Patent Publication Number: US-2023141584-A1

Title: Apparatus for displaying at least one virtual lane line based on environmental condition and method of controlling same

Description:
Pursuant to 35 U.S.C. § 119(a), this application claims the benefit of Korean Patent Application No. 10-2021-0153203, filed on Nov. 9, 2021, which is hereby incorporated by reference as if fully set forth herein. 
     BACKGROUND OF THE DISCLOSURE 
     Field of the Disclosure 
     The present embodiments are applicable to vehicles of all fields and, more particularly, to all systems related to vehicles, for displaying virtual lane lines on the interior or exterior of a vehicle based on various environmental conditions. 
     Discussion of the Related Art 
     A survey in the year 2020 by the Korea Transportation Safety Authority showed that the fatality rate of traffic accidents on rainy days was 37.5% higher than on sunny days. 
     Meanwhile, Korea Expressway Corporation is trying to expand the “lane lines clearly visible in rainy weather” to all sections of the expressway in order to secure driving safety on the highway even on rainy days. The “lane lines clearly visible in rainy weather” uses a functional paint mixed with rain-type glass beads. This paint is expected to provide a safer driving environment to a certain degree than a conventional environment because lane lines are clearly visible by light specularly reflected by the glass beads even on wet lane lines and durability is high. 
     However, it is still difficult for even an experienced driver to accurately recognize and identify actual lane lines according to the driver’s eyesight or in other poor driving environments (e.g., in snowy weather, night driving, or sunlight/sunset environments) in addition to rainy weather. 
     SUMMARY OF THE DISCLOSURE 
     Accordingly, the present disclosure is directed to an apparatus for displaying at least one virtual lane line based on an environmental condition and a method of controlling the same that substantially obviate one or more problems due to limitations and disadvantages of the related art. 
     An embodiment of the present disclosure is to provide a system for providing optimal virtual lane lines to a driver based on various driving/traveling environmental conditions. 
     Another embodiment of the present disclosure intends to use an augmented reality (AR) head-up display (HUD) system and a road irradiation headlamp by an organic combination based on a specific condition. 
     Another embodiment of the present disclosure is to more accurately detect information about actual lane lines through vehicle-to-everything (V2X) communication with nearby vehicles when an ego vehicle has difficulty in recognizing the actual lane lines and to provide virtual lane lines based on the information. 
     The objects to be achieved by the present disclosure are not limited to what has been particularly described hereinabove and other objects not described herein will be more clearly understood by persons skilled in the art from the following detailed description. 
     To achieve these objects and other advantages and in accordance with the purpose of the disclosure, as embodied and broadly described herein, a method of controlling an apparatus for displaying at least one virtual lane line based on an environmental condition includes recognizing an actual lane line of a vehicle traveling direction through at least one sensor, determining whether a head-up display (HUD) has been installed in a vehicle, upon determining that the HUD has been installed in the vehicle, displaying a first virtual lane line corresponding to the recognized actual lane line through the HUD and displaying a second virtual lane line corresponding to the recognized actual lane line on a road surface through a headlamp, and upon determining that the HUD has not been installed in the vehicle, displaying only a third virtual lane line corresponding to the recognized actual lane line through the headlamp. 
     The first virtual lane line may correspond to a first actual lane line closest to the vehicle based on the vehicle traveling direction, and the second virtual lane line may correspond to a second actual lane line located farther than the first actual lane line based on the vehicle traveling direction. 
     The method may further include determining whether a current environment is a sunrise or sunset environment through the at least one sensor, and upon determining that the current environment is the sunrise or sunset environment, determining whether a sun visor attached to the vehicle has been opened or closed. 
     The method may further include, upon determining that the sun visor attached to the vehicle is in an opened state, performing a control operation to display the virtual lane lines with a first brightness and a first thickness, and upon determining that the sun visor attached to the vehicle is in a closed state, performing a control operation to display the virtual lane lines with a second brightness and a second thickness. The first brightness may be higher than the second brightness and the first thickness may be thicker than the second thickness. 
