. 16  illustrates an example in which the camera module according to the second embodiment is combined with the mounting module. 
         FIG. 17  illustrates another example in which the camera module according to the second embodiment is combined with the mounting module. 
         FIG. 18  illustrates another example in which the camera module according to the second embodiment is combined with the mounting module. 
         FIG. 19  is a diagram showing a collision prevention system according to a third embodiment of the present disclosure. 
         FIG. 20  is a diagram showing a method of detecting a target vehicle with a collision risk according to the third embodiment of the present disclosure. 
         FIG. 21  is a diagram showing a method of avoiding a collision with a target vehicle by controlling the speed and steering of a host vehicle according to the third embodiment of the present disclosure. 
         FIG. 22  is a diagram showing the collision avoidance method according to the third embodiment of the present disclosure. 
         FIG. 23  is a diagram showing vehicle control according to a fourth embodiment of the present disclosure. 
         FIG. 24  is a flowchart illustrating the order of controlling a vehicle according to the fourth embodiment of the present disclosure. 
         FIG. 25  is a flowchart illustrating the order of controlling a vehicle according to the fourth embodiment of the present disclosure. 
         FIG. 26  is a diagram showing an example in which a slippery road sign is recognized using a camera system according to a fifth embodiment of the present disclosure. 
         FIG. 27  is a diagram showing an example in which an emergency braking system changes an emergency braking start time according to a degree to which a road is slippery according to the fifth embodiment of the present disclosure. 
         FIG. 28  is a diagram showing an emergency braking method according to the fifth embodiment of the present disclosure. 
         FIGS. 29A to 29C  are views illustrating lateral vehicle control according to a sixth embodiment of the present disclosure. 
         FIGS. 30A to 30C  are views illustrating longitudinal vehicle control according to the sixth embodiment of the present disclosure. 
         FIG. 31  is a flowchart illustrating vehicle control according to the sixth embodiment of the present disclosure. 
         FIG. 32A  is a diagram showing an example in which a warning for a collision risk is not issued when a steering wheel is not operated while a host vehicle is stopped at an intersection according to a seventh embodiment of the present disclosure. 
         FIG. 32B  is a diagram showing an example in which a warning for a first-level collision risk is issued when the steering wheel is operated while a host vehicle is stopped at an intersection according to the seventh embodiment of the present disclosure. 
         FIG. 33A  is a diagram showing an example in which a warning for a second-level collision risk is issued when a host vehicle starts traveling at an intersection and is expected to collide with a nearby vehicle according to the seventh embodiment of the present disclosure. 
         FIG. 33B  is a diagram showing an example in which a warning for a third-level collision risk is issued when a host vehicle starts traveling at an intersection and is expected to collide with a nearby vehicle and the steering wheel is not operated for the purpose of braking or collision avoidance according to the seventh embodiment of the present disclosure. 
         FIG. 34  is a diagram illustrating a host vehicle, a third-party vehicle, and a time-to-collision (TTC) according to an eighth embodiment of the present disclosure. 
         FIG. 35  is a diagram illustrating an autonomous emergency braking (AEB) control algorithm according to the eighth embodiment of the present disclosure. 
         FIG. 36  is a diagram showing an example in which a host vehicle recognizes an ambient situation at an intersection according to a ninth embodiment of the present disclosure. 
         FIG. 37  is a flowchart illustrating an example in which a driver is warned depending on an ambient situation of a host vehicle according to the ninth embodiment of the present disclosure. 
         FIG. 38  is a diagram showing locations of a host vehicle and a nearby vehicle at an intersection according to a tenth embodiment of the present disclosure. 
         FIG. 39  is a diagram showing two-dimensional (2D) coordinates of a nearby vehicle with respect to a host vehicle according to the tenth embodiment of the present disclosure. 
         FIG. 40  is a flowchart illustrating the order of controlling a host vehicle according to the tenth embodiment of the present disclosure. 
         FIG. 41  is a diagram showing a cross traffic alert (CTA) system according to an eleventh embodiment of the present disclosure. 
         FIG. 42  is a diagram showing controllers controlled for collision avoidance and a control unit shown in  FIG. 41 . 
         FIG. 43  is a diagram showing an example in which nearby vehicles are detected by a camera system and a radar system disposed in a host vehicle. 
         FIG. 44  is a diagram showing a method of setting control priorities of a CTA system when a plurality of vehicles enter an intersection. 
         FIG. 45  is a diagram showing a configuration of a vehicular control device according to a twelfth embodiment of the present disclosure. 
         FIG. 46  is a diagram showing sensing regions of a first information generation unit and a second information generation unit before an intersection is sensed. 
         FIG. 47  is a diagram showing a change in width of the sensing region of the second information generation unit after an intersection is sensed. 
         FIG. 48  is a diagram showing a change in length of the sensing region of the second information generation unit after an intersection is sensed. 
         FIG. 49  is an operational flowchart illustrating a vehicle control method according to the twelfth embodiment of the present disclosure. 
         FIGS. 50A and 50B  are diagrams illustrating operation of a driving assistance system during a left turn according to a thirteenth embodiment of the present disclosure. 
         FIG. 51  is a diagram illustrating operation of the driving assistance system during a right turn according to the thirteenth embodiment of the present disclosure. 
     
    
    