     The method may further include determining whether surroundings of the vehicle are in a rainy state through the at least one sensor, and upon determining that the surroundings of the vehicle are in a rainy state, performing a control operation to display the virtual lane lines with a third brightness and a third thickness regardless of whether the sun visor has been opened or closed. The third brightness may correspond to a maximum brightness value relative to the first brightness and the second brightness, and the third thickness may correspond to a maximum thickness value relative to the first thickness and the second thickness. 
     The method may further include determining whether a consecutive actual lane line on the road surface is processed as a straight line by connecting three or more line segments corresponding to the actual lane line based on a preset reference stored in a memory, and upon determining that the consecutive actual lane line is not processed as the straight line, requesting at least one nearby vehicle traveling on a right side or a left side to transmit lane line information. Lane line information having highest accuracy may be used out of lane line information received from the at least one nearby vehicle based on the preset reference stored in the memory. 
     In another aspect of the present disclosure, a computer readable recording medium storing data for displaying at least one virtual lane line based on an environmental condition is configured to process data for an actual lane line of a vehicle traveling direction recognized through at least one sensor, process data for determining whether a head-up display (HUD) has been installed in a vehicle, upon determining that the HUD has been installed in the vehicle, process data for displaying a first virtual lane line corresponding to the recognized actual lane line through the HUD and displaying a second virtual lane line corresponding to the recognized actual lane line on a road surface through a headlamp, and upon determining that the HUD has not been installed in the vehicle, process data for displaying only the a third virtual lane line corresponding to the recognized actual lane line through the headlamp. 
     In another aspect of the present disclosure, an apparatus for displaying at least one virtual lane line based on to an environmental condition includes a sensor configured to recognize an actual lane line of a vehicle traveling direction, and a controller configured to determine whether a head-up display (HUD) has been installed in a vehicle. The controller may perform, upon determining that the HUD has been installed in the vehicle, a control operation to display a first virtual lane line corresponding to the recognized actual lane line through the HUD and display a second virtual lane line corresponding to the recognized actual lane line on a road surface through a headlamp, and the controller may perform, upon determining that the HUD has not been installed in the vehicle, a control operation to display only a third virtual lane line corresponding to the recognized actual lane line through the headlamp. 
     It is to be understood that both the foregoing general description and the following detailed description of the present disclosure are exemplary and explanatory and are intended to provide further explanation of the disclosure as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the disclosure and together with the description serve to explain the principle of the disclosure. In the drawings: 
         FIG.  1    is an overall block diagram of an autonomous driving control system to which an autonomous driving apparatus according to any one of embodiments of the present disclosure is applicable; 
         FIG.  2    is a diagram illustrating an example in which an autonomous driving apparatus according to any one of embodiments of the present disclosure is applied to a vehicle; 
         FIG.  3    is a flowchart illustrating in detail a method of controlling an apparatus for displaying at least one virtual lane line based on an environmental condition according to any one of embodiments of the present disclosure; 
         FIGS.  4 A and  4 B  are diagrams illustrating in detail steps S 306  and S 305  illustrated in  FIG.  3   , respectively; 
         FIGS.  5 A and  5 B  are diagrams illustrating in detail steps S 310  and S 312  illustrated in  FIG.  3   , respectively; 
         FIG.  6    is a diagram illustrating in more detail steps S 302  and S 303  illustrated in  FIG.  3   ; and 
         FIG.  7    is a block diagram illustrating an apparatus for displaying at least one virtual lane line based on an environmental condition according to any one of embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that the present disclosure may be easily realized by those skilled in the art. However, the present disclosure may be achieved in various different forms and is not limited to the embodiments described herein. In the drawings, parts that are not related to a description of the present disclosure are omitted to clearly explain the present disclosure and similar reference numbers will be used throughout this specification to refer to similar parts. 
     In the specification, when a part “includes” an element, it means that the part may further include another element rather than excluding another element unless otherwise mentioned. 
       FIG.  1    is an overall block diagram of an autonomous driving control system to which an autonomous driving apparatus according to any one of embodiments of the present disclosure is applicable.  FIG.  2    is a diagram illustrating an example in which an autonomous driving apparatus according to any one of embodiments of the present disclosure is applied to a vehicle. 
     First, a structure and function of an autonomous driving control system (e.g., an autonomous driving vehicle) to which an autonomous driving apparatus according to the present embodiments is applicable will be described with reference to  FIGS.  1  and  2   . 