     MODE OF THE DISCLOSURE 
     Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings so that they can be easily practiced by those skilled in the art. The present disclosure may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. 
     To clearly describe the present disclosure, portions irrelevant to the description are omitted, and the same or similar elements are denoted by the same reference numerals. 
     In this disclosure, when one part (or element, device, etc.) is referred to as being “connected” to another part (or element, device, etc.), it should be understood that the former can be “directly connected” to the latter, or “electrically connected” to the latter via an intervening part (or element, device, etc.). Furthermore, when one part is referred to as “comprising” (or “including” or “having”) other elements, it should be understood that the part can comprise (or include or have) only those elements or other elements as well as those elements unless specifically described otherwise. 
     It will be understood that when one part is referred to as being “on” another part, it can be directly on another part or intervening parts may be present therebetween. In contrast, when a part is referred to as being “directly on” another part, there are no intervening parts therebetween. 
     It will be understood that, although the terms first, second, third, etc. may be used herein to describe various parts, components, regions, layers and/or sections, but are not limited thereto. These terms are only used to distinguish one part, component, region, layer, or section from another part, component, region, layer or section. Thus, a first part, component, region, layer, or section discussed below could be termed a second part, component, region, layer, or section without departing from the scope of the present disclosure. 
     The technical terms used herein are to simply mention a particular exemplary embodiment and are not meant to limit the present disclosure. An expression used in the singular encompasses the expression of the plural, unless it has a clearly different meaning in the context. In the specification, it is to be understood that the terms such as “including” or “having” etc., are intended to indicate the existence of specific features, regions, integers, steps, operations, elements, and/or components, and are not intended to preclude the possibility that one or more other specific features, regions, integers, steps, operations, elements, components, or combinations thereof may exist or may be added. 
     Spatially relative terms, such as “below”, “above”, and the like, may be used herein for ease of description to describe one part&#39;s relationship to another part(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different meanings or operations of a device in use in addition to the meanings depicted in the drawings. For example, if the device in the figures is turned over, parts described as “below” other parts would then be oriented “above” the other parts. Thus, the exemplary term “below” can encompass both an orientation of above and below. Devices may be otherwise rotated 90 degrees or by other angles and the spatially relative descriptors used herein are interpreted accordingly. 
     Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meanings as those generally understood by those with ordinary knowledge in the field of art to which the present disclosure belongs. Such terms as those defined in a generally used dictionary are to be interpreted to have the meanings equal to the contextual meanings in the relevant field of art, and are not to be interpreted to have idealized or excessively formal meanings unless clearly defined in the present application. 
     Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings so that they can be easily practiced by those skilled in the art to which the present disclosure pertains. The example embodiments may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. 
     First Embodiment 
       FIG. 1  is an exploded perspective view schematically showing a camera system according to the first embodiment of the present disclosure. 
     Referring to  FIG. 1 , a camera system  1  includes a lens  10 , a lens holder  20  in which the lens  10  is to be installed, and an image sensor  31  coupled to the lens holder  20  and configured to sense an image of a subject captured by the lens  10 . The image sensor  31  is disposed on an image printed circuit board (PCB)  30  and includes an image array sensor composed of pixels. For example, the image sensor  31  includes a complementary metal-oxide-semiconductor (CMOS) photo-sensor array or a charge-coupled device (CCD) photo-sensor array. Such an image sensor  31  is disposed in parallel with the lens  10 . Also, the lens  10  and the lens holder  20  may be coupled to each other through active alignment. 
     Also, the camera system  1  includes a main PCB  40 , and an image processor  41  and a camera micro-control unit (MCU)  42  are disposed on the main PCB  40 . The image processor  41  may receive image data from the image sensor  31 . To this end, the image processor  41  and the image sensor  31  may be connected through a connector (not shown). For example, the connector may be produced as a flexible PCB (FPCB) in order to maximize internal space utilization of the camera system. Through such a connector, an electric signal, power, a control signal, and the like may be transmitted or received. For example, a communication scheme between the image processor  41  and the image sensor  31  may be Inter-Integrated Circuit (I2C). The camera MCU  42  and the image processor  41  may communicate with each other in a communication scheme, such as Universal Asynchronous Receiver/Transmitter (UART) or Serial Peripheral Interface (SR). 
     The camera MCU  42  may receive image data processed by the image processor  41  and transfer the image data to an electrical control unit (ECU) (not shown) located in a vehicle. For example, a communication scheme between the camera MCU  42  and the ECU of the vehicle may be Chassis Controller Area Network (CAN). Also, the camera MCU  42  receives data processed by the image processor  41 . The data includes, for example, data regarding vehicles ahead, data regarding lanes ahead, data regarding cyclists ahead, data regarding traffic signs, data regarding Active High Beam Control (AHBC), data regarding wheel detection (e.g., data for quickly recognizing a close cut-in vehicle entering the field of view (FOV) of a camera through vehicle wheel recognition), data regarding traffic lights, data regarding road marks (e.g., an arrow on a road), data regarding VD at any angle (data for recognizing a vehicle ahead according to a previous traveling direction or angle of the vehicle), data regarding road profile (e.g., data for recognizing a road shape ahead (a curve, a speed bump, or a hole) and thus enhancing ride quality through suspension control), data regarding semantic free space (e.g., boundary labeling), data regarding general objects (a vehicle to a side, etc.), data regarding advanced path planning (e.g., data for predicting an expected vehicle traveling route through deep learning using surrounding environments even on lane-free or polluted roads), data regarding odometry (e.g., data for recognizing a driving road landmark and fusing the driving road landmark with GPS recognition information), and the like. 
     Also, the camera system  1  includes a housing  50 , and the housing  50  includes an upper housing  52  and a lower housing  54 . In detail, a pre-determined accommodation space is formed in the housing  50  composed of the upper housing  52  and the lower housing  54  coupled to each other, and the lens  10 , the lens holder  20 , the image PCB  30 , and the main PCB  40  are accommodated in the accommodation space. 
     When the camera system  1  is manufactured, the lens  10  may be installed in the lens holder  20 , and then the lens holder  20  may be coupled to the image PCB  30 . For example, the lens holder  20  and the image PCB  30  may be coupled through a screw  23 . 
     Subsequently, the upper housing  52  may be coupled to the lens holder  20  while the lens holder  20  and the image PCB  30  are coupled to each other. In this case, the upper housing  52  and the lens holder  20  may be coupled through a screw  25 . 
     The number of lenses  10  used may be changed depending on the type of the camera system  1 , the number of pixels of the image sensor, or requirements of a function implemented by the camera system  1 . For example, when a single lens  10  is used, the lens may be 52 deg when 1.3 MP is required, or for example, 100 deg when 1.7 MP is required. Alternatively, two lenses  10  may be used. Alternatively, when three lenses  10  are used, three image sensors  31  are required, and the lenses may be 28 deg, 52 deg, and 150 deg or 50 deg, 100 deg, and 150 deg, 
     The type of the camera system  1  is determined the number or types of advanced driving assistance system (ADAS) functions supported by the camera system  1 . For example, when only some of the ADAS functions are supported (when the data processed by the image processor  41  is data regarding vehicles ahead, data regarding lanes ahead, data regarding cyclists ahead, data regarding traffic signs, data regarding AHBC, data regarding wheel detection (e.g., data for quickly recognizing a close cut-in vehicle entering the FOV of a camera through vehicle wheel recognition), data regarding traffic lights, or data regarding road marks (e.g., an arrow on a road)), a single lens may be used. When more functions are supported (in addition to the above-described example, when the data processed by the image processor  41  is data regarding VD at any angle (data for recognizing a vehicle ahead according to a previous traveling direction or angle of the vehicle), data regarding road profile (e.g., data for recognizing a road shape ahead (a curve, a speed bump, or a hole) and thus enhancing ride quality through suspension control), data regarding semantic free space (e.g., boundary labeling), data regarding general objects (a vehicle to a side, etc.), data regarding advanced path planning (e.g., data for predicting an expected vehicle traveling route through deep learning using surrounding environments even on lane-free or polluted roads), or data regarding odometry (e.g., data for recognizing a driving road landmark and fusing the driving road landmark with GPS recognition information)), and the like, three lenses may be used. 
       FIG. 2  is a diagram showing an example in which a vehicle is equipped with the camera system  1  according to the first embodiment of the present disclosure. 
     As shown in  FIG. 2 , the camera system  1  may be installed below a windshield  220  or near a rear-view mirror  210  in a vehicle. Thus, the camera system  1  is used to capture a field of view ahead of the vehicle and is used to recognize an object present within the field of view ahead. Also, in case of rain or dust, it is preferable that the camera system be installed in the vehicle according to a region cleaned by a windshield wiper operating outside the windshield  220 . The location where the camera system  1  is installed is not limited thereto. The camera system  1  may be installed in a different location in order to capture a region ahead of, to a side of, and behind the vehicle. 
     Meanwhile, a radar apparatus (not shown), which is a sensor apparatus that uses electromagnetic waves to measure the distance, velocity, and angle of an object, may be typically located at a front grille of the vehicle to cover even a front lower part of the vehicle. The reason why the radar apparatus is disposed at the front grill, that is, outside the vehicle, in other words, the reason why the radar apparatus is not allowed to transmit and receive signals through the windshield  220  of the vehicle is a reduction in sensitivity when electromagnetic waves pass through glass. According to the present disclosure, the electromagnetic waves may be prevented from passing through the windshield  220  although the radar apparatus is located inside the vehicle, in particular, below the windshield inside the vehicle. To this end, the radar apparatus is configured to transmit and receive electromagnetic waves through an opening provided in an upper portion of the windshield  220 . Also, a cover is disposed at a location corresponding to the opening for the radar apparatus. The cover is to prevent loss (e.g., an inflow of air, etc.) due to the opening. Also, it is preferable that the cover be made of a material capable of easily transmitting electromagnetic waves of frequencies the radar apparatus uses. As a result, the radar apparatus is located inside the vehicle, but electromagnetic waves are transmitted and received through the opening provided in the windshield  220 . The cover corresponding to the opening is provided in order to prevent the loss due to the opening, and the electromagnetic waves are transmitted and received through the cover. The radar apparatus may use beam aiming, beam selection, digital beam forming, and digital beam steering. Also, the radar apparatus may include an array antenna or a phased array antenna. 
     The above-described camera system  1  and the radar apparatus (not shown) may interoperate with each other in order to improve performance to sense objects ahead. For example, the image processor  41  and a radar processor (not shown) may interoperate with each other to enlarge or focus an object of interest ahead. When the radar apparatus and the front-view camera interoperate with each other, the image sensor  31  and the radar apparatus may be disposed on the same substrate (e.g., the image PCB  30 ). 
     Also, an apparatus or system for sensing an object within a field of view ahead, such as the camera system  1  or the radar apparatus (not shown), may be used for the ADAS technology such as Adaptive Cruise Control (ACC). Also, the apparatus or system may be used to recognize a potential dangerous situation ahead. For example, the apparatus or system may be used to recognize another vehicle, a person, and an animal ahead. Also, the apparatus or system for sensing an object within a field of view ahead, such as the camera system  1  or radar apparatus (not shown) may be used in a lane departure warning system, an object detection system, a traffic sign recognition system, a lane keeping assistance system a lane change assistance system, a blind spot warning system, an automatic headlamp control system, a collision prevention system, etc. 
       FIG. 3  is a diagram showing components of the vehicle equipped with the camera system  1  according to the first embodiment of the present disclosure. 
     The components of the vehicle may be classified into MCU level, ECU level, and controller level. 
     The MCU level includes a lidar MCU, a radar MCU, a GPS MCU, a navigation MCU, and a V2X MCU, as well as a camera MCU  42 . Each of the MCUs belonging to the MCU level controls a sensing apparatus connected to a corresponding MCU or an apparatus (e.g., a processor) connected to the sensing apparatus and receives data from the sensing apparatus or the apparatus connected to the sensing apparatus. 
     The camera MCU  42  will be described as an example. The image sensor  31  captures an image of a subject captured through the lens  10 , the image processor  41  receives the data from the image sensor  31  and processes the received data, and the camera MCU  42  receives the data from the image processor  41 . The camera MCU  42  controls the image sensor  31  and the image processor  41 , and the control includes, for example, power supply control, reset control, clock (CLK) control, data communication control, power control, memory control, and the like. The image processor  41  may process data sensed and output by the image sensor  31 , and the processing includes a process of enlarging a sensed object ahead or a process of focusing on a region of the object within the entire region of view. 
     The lidar MCU  311  will be described as an example. The lidar MCU  311  is connected to a lidar apparatus, which is a kind of sensor. The lidar apparatus may be composed of a laser transmission module, a laser detection module, a signal collection and processing module, and a data transmission and reception module. Laser light sources with wavelengths of 250 nm to 11 μm or variable wavelengths are used. Also, the lidar apparatus is classified into a time of fight (TOF) scheme and a phase shift scheme according to a signal modulation scheme. The lidar MCU  311  controls the lidar apparatus and another apparatus (e.g., a lidar processor (not shown) for processing a lidar sensing output) connected to the lidar apparatus. The control includes, for example, power supply control, reset control, clock (CLK) control, data communication control, memory control, etc. Meanwhile, the lidar apparatus is used to sense a region ahead of the vehicle. The lidar apparatus is located at a front inner side of the vehicle, in particular, below the windshield  220  to transmit and receive laser light through the windshield  220 . 
     The radar MCU  312  will be described as an example. The radar MCU  312  is connected to a radar apparatus, which is a kind of sensor. The radar apparatus is a sensor apparatus that uses electromagnetic waves to measure the distance, speed, or angle of an object. The radar apparatus may be used to sense objects ahead within a horizontal angle of 30 degrees and a distance of 150 meters by Frequency Modulation Carrier Wave (FMCVV) or Pulse Carrier. The radar MCU  312  controls the radar apparatus and another apparatus (e.g., a radar processor (not shown) for processing a radar sensing output) connected to the radar apparatus. The control includes, for example, power supply control, reset control, clock (CLK) control, data communication control, memory control, etc. Meanwhile, the radar apparatus typically uses a 77-GHz band radar or other appropriate frequency bands to sense a region ahead of the vehicle. The information acquired from the radar apparatus may be used for the ADAS technology such as ACC. Also, the radar processor may process data sensed and output by the radar apparatus. The processing includes a process of enlarging a sensed object ahead or a process of focusing on a region of the object within the entire region of view. 
     The GPS MCU  313  will be described as an example. The GPS MCU  313  is connected to a GPS apparatus, which is a kind of sensor. The GPS apparatus is an apparatus for measuring the location, speed, and time of a vehicle through communication with a satellite. In detail, the GPS apparatus is an apparatus for measuring a delay time of radio waves emitted from a satellite and obtaining a current location from a distance from an obit. The GPS MCU  313  controls the GPS apparatus and another apparatus (e.g., a GPS processor (not shown) for processing a GPS sensing output) connected to the GPS apparatus. The control includes, for example, power supply control, reset control, clock (CLK) control, data communication control, memory control, etc. 
     The navigation MCU  314  will be described as an example. The navigation MCU  314  is connected to a navigation apparatus, which is a kind of sensor. The navigation apparatus is an apparatus for displaying map information through an display apparatus installed at a front side inside the vehicle. In detail, the map information is stored in a memory apparatus, and represents the current location of the vehicle measured through the GPS apparatus in map data. The navigation MCU  314  controls the navigation apparatus and another apparatus (e.g., a navigation processor (not shown) for processing a navigation sensing output) connected to the navigation apparatus. The control includes, for example, power supply control, reset control, clock (CLK) control, data communication control, memory control, etc. 
     The V2X MCU  315  will be described as an example. The V2X MCU  315  is connected to a V2X apparatus, which is a kind of sensor. In detail, the V2X apparatus is an apparatus for performing vehicle-to-vehicle communication (V2V communication), vehicle-to-infrastructure (V21) communication, or vehicle-to-mobile (V2M) communication. The V2X MCU  315  controls the V2X apparatus and another apparatus (e.g., a V2X processor (not shown) for processing a V2X sensing output) connected to the V2X apparatus. The control includes, for example, power supply control, reset control, clock (CLK) control, data communication control, memory control, etc. 
     An electrical control unit (ECU)  320  belonging to the ECU level is an apparatus for integrally controlling a plurality of electronic apparatuses used in the vehicle. For example, the ECU  320  may control all of the MCUs belonging to the MCU level and controllers belonging to the controller level. The ECU  320  receives the sensing data from the MCUs, generates a control command for controlling a controller according to a situation, and transmits the control command to the controller. In this specification, for convenience of description, the ECU level is described as a level higher than the MCU level. However, one of the MCUs belonging to the MCU level may serve as an ECU, and two of the MCUs may serve as an ECU in combination. 
     In the controller level, there are a driver warning controller  331 , a head lamp controller  332 , a vehicle posture controller  333 , a steering controller  334 , an engine controller  335 , a suspension controller  336 , a brake controller  337 , and the like. The controller controls the components of the vehicle on the basis of the control commands received from the MCUs in the MCU level or the ECU  320 . 
     The driver warning controller  331  will be described as an example. The driver warning controller  331  generates an audio warning signal, a video warning signal, or a haptic warning signal in order to warn a driver of a specific dangerous situation. For example, the driver warning controller  331  may use a vehicle sound system to output warning sounds. Alternatively, in order to display a warning message, the driver warning controller  331  may output a warning message through a head-up display (HUD) or a side mirror display. Alternatively, in order to generate a warning vibration, the driver warning controller  331  may operate a vibration motor mounted on a steering wheel. 
     The head lamp controller  332  will be described as an example. The head lamp controller  332  is located at a front side of the vehicle to control a head lamp for securing a driver&#39;s field of view ahead of the vehicle at night. For example, the head lamp controller  332  may perform high beam control, low beam control, left and right auxiliary light control, adaptive head lamp control, etc. 
     The vehicle posture controller  333  will be described as an example. The vehicle posture controller  333  is referred to as vehicle dynamic control (VDC) or electrical stability control (ESP), and performs control to correct the vehicle&#39;s behavior through electronic equipment when the vehicle&#39;s behavior suddenly becomes unstable due to a road condition or a driver&#39;s urgent steering wheel operation. For example, sensors such as a wheel speed sensor, a steering angle sensor, a yaw rate sensor, and a cylinder pressure sensor sense a steering wheel operation. When the running direction of the steering wheel does not match that of the wheels, the vehicle posture controller  333  performs control to disperse the braking force of each wheel using an anti-lock braking system (ABS) or the like. 
     The steering controller  334  will be described as an example. The steering controller  334  controls an electronic power steering system (MPDS) for driving the steering wheel. For example, when the vehicle is expected to collide, the steering controller  334  controls the steering of the vehicle such that the collision may be avoided or such that damage may be minimized. 
     The engine controller  335  will be described as an example. The engine controller  335  serves to control elements such as an injector, a throttle, a spark plug, etc. according to control commands when the ECU  320  receives data from an oxygen sensor, an air quantity sensor, and a manifold absolute pressure sensor. 
     The suspension controller  336  will be described as an example. The suspension controller  336  is an apparatus for performing motor-based active suspension control. In detail, by variably controlling the damping force of a shock absorber, the suspension controller  336  provides smooth ride quality during normal running and provides hard ride quality during high-speed running or upon posture changes. Thus, it is possible to ensure ride comfort and driving stability. Also, the suspension controller  336  may perform vehicle height control, posture control, or the like as well as the damping force control. 
     The brake controller  337  will be described as an example. The brake controller  337  controls whether to operate the brake of the vehicle and controls the pedal effort of the brake. For example, when a forward collision is probable, the brake controller  337  may perform control so that emergency braking is automatically activated according to a control command of the ECU  320  irrespective of whether the driver operates the brake. 
     As described above with reference to the drawings, the MCU, ECU, and controller have been described as independent elements. However, it should be understood that the present disclosure is not limited thereto. Two or more MCUs may be integrated into a single MCU and may interoperate with each other. Two or more MCUs and an ECU may be integrated as a single apparatus. Two or more controllers may be integrated into a single controller and may interoperate with each other. Two or more controllers and an ECU may be integrated as a single apparatus. 
     For example, the radar processor processes an output of the radar apparatus, and the image processor  41  processes an output of the image sensor  31 . The output of the radar apparatus and the output of the image sensor  31  may interoperate with a single processor (e.g., the radar processor, the image processor  41 , an integrated processor, or the ECU  320 ). For example, the radar processor processes data sensed and output by the radar apparatus. Based on information regarding an object ahead, which is derived from a result of the processing, the image processor  41  may perform a process of enlarging or focusing on data sensed and output by the image sensor  31 . On the other hand, the image processor  41  processes the data sensed and output by the image sensor  31 . Based on information regarding an object ahead, which is derived from a result of the processing, the radar processor may perform a process of enlarging or focusing on data sensed and output by the radar apparatus. To this end, the radar MCU may control the radar apparatus to perform beam aiming or beam selection. Alternatively, the radar processor may perform digital beam forming or digital beam steering in an array antenna or a phased array antenna system. In this way, when the radar apparatus and the front-view camera interoperate with each other, the image sensor  31  and the radar apparatus may be disposed on the same substrate (e.g., the image PCB  30 ). 
       FIG. 4A  is a diagram showing components of the camera system  1  according to the first embodiment of the present disclosure. 
     Referring to  FIG. 4A , the camera system  1  includes a lens  10 , an image sensor  31 , an image processor  41 , and a camera MCU  42 . 
     Also, the camera system  1  includes a first converter unit  421  configured to receive an ignition voltage  410  and convert the ignition voltage  410  into a first voltage  411 , a second voltage  412 , and a third voltage  413 , a second converter unit  422  configured to receive the third voltage  413  and convert the third voltage  413  into a fourth voltage  414 , and a regulator unit  423  configured to receive the first voltage  411  and convert the first voltage  411  into a fifth voltage  415  and a sixth voltage  416 . As shown in  FIG. 4A , the first converter unit  421  may be composed of a single 3ch DC-DC converter. However, the present disclosure is not limited thereto, and the first converter unit  421  may be composed of a 1ch DC-DC converter and a 2ch DC-DC converter or may be composed of three 1ch DC-DC converters. As shown in  FIG. 4A , the regulator unit  423  may be composed of a 2ch low-dropout (LDO). However, the present disclosure is not limited thereto, and the regulator unit  423  may be composed of two 1ch LDOs. The reason why the regulator unit  423  is implemented with an LDO is that an electric current level required by the image sensor  31  is not high. 
     The ignition voltage  410 , which is a voltage generated when the driver starts the vehicle by turning a vehicle key or pushing a start button, may be generally 14 V. The first voltage  411 , which is a voltage into which the first converter unit  421  receives and converts the ignition voltage  410 , may be 3.3 V. The first voltage  411  may be input to the camera MCU  42  and may be used as power for operating the camera MCU  42 . Also, the first voltage  411  may be used as power for operating a monitoring module  441  and a first memory  431 . Also, the first voltage  411  may be used as power for operating the image processor  41 . The reason why the same operating power, that is, the first voltage  411  is applied to the camera MCU  42  and the image processor  41  is to allow the two communication components to have the same communication level (IO voltage). The second voltage  412 , which is a voltage into which the first converter unit  421  receives and converts the ignition voltage  410 , may be 1.8 V. Meanwhile, as described below, the fifth voltage (e.g., 1.8 V) is applied to the image sensor  31 , and this voltage is the same as the second voltage. The reason why the second voltage  412  applied to the image processor  41  is the same as the fifth voltage  415  applied to the image sensor  31  is to allow the image processor  41  and the image sensor  31  to have the same communication level (IO voltage). The third voltage  413 , which is a voltage into which the first converter unit  421  receives and converts the ignition voltage  410 , may be 5 V. The third voltage  413  may be applied to the second converter unit  422 , and the second converter unit  422  may output the fourth voltage  414 . The fourth voltage  414  is applied to the image processor  41  and is operable as core power of the image processor  41 . For example, the fourth voltage  414  may be 1.2 V. Meanwhile, the reason why the first converter unit  421  outputs the third voltage  413  and the second converter unit  422 , which receives the third voltage  413 , outputs the fourth voltage  414  even if the first converter unit  421  is capable of directly outputting the fourth voltage  414 , is to satisfy an allowable electric current required by the image processor  41 . In addition, the reason is to use the third voltage  413  as power for operating other components (e.g., HS-CAN TRx). 
     The first voltage  411  is applied to the regulator unit  423 , and the regulator unit  423  outputs the fifth voltage  415  and the sixth voltage  416 . The fifth voltage  415  may be 1.8 V, and the sixth voltage  416  may be 2.8 V. The fifth voltage  415  is applied to the image sensor  31  to allow the image sensor  31  and the image processor  41  to have the same communication level. The sixth voltage  416  is applied to the image sensor  31  and is operable as core power of the image sensor  31 . As a result, the camera MCU  42  and the image processor  41  have the same communication level set to the first voltage  411 , and the image processor  41  and the image sensor  31  have communication levels set to the second voltage  412  and the fifth voltage  415  equal to the second voltage  412 . 
     Also, the camera system  1  includes a first memory  431  connected to the camera MCU  42  and configured to receive the first voltage  411 , a second memory  432  connected to the image processor  41 , a third memory  433  connected to the image processor  41 , and a fourth memory  434  connected to the image processor  41 . The first memory  431  may be an electrically erasable programmable read-only memory (EEPROM), the second memory  432  may be a low power double-data-rate 2 (LPDDR2), the third memory  433  may be an LPDDR2, and the fourth memory  434  may be a flash memory. The first memory  431  is connected to the camera MCU  42  to store MCU logic data (an algorithm for controlling a controller) and MCU basic software (a startup algorithm for driving the image processor  41 , the image sensor  31 , and the like). The second memory  432  is connected to the image processor  41  and serves to execute a function implementation algorithm stored in the fourth memory  434  according to a command from the image processor  41 . The third memory  433  is connected to the image processor  41  and serves to execute the function implementation algorithm stored in the fourth memory  434  according to a command from the image processor  41 . The fourth memory  434  is connected to the image processor  41  to store algorithm data (e.g., LD, PD, VD, TSR, etc.) used by the image processor  41  to implement functions. The second memory  432  and the third memory  433  may have capacity determined depending on the number of functions supported by the camera system  1 . For example, when only some of the functions are supported (when the data processed by the image processor  41  is data regarding vehicles ahead, data regarding lanes ahead, data regarding cyclists ahead, data regarding traffic signs, data regarding AHBC, data regarding wheel detection (e.g., data for quickly recognizing a close cut-in vehicle entering the FOV of a camera through vehicle wheel recognition), data regarding traffic lights, or data regarding road marks (e.g., an arrow on a road)), the second memory  432  and the third memory  433  may be each 128 MB. When more functions are supported (in addition to the above-described example, when the data processed by the image processor  41  is data regarding VD at any angle (data for recognizing a vehicle ahead according to a previous traveling direction or angle of the vehicle), data regarding road profile (e.g., data for recognizing a road shape ahead (a curve, a speed bump, or a hole) and thus enhancing ride quality through suspension control), data regarding semantic free space (e.g., boundary labeling), data regarding general objects (a vehicle to a side, etc.), data regarding advanced path planning (e.g., data for predicting an expected vehicle traveling route through deep learning using surrounding environments even on lane-free or polluted roads), or data regarding odometry (e.g., data for recognizing a driving road landmark and fusing the driving road landmark with GPS recognition information)), the second memory  432  and the third memory  433  may be each 256 MB. Also, the second memory  432  and the third memory  433  may be integrated into a single memory depending on the number of lenses  10 . When only one lens  10  is used, a total of two memories, i.e., the second memory  432  and the third memory  433  may be used (e.g., 2×218 MB). When two lenses  10  are used, a single memory having a larger capacity than those of the two memories may be used (e.g., 1×512 MB). Also, when three lenses  10  are used, two memories having large capacity may be used (e.g., 2×512 MB). That is, the second memory  432  and the third memory  433  may be changed in number and capacity depending on the number of lenses. 
     Also, the camera system  1  includes a monitoring module  441  connected to the camera MCU  42 , a high-speed CAN transceiver (HS-CAN_TRx)  442  connected to the camera MCU  42  to perform chassis CAN communication, a high-speed CAN transceiver  443  connected to the camera MCU  42  to perform local CAN communication, an external input unit  444  connected to the camera MCU  42  to receive a windshield wiper operation input, an external input unit  445  connected to the camera MCU  42  to receive an on/off switching input, and an external output unit  446  connected to the camera MCU  42  to output a light-emitting diode (LED) signal. The reason why the camera MCU  42  receives a windshield wiper operation input is that when a windshield wiper ON signal is received, recognition of a region ahead through the camera system  1  is degraded due to rain and thus there is a need to turn off the camera MCU  42  or switch off a specific function of the camera MCU  42 . 
       FIG. 4B  is a diagram showing components of the camera system  1  according to the first embodiment of the present disclosure. 
     Referring to  FIG. 4B , the camera system  1  may include a lens  10 , an image sensor  31 , an image processor  41 , and a camera MCU  42 . 
     Also, the camera system  1  includes a first converter unit  421  configured to receive an ignition voltage  510  and covert the ignition voltage  510  into a first voltage  511 , a second voltage  512 , a third voltage  513 , and the fourth voltage  514  and a regulator unit  523  configured to receive the first voltage  511  and convert the first voltage  511  into a fifth voltage  515 , a sixth voltage  516 , and a seventh voltage  517 . As shown in  FIG. 4B , the first converter unit  521  may be composed of a single 4ch DC-DC converter. However, the present disclosure is not limited thereto, and the first converter unit  521  may be composed of a 1 ch DC-DC converter and a 3ch DC-DC converter, may be composed of two 2ch DC-DC converters, or may be composed of four 1ch DC-DC converters. Alternatively, the first converter unit  521  may be composed of a 4ch power management integrated circuit (PMIC). By using a PMIC, it is advantageously possible to mount a plurality of buck regulators, mount a boost regulator, support a universal serial bus (USB) function, and provide an I2C function for power setting. As shown in  FIG. 4B , the regulator unit  523  may be composed of a 3ch LDO. However, the present disclosure is not limited thereto, and the regulator unit  523  may be composed of three 1ch LDOs. The reason why the regulator unit  523  is implemented with an LDO is that an electric current level required by the image sensor  31  is not high. 
     The ignition voltage  510 , which is a voltage generated when the driver starts the vehicle by turning the vehicle key or pushing the start button, may be generally 14 V. The first voltage  511 , which is a voltage into which the first converter unit  521  receives and converts the ignition voltage  510 , may be 3.3 V. The first voltage  511  may be input to the camera MCU  42  and may be used as power for operating the camera MCU  42 . Also, the first voltage  511  may be used as power for operating a monitoring module  541  and a first memory  531 . Also, the first voltage  511  may be used as power for operating the image processor  41 . The reason why the same operating power, that is, the first voltage  511  is applied to the camera MCU  42  and the image processor  41  is to allow the two communication components to have the same communication level (10 voltage). The second voltage  512 , which is a voltage into which the first converter unit  521  receives and converts the ignition voltage  510 , may be 1.8 V. As described below, the fifth voltage  515  (e.g., 1.8 V) is applied to the image sensor  31 , and this voltage is the same as the second voltage  512 . The reason why the second voltage  512  applied to the image processor  41  is the same as the fifth voltage  515  applied to the image sensor  31  is to allow the image processor  41  and the image sensor  31  to have the same communication level (10 voltage). The third voltage  513 , which is a voltage into which the first converter unit  521  receives and converts the ignition voltage  510  and which the first converter unit  521  outputs, may be 5 V. The third voltage  513  may be used as power for driving components (e.g., an S-CAN communication module, a C-CAN communication module, a high side driver, and the like) used by the camera MCU  42  to perform communication. The fourth voltage  514 , which is a voltage into which the first converter unit  521  receives and converts the ignition voltage  510  and which the first converter unit  521  outputs, may be 2.8V. The fourth voltage  514  may be converted into 1.1 V through a converter and then may be applied to the image processor  41 . The voltage of 1.1 V operates as core power of the image processor  41 . The reason why the first converter unit  521  lowers the fourth voltage  514  (2.8 V) to the core power (1.1 V) of the image processor through a separate converter even if the first converter unit  521  can directly output the core power (1.1 V) is to satisfy an allowable electric current required by the image processor  41 . 