     As illustrated in  FIG.  1   , an autonomous driving vehicle  1000  may be implemented based on an autonomous driving integrated controller  600  that transmits and receives data necessary for autonomous driving control of a vehicle through a driving information input interface  101 , a traveling information input interface  201 , an occupant output interface  301 , and a vehicle control output interface  401 . However, the autonomous driving integrated controller  600  may also be referred to herein as a controller, a processor, or, simply, a controller. 
     The autonomous driving integrated controller  600  may obtain, through the driving information input interface  101 , driving information based on manipulation of an occupant for a user input unit  100  in an autonomous driving mode or manual driving mode of a vehicle. As illustrated in  FIG.  1   , the user input unit  100  may include a driving mode switch  110  and a control panel  120  (e.g., a navigation terminal mounted on the vehicle or a smartphone or tablet computer owned by the occupant). Accordingly, driving information may include driving mode information and navigation information of a vehicle. 
     For example, a driving mode (i.e., an autonomous driving mode/manual driving mode or a sports mode/eco mode/safety mode/normal mode) of the vehicle determined by manipulation of the occupant for the driving mode switch  110  may be transmitted to the autonomous driving integrated controller  600  through the driving information input interface  101  as the driving information. 
     Furthermore, navigation information, such as the destination of the occupant input through the control panel  120  and a path up to the destination (e.g., the shortest path or preference path, selected by the occupant, among candidate paths up to the destination), may be transmitted to the autonomous driving integrated controller  600  through the driving information input interface  101  as the driving information. 
     The control panel  120  may be implemented as a touchscreen panel that provides a user interface (UI) through which the occupant inputs or modifies information for autonomous driving control of the vehicle. In this case, the driving mode switch  110  may be implemented as touch buttons on the control panel  120 . 
     In addition, the autonomous driving integrated controller  600  may obtain traveling information indicative of a driving state of the vehicle through the traveling information input interface  201 . The traveling information may include a steering angle formed when the occupant manipulates a steering wheel, an accelerator pedal stroke or brake pedal stroke formed when the occupant depresses an accelerator pedal or brake pedal, and various types of information indicative of driving states and behaviors of the vehicle, such as a vehicle speed, acceleration, a yaw, a pitch, and a roll formed in the vehicle. The traveling information may be detected by a traveling information detection unit  200 , including a steering angle sensor  210 , an accelerator position sensor (APS)/pedal travel sensor (PTS)  220 , a vehicle speed sensor  230 , an acceleration sensor  240 , and a yaw/pitch/roll sensor  250 , as illustrated in  FIG.  1   . 
     Furthermore, the traveling information of the vehicle may include location information of the vehicle. The location information of the vehicle may be obtained through a global positioning system (GPS) receiver  260  applied to the vehicle. Such traveling information may be transmitted to the autonomous driving integrated controller  600  through the traveling information input interface  201  and may be used to control the driving of the vehicle in the autonomous driving mode or manual driving mode of the vehicle. 
     The autonomous driving integrated controller  600  may transmit driving state information provided to the occupant to an output unit  300  through the occupant output interface  301  in the autonomous driving mode or manual driving mode of the vehicle. That is, the autonomous driving integrated controller  600  transmits the driving state information of the vehicle to the output unit  300  so that the occupant may check the autonomous driving state or manual driving state of the vehicle based on the driving state information output through the output unit  300 . The driving state information may include various types of information indicative of driving states of the vehicle, such as a current driving mode, transmission range, and speed of the vehicle. 
     If it is determined that it is necessary to warn a driver in the autonomous driving mode or manual driving mode of the vehicle along with the above driving state information, the autonomous driving integrated controller  600  transmits warning information to the output unit  300  through the occupant output interface  301  so that the output unit  300  may output a warning to the driver. In order to output such driving state information and warning information acoustically and visually, the output unit  300  may include a speaker  310  and a display  320  as illustrated in  FIG.  1   . In this case, the display  320  may be implemented as the same device as the control panel  120  or may be implemented as an independent device separated from the control panel  120 . 