     The first voltage  511  is applied to the regulator unit  523 , and the regulator unit  523  outputs the fifth voltage  515 , the sixth voltage  516 , and the seventh voltage  517 . The fifth voltage  515  may be 1.8 V, the sixth voltage  516  may be 2.8 V, and the seventh voltage  517  may be 1.2 V. The fifth voltage  515  is applied to the image sensor  31  and is operable to allow the image sensor  31  and the image processor  41  to have the same communication level. The sixth voltage  516  is applied to the image sensor  31  and is operable as core power of the image sensor  31 . As a result, the camera MCU  42  and the image processor  41  have the same communication level set to the first voltage  511 , and the image processor  41  and the image sensor  31  have communication levels set to the second voltage  512  and the fifth voltage  515  equal to the second voltage  412 . 
     Also, the camera system  1  includes a first memory  531  connected to the camera MCU  42  and configured to receive the first voltage  511 , a second memory  532  connected to the image processor  41 , and a third memory  533  connected to the image processor  41 . The first memory  531  may be an EEPROM, the second memory  532  may be a low power double-data-rate 4 (LPDDR4), and the third memory  533  may a flash memory. The first memory  531  is connected to the camera MCU  42  to store MCU logic data (an algorithm for controlling a controller) and MCU basic software (a startup algorithm for driving the image processor  41 , the image sensor  31 , and the like). The second memory  532  is connected to the image processor  41  and serves to execute a function implementation algorithm stored in the third memory  533  according to a command from the image processor  41 . The third memory  533  is connected to the image processor  41  to store algorithm data (e.g., LD, PD, VD, TSR, etc.) used by the image processor  41  to implement functions. The second memory  532  may have capacity determined depending on the number of functions supported by the camera system  1 . For example, when only some of the functions are supported (when the data processed by the image processor  41  is data regarding vehicles ahead, data regarding lanes ahead, data regarding cyclists ahead, data regarding traffic signs, data regarding AHBC, data regarding wheel detection (e.g., data for quickly recognizing a close cut-in vehicle entering the FOV of a camera through vehicle wheel recognition), data regarding traffic lights, or data regarding road marks (e.g., an arrow on a road)), the second memory  532  may be 128 MB. When more functions are supported (in addition to the above-described example, when the data processed by the image processor  41  is data regarding VD at any angle (data for recognizing a vehicle ahead according to a previous traveling direction or angle of the vehicle), data regarding road profile (e.g., data for recognizing a road shape ahead (a curve, a speed bump, or a hole) and thus enhancing ride quality through suspension control), data regarding semantic free space (e.g., boundary labeling), data regarding general objects (a vehicle to a side, etc.), data regarding advanced path planning (e.g., data for predicting an expected vehicle traveling route through deep learning using surrounding environments even on lane-free or polluted roads), or data regarding odometry (e.g., data for recognizing a driving road landmark and fusing the driving road landmark with GPS recognition information)), the second memory  432  may be 256 MB. 
     Also, the camera system  1  includes a monitoring module  541  connected to the camera MCU  42 , a high-speed CAN transceiver (HS-CAN_TRx)  542  connected to the camera MCU  42  to perform chassis CAN communication, a high-speed CAN transceiver  543  connected to the camera MCU  42  to perform local CAN communication, a high side driver  544  connected to the camera MCU  42  to output an LED signal, and an external input unit  545  connected to the camera MCU  42  to receive an on/off switching input. Also, the camera system  1  may include an external input receiver (not shown) connected to the camera MCU  42  to receive a wire input. The reason why the camera MCU  42  receives a windshield wipe operation input is that when a windshield wiper ON signal is received, recognition of a region ahead through the camera system  1  is degraded due to rain and thus there is a need to turn off the camera MCU  42  or switch off a specific function of the camera MCU  42 . 
     The above-described camera system  1  may be used to implement at least one of the following functions: Road Boundary Departure Prevention Systems (RBDPS), Cooperative Adaptive Cruise Control Systems (CACC), Vehicle/roadway warning systems, Partially Automated Parking Systems (PAPS), Partially Automated Lane Change Systems (PALS), Cooperative Forward Vehicle Emergency Brake Warning Systems (C-FVBWS), Lane Departure Warning Systems (LDWS), Pedestrian Detection and Collision Mitigation Systems (PDCMS), Curve Speed Warning Systems (CSWS), Lane Keeping Assistance Systems (LKAS), Adaptive Cruise Control systems (ACC), Forward Vehicle Collision Warning Systems (FVCWS), Manoeuvring Aids for Low Speed Operation systems (MALSO), Lane Change Decision Aid Systems (LCDAS), Low Speed Following systems (LSF), Full Speed Range Adaptive cruise control systems (FSRA), Forward Vehicle Collision Mitigation Systems (FVCMS), Extended Range Backing Aids systems (ERBA), Cooperative Intersection Signal Information and Violation Warning Systems (CIWS), and Traffic Impediment Warning Systems (TIWS). 
       FIG. 5  is an exploded perspective view illustrating a coupling relationship between a lens barrel and a lens holder according to the first embodiment of the present disclosure. 
     According to the present disclosure, the lens  10  is inserted into a lens barrel  15 , and the lens barrel  15  includes a flange  15 - 1 . The lens barrel  15  and the lens holder  20  are coupled to each other by a body of the lens barrel  15  including the lens  10  and the flange  15 - 1  being inserted into the lens holder  20 . Also, the lens barrel  15  and the lens holder  20  may be coupled to each other through active alignment. This will be described below with reference to  FIG. 6 . 
       FIG. 6  is a diagram illustrating active alignment of the lens barrel and the lens holder according to the first embodiment of the present disclosure. 
     The active alignment is used when the lens barrel  15  is coupled to the lens holder  20 . In this case, the active alignment refers to an operation of placing an adhesive material  600  between the flange  15 - 1  of the lens barrel  15  and an upper surface  25  of the lens holder  20  and changing the location of the lens barrel  15  horizontally or vertically to focus an object recognized through the image sensor  31 . As a representative example, epoxy that is deformable before hardening and that has strong adhesion after hardening may be used as the adhesive material  600 . 
     According to a conventional scheme, a lower surface  15 - 2  of the flange  15 - 1  and the upper surface  25  of the lens holder  20 , which are to be in contact with the adhesive material  600 , may be flat. According to such a conventional scheme, there is no problem in attaching the lens barrel  15  and the lens holder  20 . However, when an impact occurs in the camera or when an extreme situation occurs in terms of temperature, the adhesive strength of the adhesive material  600  is degraded, and the lens barrel  15  and the lens holder  20  are separated from each other. 
       FIGS. 7A to 7E  are diagrams showing the lens holder  20  according to the first embodiment of the present disclosure. In detail,  FIG. 7A  is a perspective view of the lens holder  20 , and  FIGS. 7B to 7E  are top views of the lens holder  20 , which show the upper surface  25  of the lens holder  20 . As shown in  FIGS. 7B to 7E , a groove  27  may be formed on the upper surface  25  of the lens holder  20 . The groove  27  may be a single circular groove ( FIG. 7B ), a dual circular groove ( FIG. 7C ), a cross lattice groove ( FIG. 7D ), or a zigzag groove ( FIG. 7E ). Such a groove  27  may be formed using a laser. By the groove  27  increasing the surface roughness of the upper surface  25  of the lens holder  20 , it is possible to maximize an area brought into contact with the adhesive material  600  and thus also to maximize the adhesive strength. 
       FIGS. 8A to 8E  are diagrams showing the lens barrel  15  according to the first embodiment of the present disclosure. In detail,  FIG. 8A  is a perspective view of the lens barrel  15 , and  FIGS. 8B to 8E  are bottom views of the lens barrel  15 , which show a lower surface  15 - 2  of the flange  15 - 1  of the lens barrel  15 . As shown in  FIGS. 8B to 8E , a groove  15 - 3  may be formed on the lower surface  15 - 2  of the flange  15 - 1  of the lens barrel  15 . The groove  15 - 3  may be a single circular groove ( FIG. 8B ), a dual circular groove ( FIG. 8C ), a cross lattice groove ( FIG. 8D ), or a zigzag groove ( FIG. 8E ). Such a groove  15 - 3  may be formed using a laser. By the groove  15 - 3  increasing the surface roughness of the lower surface  15 - 2  of the flange  15 - 1  of the lens barrel  15 , it is possible to maximize an area brought into contact with the adhesive material  600  and thus also to maximize the adhesive strength. 
     Second Embodiment 
       FIG. 9  schematically illustrates a camera system according to a second embodiment of the present disclosure.  FIG. 10  is a schematic exploded view of a camera module according to the second embodiment.  FIG. 11  is a schematic exploded view of a signal processing module according to the second embodiment. 
     Referring to  FIG. 9 , a camera system  1  includes a camera module  700  that captures an image and obtains image data and a signal processing module  800  that processes image data. 
     The camera module  700  and the signal processing module  800  include different housings  710  and  810 , and may be electrically connected to each other through a first cable  801 . 
     The signal processing module  800  may supply power to the camera module  700  through the first cable  801 , and the camera module  700  may provide the captured image data to the signal processing module  800  through the first cable  801  in real time and in succession. In addition, the signal processing module  800  may provide a control signal to the ECU of the vehicle through the second cable  802 . 
     Referring to  FIG. 10 , the camera module  700  may include a lens  10 , a lens holder  20  on which the lens  10  is installed, and an image sensor  31  that is coupled to the lens holder  20 , and may capture an image of a subject through the lens  10 . The image sensor  31  is disposed on the image PCB  30  and includes an image array sensor composed of pixels. For example, the image sensor  31  includes a CMOS photosensor array or a CCD photosensor array. The image sensor  31  is disposed parallel to the lens  10 . In addition, the lens  10  and the lens holder  20  may be coupled to each other in an Active Alignment method, as exemplified in  FIG. 6  and the corresponding paragraphs. 
     The camera module  700  may be electrically connected to the signal processing module  800  through the first cable  801 . For example, the camera module  700  may receive power from the signal processing module  800  through the first cable  801 , and transmit image data to the signal processing module  800  through the first cable  801 . The first cable  801  may include, for example, a solid cable, a twisted pair cable, a coaxial cable, or an optical fiber cable. 
     The camera module  700  also includes a first interface  721  for electrically connecting the first cable  801  and the image sensor  31 . 
     The first interface  721  is provided on the image PCB  30  and may be electrically connected to the image sensor  31  through the image PCB  30 . In addition, the first interface  721  may be electrically connected to the first cable  801 . 
     The first interface  721  and the first cable  801  may be manufactured according to various standards. 
     For example, the first interface  721  and the first cable  801  may be manufactured according to the Coaxpress standard. According to the Coaxpress standard, the bandwidth of the first interface  721  and the first cable  801  may be 325 MB/s or 625 MB/s or 1.25 GB/s, and not only data can be transmitted, but power can be transmitted. The first interface  721  and the first cable  801  may transmit a camera control signal of the signal processing module  800  to the camera module  700 . The first interface  721  and the first cable  801  according to the Coaxpress standard may be manufactured according to a standard coaxial cable. 
     As another example, the first interface  721  and the first cable  801  may be manufactured according to a camera link standard. According to the camera link standard, the bandwidth of the first interface  721  and the first cable  801  may be 255 MB/s or 510 MB/s or 850 MB/s, and not only data can be transmitted, but power can be transmitted. 
     As still another example, the first interface  721  and the first cable  801  may be manufactured according to a Universal Serial Bus (USB) standard. According to the USB standard, the bandwidth of the first interface  721  and the first cable  801  may be 480 MB/s or 625 MB/s, and not only data can be transmitted, but power can be transmitted. 
     As another example, the first interface  721  and the first cable  801  may be manufactured according to a Gigabit Ethernet (GIGE) standard. According to the GIGE standard, the bandwidth of the first interface  721  and the first cable  801  may be 125 MB/s or 625 MB/s or 1.25 GB/s, and not only data can be transmitted, but power can be transmitted. 
     In addition, the camera module  700  includes a first housing  710  including a front cover  711  and a rear cover  712 . The first housing  710  accommodates a lens  10 , a lens holder  20 , and an image PCB  30 . 
     A first opening  711   a  is formed in the front cover  711  so that the subject image can reach the image sensor  31  through the lens  10 . When the camera module  700  is assembled, the lens  10  and the lens holder  20  may pass through the first opening  711   a  and protrude forward of the front cover  711 . 
     A first groove  712   a  through which the first cable  801  can pass may be formed on the upper side of the rear cover  712 . When the camera module  700  is assembled, the first cable  801  may pass through the first groove  712   a  and be connected to the image PCB  30 . 
     In the case of manufacturing such a camera module  700 , after installing the lens  10  to the lens holder  20 , the lens holder  20  may be coupled to the image PCB  30 . For example, the lens holder  20  and the image PCB  30  may be coupled through screws. Next, the front cover  711  may be coupled in a state in which the lens holder  20  and the image PCB  30  are coupled. 
     Referring to  FIG. 11 , the signal processing module  800  includes a main PCB  40  and an image processor  41  and a camera micro control unit (MCU)  42  are disposed on the main PCB  40 . 
     The image processor  41  receives image data from the camera module  700  through the first cable  801 , and for this purpose, the image processor  41  may be connected to the first cable  801  through the second interface  822 . 
     The second interface  822  is provided on the main PCB  40  and may be electrically connected to the image processor  41  through the main PCB  40 . In addition, the second interface  822  may be electrically connected to the first cable  801 . 
     The second interface  822  and the first cable  801  may be manufactured according to various standards. For example, the second interface  822  and the first cable  801  may be manufactured according to a Coaxpress or a camera link, a universal serial bus or a Gigabit Ethernet standard. 
     The camera MCU  42  receives the data processed by the image processor  41 . The data includes, for example, data on the vehicle ahead, data on the lane ahead, data on the cyclist ahead, data on traffic signs, data on active high beam control (AHBC), data on wheel detection (e.g., data for faster vehicle recognition through vehicle wheel recognition for a Close Cut-in vehicle entering the camera FOV), data on traffic lights, and data on road markings (e.g., arrows on the road), data on VD at any angle (data for recognizing the vehicle with respect to the entire driving direction or angle of the front vehicle), Data on the road profile (e.g., data for improving ride comfort through suspension control by recognizing the shape of the road ahead (curve, speed bump or hole)), data on semantic free space (e.g., boundary labeling), data on general objects (side vehicles, etc.), data on advanced path planning (e.g., data for predicting the expected driving path of vehicle through deep learning through the surrounding environment even on roads with no lanes or contaminated roads), data for odometry (eg, data for recognizing a driving road landmark and fusing it with recognition information of GPS), and the like. 
     In this way, the camera MCU  42  receives image data processed by the image processor  41 , and can transmit the image data to an electrical control unit (ECU) (not shown) in the vehicle through the second cable  802 . The communication method between the camera MCU  42  and the ECU of the vehicle may be, for example, a Chassis controller area network (CAN). In this case, the camera MCU  42  may be connected to the second cable  802  through the third interface  823 . 
     The third interface  823  is provided on the main PCB  40  and may be electrically connected to the camera MCU  42  through the main PCB  40 . Also, the third interface  823  may be electrically connected to the second cable  802 . 
     In addition, the signal processing module  800  includes a second housing  810  including an upper cover  811  and a lower cover  812 . The main PCB  40  is accommodated in the second housing  810 . 
     The second housing  810  may be manufactured in a substantially rectangular box shape. 
     A second groove  812   a  through which the first cable  801  can pass is formed on one side of the lower cover  812 , and a third groove  812   b  through which the second cable  802  can pass may be formed at the other side of the lower cover  812 . When the signal processing module  800  is assembled, the first cable  801  may be connected to the main PCB  40  through a second groove  812   a , and the second cable  802  may be connected to the main PCB  40  through a third groove  812   b.    
       FIG. 12  schematically illustrates another example of the camera system according to the second embodiment. 
     Referring to  FIG. 12 , the camera system  1  may include a plurality of camera modules  701 ,  702 ,  703  and one signal processing module  800 . 
     For example, the camera system  1  may include a plurality of camera modules  701 ,  702 , and  703  that capture different regions. The camera system  1  may include a first camera module  701  for capturing the front side of the vehicle, a second camera module  702  for capturing the left side of the vehicle, and a third camera module  703  for capturing the right side of the vehicle. 
     As another example, the camera system  1  may include a plurality of camera modules  701 ,  702 , and  703  having different viewing angles. The camera system  1  may include a first camera module  701  including a wide-angle lens having a predetermined range of viewing angle, a second camera module  702  including a telephoto lens capable of capturing a distant target, and a third camera module  703  including an ultra-wide-angle lens with an ultra-wide viewing angle exceeding 180°. A focal length of the first camera module  701  is different from the a focal length of the second camera module  702  and a focal length of the third camera module  703 . 
     As another example, the camera system  1  may include a stereo camera module for measuring a distance to an object. The camera system  1  includes a first camera module  701  for capturing the front of the vehicle, and a second camera module  702  for capturing the front of the vehicle from the left (or right) of the first camera module  701 . 
       FIG. 13  illustrates an example in which the camera system according to the second embodiment is mounted on a vehicle. 
     Referring to  FIG. 13 , the camera module  700  may be directly mounted inside the vehicle under the windshield  200  in the vehicle. Accordingly, the camera module  700  may be used to capture a field of view in the front of the vehicle, and may be used to recognize an object existing in the field of view of the front. Also, in case of rain or dust present, the camera module  700  may be mounted inside the vehicle corresponding to an area cleaned by a wiper driven outside the windshield  200 . Meanwhile, the position where the camera module  700  is mounted is not limited thereto. The camera module  700  may be installed at different locations to capture the front, side, and rear of the vehicle. 
     The first cable  801  connected to the camera module  700  may extend to the ceiling of the cabin through the upper side of the camera module  700 . 
       FIG. 14  illustrates another example in which the camera system according to the second embodiment is mounted on a vehicle.  FIG. 15  schematically illustrates a mounting module and a camera module according to the second embodiment.  FIG. 16  illustrates an example in which the camera module according to the second embodiment is combined with the mounting module.  FIG. 17  illustrates another example in which the camera module according to the second embodiment is combined with the mounting module.  FIG. 18  illustrates another example in which the camera module according to the second embodiment is combined with the mounting module. 
     Referring to  FIGS. 14 and 15 , the camera module  700  may be mounted inside the vehicle under the windshield  200  through the mounting module  900  in the vehicle. 
     The mounting module  900  may be attached to the windshield  200  of the vehicle, so that the camera module  700  may be fixed to the windshield  200  of the vehicle. 
     The mounting module  900  includes an inclined surface  901  in contact with the windshield  200  of the vehicle, and a first recess  910  for securing a field of view of the camera module  700  is formed at an approximately central portion of the inclined surface  901 . 
     The first recess  910  of the mounting module  900  may be formed by the bottom surface  911 , the side wall  913 , and the rear wall  913 . In the rear wall  913 , a second opening  913   a  is formed so that the subject image can reach the camera module  700 . When the camera module  700  is mounted on the mounting module  900 , the lens  10  of the camera module  700  may be exposed to the outside through the second opening  913   a.    
     The bottom surface  911  and the side wall  912  may be provided so as not to block the field of view of the camera module  700 . In other words, the bottom surface  911  and the side wall  912  may be formed outside the field of view of the camera module  700 . 
     In addition, on the bottom surface  911  and the side wall  912 , a light blocking member for preventing light from an external light source (e.g., the sun or a street light) from entering the camera module  700  may be formed. 
     A second recess  920  into which the camera module  700  is inserted is formed on the rear surface  902  of the mounting module  900  as shown in  FIGS. 16, 17 and 18 . For example, the camera module  700  may be coupled to the second recess  920  in a sliding method or a snap-fit method. 
     In addition, a fourth groove  902   a  into which a first cable  801  electrically connecting the camera module  700  and the signal processing module  800  is inserted may be formed on the upper side of the second recess  920 . Since the first cable  801  is connected to the camera module  700  through the upper surface of the first housing  710 , the fourth groove  902   a  may be provided on the upper side of the second recess  920 . 
     The camera module  700  may be mounted on the mounting module  900  by being inserted into the second recess  920  from the rear of the mounting module  900  toward the front. 
     When the camera module  700  is not aligned with the mounting module  900 , the field of view of the camera module  700  may be narrowed. For example, when the lens  10  of the camera module  700  is not aligned with the second opening  913   a  of the mounting module  900 , the field of view of the camera module  700  may be narrowed. 
     In order to prevent this, a guide member for guiding the mounting of the camera module  700  to the mounting module  900  may be provided in each of the mounting module  900  and the camera module  700 . 
     For example, as shown in  FIG. 16 , guide protrusions  731  and  732  may be provided on the side walls of the first housing  710  of the camera module  700 , and guide grooves  931  and  932  may be provided on the inner wall of the second recess  920  of the mounting module  900  so that the camera module  700  is aligned with the mounting module  900 . 
     The guide protrusions  731  and  732  may include a first guide protrusion  731  and a second guide protrusion  732  provided on the left and right side walls of the camera module  700 , respectively. The guide grooves  931  and  932  may include a first guide groove  931  and a second guide groove  932  provided on the left and right inner walls of the second recess  920 , respectively. 
     The guide protrusions  731  and  732  may extend in a direction in which the camera module  700  is inserted into the mounting module  900  on the left and right side walls of the camera module  700 , that is, from the rear toward the front. The guide grooves  931  and  932  may extend in a direction in which the camera module  700  is inserted into the mounting module  900  on the left and right inner walls of the second recess  920 , that is, from the rear toward the front. 
     The camera module  700  may be inserted into the second recess  920  so that the first guide protrusion  731  is inserted into the first guide groove  931  and the second guide protrusion  732  is inserted into the second guide groove  932 . The camera module  700  may be inserted into the second recess  920  in the sliding method. 
     Snap protrusions may be formed on the first and second guide protrusion  731  and  732 , and snap grooves may be formed on the first and second guide grooves  931  and  932 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  in the snap-fit method. 
     Snap grooves may be formed on the first and second guide protrusions  731  and  732 , and snap protrusions may be formed on the first and second guide grooves  931  and  932 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  along the guide grooves  931  and  932  in the snap-fit method. 
     Snap protrusions may be formed on the side walls of the first housing  710  of the camera module  700 , and snap grooves may be formed on the inner wall of the second recess  920  of the mounting module  900 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  in the snap-fit method. 
     Snap grooves may be formed on the side walls of the first housing  710  of the camera module  700 , and snap protrusions may be formed on the inner wall of the second recess  920  of the mounting module  900 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  along the guide grooves  931  and  932  in the snap-fit method. 
     As another example, as shown in  FIG. 17 , guide protrusions  933  and  934  may be provided on the inner wall of the second recess  920  of the mounting module  900  and guide grooves  733  and  734  may be provided on a side wall of the first housing  710  of the camera module  700  so that the camera module  700  is aligned with the mounting module  900 . 
     The guide grooves  733  and  734  may include a third guide groove  733  and a fourth guide groove  734  provided on left and right side walls of the camera module  700 , respectively. The guide protrusions  933  and  934  may include a third guide protrusion  933  and a fourth guide protrusion  934  provided on the left and right inner walls of the second recess  920 , respectively. 
     The guide grooves  733  and  734  may extend in a direction in which the camera module  700  is inserted into the mounting module  900  on the left and right side walls of the camera module  700 , that is, from the rear toward the front. The guide protrusions  933  and  934  may extend in a direction in which the camera module  700  is inserted into the mounting module  900  on the left and right inner walls of the second recess  920 , that is, from the rear toward the front. 
     The camera module  700  may be inserted into the second recess  920  so that the third guide protrusion  933  is inserted into the third guide groove  733  and the fourth guide protrusion  934  is inserted into the fourth guide groove  734 . The camera module  700  may be inserted into the second recess  920  along the guide protrusions  933  and  934  in the sliding method. 
     Snap protrusions may be formed on the third and fourth guide grooves  733  and  734 , and snap grooves may be formed on the third and fourth guide protrusions  933  and  934 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  along the guide protrusions  933  and  934  in the snap-fit method. 
     Snap grooves may be formed on the third and fourth guide grooves  733  and  734 , and snap protrusions may be formed on the third and fourth guide protrusions  933  and  934 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  along the guide protrusions  933  and  934  in the snap-fit method. 
     Snap protrusions may be formed on the side walls of the first housing  710  of the camera module  700 , and snap grooves may be formed on the inner wall of the second recess  920  of the mounting module  900 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  along the guide protrusions  933  and  934  in the snap-fit method. 
     Snap grooves may be formed on the side walls of the first housing  710  of the camera module  700 , and snap protrusions may be formed on the inner wall of the second recess  920  of the mounting module  900 . The snap grooves may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The snap protrusions may extend in a direction perpendicular to a direction in which the camera module  700  is inserted into the second recess  920 . The camera module  700  may be inserted into the second recess  920  along the guide protrusions  933  and  934  in the snap-fit method. 
     As another example, as shown in  FIG. 18 , the camera module  700  may be mounted on the mounting module  900  by being inserted into the second recess  920  from the lower side toward the upper side of the mounting module  900 . 
     Fifth and sixth guide protrusions  735  and  736  may be provided on the side walls of the first housing  710  of the camera module  700 , and fifth and sixth guide grooves  935  and  936  may be provided on the inner wall of the second recess  920  of the mounting module  900  so that the camera module  700  is aligned with the mounting module  900 . 
     The fifth and sixth guide protrusions  735  and  736  may extend in a direction in which the camera module  700  is inserted into the mounting module  900  on the left and right side walls of the camera module  700 , that is, from the lower side toward the upper side. The guide grooves  935  and  936  may extend in a direction in which the camera module  700  is inserted into the mounting module  900  on the left and right inner walls of the second recess  920 , that is, from the lower side toward the upper side. 
     The camera module  700  may be inserted into the second recess  920  so that the fifth guide protrusion  735  is inserted into the fifth guide groove  935  and the sixth guide protrusion  736  is inserted into the sixth guide groove  936 . 
     Third Embodiment 
     For autonomous driving beyond driving assistance, collision avoidance between a host vehicle and nearby vehicles should be guaranteed. A conventional emergency braking system may calculate a relative speed and a relative acceleration of the host vehicle with respect to each forward collision risk factor, check the time-to-collision, and perform braking control on the host vehicle to avoid the collision. However, in order to avoid a collision with a vehicle ahead, only a vertical (acceleration or deceleration) control has been performed, and thus when a dangerous situation occurs, there is a limitation on avoidance of the collision with the vehicle ahead. 
     The third embodiment of the present disclosure relates to a camera system for an ADAS and a collision prevention system and method which are capable of determining a risk of collision with a nearby vehicle, detecting a target vehicle with a collision risk, controlling the speed and steering of the host vehicle, and avoiding the collision with the target vehicle. 
     The third embodiment of the present disclosure will be described below with reference to  FIGS. 19 to 22 . 
       FIG. 19  is a diagram showing a collision prevention system according to a third embodiment of the present disclosure. 
     Referring to  FIG. 19 , the collision prevention system according to the third embodiment of the present disclosure includes a camera system  1 , a radar system  2 - 2 , an ECU  2 - 320 , a vehicle posture controller  2 - 333 , a steering controller  2 - 334 , an engine controller  2 - 335 , a suspension controller  2 - 336 , and a brake controller  2 - 337 . Each of the controllers  2 - 222 ,  2 - 334 ,  2 - 335 ,  2 - 336 , and  2 - 337  controls a corresponding component of the vehicle on the basis of a control command received from the ECU  2 - 320 . 
     The camera system  1  includes one or more cameras, an image processor  41 , and a camera MCU  42 . The camera system  1  generates image data regarding regions ahead of, behind, to the left of, and to the right of the host vehicle and transmits the generated image data to the ECU  2 - 320 . 
     The radar system  2 - 2  includes one or more radars and a radar MCU  2 - 312 . The radar system  2 - 2  emits radio waves to the regions ahead, behind, to the left, and to the right and receives reflected waves to detect objects located in the regions ahead, behind, to the left, and to the right within a distance of 150 meters and a horizontal angle of 30 degrees. Here, the radar system  2 - 2  detects the objects using FMCW and Pulse Carrier and transmits radar data including a result of detecting the objects to the ECU  2 - 320 . 
     The ECU  2 - 320  detects a target vehicle from among nearby vehicles on the basis of the image data input from the camera system  1  and the radar data input from the radar system  2 - 2  and determines a risk of collision between the host vehicle and the target vehicle. Here, the image data transmitted from the camera system  1  to the ECU  2 - 320  includes lane recognition information, vehicle-in-front recognition information, vehicle-behind recognition information, vehicle-to-the-left recognition information, and vehicle-to-the-right recognition information. Also, the radar data transmitted from the radar system  2 - 2  to the ECU  2 - 320  includes vehicle-in-front recognition information, vehicle-behind recognition information, vehicle-to-the-left recognition information, and vehicle-to-the-right recognition information. 
     When it is determined that there is a risk of collision between the host vehicle and the target vehicle, a control signal is transmitted to the vehicle posture controller  2 - 333 , the steering controller  2 - 334 , the engine controller  2 - 335 , the suspension controller  2 - 336 , and the brake controller  2 - 337  in order to avoid the collision. In this way, the posture, speed, and steering of the host vehicle are controlled to avoid the collision between the host vehicle and the target vehicle. 
     By controlling the steering controller  2 - 334 , the engine controller  2 - 335 , and the brake controller  2 - 337 , the collision with the target vehicle may be avoided. In order to prevent a reduction of ride quality due to a significant change in speed or steering of the host vehicle and prevent an accident due to a driver&#39;s posture instability, the vehicle posture controller  2 - 333  and the suspension controller  2 - 336  are also controlled to ensure driving stability along with collision avoidance. 
       FIG. 20  is a diagram showing a method of detecting a target vehicle with a collision risk according to the third embodiment of the present disclosure. 
     Referring to  FIG. 20 , the ECU  2 - 320  corrects signals of the image data input from the camera system  1  and the radar data input from the radar system  2 - 2  (lateral offset, angle, target lateral speed). 
     The ECU  2 - 320  detects, as a target vehicle B, a vehicle overlapping a host vehicle A by a certain percentage or higher from among nearby vehicles. As an example, the ECU  2 - 320  may detect a vehicle overlapping the host vehicle A by 50% or higher as the target vehicle B. 
     Also, the ECU  2 - 320  detects a nearby vehicle having a traveling angle that differs from that of the host vehicle A by a certain degree or less as the target vehicle B. As an example, when the angle difference between the host vehicle A and the nearby vehicle ranges 0% to 30%, the ECU  2 - 320  may detect the nearby vehicle as the target vehicle B. Here, the ECU  2 - 320  detects, as the target vehicle B, a nearby vehicle (or object) overlapping the host vehicle A by a certain percentage or higher or having an angle that differs from that of the host vehicle A by a certain degree or less, irrespective of whether the vehicle (or object) is stopped or is traveling. 
     The ECU  2 - 320  detecting the target vehicle B has been described above. However, a collision with a pedestrian or an object as well as a vehicle should be avoided, and thus the ECU  2 - 320  detects a target object (including a target vehicle) and controls the host vehicle A to avoid a collision with the target object. That is, when an object (including a vehicle and a pedestrian) is detected on a traveling direction route of the host vehicle A, the ECU  2 - 320  detects the detected object as the target object. Here, the traveling route of the host vehicle A may be set on the basis of lanes. When a road has no lanes, the ECU  2 - 320  may generate a virtual lane and detect a target object on the traveling route on the basis of the virtual lane and the location of the nearby object. In particular, when a new object cuts into the traveling route, the ECU  2 - 320  detects this object as the target object (or target vehicle). 
       FIG. 21  is a diagram showing a method of avoiding a collision with a target vehicle by controlling the speed and steering of a host vehicle according to the third embodiment of the present disclosure. 
     Referring to  FIG. 21 , a collision risk is calculated on the basis of a lateral offset between a host vehicle and a target vehicle as represented in the following Equation 1. 
       Lateral offset=lateral speed of target object*TTC=(relative distance)/(relative speed)  (Equation 1)
 
     Dynamic control: lateral offset (TTC, Vlat)&lt;X 
     Deceleration+avoidance control: X1&lt;lateral offset (TTC, Vlat)&lt;X2 
     No control required: lateral offset (TTC, Vlat) &gt;X3 
     ECU  2 - 320  calculates a heading angle and a lateral offset and performs update. Also, the ECU  2 - 320  maintains a lane curvature and a curvature derivative. 
     When the risk of collision between the host vehicle and the target vehicle exceeds a pre-determined reference value, the ECU  2 - 320  generates an avoidance route in consideration of an expected heading angle (HA) and controls the speed and steering of the host vehicle. In this case, the ECU  2 - 320  may generate a steering avoidance route on the basis of a three-dimensional (3D) lane-based model. 
     3D lane-based model Y=C0I+C1IX+C2IX2+C3IX3 
     C0I indicates a lateral offset (Lane Mark Position), C1I indicates a line heading angle (Lane Mark Heading Angle), 2C2I indicates a line curvature (Lane Mark Model A), 6C3I indicates a line curvature derivative (Lane Mark Model d(A)). 
     Steering Control Collision Avoidance 
     When a collision is avoided through steering control, the ECU  2 - 320  transmits a control signal to the steering controller  2 - 334  and controls the steering of the host vehicle A. Here, when the steering of the host vehicle A is controlled in order to avoid a collision with the target vehicle B, a collision with a nearby vehicle approaching behind may occur. According to the present disclosure, before performing steering avoidance control, the ECU  2 - 320  determines a risk of collision with a vehicle approaching behind or a vehicle traveling in the left or right lane. 
     When there is no risk of collision with a vehicle traveling behind and there is no vehicle traveling in the left or right lane or no risk of collision with a vehicle traveling in the left or right lane, the ECU  2 - 320  controls the steering of the host vehicle A to avoid the collision with the target vehicle B. 
     Also, when a collision with the target vehicle B ahead is expected to occur and it is determined that the collision can be avoided only by decelerating the host vehicle A, the ECU  2 - 320  may control the steering of the host vehicle A to avoid the collision with the target vehicle B. 
     Speed Control Collision Avoidance 
     When a collision is avoided through speed control, the ECU  2 - 320  transmits a control signal to the engine controller  2 - 335  and the brake controller  2 - 337  to decelerate the host vehicle A. Here, when a collision with the target vehicle B ahead is expected, the ECU  2 - 320  determines a risk of collision with a vehicle traveling in the left or right lane upon the steering avoidance. When the collision with the vehicle traveling in the left or right lane is determined upon the steering avoidance, the ECU  2 - 320  decelerates the host vehicle A to avoid the collision with the target vehicle B. 
     Also, when a collision with the target vehicle B ahead is expected and it is determined that the collision can be avoided by decelerating the host vehicle A, the ECU  2 - 320  may decelerate the host vehicle A to avoid the collision with the target vehicle B. 
     Collision Avoidance Upon Land Change of Vehicle in the Next Lane 
     A method of preventing a collision when a vehicle traveling in the next lane enters (cuts into) a traveling route of the host vehicle will be described. 
     As an example, by the ECU  2 - 320  analyzing image data obtained by capturing vehicles traveling in the next lane, the camera system  1  senses lane change intentions of the vehicles traveling in the next lane. The ECU  2 - 320  may detect turn signal lights (blinkers) of nearby vehicles to detect that a vehicle traveling in the next lane enters (cuts into) the traveling route of the host vehicle A. 
     As another example, by the ECU  2 - 320  analyzing image data obtained by capturing vehicles traveling in the next lane, the camera system  1  senses lane change intentions of the vehicles traveling in the next lane. The ECU  2 - 320  may detect tire orientations of nearby vehicles to detect that a vehicle traveling in the next lane enters (cuts into) the traveling route of the host vehicle A. 
     As still another example, the ECU  2 - 320  analyzes image data obtained by the camera system  1  capturing the vehicles traveling in the next lane and radar data obtained by the radar system  2 - 2  detecting the vehicles traveling in the next lane. In this way, the ECU  2 - 320  senses the lane change intentions of the vehicles traveling in the next lane. The ECU  2 - 320  may detect lateral accelerations and directions of nearby vehicles to detect that a vehicle traveling in the next lane enters (cuts in) the traveling route of the host vehicle A. 
     