     Furthermore, the autonomous driving integrated controller  600  may transmit control information for driving control of the vehicle to a lower control system  400 , applied to the vehicle, through the vehicle control output interface  401  in the autonomous driving mode or manual driving mode of the vehicle. As illustrated in  FIG.  1   , the lower control system  400  for driving control of the vehicle may include an engine control system  410 , a braking control system  420 , and a steering control system  430 . The autonomous driving integrated controller  600  may transmit engine control information, braking control information, and steering control information, as the control information, to the respective lower control systems  410 ,  420 , and  430  through the vehicle control output interface  401 . Accordingly, the engine control system  410  may control the speed and acceleration of the vehicle by increasing or decreasing fuel supplied to an engine. The braking control system  420  may control the braking of the vehicle by controlling braking power of the vehicle. The steering control system  430  may control the steering of the vehicle through a steering device (e.g., motor driven power steering (MDPS) system) applied to the vehicle. 
     As described above, the autonomous driving integrated controller  600  according to the present embodiment may obtain the driving information based on manipulation of the driver and the traveling information indicative of the driving state of the vehicle through the driving information input interface  101  and the traveling information input interface  201 , respectively, and transmit the driving state information and the warning information, generated based on an autonomous driving algorithm, to the output unit  300  through the occupant output interface  301 . In addition, the autonomous driving integrated controller  600  may transmit the control information generated based on the autonomous driving algorithm to the lower control system  400  through the vehicle control output interface  401  so that driving control of the vehicle is performed. 
     In order to guarantee stable autonomous driving of the vehicle, it is necessary to continuously monitor the driving state of the vehicle by accurately measuring a driving environment of the vehicle and to control driving based on the measured driving environment. To this end, as illustrated in  FIG.  1   , the autonomous driving apparatus according to the present embodiment may include a sensor unit  500  for detecting a nearby object of the vehicle, such as a nearby vehicle, pedestrian, road, or fixed facility (e.g., a signal light, a signpost, a traffic sign, or a construction fence). 
     The sensor unit  500  may include one or more of a LiDAR sensor  510 , a radar sensor  520 , or a camera sensor  530 , in order to detect a nearby object outside the vehicle, as illustrated in  FIG.  1   . 
     The LiDAR sensor  510  may transmit a laser signal to the periphery of the vehicle and detect a nearby object outside the vehicle by receiving a signal reflected and returning from a corresponding object. The LiDAR sensor  510  may detect a nearby object located within the ranges of a preset distance, a preset vertical field of view, and a preset horizontal field of view, which are predefined depending on specifications thereof. The LiDAR sensor  510  may include a front LiDAR sensor  511 , a top LiDAR sensor  512 , and a rear LiDAR sensor  513  installed at the front, top, and rear of the vehicle, respectively, but the installation location of each LiDAR sensor and the number of LiDAR sensors installed are not limited to a specific embodiment. A threshold for determining the validity of a laser signal reflected and returning from a corresponding object may be previously stored in a memory (not illustrated) of the autonomous driving integrated controller  600 . The autonomous driving integrated controller  600  may determine a location (including a distance to a corresponding object), speed, and moving direction of the corresponding object using a method of measuring time taken for a laser signal, transmitted through the LiDAR sensor  510 , to be reflected and returning from the corresponding object. 
     The radar sensor  520  may radiate electromagnetic waves around the vehicle and detect a nearby object outside the vehicle by receiving a signal reflected and returning from a corresponding object. The radar sensor  520  may detect a nearby object within the ranges of a preset distance, a preset vertical field of view, and a preset horizontal field of view, which are predefined depending on specifications thereof. The radar sensor  520  may include a front radar sensor  521 , a left radar sensor  522 , a right radar sensor  523 , and a rear radar sensor  524  installed at the front, left, right, and rear of the vehicle, respectively, but the installation location of each radar sensor and the number of radar sensors installed are not limited to a specific embodiment. The autonomous driving integrated controller  600  may determine a location (including a distance to a corresponding object), speed, and moving direction of the corresponding object using a method of analyzing power of electromagnetic waves transmitted and received through the radar sensor  520 . 
     The camera sensor  530  may detect a nearby object outside the vehicle by photographing the periphery of the vehicle and detect a nearby object within the ranges of a preset distance, a preset vertical field of view, and a preset horizontal field of view, which are predefined depending on specifications thereof. 