       
         
           
               
               
             
               
                 TABLE 1 
               
               
                   
               
             
            
               
                 Acceleration of  
                 Relative speed with respect to vehicle traveling in 
               
               
                 host vehicle 
                 next lane &lt; V 
               
               
                   
                 Longitudinal distance with respect to vehicle  
               
               
                   
                 traveling in next lane &lt; Y 
               
               
                   
                 Lateral distance with respect to vehicle traveling in 
               
               
                   
                 next lane &lt; X 
               
               
                 Deceleration of  
                 Speed of vehicle traveling in next lane &lt; Speed of 
               
               
                 host vehicle 
                 host vehicle + α 
               
               
                   
                 Longitudinal distance with respect to vehicle  
               
               
                   
                 traveling in next lane &gt; Y 
               
               
                   
                 Lateral distance with respect to vehicle traveling in 
               
               
                   
                 next lane &gt; X 
               
               
                 Braking of  
                 Speed of host vehicle &gt; Speed of vehicle traveling in 
               
               
                 host vehicle 
                 next lane 
               
               
                   
                 Longitudinal distance with respect to vehicle  
               
               
                   
                 traveling in next lane &lt; Y 
               
               
                   
                 Lateral distance with respect to vehicle traveling in 
               
               
                   
                 next lane &lt; X 
               
               
                 Host vehicle  
                 Speed of host vehicle &gt; Speed of vehicle traveling in 
               
               
                 steering 
                 next lane 
               
               
                 avoidance 
                 Longitudinal distance with respect to vehicle  
               
               
                   
                 traveling in next lane &lt; Y 
               
               
                   
                 X1 &lt; Lateral distance with respect to vehicle  
               
               
                   
                 traveling in next lane &lt; X2 
               
               
                   
                 Case in which there is no vehicle in next lane 
               
               
                   
                 Lateral distance from avoidance direction lane to 
               
               
                   
                 vehicle ahead being greater than or equal to certain 
               
               
                   
                 value 
               
               
                   
               
            
           
         
       
     