     The camera sensor  530  may include a front camera sensor  531 , a left camera sensor  532 , a right camera sensor  533 , and a rear camera sensor  534  installed at the front, left, right, and rear of the vehicle, respectively, but the installation location of each camera sensor and the number of camera sensors installed are not limited to a specific embodiment. The autonomous driving integrated controller  600  may determine a location (including a distance to a corresponding object), speed, and moving direction of the corresponding object by applying predefined image processing to an image captured by the camera sensor  530 . 
     In addition, an internal camera sensor  535  for capturing the inside of the vehicle may be mounted at a predetermined location (e.g., rear view mirror) within the vehicle. The autonomous driving integrated controller  600  may monitor a behavior and state of the occupant based on an image captured by the internal camera sensor  535  and output guidance or a warning to the occupant through the output unit  300 . 
     As illustrated in  FIG.  1   , the sensor unit  500  may further include an ultrasonic sensor  540  in addition to the LiDAR sensor  510 , the radar sensor  520 , and the camera sensor  530  and further adopt various types of sensors for detecting a nearby object of the vehicle along with the sensors. 
       FIG.  2    illustrates an example in which, in order to aid in understanding the present embodiment, the front LiDAR sensor  511  or the front radar sensor  521  is installed at the front of the vehicle, the rear LiDAR sensor  513  or the rear radar sensor  524  is installed at the rear of the vehicle, and the front camera sensor  531 , the left camera sensor  532 , the right camera sensor  533 , and the rear camera sensor  534  are installed at the front, left, right, and rear of the vehicle, respectively. However, as described above, the installation location of each sensor and the number of sensors installed are not limited to a specific embodiment. 
     Furthermore, in order to determine a state of the occupant within the vehicle, the sensor unit  500  may further include a bio sensor for detecting bio signals (e.g., heart rate, electrocardiogram, respiration, blood pressure, body temperature, electroencephalogram, photoplethysmography (or pulse wave), and blood sugar) of the occupant. The bio sensor may include a heart rate sensor, an electrocardiogram sensor, a respiration sensor, a blood pressure sensor, a body temperature sensor, an electroencephalogram sensor, a photoplethysmography sensor, and a blood sugar sensor. 
     Finally, the sensor unit  500  additionally includes a microphone  550  having an internal microphone  551  and an external microphone  552  used for different purposes. 
     The internal microphone  551  may be used, for example, to analyze the voice of the occupant in the autonomous driving vehicle  1000  based on Al or to immediately respond to a direct voice command of the occupant. 
     In contrast, the external microphone  552  may be used, for example, to appropriately respond to safe driving by analyzing various sounds generated from the outside of the autonomous driving vehicle  1000  using various analysis tools such as deep learning. 
     For reference, the symbols illustrated in  FIG.  2    may perform the same or similar functions as those illustrated in  FIG.  1   .  FIG.  2    illustrates in more detail a relative positional relationship of each component (based on the interior of the autonomous driving vehicle  1000 ) as compared with  FIG.  1   . 
     In  FIGS.  1  and  2   , the vehicle equipped with an autonomous driving function has been exemplarily described as an embodiment of the present disclosure. However, the present disclosure may also be applied to a general vehicle having only a part of the autonomous driving function or no autonomous driving function at all. 
       FIG.  3    is a flowchart illustrating in detail a method of controlling an apparatus for displaying at least one virtual lane line based on an environmental condition according to any one of embodiments of the present disclosure. An embodiment of the present disclosure is to provide a lane line visualization convenience system through virtual lane lines in a poor environment of vehicle driving (e.g., in a rainy, snowy, night driving, sunrise, or sunset environment). In particular, as illustrated in  FIG.  3   , a driver may more accurately recognize virtual lane lines by adaptively using an augmented reality (AR) head-up display (HUD) function and road irradiation headlamps. In addition, data of virtual lane lines may be differently processed according to various environmental conditions, so that an optimized driving environment may be provided and the rate of vehicle accidents in a poor environment such as rainy weather may be significantly reduced. 
     First, as illustrated in  FIG.  3   , the apparatus for displaying at least one virtual lane line based on an environmental condition according to an embodiment of the present disclosure (which may be installed in software/hardware in a vehicle) determines whether a vehicle succeeds in recognizing an actual lane line of a vehicle traveling direction through at least one sensor (S 301 ). This process may be implemented using the sensors and the cameras previously described with reference to  FIGS.  1  and  2   . 
     When the actual lane line is recognized as a result of the determination (S 301 ), the apparatus determines whether a HUD is installed in the vehicle (S 304 ). 
     As a result of the determination (S 304 ), if the vehicle is equipped with the HUD, the apparatus displays a first virtual lane line corresponding to the recognized actual lane line through the HUD and displays a second virtual lane line corresponding to the recognized actual lane line is displayed on a road surface through a headlamp (S 306 ). 
     An embodiment related to step S 306  is illustrated in more detail in  FIG.  4 A . In  FIG.  4 A , reference numeral  401  corresponds to a steering wheel generally installed in a vehicle, and reference numeral  402  corresponds to an audio, video, navigation (AVN) unit installed in the vehicle. 
     Reference numeral  403  denotes a HUD installed in the vehicle. The apparatus performs a control operation to display a first virtual lane line  404  corresponding to the actual lane line through the HUD  403 . The first virtual lane line  404  corresponds to a first actual lane line closest to the vehicle based on a vehicle traveling direction. 
     Reference numeral  400  corresponds to a windshield of the actual vehicle, and a second virtual lane line  405  is displayed on the road surface through the headlamp installed in the vehicle. Additionally, an arrow  406  indicating the vehicle traveling direction may be displayed. 
     The second virtual lane line  405  illustrated in  FIG.  4 A  corresponds to a second actual lane line located farther than the first actual lane line corresponding to the first virtual lane line  404  based on the vehicle traveling direction. 
     In particular, when the vehicle is equipped with the HUD, only a part of virtual lane lines may be displayed through the headlamp, and the remaining part may be displayed through the HUD, which has a technical effect that may prevent power consumption of the headlamp or overload of data processing. 
     In addition, if the virtual lane line through the headlamp is displayed at the position of the virtual lane line displayed through the HUD, this may rather disturb a driver of the vehicle. Therefore, separately displaying the virtual lane line through the HUD and the virtual lane line through the headlamp is also a feature and effect of the present disclosure. 
     On the other hand, if the HUD is not installed in the vehicle as a result of the determination (S 304 ), the apparatus displays only a third virtual lane line corresponding to the actual lane line recognized in step S 301  through the headlamp (S 305 ). 
     An embodiment related to step S 305  is illustrated in more detail in  FIG.  4 B . A virtual lane line  414  illustrated in  FIG.  4 B  means a virtual lane line displayed on the road surface through the headlamp. 
     The apparatus determines whether a current environment is a sunrise or sunset environment through at least one sensor installed in the vehicle (S 307 ). For example, receiving information about a sunrise and/or sunset time using a front camera, a drive video record system (DVRS), or an illuminance sensor or based on a GPS through a communication network is also within the scope of the present disclosure. Considering the sunrise or sunset time is to correct the brightness/thickness of the virtual lane lines graphically displayed according to the sunrise/sunset environment. 
     If the current environment corresponds to the sunrise or sunset environment as a result of the determination (S 307 ), the apparatus additionally determines whether a sun visor attached to the vehicle has been opened or closed (S 308 ). 
     If the sun visor attached to the vehicle is in an opened state as a result of the determination (S 308 ), the apparatus performs a control operation to display the virtual lane lines in step S 305  or S 306  with a first brightness and a first thickness (S 309 ). 
     On the other hand, if the sun visor attached to the vehicle is in a closed state as a result of the determination (S 308 ), the apparatus performs a control operation to display the virtual lane lines in step S 305  or S 306  with a second brightness and a second thickness (S 310 ). 
     An embodiment related to step S 310  is illustrated in more detail in  FIG.  5 A . 
     The driver may check the virtual lane lines displayed on the HUD  503  and the road surface through a vehicle windshield  500 . Both a virtual lane line  504  displayed through a HUD  503  and a virtual lane line  505  displayed through the headlamp are designed to increase brightness and thickness. That is, in the sunrise/sunset environment, when the sun visor is closed, since it is difficult for the driver to recognize lane lines more accurately and quickly, the first brightness in step S 309  is higher than the second brightness in step S 310  and the first thickness in step S 309  is thicker than the second thickness in step S 310 . 