     When a vehicle traveling in the next lane enters (cuts into) the traveling route of the host vehicle A, when a vehicle in the right lane cuts ahead of the host vehicle A upon a left turn at an intersection, or when a vehicle in the left lane cuts ahead of the host vehicle A upon a right turn at an intersection, as shown in Table 1, the ECU  2 - 320  determines a control mode of the host vehicle A. The ECU  2 - 320  may avoid a collision between the host vehicle A and a nearby vehicle through one of or a combination of an acceleration control mode, a deceleration control mode, a braking control mode, and a steering control mode. As an example, the ECU  2 - 320  may avoid the collision by performing acceleration control, deceleration control, braking control, or steering control on the host vehicle A. Here, the acceleration control and the steering control may be simultaneously performed on the host vehicle A, the acceleration control and the steering control may be simultaneously performed on the host vehicle A, and the braking control and the steering control may be simultaneously performed on the host vehicle A. 
       FIG. 22  is a diagram showing the collision avoidance method according to the third embodiment of the present disclosure. 
     Referring to  FIG. 22 , the ECU  2 - 320  receives image data generated by the camera system  1  and radar data generated by the radar system  2 - 2  (S 2 - 10 ). 
     Subsequently, the ECU  2 - 320  corrects signals of the image data and the radar data. That is, the ECU  2 - 320  corrects sensor signals (S 2 - 20 ). 
     Subsequently, the ECU  2 - 320  detects a target vehicle from among nearby vehicles on the basis of the image data and the radar data (S 2 - 30 ). Here, the ECU  2 - 320  detects, as a target vehicle B, a vehicle overlapping a host vehicle A by a certain percentage or higher from among the nearby vehicles. As an example, the ECU  2 - 320  may detect a vehicle overlapping the host vehicle A by 50% or higher as the target vehicle B. Also, the ECU  320  detects a nearby vehicle having a traveling angle that differs from that of the host vehicle A by a certain degree or less as the target vehicle B. As an example, when the angle difference between the host vehicle A and the nearby vehicle ranges 0% to 30%, the ECU  2 - 320  may detect the nearby vehicle as the target vehicle B. The ECU  2 - 320  detects, as the target vehicle B, a nearby vehicle (or object) overlapping the host vehicle A by a certain percentage or higher or having an angle that differs from that of the host vehicle A by a certain degree or less, irrespective of whether the nearby vehicle (or object) is stopped or is traveling. 
     Subsequently, the ECU  2 - 320  determines a risk of collision between the host vehicle and the target vehicle on the basis of a lateral offset between the host vehicle and the target vehicle (S 2 - 40 ). 
     Subsequently, when the collision between host vehicle and the target vehicle is determined, the ECU  2 - 320  determines a control mode of the host vehicle and transmits a control signals to the vehicle posture controller  2 - 333 , the steering controller  2 - 334 , the engine controller  335 , the suspension controller  2 - 336 , and the brake controller  2 - 337  according to the determined control mode. In this way, the posture, speed, and steering of the host vehicle are controlled to avoid the collision between the host vehicle and the target vehicle. 
     Here, the collision with the target vehicle may be avoided by controlling the steering of the host vehicle. Also, the collision with the target vehicle may be avoided by controlling the speed of the host vehicle. Also, a collision between the host vehicle and a vehicle cutting in from the next lane may be avoided by controlling one or more of the speed, braking, and steering of the host vehicle when the vehicle traveling in the next lane changes lanes. 
     Fourth Embodiment 
     At an intersection, a host vehicle may go straight, turn around, or turn left or right and may change lanes in order to turn around or turn left or right. Also, vehicles other than the host vehicle may also turn around or turn left or right, and thus there is a high possibility of a collision between vehicles. To this end, a vehicle needs a control system for preventing a vehicle collision and a variety of sensors for sensing a collision. 
     The fourth embodiment of the present disclosure relates to a driving assistance system that controls a vehicle using a camera system for an ADAS. 
     The fourth embodiment of the present disclosure will be described below with reference to  FIGS. 13 to 15 . 
       FIG. 23  is a diagram showing vehicle control according to the fourth embodiment of the present disclosure. 
     Referring to  FIGS. 1, 3, and 23 , a camera system  1  and/or a GPS processor  3 - 313  may discover that a vehicle  3 - 1000  enters an intersection. The camera system  1  may discover a traffic light  3 - 1100  of the intersection to discover that the vehicle  3 - 1000  enters the intersection. The GPS processor  3 - 313  may measure the location of the vehicle  3 - 1000  through communication with a satellite, compare the measured location to prestored map information, and determine whether the vehicle  3 - 1000  enters the intersection. 
     The camera system  1  may capture state information of the surroundings of the vehicle  3 - 1000 , first information, and second information and transmit the captured information to the ECU  3 - 320 . The ECU  3 - 320  may receive the state information, the first information, and the second information and control the steering of the vehicle  3 - 1000  on the basis of the received information. The state information may include at least one of an expanded branch lane and road marks  3 - 1210  and  3 - 1230 . The first information may include at least one of data regarding vehicles ahead, data regarding lanes ahead, distances from font vehicles, data regarding traffic signs of an intersection, and signal data of an intersection. The second information may include a left-turn road mark  3 - 1250  of the branch lane  3 - 1130 , an intersection stop line  3 - 1270 , the presence of a vehicle ahead, and intersection signal data. The expanded branch lane  3 - 1130  may refer to a lane which the vehicle  3 - 1000  traveling in a left hand lane  3 - 1110  (the leftmost lane with respect to a vehicle traveling direction) will enter in order to turn left. That is, the expanded branch lane  3 - 1130  may refer to a lane that is newly provided to the left of the left hand lane  3 - 1110 . The first information may be information discovered by the camera system  1  before or while the vehicle  3 - 1000  enters the branch lane  3 - 1130 , and the second information may be information discovered by the camera system  1  after the vehicle  3 - 1000  enters the branch lane  3 - 1130 . 
     As an example, the camera system  1  may capture a region ahead of the vehicle  3 - 1000  or sense the road marks  3 - 1210  and  3 - 1230  present ahead of the vehicle  3 - 1000  to discover whether there is a branch lane. For example, the road marks  3 - 1210  and  3 - 1230  may include a safety zone mark  3 - 1210  displayed for the branch lane on a road and a guidance mark  3 - 1230  representing a vehicle traveling direction. The guidance mark  3 - 1230  may inform a driver that the vehicle  3 - 1000  may enter the branch lane  3 - 1130 . 
     As an example, before or while the vehicle  3 - 1000  enters the branch lane  3 - 1130 , the camera system  1  may discover whether a lane ahead of the vehicle  3 - 1000  is empty, whether another vehicle is present ahead, a distance from a vehicle ahead, and the like. Thus, it is possible for the vehicle  3 - 1000  to avoid colliding with a vehicle ahead while entering the branch lane  3 - 1130 . Also, after the vehicle  3 - 1000  enters the branch lane  3 - 1130 , the camera system  1  may discover the left-turn road mark  3 - 1250 , the intersection stop line  3 - 1270 , data regarding traffic signs of the intersection, and the intersection signal data. 
     The ECU  3 - 320  may control some of the elements in the control level on the basis of the state information, the first information, and the second information. As an example, the ECU  3 - 320  may control the steering controller  3 - 334  using the state information to control the steering of the vehicle  3 - 1000 . Through information regarding the expanded branch lane and the road marks  3 - 1210  and  3 - 1230 , the ECU  3 - 320  may control the steering such that the vehicle  3 - 1000  traveling in the left-hand lane  3 - 1110  enters the branch lane  3 - 1130 . Also, the ECU  3 - 320  may control the speed and braking of the vehicle  3 - 1000  using the first information. In this case, the ECU  3 - 320  may control an engine controller  3 - 335 , a suspension controller  3 - 336 , a brake controller  3 - 337 , and the like. When the vehicle  3 - 1000  enters the branch lane  3 - 1130 , the ECU  3 - 320  may prevent a collision with a vehicle ahead using the first information, which includes data regarding vehicles ahead, data regarding lanes ahead, and distances from vehicles ahead. For example, when a distance from a vehicle ahead is smaller than a pre-determined distance or when a vehicle ahead travels at low speed, the ECU  3 - 320  may decelerate the vehicle  3 - 1000  or operate the brake. 
     As an example, after the vehicle  3 - 1000  enters the branch lane  3 - 1130 , the ECU  3 - 320  may determine whether to stop or turn left at an intersection through the second information, which includes the left-turn road mark  3 - 1250 , the intersection stop line  3 - 1270 , the data regarding traffic signs of the intersection, and the intersection signal data and then may control the vehicle  3 - 1000 . For example, when the intersection signal data indicates turning on a left-turn signal, the camera system  1  may recognize the intersection signal data and the left-turn road mark  3 - 1250 . The ECU  3 - 320  may receive information regarding the left-turn road mark  3 - 1250  and the intersection signal data from the camera system  1  and control the vehicle  3 - 1000  located in the branch lane  3 - 1130  to turn left. When the intersection signal data indicates turning off a left-turn signal, the ECU  3 - 320  may control the vehicle  3 - 1000  to stop before the intersection stop line  3 - 1270  or may control the vehicle  3 - 1000  to stop away from another vehicle ahead of the vehicle  3 - 1000 . In this case, the ECU  3 - 320  may control the steering controller  3 - 334 , the engine controller  3 - 335 , the suspension controller  3 - 336 , the brake controller  3 - 337 , and the like. However, the control of the vehicle  3 - 1000  through the ECU  3 - 320  according to the present disclosure may not be limited to the above examples. 
     As another example, the data regarding the vehicles ahead, the data regarding the lanes ahead, and the distance from the vehicle ahead may be discovered through a Lidar and a radar. The camera system  1  may interoperate with the lidar and the radar to discover information regarding the surroundings of the vehicle and to transmit the information to the ECU  3 - 320 . 
     The ECU  3 - 320  may control a driver warning controller  3 - 331  to inform a driver of whether the vehicle  3 - 1000  can enter the branch lane  3 - 1130 , whether a left-turn is allowed in the branch lane  3 - 1130 , and the like. The driver warning controller  331  may display a video-type notification message or a notification image to the driver through an HUD or a side mirror display or may inform the driver in an audio manner. Through the information provided by the driver warning controller  3 - 331 , the driver may directly change the steering of the vehicle  3 - 1000  or may control the overall configuration of the vehicle  3 - 1000 . 
       FIG. 24  is a flowchart illustrating the order of controlling a vehicle according to the fourth embodiment of the present disclosure. 
     Referring to  FIGS. 1, 6, and 24 , the ECU  3 - 320  may determine whether the vehicle  3 - 1000  is approaching an intersection on the basis of location information of the vehicle  3 - 1000  and information of the intersection by using a GPS apparatus. Also, the ECU  3 - 320  may discover a traffic light  3 - 1100  of the intersection using the camera system  1  to determine whether the vehicle  3 - 1000  is approaching the intersection (S 3 - 10 ). 
     The camera system  1  may discover state information of the surroundings of the vehicle. For example, the state information may include at least one of the expanded branch lane and the road marks  3 - 1210  and  3 - 1230  (S 3 - 20 ). Additionally, the camera system  1  may discover the first information, which is information regarding the region ahead of the vehicle  3 - 1000 . For example, the first information may include at least one of the data regarding vehicles ahead, the data regarding lanes ahead, the distances from the font vehicles, the data regarding the traffic signs of the intersection, and the intersection signal data (S 3 - 30 ). 
     The camera system  1  may transmit the state information and the first information to the ECU  3 - 320 , and the ECU  3 - 320  may determine whether the vehicle  3 - 1000  can make a lane change from the left hand lane  3 - 1110  to the branch lane  3 - 1130  on the basis of the state information and the first information. First, the ECU  3 - 320  may determine whether the branch lane  3 - 1130  is present on the basis of the state information. When it is determined that the branch lane  3 - 1130  is present, the ECU  3 - 320  may determine a possibility of the vehicle  3 - 1000  colliding with another vehicle ahead on the basis of the first information. When it is determined through the state information that the safety zone mark  3 - 1210  and the guidance mark  3 - 1230  are present to the left of the left hand lane  3 - 1110 , the ECU  3 - 320  may control the steering of the vehicle  3 - 1000  to make a lane change to a lane allowing a left-turn, that is, the branch lane  3 - 1130 . In this case, the ECU  3 - 320  may control the vehicle  3 - 1000  to prevent a collision with another vehicle in consideration of the first information. When it is determined in consideration of the first information that there is a possibility of colliding with a vehicle ahead, the ECU  3 - 320  may not enter the branch lane  3 - 1130 , the camera system  1  may rediscover first information and transmit the first information to the ECU  3 - 320 , and the ECU  3 - 320  may determine whether there is a possibility of colliding with a vehicle ahead again (S 3 - 45 , S 3 - 50 ). 
     As another example, when it is determined through the state information that there are no safety zone mark  3 - 1210  and no guidance mark  3 - 1230  to the left of the left hand lane  3 - 1110 , the ECU  3 - 320  may not control the steering of the vehicle  3 - 1000 . That is, the ECU  3 - 320  may control the vehicle  3 - 1000  not to enter the branch lane  3 - 1130 . 
       FIG. 25  is a flowchart illustrating the order of controlling a vehicle according to the fourth embodiment of the present disclosure. 
     Referring to  FIGS. 1, 6, and 25 , the camera system  1  may discover the second information regarding a region ahead of the vehicle  3 - 1000  having made a lane change to the left lane. The second information may include the left-turn road mark  3 - 1250  of the branch lane  3 - 1130 , the intersection stop line  3 - 1270 , the presence of a vehicle ahead, and the intersection signal data (S 3 - 50 , S 3 - 60 ). The camera system  1  may transmit the second information to the ECU  3 - 320 , and the ECU  3 - 320  may control the speed and braking of the vehicle  3 - 1000  on the basis of the intersection stop line  3 - 1270  and the presence of a vehicle ahead. For example, when another vehicle is present ahead of the vehicle  3 - 1000 , the ECU  3 - 320  may perform control to decelerate the vehicle  3 - 1000  or to drive the brake. When there is no other vehicle ahead of the vehicle  3 - 1000 , the ECU  3 - 320  may control the speed and braking of the vehicle  3 - 1000  in order to stop at the intersection stop line  3 - 1270  (S 3 - 70 ). When the intersection signal is a “Go” signal allowing a left turn, the ECU  3 - 320  may control the vehicle  3 - 1000  to turn left. When the intersection signal is not a “Go” signal allowing a left turn, the camera system  1  may rediscover second information, and the ECU  3 - 320  may control the vehicle  3 - 1000  on the basis of the second information. The ECU  3 - 320  may control a driver warning controller to inform the driver of whether the vehicle can turn left, which is determined through the state information, the first information, and the second information (S 3 - 80 , S 3 - 90 ). 
     Fifth Embodiment 
     The emergency braking system provides collision warning and automatic braking control when a collision with a vehicle ahead or pedestrian is expected. To this end, the emergency braking system calculates a relative speed and acceleration of the host vehicle with respect to each collision risk factor ahead, checks the time-to-collision, and determines a braking control start time of the host vehicle. However, an emergency braking system according to the related art determines the braking control start time of the host vehicle without considering a road condition. When it comes to rain or snow, a road becomes slippery, and the braking distance increases compared to a normal road. Accordingly, it is assumed that a braking control start time set on the basis of a normal road is applied to a slippery road. In this case, even when an emergency braking is performed, a collision with a vehicle ahead or object (including a pedestrian) cannot be avoided. 
     The fifth embodiment of the present disclosure relates to a camera system for an ADAS and an emergency braking system and method which are capable of controlling an emergency braking start time according to the degree to which a road is slippery. 
     The fifth embodiment of the present disclosure will be described below with reference to  FIGS. 26 to 28 . 
       FIG. 26  is a diagram showing an example in which a slippery road sign is recognized using a camera system according to the fifth embodiment of the present disclosure. 
     Referring to  FIG. 26 , the emergency braking system according to the fifth embodiment of the present disclosure may recognize a slippery road and may control the emergency braking start time according to the degree to which the road is slippery. Also, by advancing the emergency braking start time when it is determined that the road is slippery, it is possible to prevent a head-on/rear-end collision due to an increase in braking distance. To this end, the emergency braking system according to an embodiment of the present disclosure includes an ECU  4 - 320 , a GPS MCU  4 - 313 , a navigation MCU  4 - 314 , a driver warning controller  4 - 331 , an engine controller  4 - 335 , a brake controller  4 - 337 , and a camera system  1 . 
     As an example of recognizing a slippery road, the emergency braking system according to the fifth embodiment of the present disclosure recognizes road signs S 1  and S 2  indicating a road condition using the camera system  1  and provides a result of recognizing the road signs to the ECU  4 - 320 . As an example, the emergency braking system may recognize the road sign S 1 , which indicates a slippery road, the road sign S 2 , which indicates a wet road, etc. In addition, the emergency braking system may recognize a sign indicating a bridge inclinable to freeze, a sign indicating a habitual flooding zone, and the like. 
     As an example of recognizing a slippery road, the emergency braking system according to the fifth embodiment of the present disclosure may check a weather condition corresponding to a current road to recognize whether the road is slippery. Using the navigation MCU  4 - 314  or a smart device (e.g., a cellular phone), the emergency braking system receives current weather information corresponding to a current road and provides the weather information to the ECU  4 - 320 . 
     As an example of recognizing a slippery road, the emergency braking system according to the fifth embodiment of the present disclosure may check whether the windshield wiper of the vehicle operates. When the windshield wiper operates continuously for a certain period of time, the emergency braking system may recognize that a current road is slippery. 
     As an example of recognizing a slippery road, the emergency braking system according to the fifth embodiment of the present disclosure may check a road condition by analyzing a road image because moisture remains on the road in the case of rain or snow. Using the camera system  1 , the emergency braking system captures a region ahead of a current road and recognizes a road condition from the image regarding the region ahead. The camera system  1  provides information regarding the road condition to the ECU  4 - 320 . 
     Emergency Braking Control on Normal Road 
       FIG. 27  is a diagram showing an example in which an emergency braking system changes an emergency braking start time according to a degree to which a road is slippery according to the fifth embodiment of the present disclosure. 
     Referring to  FIG. 27 , when it is determined that a host vehicle is traveling on a normal road, the ECU  4 - 320  maintain a default value without applying a separate weight when the emergency braking start time is calculated. 
     The navigation MCU  4 - 314  computes the speed of a host vehicle V1 and calculates a relative speed between the host vehicle V1 and a target vehicle V2 on the basis of a distance between the host vehicle V1 and the target vehicle V2. Information regarding the relative speed between the host vehicle V1 and the target vehicle V2 is provided to the ECU  4 - 320 . 
     The ECU  4 - 320  calculates the time to collision (TTC) of the host vehicle V1 and the target vehicle V2 on the basis of the relative speed between the host vehicle V1 and the target vehicle V2 and sets times for a first warning A 1 , a second warning B 1 , and a third warning C 1  according to the TTC. 
     Here, the first warning A 1  is a step of pre-filling the brake with pressure. The ECU  4 - 320  controls the brake controller  4 - 337  to pre-fill the brake with pressure so that the vehicle may be braked immediately upon emergency braking. 
     The second warning B 1  is a step of decreasing/stopping the output of the engine. The ECU  4 - 320  controls the engine controller  4 - 331  to decrease or stop the output of the engine so that the vehicle may be braked immediately upon emergency braking. 
     The third warning C 1  is a step of actually performing braking. The ECU  4 - 320  controls the brake controller  4 - 337  to perform full braking. 
     In the steps for the first warning A 1 , the second warning B 1 , and the third warning C 1 , the ECU  4 - 320  controls the driver warning controller  4 - 331  to warn a driver of an emergency braking situation and to notify the driver that emergency braking is performed. Here, the ECU  4 - 320  may warn the driver of an abnormal situation by outputting warning sounds through an audio apparatus of the vehicle, visually outputting a warning situation through a video apparatus, and tactically outputting a warning situation through a haptic apparatus. 
     Emergency Braking Control on Slippery Road 
     The ECU  4 - 320  recognizes whether a current road is slippery on the basis of a result of recognizing a sign on the road. Also, the ECU  4 - 320  may check a weather condition corresponding to the current road to recognize whether the road is slippery. Also, the ECU  4 - 320  may check whether the windshield wiper of the vehicle operates and may recognize that the current road is slippery when the windshield wiper operates continuously for a certain period of time. Also, the ECU  4 - 320  may check a road condition from the image regarding the region ahead to recognize whether the current road is slippery. 
     When it is determined that the host vehicle is traveling on a slippery road, the ECU  4 - 320  advances the emergency braking control start time by applying a weight (ranging, for example, from +30% to +70%) when calculating an emergency braking start time in consideration of an increase in braking distance. 
     The navigation MCU  4 - 314  computes the speed of a host vehicle V1 and calculates a relative speed between the host vehicle V1 and a target vehicle V2 on the basis of a distance between the host vehicle V1 and the target vehicle V2. Information regarding the relative speed between the host vehicle V1 and the target vehicle V2 is provided to the ECU  4 - 320 . 
     The ECU  4 - 320  calculates the TTC of the host vehicle V1 and the target vehicle V2 on the basis of the relative speed between the host vehicle V1 and the target vehicle V2 and sets times for a first warning A 2 , a second warning B 2 , and a third warning C 2  according to the TTC. Here, the emergency braking control start time is advanced by applying a weight (ranging, for example, from +30% to +70%) when the emergency braking start time is calculated. 
     Generally, the slippery road has a braking distance greater than about 1.5 times the braking distance of a normal road. Thus, the emergency braking control start time is advanced by applying a weight of 50% when the emergency braking start time is calculated. 
     Here, the first warning A 2  is a stage of pre-filling the brake with pressure. The ECU  4 - 320  controls the brake controller  4 - 337  to pre-fill the brake with pressure so that the vehicle may be braked immediately upon emergency braking. 
     The second warning B 2  is a step of decreasing/stopping the output of the engine. The ECU  4 - 320  controls the engine controller  4 - 331  to decrease or stop the output of the engine so that the vehicle may be braked immediately upon emergency braking. 
     The third warning C 2  is a step of actually performing braking. The ECU  4 - 320  controls the brake controller  4 - 337  to perform full braking. 
     In the steps for the first warning A 1 , the second warning B 1 , and the third warning C 1 , the ECU  4 - 320  controls the driver warning controller  4 - 331  to warn a driver of an emergency braking situation and to notify the driver that emergency braking is performed. Here, the ECU  4 - 320  may warn the driver of an abnormal situation by outputting warning sounds through an audio apparatus of the vehicle, visually outputting a warning situation through a video apparatus, and tactically outputting a warning situation through a haptic apparatus. 
       FIG. 28  is a diagram showing an emergency braking method according to the fifth embodiment of the present disclosure. 
     Referring to  FIG. 28 , on the basis of recognition of a road sign, it is determined whether a current road is slippery (S 4 - 10 ). 
     When it is determined in S 4 - 10  that no road sign is recognized or that the recognized road sign does not warn of a road condition, weather information is checked to determine whether a current road is slippery (S 4 - 20 ). 
     When it is determined in S 4 - 20  that the current road is not slippery, it is checked whether the windshield wiper of the host vehicle operates to determine whether the current road is slippery (S 4 - 30 ). 
     When it is determined in S 4 - 30  that the current road is not slippery, an emergency braking control start time is maintained without a separate weight being applied when an emergency braking control start time is calculated (S 4 - 40 ). 
     When it is determined in S 4 - 10  on the basis of a result of recognizing the road sign that the current road is slippery, the emergency braking control start time is advanced by applying a weight (e.g., ranging from +30% to +70%) when calculating the emergency braking start time in consideration of the increase in braking distance (S 4 - 50 ). 
     Also, when it is determined in S 4 - 20  on the basis of the weather information that the current road is slippery, the emergency braking control start time is advanced by applying a weight (e.g., ranging from +30% to +70%) when calculating the emergency braking start time in consideration of the increase in braking distance (S 4 - 50 ). 
     Also, when it is determined in S 4 - 30  on the basis of the operation of the windshield wiper of the host vehicle that the current road is slippery, the emergency braking control start time is advanced by applying a weight (e.g., ranging from +30% to +70%) when calculating the emergency braking start time in consideration of the increase in braking distance (S 4 - 50 ). 
     Also, when a result of analyzing the road condition from the region-in-front image acquired using the camera system  1  is that the current road is slippery, the emergency braking control start time is advanced by applying a weight (e.g., ranging from +30% to +70%) when calculating the emergency braking start time in consideration of the increase in braking distance (S 4 - 50 ). 
     According to the present disclosure, it is possible to implement a voltage logic and a memory logic that may be used in a front-view camera system for an ADAS. 
     Also, according to the present disclosure, a scheme capable of coupling a lens barrel and a lens holder in a front-view camera system for an ADAS may be provided. 
     Also, according to the present disclosure, it is possible to control an emergency braking start time according to a degree to which a road is slippery. 
     Also, according to the present disclosure, it is possible to prevent a head-on/rear-end collision accident due to the increase in braking distance by advancing the emergency braking start time when it is determined that the road is slippery. 
     Sixth Embodiment 
     When a host vehicle is traveling at high speed, the possibility of an accident increases due to a vehicle cutting ahead of the host vehicle. In this case, when a driver&#39;s response is late, a collision with the vehicle ahead may occur. The collision may be prevented through vehicle deceleration, vehicle acceleration, and a change of a lane in which the vehicle is traveling. To this end, a technique for finding the presence of a vehicle traveling ahead of the host vehicle and a vehicle cutting ahead of the host vehicle is required. 
     The sixth embodiment of the present disclosure relates to a camera system for an ADAS and a driving assistance system for controlling a host vehicle using the camera system. 
     The sixth embodiment of the present disclosure will be described below with reference to  FIGS. 29A to 31 . 
       FIGS. 29A to 29C  are views illustrating lateral vehicle control according to the sixth embodiment of the present disclosure. 
     Reference will be made to  FIGS. 1, 3, and 29A to 29C . In  FIG. 29A , a host vehicle  5 - 100  may use the camera system  1  to discover the location of the host vehicle  5 - 100  and a region  5 - 110  ahead of the host vehicle  5 - 100  in a lane in which the host vehicle  5 - 100  is traveling. The region  5 - 110  ahead may refer to a lane ahead of the host vehicle  5 - 100  and a lane next to the front lane. The lane in which the host vehicle  5 - 100  is traveling is defined as the first lane  5 - 50 . The location of the host vehicle  5 - 100  in the first lane  5 - 50  may be a lateral distance between the host vehicle  5 - 100  and the first lane  5 - 50 . 
     In  FIG. 29B , the host vehicle  5 - 100  may use the camera system  1  to discover the first lane  5 - 50  in which the host vehicle  5 - 100  is traveling and a third-party vehicle  5 - 200  which cuts ahead of the host vehicle  5 - 100 . In this case, the camera system  1  may discover a distance between the host vehicle  5 - 100  and the first lane  5 - 50  by discovering the first lane  5 - 50 . In this case, the ECU  5 - 320  may calculate a location at which the host vehicle  5 - 100  is placed in the first lane  5 - 50 . In detail, the ECU  5 - 320  may calculate a first distance d 1  between the first lane  5 - 50  and the left side of the host vehicle  5 - 100  and a second distance d 2  between the first lane  5 - 50  and the right side of the host vehicle  5 - 100 . Also, the ECU  5 - 320  may obtain a lateral positional relationship between the host vehicle  5 - 100  and the third-party vehicle  5 - 200  through information regarding the first lane  5 - 50  detected by the camera system  1  and information regarding the location of the third-party vehicle  5 - 200 . As an example, the ECU  5 - 320  may obtain the lateral locations of the host vehicle  5 - 100  and the third-party vehicle  5 - 200  through the location of the third-party vehicle  5 - 200 , the first-lane overlapping degree between the host vehicle  100  and the third-party vehicle  5 - 200 , and the like, which are detected by the camera system  1 . 
     Also, a radar apparatus may measure the distance between the host vehicle  5 - 100  and the third-party vehicle  5 - 200 . A radar system is a sensor that uses electromagnetic waves to measure the distance, speed, or angle of an object. Generally, the radar system may be located at the front grille of a vehicle to cover even a front lower portion of the vehicle. The reason why the radar apparatus is disposed at the front grill, that is, outside the vehicle, in other words, the reason why the radar apparatus is not allowed to transmit and receive signals through the windshield of the vehicle is a reduction in sensitivity when electromagnetic waves pass through glass. According to the present disclosure, the electromagnetic waves may be prevented from passing through the windshield while the radar apparatus is located inside the vehicle, in particular, below the windshield inside the vehicle. To this end, the radar apparatus is configured to transmit and receive electromagnetic waves through an opening provided in an upper portion of the windshield. Also, a cover is disposed at a location corresponding to the opening for the radar apparatus. The cover is to prevent loss (e.g., an inflow of air, etc.) due to the opening. Also, it is preferable that the cover be made of a material capable of being easily penetrated by electromagnetic waves of frequencies the radar apparatus uses. As a result, the radar apparatus is located inside the vehicle, but electromagnetic waves are transmitted and received through the opening provided in the windshield. The cover corresponding to the opening is provided in order to prevent the loss due to the opening, and the electromagnetic waves are transmitted and received through the cover. The radar apparatus may use beam aiming, beam selection, digital beam forming, and digital beam steering. Also, the radar apparatus may include an array antenna or a phased array antenna. In this case, the ECU  5 - 320  may obtain a lateral positional relationship between the host vehicle  5 - 100  and the third-party vehicle  5 - 200  through the information measured by the radar apparatus. 
     In  FIG. 29C , the ECU  5 - 320  may determine a risk of collision with the third-party vehicle  5 - 200  on the basis of the location of the host vehicle  5 - 100  in the first lane  5 - 50  and thus may control the steering and speed of the host vehicle  5 - 100 . The camera system  1  may discover whether another vehicle is present in the second lane, which is opposite to a lane from which the third-party vehicle  5 - 200  cuts into the first lane  5 - 50 . 
     As an example, when there is no vehicle in the second lane, the ECU  5 - 320  may control the steering of the host vehicle  5 - 100  so that the host vehicle  5 - 100  makes a lane change to the second lane. By the control of the ECU  5 - 320 , it is possible to prevent a collision between the host vehicle  5 - 100  and the third-party vehicle  5 - 200 . 