     Furthermore, according to an embodiment of the present disclosure, the apparatus determines whether the surroundings of the vehicle are in a rainy state through at least one sensor (S 311 ). The rainy state exemplified herein may include other bad weather conditions such as snowy weather. Step S 311  may be determined based on data collected through an automatic light sensor, a rain sensor, a front camera, and a DVRS camera or based on predicted weather information received through a communication network based on GPS information. 
     If the surroundings of the vehicle are in a rainy state as a result of the determination (S 311 ), the apparatus performs a control operation to display the virtual lane lines with a third brightness (e.g., a maximum brightness value) and a third thickness (e.g., a maximum thickness value) (S 312 ) regardless of whether the sun visor has been opened or closed. 
     An embodiment related to step S 312  is illustrated in more detail in  FIG.  5 B . 
     While  FIG.  5 B  illustrates that only a virtual lane line  514  displayed through the HUD is displayed with a maximum brightness and a maximum thickness, a virtual lane line displayed through the headlamp may be displayed with a maximum brightness and a maximum thickness. Alternatively, additionally displaying an arrow  515  indicating a current traveling direction of the vehicle or an arrow  516  indicating a planned traveling direction on the road surface through the headlamp may also fall within another scope of the present disclosure. 
     Meanwhile, the vehicle may fail to recognize the actual lane line due to performance limitations of the cameras and the sensor of the vehicle as a result of the determination (S 301 ). In this case, steps S 302  and S 303  may be performed as another embodiment. 
       FIG.  6    is a diagram illustrating in more detail steps S 302  and S 303  illustrated in  FIG.  3   . 
     First, a vehicle  610  according to an embodiment of the present disclosure determines whether a consecutive actual lane line (e.g., consisting of dotted lines) on a road surface may be processed (or recognized) as a straight line by connecting, for example, three or more line segments corresponding to the actual lane line, based on a preset reference stored in a memory. 
     If the vehicle  610  fails to recognize the lane line as the straight line when connecting three or more line segments as a result of the determination, the vehicle  610  requests at least one nearby vehicle  620  traveling on the right or left thereof to transmit lane line information (step S 302  of  FIG.  3   ). 
     The vehicle  610  according to an embodiment of the present disclosure is designed to use lane line information having the highest accuracy out of information received from one or more other vehicles based on the preset reference stored in the memory. Accordingly, when the vehicle  610  fails to recognize a lane line due to the low performance of the cameras/sensors thereof, the vehicle  610  may use lane line information of other vehicles equipped with high-performance cameras/sensors, so that there is an advantage in that accuracy may be improved. 
       FIG.  7    is a block diagram illustrating an apparatus for displaying at least one virtual lane line based on an environmental condition according to any one of embodiments of the present disclosure.  FIG.  7    may be supplementarily interpreted with reference to  FIGS.  1  to  6   . 
     A vehicle according to an embodiment of the present disclosure includes a controller  710 , an autonomous driving controller including sensors  720 , an AVN  730 , a V2X controller  740 , a ultra-wideband (UWB) smartkey module  750 , an AR HUD  760 , and a road display headlamp  770 . 
     The sensor  720  recognizes an actual lane line of a vehicle traveling direction. 
     The controller  710  determines whether a HUD is mounted in the vehicle. Here, for example, the HUD corresponds to the AR HUD  760  illustrated in  FIG.  7   . It is necessary for the controller  710  to identify whether the HUD is installed/uninstalled or is broken down depending on vehicles. Whether the HUD is out of order is determined by, for example, whether a response message is received after a request message is transmitted to the AR HUD  760 . 
     When the HUD is installed in the vehicle as a result of the determination, the controller  710  performs a control operation to display a first virtual lane line corresponding to the recognized actual lane line through the HUD  760  and to display a second virtual lane line corresponding to the recognized actual lane line on a road surface through the headlamp  770 . 
     If it is determined that the HUD  760  is not installed in the vehicle, the controller  710  performs a control operation to display only a third virtual lane line corresponding to the recognized actual lane line through the headlamp  770 . 
     The first virtual lane line corresponds to, for example, a first actual lane line closest to the vehicle based on the vehicle traveling direction, and the second virtual lane line corresponds to, for example, a second actual lane line located farther than the first actual lane line based on the vehicle traveling direction. 
     The controller  710  determines whether a current environment is a sunrise or sunset environment through the at least one sensor  720 . If it is determined that the current environment is the sunrise or sunset environment, the controller  710  determines whether a sun visor (not illustrated) attached to the vehicle has been opened or closed. 
     When the sun visor (not illustrated) attached to the vehicle is in an opened state, the controller  710  performs a control operation to display the virtual lane lines with a first brightness and a first thickness. When the sun visor (not illustrated) attached to the vehicle is in a closed state, the controller  710  performs a control operation to display the virtual lane lines with a second brightness and a second thickness. 
     The first brightness is higher than the second brightness and the first thickness is thicker than the second thickness. 
     The controller  710  determines whether the surroundings of the vehicle are in a rainy state through the at least one sensor  720 . If it is determined that the surroundings of the vehicle are in a rainy state, the controller  710  performs a control operation to display the virtual lane lines with a third brightness and a third thickness regardless of whether the sun visor (not illustrated) has been opened or closed. 
     The third brightness corresponds to a maximum brightness value relative to the first brightness and the second brightness, and the third thickness corresponds to a maximum thickness value relative to the first thickness and the second thickness. 
     The controller  710  determines whether a consecutive actual lane line on the road surface is processed as a straight line by connecting three or more segments corresponding to the actual lane line based on a preset reference stored in a memory (not illustrated). If it is determined that the consecutive actual lane line is not processed as the straight line, the controller  710  performs a control operation to request at least one nearby vehicle traveling on a right side or a left side of the vehicle to transmit lane line information through the V2X controller  740 . 
     The controller  710  uses lane line information having highest accuracy out of lane line information received from the at least one nearby vehicle based on the preset reference stored in the memory (not illustrated). 
     As another aspect of the present disclosure, the above-described proposal or operation of the disclosure may be provided as code which may be implemented, practiced, or executed by a “computer” (comprehensive concept including a system-on-chip (SoC) or a microprocessor) or as an application, a computer-readable storage medium, or a computer program product, which stores or includes the code, and this is also falls within the scope of the present disclosure. 
     For example, a computer-readable recording medium storing data for displaying at least one virtual lane line based on to an environmental condition processes data for an actual lane line of a vehicle traveling direction recognized through at least one sensor, processes data for determining whether a head-up display (HUD) has been installed in a vehicle, upon determining that the HUD has been installed in the vehicle, processes data for displaying a first virtual lane line corresponding to the recognized actual lane line through the HUD and displaying a second virtual lane line corresponding to the recognized actual lane line on a road surface through a headlamp, and upon determining that the HUD has not been installed in the vehicle, processes data for displaying only a third virtual lane line corresponding to the recognized actual lane line through the headlamp. 
     According to any one of the embodiments of the present disclosure, a vehicle accident may be prevented through convergence technology of an AR HUD and a road irradiation headlamp. 
     According to any one of the embodiments of the present disclosure, a system capable of adaptively controlling at least one of the AR HUD or the road irradiation headlamp according to a poor environment related to vehicle traveling is provided. 
     According to any one of the embodiments of the present disclosure, fatigue of a driver may be reduced due to virtual lane lines generated by the AR HUD and the road irradiation headlamp. 
     The effects that are achievable by the present disclosure are not limited to what has been particularly described hereinabove and other advantages not described herein will be more clearly understood by persons skilled in the art from the above description. 
     As described above, the detailed description of the embodiments of the present disclosure has been given to enable those skilled in the art to implement and practice the disclosure. Although the disclosure has been described with reference to the embodiments, those skilled in the art will appreciate that various modifications and variations may be made in the present disclosure without departing from the spirit or scope of the disclosure and the appended claims. For example, those skilled in the art may use constructions disclosed in the above-described embodiments in combination with each other. 
     Accordingly, the present disclosure should not be limited to the specific embodiments described herein, but should be accorded the broadest scope consistent with the principles and features disclosed herein.