       FIGS. 30A to 30C  are views illustrating longitudinal vehicle control according to the sixth embodiment of the present disclosure. For simplicity of description, a repetitive description of those described with reference to  FIGS. 29A to 29C  will be omitted.  FIGS. 30A and 30B  are the same as or similar to  FIGS. 29A and 29B , and thus a description thereof will be omitted. 
     Reference will be made to  FIGS. 1, 3, and 30A -C. In  FIG. 30C , the ECU  5 - 320  may determine a risk of collision with the third-party vehicle  5 - 200  on the basis of the location of the host vehicle  5 - 100  in the first lane  5 - 50  and thus may control the steering and speed of the host vehicle  5 - 100 . The camera system  1  may discover whether another vehicle is present in the second lane, which is opposite to a lane from which the third-party vehicle  5 - 200  cuts into the first lane  5 - 50 . 
     As an example, when a third vehicle  5 - 300 , which is still another vehicle, is present in the second lane, the ECU  5 - 320  may determine whether the host vehicle  5 - 100  can pass the third-party vehicle  5 - 200  before the third-party vehicle  5 - 200  completely enters the first lane  5 - 50 . In detail, the ECU  5 - 320  may determine whether the host vehicle  5 - 100  can pass the third-party vehicle  5 - 200  through the lateral and longitudinal positional relationships between the host vehicle  5 - 100  and the third-party vehicle  5 - 200 , which are discovered by the camera system  1 , and the speeds of the host vehicle  5 - 100  and the third-party vehicle  5 - 200 , which are discovered by the radar apparatus. When it is determined that the host vehicle  5 - 100  can pass the third-party vehicle  5 - 200 , the ECU  5 - 320  may accelerate the host vehicle  5 - 100 . On the other hand, when it is determined that the host vehicle  5 - 100  cannot pass the third-party vehicle  5 - 200 , the ECU  5 - 320  may decelerate the host vehicle  5 - 100  to prevent a collision with the third-party vehicle  5 - 200 . Thus, the third-party vehicle  5 - 200  may enter the first lane  5 - 50  and may be located ahead of the host vehicle  5 - 100 . 
       FIG. 31  is a flowchart illustrating vehicle control according to the sixth embodiment of the present disclosure. 
     Referring to  FIG. 31 , a camera system installed in a host vehicle may discover a region ahead of the host vehicle. The camera system may recognize a vehicle ahead and a lane which are located ahead of the host vehicle (S 5 - 10 ). When a third-party vehicle cuts ahead into a lane in which the host vehicle is traveling, the camera system may discover the lateral location of the third-party vehicle through the location of the third-party vehicle and the overlapping degree between the third-party vehicle and the lane (S 5 - 20 ). The ECU may determine the lateral and longitudinal positional relationships between the host vehicle and the third-party vehicle through information regarding the location of the host vehicle and the location of the third-party vehicle in the first lane, which is acquired by the camera system, and information regarding a distance between the host vehicle and the third-party vehicle, which is acquired by the radar apparatus (S 5 - 30 ). In this case, the camera system may discover whether still another vehicle (a third-party vehicle) is present in a lane next to the lane in which the host vehicle is traveling. The next lane refers to a lane opposite to a lane from which the third-party vehicle is entering the first lane (S 5 - 45 ). When a third vehicle is present in the next lane, the ECU may decelerate or accelerate the host vehicle to prevent a collision between the host vehicle and the third-party vehicle. That is, the ECU may perform longitudinal control on the host vehicle (S 5 - 51 ). When no third vehicle is present in the next lane, the ECU may control the steering of the host vehicle so that the host vehicle enters the next lane. That is, the ECU may perform lateral control on the host vehicle. In addition, the ECU may control the speed of the host vehicle (S 5 - 53 ). 
     Seventh Embodiment 
     At an intersection, a host vehicle may go straight, turn around, or turn left or right, and vehicles other than the host vehicle may also turn around or turn left or right. Thus, a vehicle collision accident may occur frequently. When a collision between the host vehicle and a nearby vehicle is expected, a CTA system according to the related art performs only braking control. Also, the convention CTA system does not have a function of warning a driver of a collision risk or of controlling steering to avoid the collision, and thus has a limitation in preventing a collision accident at an intersection. 
     The seventh embodiment of the present disclosure is directed to providing a camera system for an ADAS and a CTA system and method which are capable of performing steering control on the host vehicle as well as capable of sensing a risk of collision between the host vehicle and a nearby vehicle at an intersection on the basis of whether the host vehicle is stopped or traveling and whether the steering wheel is operated and capable of warning the driver of a collision risk according to a collision risk level. 
     The seventh embodiment will be described below with reference to  FIGS. 32A, 32B, 33A, and 33B . 
       FIG. 32A  is a diagram showing an example in which a warning for a collision risk is not issued when while a host vehicle is stopped at an intersection and the steering wheel is not operated according to the seventh embodiment of the present disclosure. 
     Referring to  FIG. 32A , when a host vehicle A is stopped at an intersection and the steering wheel is not operated, that is, the driver has no intention to turn left, right, or around, there is less or no risk of collision between the host vehicle A and a nearby vehicle B. Accordingly, a separate warning for the collision risk is not issued. 
       FIG. 32B  is a diagram showing an example in which a warning for a first-level collision risk is issued when a host vehicle is stopped at an intersection and the steering wheel is operated. 
     Referring to  FIG. 32B , when the host vehicle A is stopped at the intersection, an ECU  6 - 320  checks whether the steering wheel is operated to turn left, right, or around. Also, when the steering wheel of the host vehicle A is operated, the ECU  6 - 320  determines whether there is a risk of collision with the nearby vehicle B while the host vehicle A is traveling in a desired direction. 
     Here, at least one of a lidar MCU  6 - 311 , a radar MCU  6 - 312 , and a camera MCU  6 - 42  may detect the nearby vehicle B, and the ECU  6 - 320  may determine whether there is a risk of collision between the host vehicle A and the nearby vehicle B. When the steering wheel is operated while the host vehicle A is stopped, the ECU  6 - 320  determines a first-level risk of collision between the host vehicle A and the nearby vehicle B and warns the driver of the first-level collision risk. 
     When the warning for the first-level collision risk is issued, a driver warning controller  6 - 331  may display a video warning message or a warning image to the driver through an HUD or a side mirror display to warn the driver of the first-level collision risk. 
       FIG. 33A  is a diagram showing an example in which a warning for a second-level collision risk is issued when a host vehicle starts traveling at an intersection and is expected to collide with a nearby vehicle. 
     Referring to  FIG. 33A , when a host vehicle A starts traveling at the intersection and the steering wheel is operated to turn left, right, or around, the ECU  6 - 320  determines whether there is a risk of collision between the host vehicle A and a nearby vehicle B. 
     When a risk of collision between the host vehicle and the nearby vehicle is expected while the vehicle is traveling in a direction in which the steering wheel is operated, the ECU  6 - 320  determines a second-level collision risk and warns the driver of the second-level collision risk. When the host vehicle starts traveling although the warning for the first collision risk is issued while the host vehicle A is stopped, the risk of collision with the nearby vehicle increases, and thus the ECU  6 - 320  determines the second-level collision risk. 
     When the warning for the second-level collision risk is issued, the driver warning controller  6 - 331  displays a video warning message or a warning image to the driver through an HUD or a side mirror display and also generates a warning signal in an audio manner. In this case, the driver warning controller  6 - 331  may use a vehicle sound system to output warning sounds. That is, when the host vehicle starts traveling at an intersection and the steering wheel is operated to turn left, right, or around, the ECU  6 - 320  determines the second-level collision risk and outputs a video collision warning and an audio collision warning simultaneously to warn the driver of the second-level warning risk. 
       FIG. 33B  is a diagram showing an example in which a warning for a third-level collision risk is issued when a host vehicle starts traveling at an intersection and is expected to collide with a nearby vehicle and the steering wheel is not operated for the purpose of braking or collision avoidance. 
     Referring to  FIG. 33B , while the steering wheel is operated for the host vehicle to turn left, right, or around at an intersection, the ECU  6 - 320  determines whether there is a risk of collision with a nearby vehicle. Here, it is assumed that there is a collision risk when the host vehicle maintains a current traveling direction, but braking is not performed or the steering wheel is not operated to avoid the collision. In this case, the ECU  6 - 320  determines the third-level collision risk and warns the driver of the third-level collision risk. 
     When the warning for the first-level collision risk or the warning for the second-level collision risk is already issued or when the braking is not performed or the steering wheel is not operated for collision avoidance although the warning for the first-level collision risk or the warning for the second-level collision risk is issued, a serious collision risk is expected. In this case, the ECU  6 - 320  determines the third-level collision risk, and a steering controller  6 - 334  controls the steering of the host vehicle so that the host vehicle travels to avoid the collision, as well as the driver warning controller  6 - 331  issues the warning for the second-level collision risk. 
     When the warning for the third-level collision risk is issued, the driver warning controller  6 - 331  displays a video warning message or a warning image to the driver through an HUD or a side mirror display and also generates a warning signal in an audio manner. In this case, the driver warning controller  6 - 331  may use a vehicle sound system to output warning sounds. That is, when the host vehicle starts traveling at an intersection and the steering wheel is operated to turn left, right, or around, the ECU  6 - 320  determines the second-level collision risk and outputs a video collision warning and an audio collision warning simultaneously. Furthermore, the steering controller  6 - 334  controls the steering of the host vehicle to avoid a collision between the host vehicle and the nearby vehicle. 
     Here, the steering controller  6 - 334  controls an electronic power steering system (MPDS) for driving the steering wheel. When the vehicle is expected to collide, the steering controller  6 - 334  controls the steering of the vehicle such that the collision may be avoided or such that damage may be minimized. 
     When the warning for the third-level collision risk is issued, a suspension controller  6 - 336  controls the host vehicle such that the posture of the host vehicle is normally maintained, in response to a sudden steering operation for collision avoidance. That is, even when steering control is suddenly performed to avoid the collision, the vehicle posture is maintained to ensure ride comfort and driving stability. 
     When the warning for the third-level collision risk is issued, but the collision avoidance cannot be guaranteed only by the steering control, the ECU  6 - 320  may use a brake controller  6 - 337  to brake the vehicle. That is, when the warning for the third-level risk is issued, the brake controller  6 - 337  brakes the vehicle on the basis of the control of the ECU  6 - 320 . 
     Here, when a forward collision is probable, the brake controller  6 - 337  may perform control so that emergency braking is automatically activated according to a control command of the ECU  6 - 320  irrespective of whether the driver operates the brake. 
     With the CTA system and method according to the present disclosure, it is possible to sense a risk of collision between a host vehicle and a nearby vehicle at an intersection and warn a driver of the collision risk according to the level of the collision risk. Also, it is possible to avoid a collision by controlling the steering of the host vehicle as well as issuing the warning for the collision risk according to the level of the collision risk. 
     Eighth Embodiment 
     The eighth embodiment of the present disclosure relates to implementation of automatic emergency braking on the basis of a longitudinal TTC and a lateral TTC between a host vehicle and a third-party vehicle in a front-view camera system for an ADAS. 
     The eighth embodiment of the present disclosure will be described below with reference to  FIGS. 24 and 25 . 
       FIG. 34  is a diagram illustrating a host vehicle, a third-party vehicle, and a TTC according to the eighth embodiment of the present disclosure. 
       FIG. 34  shows a host vehicle  7 - 610  and a third-party vehicle  7 - 620 . The host vehicle  7 - 610  is a vehicle equipped with a camera system according to the present disclosure, and the third-party vehicle  7 - 620  is any vehicle other than the host vehicle  7 - 610 . As shown in  FIG. 34 , the third-party vehicle  7 - 620  is traveling laterally with respect to the host vehicle  7 - 610 . As a representative example, the lateral traveling may occur at an intersection. The TTC is the time required for the host vehicle  7 - 610  and the third-party vehicle  7 - 620  to collide with each other. The TTC may be considered as being divided into a longitudinal TTC (TTC x ) and a lateral TTC (TTC y ). That is, the lateral TTC (TTC y ) corresponds to the time required for the third-party vehicle  7 - 620  to collide with the host vehicle  7 - 610  along a traveling path of the host vehicle  7 - 610 , and the longitudinal TTC (TTC x ) corresponds to the time required for the host vehicle  7 - 610  to collide with the third-party vehicle  7 - 620  along a traveling path of the third-party vehicle  7 - 620 . 
       FIG. 35  is a diagram illustrating an autonomous emergency braking (AEB) control algorithm according to the eighth embodiment of the present disclosure. Such an AEB control algorithm may be performed by the camera system installed in the host vehicle. In detail, the AEB control algorithm may be performed by an image processor in the camera system. However, the present disclosure is not limited thereto, and it is to be understood that the AEB control algorithm may be performed by a camera MCU, another MCU, an ECU, or a combination of a plurality of MCUs and/or ECUs. 
     First, a third-party vehicle ahead is detected (S 7 - 710 ). The third-party vehicle is a vehicle traveling laterally with respect to the host vehicle. As a representative example, such a situation may occur at an intersection. 
     Subsequently, the longitudinal TTC (TTC x ) between the host vehicle and the third-party vehicle is calculated (S 7 - 720 ). The longitudinal TTC is the time required for the host vehicle to collide with respect to a traveling path of the third-party vehicle. The longitudinal TTC may be calculated by calculating an intersection point between the traveling path of the host vehicle and the traveling path of the third-party vehicle, calculating a distance between the host vehicle and the intersection point, and dividing the calculated distance by the speed of the host vehicle. 
     Subsequently, the lateral TTC (TTC y ) between the host vehicle and the third-party vehicle is calculated (S 7 - 730 ). The lateral TTC is the time required for the third-party vehicle to collide with respect to a traveling path of the host vehicle. The lateral TTC may be calculated by calculating an intersection point between the traveling path of the host vehicle and the traveling path of the third-party vehicle, calculating a distance between the third-party vehicle and the intersection point, and dividing the calculated distance by the speed of the third-party vehicle. 
     Subsequently, a difference between the longitudinal TTC and the lateral TTC is compared to a pre-determined threshold TTC th  (S 7 - 740 ). When it is determined that the absolute value of the difference is smaller than the pre-determined threshold, AEB is executed (S 7 - 750 ). When it is determined that the absolute value of the difference is larger than the pre-determined threshold, AEB is not executed. For example, when the longitudinal TTC is 10 seconds and the lateral TTC is 1 second, the absolute value of the difference is calculated as 9 seconds. Nine seconds are enough for the driver to depend (that is, the time is greater than a pre-determined threshold). In this case, the AEB is not executed. However, for example, when the longitudinal TTC is 10 seconds and the lateral TTC is 9 seconds, the absolute value of the difference is calculated as 1 second. One second is not enough for the driver to respond (that is, the time is smaller than the pre-determined threshold). In this case, the AEB is executed. 
     The pre-determined threshold is determined on the basis of at least one of a longitudinal TTC, a lateral TTC, a road condition, a road inclination, and a temperature. For example, when the longitudinal TTC and the lateral TTC are large (e.g., which are equal to 50 seconds and 49 seconds, respectively) although the absolute value of the difference is 1 second, it is preferable that the pre-determined threshold be set to be small. On the other hand, when the longitudinal TTC and the lateral TTC are small (e.g., which are equal to 5 seconds and 4 seconds, respectively) although the absolute value of the difference is 1 second, it is preferable that the pre-determined threshold be set to be large. Also, it is preferable that the pre-determined threshold be set to be larger when the road is wet than when the road is dry. Also, it is preferable that the pre-determined threshold be set to be larger when the road is downhill than when the road is uphill or flat. Also, it is preferable that the threshold value be set to be larger when the temperature is low than when the temperature is high. 
     Ninth Embodiment 
     A vehicle entering an intersection is more likely to collide with a nearby vehicle. When the host vehicle is decelerated or stopped while entering the intersection, a vehicle traveling behind the host vehicle may not recognize a signal at the intersection and thus may not decelerate. Accordingly, the collision risk may increase. In order to prepare for such a case, recently, research has been actively conducted on a control or warning system capable of a driver avoiding a collision possibility. 
     The ninth embodiment of the present disclosure relates to a camera system for an ADAS and a driving assistance system for warning a driver using the camera system. 
     The ninth embodiment will be described below with reference to  FIGS. 36 and 37 . 
       FIG. 36  is a diagram showing an example in which a host vehicle recognizes an ambient situation at an intersection according to an ninth embodiment of the present disclosure. For simplicity of description, a repetitive description will be omitted. 
     Referring to  FIGS. 3 and 36 , there are a host vehicle  8 - 1000  entering an intersection and a nearby vehicle  8 - 1200  traveling behind or beside the host vehicle  8 - 1000 . The host vehicle  8 - 1000  may be equipped with a camera system  1  for sensing a region ahead with respect to a vehicle traveling direction and a rear radar  8 - 1030  for recognizing regions behind and to a side. Generally, the camera system  1  may be placed on the front of the host vehicle  8 - 1000 , and the rear radar  8 - 1030  may be placed on the rear of the host vehicle  8 - 1000 . However, the rear radar  8 - 1030  may be placed on the side of the host vehicle  8 - 1000 , and the locations of the camera system  1  and the rear radar  8 - 1030  may not be particularly limited. 
     The camera system  1  may sense that the signal of a traffic light  8 - 1100  changes from green to yellow or red. That is, the camera system  1  may sense that the signal of the traffic light  8 - 1100  changes from a “Go” signal to a “Stop” signal and may transmit data regarding the sensed signal to an ECU  8 - 320 . The driver is aware of the yellow or red signal of the traffic light  8 - 1100  and decelerates the host vehicle  8 - 1000 . 
     The rear radar  8 - 1030  may recognize the nearby vehicle  8 - 1200  that may be likely to collide with the host vehicle  8 - 1000 . The rear radar  8 - 1030  may be the radar apparatus that has been described with reference to  FIG. 3 . The rear radar  8 - 1030  may measure the presence of the nearby vehicle  8 - 1200 , the distance from the nearby vehicle  8 - 1200 , the speed of the nearby vehicle  8 - 1200 , the traveling angle of the nearby vehicle  8 - 1200 , etc. The traveling angle may refer to a direction in which the nearby vehicle  8 - 1200  is actually traveling with respect to the direction of a lane in which the nearby vehicle  8 - 1200  is traveling. The rear radar apparatus  8 - 1030  may be used to sense objects ahead within a horizontal angle of 30 degrees and a distance of 150 meters by FMCW or Pulse Carrier. 
     The ECU  8 - 320  may receive signal data of the traffic light  8 - 1100  sensed by the camera system  1  and data regarding the nearby vehicle  8 - 1200  sensed by the rear radar  8 - 1030  and determine a risk of collision with the host vehicle  8 - 1000  and the nearby vehicle  8 - 1200 . As an example, when the host vehicle  8 - 1000  decelerates or travels at constant speed and the nearby vehicle  8 - 1200  located behind the host vehicle  8 - 1000  accelerates toward the host vehicle  8 - 1000 , the ECU  8 - 320  may determine a collision risk through data regarding a distance between the host vehicle  8 - 1000  and the nearby vehicle  8 - 1200 , which is measured by the rear radar  8 - 1030 . According to another example, when the host vehicle  8 - 1000  decelerates or travels at constant speed and the nearby vehicle  8 - 1200  located beside the host vehicle  8 - 1000  is steered toward the host vehicle  8 - 1200 , the ECU  8 - 320  may determine a collision risk through data regarding a distance between the host vehicle  8 - 1000  and the nearby vehicle  8 - 1200 , which is measured by the rear radar  8 - 1030 , and data regarding a traveling angle of the nearby vehicle  8 - 1200 . As another example, when the host vehicle  8 - 1000  decelerates and the nearby vehicle  8 - 1200  accelerates toward the host vehicle  8 - 1000 , the ECU  8 - 320  may determine a collision risk through the degree of deceleration of the host vehicle  8 - 1000 , the degree of acceleration of the nearby vehicle  8 - 1200 , and the distance between the host vehicle  8 - 1000  and the nearby vehicle  8 - 1200 . The method in which the ECU  8 - 320  determines the collision risk is not limited thereto, and the collision risk may be variously determined by combining the data provided by the camera system  1  and the data provided by the rear radar  8 - 1030 . 
     When it is determined that there is a possibility of a collision between the host vehicle  8 - 1000  and the nearby vehicle  8 - 1200 , the ECU  8 - 320  may control a driver warning controller  8 - 331  to warn the driver of the collision risk. The driver warning controller  8 - 331  may warn the driver by using at least one of video, audio, and steering wheel vibration. For example, when there is a possibility of a collision between the host vehicle  8 - 1000  and the nearby vehicle  8 - 1200 , the ECU  8 - 320  may warn the driver through a dashboard or an HUD in a video manner, warn the driver by generating warning sounds, or warn the driver by vibrating the steering wheel above a certain intensity level. The certain intensity level may be defined as an intensity level greater than normal vibration of the steering wheel that the driver may feel while driving. 
       FIG. 37  is a flowchart illustrating an example in which a driver is warned depending on an ambient situation of a host vehicle according to the ninth embodiment of the present disclosure. The following description with reference to  FIG. 37  will focus on an example in which a vehicle behind is recognized. 
     Referring to  FIG. 37 , a traffic light located ahead of the host vehicle may be recognized through a camera system installed in the host vehicle. Through the camera system, a change of the signal of the traffic light from green (indicating a “Go” signal) to yellow or red (indicating a “Stop” signal) may be recognized (S 8 - 10 ). When the signal of the traffic light is changed to yellow or red, a vehicle behind may be recognized through a rear radar. In this case, the rear radar may be discover the presence of a vehicle behind, the speed of a vehicle behind, a distance between the host vehicle and a vehicle behind, and the traveling angle of a vehicle behind (S 8 - 20 ). The ECU may determine a possibility of collision between the host vehicle and the vehicle behind by combining the data discovered by the camera system and the data discovered by the rear radar. When the collision possibility is determined, the ECU may mainly compare the speed of the host vehicle and the speed of the vehicle behind. In addition, the ECU may compare the speed of the host vehicle and the data regarding the vehicle behind, which is detected by the rear radar, to determine a collision possibility (S 8 - 35 ). When there is no collision possibility, the host vehicle may stop or go according to the control of the driver. When the host vehicle enters an intersection again, the ECU may recognize a traffic light at the intersection. When there is a collision possibility, the ECU may warn the driver that there is a collision possibility. When the driver is warned, the driver may control the host vehicle to help avoiding the collision with the vehicle behind (S 8 - 40 ). 
     Tenth Embodiment 
     An intersection is a point where traveling paths of vehicles intersect each other, and thus an accident may occur frequently at an intersection. In particular, when the signal of a traffic light at an intersection is changed, vehicles may cross the intersection without recognizing a “Stop signal” of the traffic light. In this case, there is a need for a technique for determining a collision possibility through the speeds of vehicles and a distance between vehicles irrespective of the presence or absence of the signal. 
     The tenth embodiment of the present disclosure relates to a driving assistance system for avoiding a collision between vehicles. 
     The tenth embodiment will be described below with reference to  FIGS. 38 to 40 . 
       FIG. 38  is a diagram showing locations of a host vehicle and a nearby vehicle at an intersection according to the tenth embodiment of the present disclosure. For simplicity of description, a repetitive description will be omitted. 
     Referring to  FIGS. 3 and 38 , a host vehicle  9 - 1000  and a nearby vehicle  9 - 1200  enter an intersection. As an example, the host vehicle  9 - 1000  may change steering to turn left, and thus the traveling directions of the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  may intersect each other. The host vehicle  9 - 1000  may be equipped with a sensor  9 - 1100  and a camera system  1  for sensing a region ahead of the host vehicle  9 - 1000 . The camera system  1  may acquire an image of the region ahead of the host vehicle  9 - 1000  and measure the presence and location of the nearby vehicle  9 - 1200 . The sensor  9 - 1100  may measure a distance between the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  and the speed (relative speed or absolute speed) of the nearby vehicle  9 - 1200 . The sensor  9 - 1100  may include at least one of a radar and a Lidar. 
     An ECU  9 - 320  may determine a risk of collision between the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  through the data acquired by the camera system  1  and the data acquired by the sensor  9 - 1100  and may calculate a TTC, which is a time to collision. The TTC may be calculated through the traveling paths of the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200 , the speed (relative speed or absolute speed) of the nearby vehicle  9 - 1200 , and the location of the nearby vehicle  1200  acquired through the camera system  1 . 
     The ECU  9 - 320  may set a vehicle control start time after calculating the TTC. The vehicle control start time may refer to a time at which a possibility of collision between the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  is recalculated after the TTC is calculated. The vehicle control start time may include a first vehicle control start time and a second vehicle control start time, and the first vehicle control start time may precede the second vehicle control start time. That is, after the collision possibility is re-determined at the first vehicle control start time, the collision possibility is determined at the second vehicle control start time. The ECU  9 - 320  may recalculate the possibility of collision between the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  gain in the first and second vehicle control start time and may control the host vehicle  9 - 1000 . The ECU  9 - 320  may control a warning controller  9 - 331 , a steering controller  9 - 334 , and a brake controller  9 - 337  in order to control the host vehicle  9 - 1000 . However, controller controlled by the ECU  9 - 320  are not limited thereto. 
     As an example, when the camera system  1  recognizes the nearby vehicle  9 - 1200  ahead of the host vehicle  9 - 1000 , the ECU  9 - 320  may calculate a first TTC and may calculate a second TTC at the first vehicle control start time. In this case, when the second TTC is smaller than the first TTC, the ECU  9 - 320  may generate a warning to warn the driver. For example, the warning may include a video warning, an audio warning, and a steering handle vibration warning. The ECU  9 - 320  may calculate a third TTC at the second vehicle control start time. In this case, when the third TTC is smaller than the first TTC or the second TTC, the ECU  9 - 320  may control the steering and brake of the host vehicle  9 - 1000  to avoid the collision. 
       FIG. 39  is a diagram showing 2D coordinates of a nearby vehicle with respect to a host vehicle according to the tenth embodiment of the present disclosure. 
     Referring to  FIGS. 3, 6, and 39 , a traveling route  9 - 1010  of the host vehicle  9 - 1000  may intersect a traveling route  9 - 1210  of the nearby vehicle  9 - 120 , and thus there is a collision possibility therebetween. The sensor  9 - 1100  may measure a straight distance DO between the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  and may measure the speed (relative speed or absolute speed) of the nearby vehicle  9 - 1200 . 
     As an example, the ECU  9 - 320  may calculate a TTC of the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  using a relative distance between the host vehicle  9 - 1000  and the nearby vehicle  9 - 1200  and the relative speed of the nearby vehicle  9 - 1200 . That is, the ECU  9 - 320  may obtain the TTC by dividing the relative distance with respect to the nearby vehicle  9 - 1200  by the relative speed with respect to the nearby vehicle  9 - 1200 . 
     As another example, the ECU  9 - 320  may generate 2D coordinates of the nearby vehicle  9 - 1200  with respect to the host vehicle  9 - 1000  through the camera system  1  and the sensor  9 - 1100 . The ECU  9 - 320  may calculate an expected collision point P by comparing a travelable distance Dp corresponding to the absolute speed of the nearby vehicle  9 - 1200  and a traveling distance Dx corresponding to the absolute speed of the host vehicle  9 - 1200  through the 2D coordinates and may find a TTC on the basis of the expected collision point P. 
       FIG. 40  is a flowchart illustrating the order of controlling a host vehicle according to the tenth embodiment of the present disclosure. 
     Referring to  FIG. 40 , a camera system installed in the host vehicle may recognize a nearby vehicle traveling ahead of the host vehicle (S 9 - 10 ). When the nearby vehicle ahead of the host vehicle is recognized, the sensor may measure the speed of the vehicle ahead and a distance between the host vehicle and the nearby vehicle. The ECU may generate 2D coordinates of the nearby vehicle with respect to the host vehicle through the data measured by the camera system and the data measured by the sensor. The 2D coordinates may be generated in consideration of the locations of the host vehicle and the nearby vehicle and the traveling routes of the host vehicle and the nearby vehicle (S 9 - 20 ). The ECU  9 - 320  may calculate a first TTC of the host vehicle and the nearby vehicle by combing information regarding the speeds of the host vehicle and the nearby vehicle with information regarding the 2D coordinates. Subsequently, the ECU  9 - 320  may re-determine a possibility of collision between the host vehicle and the nearby vehicle and may calculate a second TTC. In this case, when the second TTC is smaller than the first TTC, that is, when the time to collision decreases, the ECU may generate a warning and inform the driver that there is a collision possibility. When the second TTC is large than the first TTC, that is, when the time to collision increases, the ECU may determine that there is no collision possibility such that separate control may not be performed. For example, when the driver changes steering so that the traveling route is changed in the opposite direction before the second TTC is calculated, the collision possibility may decrease (S 9 - 35 , S 9 - 40 ). When the driver is warned, the ECU may re-determine a possibility of collision between the host vehicle and the nearby vehicle and may calculate a third TTC. In this case, when the third TTC is smaller than the first TTC and the second TTC, that is, when the time to collision decreases, the ECU may control the steering of the host vehicle or drive the brake to avoid a collision between the host vehicle and the nearby vehicle (S 9 - 55 , S 9 - 60 ). 
     Eleventh Embodiment 
     At an intersection, a host vehicle may go straight, turn around, or turn left or right, and nearby vehicles (vehicles traveling laterally) other than the host vehicle may also turn around or turn left or right. Thus, a vehicle collision accident may occur frequently. In particular, a collision accident may occur due to a laterally appearing pedestrian and nearby vehicle. However, when a collision between the host vehicle and a nearby vehicle is expected, a CTA system according to the related art performs only braking control on the host vehicle. When the CTA system is applied to a plurality of vehicles entering an intersection, all of the vehicles may be braked to rather cause a bigger accident. 
     The eleventh embodiment of the present disclosure relates to a CTA system and method capable of setting a priority for CTA control between a host vehicle and a nearby vehicle so that the host vehicle may avoid a collision with a laterally appearing pedestrian and vehicle when the host vehicle enters an intersection. 
     The eleventh embodiment of the present disclosure will be described below with reference to  FIGS. 41 to 44 . 
       FIG. 41  is a diagram showing a CTA system according to the eleventh embodiment of the present disclosure, and  FIG. 42  is a diagram showing controllers controlled for collision avoidance and a control unit shown in  FIG. 41 . 
     Referring to  FIGS. 41 and 42 , the CTA system according to the eleventh embodiment of the present disclosure includes a camera system, a radar system, and a control unit  10 - 170 . 
     The camera system includes at least one camera  10 - 110 . The camera  10 - 110  may include a mono camera, a stereo camera, or a surround vision camera and may capture regions ahead of, behind, to the left of, and to the right of the vehicle to generate image data. The image data generated by the camera  10 - 110  is provided to the control unit  10 - 170 . 
     The radar system includes a front radar  10 - 120 , a front right radar  10 - 130 , a front left radar  10 - 140 , a rear right radar  10 - 150 , a rear left radar  10 - 160 , and a plurality of radar MCUs for driving the radars. 
     The radar system emits radio waves to the regions ahead of, behind, to the left of, and to the right of the host vehicle and then receives reflected waves to detect objects located ahead, behind, to the left, and to the right within a distance of 150 meters and a horizontal angle of 30 degrees. Here, the radar system detects the objects using FMCW and Pulse Carrier and transmits radar data including a result of detecting the objects to the control unit  10 - 170 . 
     The control unit  10 - 170  includes a receiving unit  10 - 172 , an ECU  10 - 320 , and a transmitting unit  10 - 174 . 
     The receiving unit  10 - 172 , which is disposed in the host vehicle, is connected to a transmitting unit of a nearby vehicle in a wireless communication manner (e.g., 4G long term evolution (LTE)) and is configured to receive a nearby vehicle-specific CTA control signal from the nearby vehicle. The received nearby vehicle-specific CTA control signal is transmitted to the ECU  10 - 320 . 
     The transmitting unit  10 - 174 , which is disposed in the host vehicle, is connected to a receiving unit of a nearby vehicle in a wireless communication manner (e.g., 4G LTE) and is configured to transmit a host vehicle-specific CTA control signal generated by the ECU  10 - 320  to the nearby vehicle. 
     Intersection CTA Control of Host Vehicle 
       FIG. 43  is a diagram showing an example in which nearby vehicles are detected by a camera system and a radar system disposed in a host vehicle, and  FIG. 44  is a diagram showing a method of setting control priorities of a CTA system when a plurality of vehicles enter an intersection. 
     Referring to  FIGS. 43 and 44 , the ECU  10 - 320  detects nearby vehicles B 1  to B 5  on the basis of image data and radar data when a host vehicle A enters an intersection. Also, the ECU  10 - 320  determines collision possibilities between the host vehicle A and the nearby vehicles B 1  to B 5  and generates a host vehicle-specific CTA control signal when there is a collision possibility. The ECU  10 - 320  generates a vehicle control signal for controlling the host vehicle according to the CTA control signal and supplies the generated vehicle control signal to a vehicle posture controller  10 - 333 , a steering controller  10 - 334 , an engine controller  10 - 335 , a suspension controller  10 - 336 , and a brake controller  10 - 337 . In this way, the host vehicle may be controlled to travel at an intersection without CTA emergency braking, steering avoidance, deceleration, acceleration, or CTA control. 
     CTA Control Priority Determination and CTA Control Between Host Vehicle and Nearby Vehicle 
     The ECU  10 - 320  detects nearby vehicles B 1  and B 2  on the basis of image data and radar data when the host vehicle A enters an intersection. Also, the ECU  10 - 320  determines collision possibilities between the host vehicle A and the nearby vehicles B 1  and B 2  and generates a host vehicle-specific CTA control signal when there is a collision possibility. The host vehicle-specific CTA control signal generated by the ECU  10 - 320  is transmitted to the nearby vehicles B 1  and B 2  through the transmitting unit  10 - 174 . 
     Here, by comparing CTA control signals transmitted and received between the host vehicle and the nearby vehicles, The ECU  10 - 320  determines a vehicle for performing CTA emergency braking, a vehicle for performing steering avoidance, a vehicle for performing deceleration, a vehicle for performing acceleration, and a vehicle for traveling without CTA control. That is, by determining CTA control priorities of a plurality of vehicles and sharing the determined CTA control priorities between the host vehicle and the nearby vehicles, the CTA control may be systematically performed at an intersection. In this case, by comparing a CTA control signal of any one of the nearby vehicles as well as the host vehicle and CTA control signals of other nearby vehicles, the ECU  10 - 320  may determine a vehicle for performing CTA emergency braking, a vehicle for performing steering avoidance, a vehicle for performing deceleration, a vehicle for performing acceleration, and a vehicle for traveling without CTA control. 
     The ECU  10 - 320  generates a vehicle control signal for controlling the host vehicle according to the CTA control priorities on the basis of the CTA control signal of the host vehicle or the CTA control signals of the nearby vehicles. 
     Also, the ECU  10 - 320  supplies the generated control signal to the vehicle posture controller  10 - 333 , the steering controller  10 - 334 , the engine controller  10 - 335 , the suspension controller  10 - 336 , and the brake controller  10 - 337 . In this way, the host vehicle may be controlled to travel at an intersection without CTA emergency braking, steering avoidance, deceleration, acceleration, or CTA control. 
     The CTA system and method according to the eleventh embodiment of the present disclosure may determine priorities for CTA control through communication between a host vehicle and nearby vehicles when the host vehicle enters an intersection and may enable a plurality of vehicles to systematically perform CTA control at the intersection according to the determined CTA priorities. Also, by detecting a laterally appearing vehicle or pedestrian and performing CTA control when the host vehicle enters the intersection, it is possible to prevent a collision. 
     Here, by controlling the steering controller  10 - 334 , the engine controller  10 - 335 , and the brake controller  10 - 337 , it is possible to avoid a collision at the intersection. In order to prevent a reduction of ride quality due to a significant change in speed or steering of the host vehicle and prevent an accident due to a drivers posture instability, the vehicle posture controller  10 - 333  and the suspension controller  10 - 336  are also controlled to ensure driving stability along with collision avoidance. 
     Twelfth Embodiment 
     Recently, research has been accelerated on systems for sensing the surroundings of a vehicle for the purpose of a driver&#39;s safety and convenience. The vehicle sensing system is used variously, for example, to sense empty space to perform autonomous parking as well as to sense objects near the vehicle to prevent a collision with an object that is not recognized by the driver. Also, the vehicle detection system provides the most essential data for automatic vehicle control. Typically, such a sensing system includes a system utilizing radar signals and a system utilizing cameras. The system utilizing radar signals is an apparatus for transmitting radar signals to a pre-determined sensing region, collecting signals reflected from the sensing region, analyzing the reflected signals, and sensing the surroundings of a vehicle. Advantageously, this system is excellent in terms of detection accuracy for the location and speed of the vehicle, is less influenced by external environments, and also is excellent in terms of detection performance for an object located longitudinally. However, the system is less accurate in detecting the location and speed of an object located laterally and in classifying objects and detecting information. The system utilizing cameras is an apparatus for analyzing image information acquired through camera capture and sensing the surroundings of the vehicle. Advantageously, this system is good in terms of object classification and detection accuracy for object information. Also, this system is good in terms of speed detection for an object located laterally. However, the system configured to use cameras is easily affected by external environments and has relatively low detection accuracy for distance and speed compared to the system configured to use radar signals. 
     The twelfth embodiment of the present disclosure relates to a system for sensing a vehicle and pedestrian traveling laterally at an intersection through a combination of a camera and a radar. 
     The twelfth embodiment of the present disclosure will be described below with reference to  FIGS. 45 to 49 . 
       FIG. 45  is a diagram showing a configuration of a vehicular control device according to the twelfth embodiment of the present disclosure. 
     Referring to  FIG. 45 , a vehicular control device  11 - 100  according to the twelfth embodiment of the present disclosure includes a image generation unit  11 - 110 , a first information generation unit  11 - 120 , a second information generation unit  11 - 130 , and a control unit  11 - 140 . 
     The image generation unit  11 - 110  may include at least one camera disposed in a host vehicle  11 - 10  and may capture a region ahead of the host vehicle  11 - 10  to generate an image regarding the region ahead of the host vehicle  11 - 10 . Also, the image generation unit  11 - 110  may capture a region surrounding the host vehicle  11 - 10  in one or more directions, as well as the region ahead of the host vehicle  11 - 10 , to generate an image regarding the region surrounding the host vehicle  11 - 10 . 
     Here, the image regarding the region ahead and the image regarding the surrounding region may be digital images and may include color images, monochrome images, infrared images, etc. Also, the image regarding the region ahead and the image regarding the surrounding region may include still images and videos. The image generation unit  11 - 110  provides the image regarding the region ahead and the image regarding the surrounding region to the control unit  11 - 140 . 
     Subsequently, the first information generation unit  11 - 120  may include at least one radar disposed in the host vehicle  11 - 10  and may sense a region ahead of the host vehicle  11 - 10  and generate first sensing information. 
     In detail, the first information generation unit  11 - 120  is disposed in the host vehicle  11 - 10  and is configured to sense the locations and speeds of vehicles located ahead of the host vehicle  11 - 10 , the presence or location of a pedestrian, etc. and generate first sensing information. 
     By using the first sensing information generated by the first information generation unit  11 - 120 , it is possible to perform control to maintain a distance between the host vehicle  11 - 10  and a preceding vehicle, and it is also possible to increase vehicle operating stability when a driver wants to change a traveling lane of the host vehicle  11 - 10  or upon a pre-determined specific case, e.g., backward parking. The first information generation unit  11 - 120  provides the first sensing information to the control unit  11 - 140 . 
     Here, an intersection may be sensed using the image regarding the region ahead, which is generated by the image generation unit  11 - 110 , and the first sensing information, which is generated by the first information generation unit  11 - 120 . 
     Subsequently, when the intersection is sensed on the basis of the image regarding the region ahead, which is generated by the image generation unit  11 - 110 , and the first sensing information, which is generated by the first information generation unit  11 - 120 , the second information generation unit  11 - 130  senses the side of the host vehicle  11 - 10  and generates second sensing information. 
     In detail, the second information generation unit  11 - 130  may include at least one radar disposed in the host vehicle  11 - 10 , and senses the locations and speeds of vehicles located to the side of the host vehicle  11 - 10 . Here, the second information generation unit  11 - 130  may include second information generation units disposed at both sides of the front and the rear of the host vehicle  11 - 10 . 
     In this case, when the intersection is sensed on the basis of the image regarding the region ahead, which is generated by the image generation unit  11 - 110 , and the first sensing information, which is generated by the first information generation unit  11 - 120 , the second information generation unit  11 - 130  increases the sensing of locations and speeds of vehicles located to the side of the host vehicle  11 - 10 . 
     In order to intensively sense vehicles located to the side of the host vehicle  11 - 10 , as an example, the second information generation unit  11 - 130  may increase the area of a sensing region to a side of the host vehicle  11 - 10 . Also, the second information generation unit  11 - 130  may increase the length of the sensing region to the side of the host vehicle  11 - 10  and may increase the number of times a vehicle is sensed in the sensing region to the side of the host vehicle  11 - 10  for a certain period of time by reducing the sensing cycle. The second information generation unit  11 - 130  provides the second sensing information to the control unit  11 - 140 . 
       FIG. 46  is a diagram showing sensing regions of the first information generation unit and the second information generation unit before an intersection is sensed. 
     Referring to  FIG. 46 , the first information generation unit  11 - 120  may include one or more radars, and may sense the locations and speeds of vehicles located ahead of the host vehicle  11 - 10  and generate the first sensing information. 
     Before the intersection is sensed, the first information generation unit  11 - 120  may increase the area of a sensing region ahead of the host vehicle  11 - 10  in order to intensively (mainly) sense the region ahead of the host vehicle  11 - 10 . Also, the first information generation unit  11 - 120  may increase the length of the sensing region ahead of the host vehicle  11 - 10  and may increase the number of times a vehicle is sensed in the sensing region ahead of the host vehicle  11 - 10  for the same period of time. 
     Also, the second information generation unit  11 - 130  may include one or more radars and may sense the locations and speeds of vehicles located to the side of the host vehicle  11 - 10 . 
       FIG. 47  is a diagram showing a change in area of the sensing region of the second information generation unit after the intersection is sensed. 
     Referring to  FIG. 47 , when an intersection is sensed on the basis of the first sensing information and the image regarding the region ahead, the second information generation unit  11 - 130  may increase the area of the sensing region to the side of the host vehicle  11 - 10  to sense the locations and speeds of vehicles located to the side of the host vehicle  11 - 10  more intensively than the locations and speeds of vehicles located ahead of the host vehicle  11 - 10 . That is, the locations and speeds of vehicles located to the side of the host vehicle  11 - 10  rather than the locations and speeds of vehicles located ahead of the host vehicle  11 - 10  may be selected as critical sensing targets. 
       FIG. 48  is a diagram showing a change in length of the sensing region of the second information generation unit after an intersection is sensed. 
     Referring to  FIG. 48 , when an intersection is monitored on the basis of the first sensing information and the image regarding the region ahead, the second information generation unit  11 - 130  may increase the length of the sensing region to the side of the host vehicle  11 - 10  to select the locations and speeds of vehicles located to the side of the host vehicle  11 - 10  and also the locations and speeds of vehicles located ahead of the host vehicle  11 - 10  as critical sensing targets. 
     Subsequently, the control unit  11 - 140  selects a target vehicle  11 - 20  on the basis of the second sensing information, determines whether the host vehicle  11 - 10  will collide with the target vehicle  11 - 20 , and controls the host vehicle  11 - 10 . 
     In detail, the control unit  11 - 140  selects a vehicle close to the host vehicle  11 - 10  as the target vehicle  11 - 20  on the basis of the second sensing information. Also, the control unit  11 - 140  selects a vehicle that is not close to the host vehicle  11 - 10  but approaches the host vehicle  11 - 10  as the target vehicle  11 - 20 . In this case, the control unit  11 - 140  may determine that a stopped vehicle is a vehicle without a risk of collision and exclude the stopped vehicle from the selection of the target vehicle  11 - 20 . 
     The control unit  11 - 140  determines whether the host vehicle  11 - 10  will collide with the selected target vehicle  11 - 20 . Also, when it is determined that the host vehicle  11 - 10  will collide with the selected target vehicle  11 - 20 , the control unit  11 - 140  may warn the driver of the collision and may control the host vehicle  11 - 10  to be braked. 
       FIG. 49  is an operational flowchart illustrating a vehicle control method according to the twelfth embodiment of the present disclosure. 
     Referring to  FIG. 49 , the image generation unit  11 - 110  generates an image regarding a region ahead, and the first information generation unit  11 - 120  generates first sensing information (S 11 - 510 ). 
     In detail, the image generation unit  11 - 110  captures a region ahead of the host vehicle  11 - 10  to generate an image regarding the region ahead. Here, the image generation unit  11 - 110  may capture a region surrounding the host vehicle  11 - 10  in one or more directions, as well as the region ahead of the host vehicle  11 - 10 , to generate an image regarding the region surrounding the host vehicle  11 - 10 . 
     The first information generation unit  11 - 120  senses the region ahead of the host vehicle  11 - 10  and generates first sensing information. 
     Subsequently, when an intersection is sensed on the basis of the image regarding the region ahead and the first sensing information, the second information generation unit  11 - 130  generates second sensing information (S 11 - 520 ). 
     In detail, the second information generation unit  11 - 130  is disposed in the host vehicle  11 - 10  and is configured to sense the locations and speeds of vehicles located to the side of the host vehicle  11 - 10 . In this case, when the intersection is sensed, the second information generation unit  11 - 130  increases the sensing of the side of the host vehicle  11 - 10  and selects the side of the host vehicle  11 - 10  as a critical sensing region. Also, the second information generation unit  11 - 130  selects the locations and speeds of vehicles located to the side of the host vehicle  11 - 10  as critical sensing targets, and intensively senses the locations and speeds. 
     As an example, the second information generation unit  11 - 130  may increase the area of the sensing region to the side of the host vehicle  11 - 10  or the length of the sensing region to the side to increase the sensing of the side of the host vehicle  11 - 1 . Thus, the second information generation unit  11 - 130  may intensively sense the side of the host vehicle  11 - 10 . Also, the second information generation unit  11 - 130  may increase the number of times the sensing region to the side of the host vehicle  11 - 10  is sensed for a certain period of time by reducing the sensing cycle and thus may intensively sense the side of the host vehicle  11 - 10 . 
     Subsequently, the control unit  11 - 140  selects the target vehicle  11 - 20  on the basis of the second sensing information (S 11 - 530 ). 
     In detail, the control unit  11 - 140  selects a vehicle close to the host vehicle  11 - 10  as the target vehicle  11 - 20  on the basis of the second sensing information. Also, the control unit  11 - 140  may select, as the target vehicle, a vehicle approaching the host vehicle  11 - 10  from among traveling vehicles. 
     The control unit  11 - 140  may exclude a stopped vehicle, which is a vehicle with no risk of collision with the host vehicle  11 - 10 , from the selection of the target vehicle  11 - 20 . 
     Subsequently, the control unit  11 - 140  determines whether the host vehicle  11 - 10  will collide with the target vehicle  11 - 20  (S 11 - 540 ). 
     When it is determined that the host vehicle  11 - 10  will collide with the target vehicle  11 - 20 , the control unit  11 - 140  controls the host vehicle  11 - 10  (S 11 - 550 ). 
     In detail, when it is determined that the host vehicle  11 - 10  will collide with the target vehicle  11 - 20 , the control unit  11 - 140  may warn the driver of the collision and may control the braking apparatus to brake the host vehicle  11 - 10 . Thus, the control unit  11 - 140  may perform emergency braking on the host vehicle  11 - 10 . 
     When it is determined that the host vehicle  11 - 10  will not collide with the target vehicle  11 - 20 , the control unit  11 - 140  controls the host vehicle  11 - 10  to travel according to the driver&#39;s command (S 11 - 560 ). 
     As described above, according to the present disclosure, it is possible to implement a vehicle control apparatus and method capable of sensing an intersection using a camera and a radar disposed in the host vehicle  11 - 10  and capable of performing emergency braking on the host vehicle  11 - 10  and also issuing a warning to the driver when a collision between the host vehicle  11 - 10  and the target vehicle  11 - 20  is expected to occur at the sensed intersection. 
     Thirteenth Embodiment 
     An intersection is a point where traveling paths of vehicles intersect each other, and thus an accident may occur frequently at an intersection. In particular, when the signal of a traffic light at an intersection is changed, there is a high likelihood of a collision occurring in a direction that a driver is not watching. To this end, research is required on a technique capable of complementing a limited watching range of the driver. 
     The thirteenth embodiment of the present disclosure relates to an ADAS, and particularly, to a driving assistance system for avoiding a collision between vehicles. 
     The thirteenth embodiment will be described below with reference to  FIGS. 50A, 50B, and 51 . 
       FIGS. 50A and 50B  are diagrams illustrating operation of a driving assistance system during a left turn according to the thirteenth embodiment of the present disclosure. 
     Referring to  FIGS. 1, 3, and 50A , a host vehicle  12 - 1000  is waiting at an intersection to turn left. In this case, the driver may watch the left direction with respect to the intersection. The left direction that the driver is watching may be defined as a first direction, and the right direction, which is opposite to the first direction, may be defined as a second direction. A vehicle approaching the intersection from the first direction may be defined as a first third-party vehicle  12 - 1200   a , and a vehicle approaching the intersection from the second direction may be defined as a second third-party vehicle  12 - 1200   b . The direction that the driver is watching may be sensed through a driver monitoring camera  316  disposed inside the vehicle. The driver monitoring camera  316  may sense a heading direction of the driver&#39;s face or a viewing direction for the driver&#39;s eyes to sense the direction that the driver is watching. The driver monitoring camera  316  may be an element in the MCU level. 
     The driver may sense an object approaching from the first direction and control the host vehicle  12 - 1000 , and a range in which the driver can directly control the host vehicle  12 - 1000  may be defined as a driver control range  12 - 1300   a . When there is a possibility of collision between the host vehicle  12 - 1000  and a third-party vehicle in the driver control range  12 - 1300   a , an ECU  12 - 320  may control a driver warning controller  12 - 331  to issue a warning. The vehicle camera system  1  may sense an object approaching from the second direction, which the driver is not watching, and the ECU  12 - 320  may control a steering controller  12 - 334  and a brake controller  12 - 337  through data acquired by the vehicle camera system  1  to control the steering and braking of the host vehicle  12 - 1000 . In this case, a range in which the ECU  12 - 320  can control the host vehicle may be defined as a system control range  12 - 1300   b . That is, the ECU  12 - 320  may sense the second direction, which is opposite to the first direction that the driver is watching and may control the host vehicle  12 - 1000  when there is a possibility of collision in the second direction. 
     The ECU  12 - 320  may determine, on a level basis, collision risk possibilities between the host vehicle and third-party vehicles  12 - 1200   a  and  12 - 1200   b  though data regarding whether the third-party vehicles  12 - 1200   a  and  12 - 1200   b  are approaching, which is acquired by the camera system  1 . The camera system  1  may measure the relative speeds of the third-party vehicles  12 - 1200   a  and  12 - 1200   b  approaching the host vehicle  12 - 1000  and the distances between the host vehicle  12 - 1000  and the third-party vehicles  12 - 1200   a  and  12 - 1200   b . The ECU  12 - 320  may set levels for the collision risk possibilities through the relative speeds between the host vehicle  12 - 1000  and the third-party vehicles  12 - 1200   a  and  12 - 1200   b  approaching the host vehicle  12 - 1000  and the distances between the host vehicle  12 - 1000  and the third-party vehicles  12 - 1200   a  and  12 - 1200   b . For example, when the distance is smaller than a pre-determined distance and the speed is higher than a pre-determined relative speed, the ECU  12 - 320  may determine that this situation corresponds to a high collision risk possibility level. When the distance is larger than the pre-determined distance and the speed is lower than the pre-determined relative speed, the ECU  12 - 320  may determine that this situation corresponds to a low collision risk possibility level. However, the criterion is merely an example and may be variously preset. When a collision risk level in the driver control range  12 - 1300   a  is the same as a collision risk level in the system control range  12 - 1300   b , the ECU  12 - 320  may determine that a collision risk is higher in the system control range  12 - 1300   b  than in the driver control range  12 - 1300   a . That is, the ECU  12 - 320  may mainly control a risk of collision that may occur beyond a driver controllable range. 
     Unlike the above-described example, the ECU  12 - 320  may control the hot vehicle  12 - 1000  unlike the driver&#39;s control when there is high collision possibility in the driver control range  12 - 1300   a . That is, when there is no collision possibility in the system control range  12 - 1300   b  but there is high collision possibility in the driver control range  12 - 1300 , the ECU  12 - 320  may be set to issue a warning as well as to control the steering and braking of the host vehicle  12 - 1000 . 
     Referring to  FIG. 50B , the driver may turn left at an intersection while sensing the first third-party vehicle  12 - 1200   a  located in the first direction. In this case, the vehicle camera system  1  may sense the presence of the second third-party vehicle  12 - 1200   b  approaching the host vehicle  12 - 1000 , and the ECU  12 - 320  may determine a possibility of collision between the host vehicle  12 - 1000  and the second third-party vehicle  12 - 1200   b . When a collision is expected to occur within the system control range  12 - 1300   b , the ECU  12 - 320  may control the steering and braking of the host vehicle  12 - 1000  to prevent a collision between the host vehicle  12 - 1000  and the second third-party vehicle  12 - 1200   b.    
       FIG. 51  is a diagram illustrating operation of the driving assistance system during a right turn according to the thirteenth embodiment of the present disclosure. For simplicity of description, a repetitive description of those described with reference to  FIGS. 50A and 50B  will be omitted. 
     Referring to  FIGS. 1, 3, and 51 , a host vehicle  12 - 1000  is waiting at an intersection to turn right. In this case, the driver may watch the right direction with respect to the intersection. The right direction that the driver is watching may be defined as a first direction, and the left direction, which is opposite to the first direction, may be defined as a second direction. The driver may sense an object approaching from the first direction and control the host vehicle  12 - 1000 , and a range in which the driver can directly control the host vehicle  12 - 1000  may be defined as a driver control range  12 - 1300   a . When there is a possibility of collision between the host vehicle  12 - 1000  and a third-party vehicle in the driver control range  12 - 1300   a , the ECU  12 - 320  may control the driver warning controller  12 - 331  to issue a warning. The vehicle camera system  1  may sense an object approaching from the second direction, which the driver is not watching, and the ECU  12 - 320  may control the steering controller  12 - 334  and the brake controller  12 - 337  through data acquired by the vehicle camera system  1  to control the steering an braking of the host vehicle  12 - 1000 . In this case, a range in which the ECU  12 - 320  can control the host vehicle may be defined as a system control range  12 - 1300   b.    
     The driver may turn left at the intersection while sensing the object  12 - 1200   b  located in the first direction. The object  12 - 1200   b  may be a vehicle, a pedestrian, a bicyclist, or the like. In this case, the vehicle camera system  1  may sense the presence of the third-party vehicle  12 - 1200   a  approaching the host vehicle  12 - 1000 , and the ECU  12 - 320  may determine a possibility of collision between the host vehicle  12 - 1000  and the third-party vehicle  12 - 1200   a . When a collision is expected to occur within the system control range  12 - 1300   b , the ECU  12 - 320  may control the steering and braking of the host vehicle  12 - 1000  to prevent a collision between the host vehicle  12 - 1000  and the third-party vehicle  12 - 1200   a.    
     Unlike the above-described example, the driver may watch a direction opposite to a direction in which the host vehicle  12 - 1000  is to travel. In this case, the ECU  12 - 320  may control the camera system  1  to watch a vehicle traveling direction, which is opposite to a direction that the driver is watching. The ECU  12 - 320  may determine both of a possibility of collision that may occur in the direction in which the vehicle is traveling and a possibility of collision that may occur in the direction that the driver is watching and may control the steering and braking of the host vehicle  12 - 1000  when there is a collision possibility in the vehicle traveling direction. Also, the ECU  12 - 320  may issue a warning where there is a collision possibility in the direction that the driver is watching. 
     In one or more exemplary embodiments, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions can be stored on or transmitted as one or more instructions or code on a computer-readable medium. Computer-readable media include all of communication media and computer storage media including any medium for facilitating transfer of a computer program from one place to another place. Storage media may be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media. 
     When exemplary embodiments are implemented by program code or code segments, each code segment may represent a procedure, a function, a subprogram, a program, a routine, a subroutine, a module, a software package, a class, or any combination of instructions, data structures, or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters, or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc. Additionally, in some aspects, the steps and/or operations of a method or algorithm may reside as one or any combination or set of codes and/or instructions on a machine-readable medium and/or computer-readable medium, which may be incorporated into a computer program product. 
     For a software implementation, the techniques described herein may be implemented with modules (e.g., procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in memory units and executed by processors. The memory unit may be implemented within the processor or external to the processor, in which case it can be communicatively coupled to the processor via various means as is known in the art. 
     For a hardware implementation, the processing units may be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, electronic devices, other electronic units designed to perform the functions described herein, or a combination thereof. 
     What has been described above includes examples of one or more aspects. It is, of course, not possible to describe every conceivable combination of components or methodologies for purposes of describing the aforementioned aspects, but one of ordinary skill in the art may recognize that many further combinations and permutations of various aspects are possible. Accordingly, the described aspects are intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, to the extent that the term “includes” is used in either the detailed description or the claims, such term is intended to be inclusive in a manner similar to the term “comprising” as “comprising” is interpreted when employed as a transitional word in a claim. 
     The terms to “infer” or “inference”, as used herein, refer generally to the process of reasoning about or inferring states of the system, environment, and/or user from a set of observations as captured via events and/or data. Inference can be employed to identify a specific context or action, or can generate a probability distribution over states, for example. The inference can be probabilistic, that is, the computation of a probability distribution over states of interest based on a consideration of data and events. Inference can also refer to techniques employed for composing higher-level events from a set of events and/or data. Such inference results in the construction of new events or actions from a set of observed events and/or stored event data whether or not the events are correlated in close temporal proximity, and whether the events and data come from one or several event and data sources. 
     As used herein, the terms “component,” “module,” “system,” and the like are intended to refer to a computer-related entity, either hardware, firmware, a combination of hardware and software, software, or software in execution. For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and/or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components can reside within a process and/or thread of execution and a component may be localized on one computer and/or distributed between two or more computers. In addition, these components can execute from various computer readable media having various data structures stored thereon. The components may communicate by way of local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from one to component interacting with another component in a local system, distributed system, and/or across a network, such as the Internet, with other systems by way of the signal).