Patent ID: 12227179

DESCRIPTION OF EMBODIMENTS

Hereinafter, a vehicle control device, a vehicle control method, and a storage medium according to an embodiment of the present invention will be described with reference to the accompanying drawings.

Entire Configuration

FIG.1is a diagram illustrating a configuration of a vehicle system1employing a vehicle control device according to an embodiment. A vehicle in which the vehicle system1is mounted (hereinafter referred to as a vehicle M) is, for example, a vehicle with two wheels, three wheels, or four wheels and a drive source thereof is an internal combustion engine such as a diesel engine or a gasoline engine, an electric motor, or a combination thereof. The electric motor operates using electric power generated by a power generator connected to the internal combustion engine or using electric power discharged from a secondary battery or a fuel cell. For example, an embodiment in which the vehicle control device is applied to an automated driving vehicle will be described in the following description. Automated driving is driving control which is performed by autonomously controlling one or both of steering and acceleration/deceleration of the vehicle M. The driving control of the vehicle M may include various types of driving support such as adaptive cruise control (ACC), and auto lane changing (ALC), lane keeping assistance system (LKAS). Partial or whole manual driving of an automated driving vehicle may be controlled by an occupant (a driver).

The vehicle system1includes, for example, a camera (an example of an image capturer)10, a radar device12, a Light Detection and Ranging (LIDAR) device14, an object recognition device16, a communication device20, a human-machine interface (HMI)30, a vehicle sensor40, a navigation device50, a map positioning unit (MPU)60, a driver monitoring camera70, a driving operator80, an automated driving control device100, a travel driving force output device200, a brake device210, and a steering device220. These devices or instruments are connected to each other via a multiplex communication line such as a controller area network (CAN) communication line, a serial communication line, a radio communication network, or the like. The configuration illustrated inFIG.1is only an example and a part of the configuration may be omitted or another configuration may be added thereto. A combination of the camera10, the radar device12, and the LIDAR device14is an example of an “external sensor ES.” The external sensor ES may include another detector that recognizes a surrounding situation of the vehicle, or may include the object recognition device16. The HMI30is an example of an “output device.” The automated driving control device100is an example of a “vehicle control device.”

The camera10is, for example, a digital camera using a solid-state imaging device such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The camera10is attached to an arbitrary position on the vehicle M. For example, when the front view of the vehicle M is imaged, the camera10is attached to an upper part of a front windshield, a rear surface of a rearview mirror, or the like. When the rear view of the vehicle M is imaged, the camera10is attached to an upper part of a rear windshield, a back door, or the like. When the lateral view and the rear-later view of the vehicle M is imaged, the camera10is attached to a door mirror or the like. The camera10images the surroundings of the vehicle M, for example, periodically and repeatedly. The camera10may be a stereoscopic camera. The camera10may include a plurality of cameras (for example, a first camera and a second camera), and may capture an image in the same direction using the plurality of cameras or may usually capture an image using the first camera and capture an image using the second camera or both the first camera and the second camera when predetermined conditions are satisfied. The predetermined conditions include, for example, a condition that lane markings (hereinafter referred to as markings) for defining a lane or the like included in a road on which the vehicle M travels from an image captured by the camera (hereinafter referred to as a camera image).

The radar device12radiates radio waves such as millimeter waves to the surroundings of the vehicle M, detects radio waves (reflected waves) reflected by an object, and detects at least a position (a distance and a direction) of the object. The radar device12is attached to an arbitrary position on the vehicle M. The radar device12may detect a position and a speed of an object using a frequency modulated continuous wave (FM-CW) method.

The LIDAR device14radiates light (or electromagnetic waves of wavelengths close to light) to the surroundings of the vehicle M and measures scattered light. The LIDAR device14detects a distance to an object on the basis of a time from radiation of light to reception of light. The radiated light is, for example, a pulse-like laser beam. The LIDAR device14is attached to an arbitrary position on the vehicle M.

The object recognition device16performs a sensor fusion process on results of detection from some or all of the camera10, the radar device12, and the LIDAR device14included in the external sensor ES and recognizes a position, a type, a speed, and the like of an object. The object recognition device16outputs the result of recognition to the automated driving control device100. The object recognition device16may output the results of detection from the camera10, the radar device12, and the LIDAR device14to the automated driving control device100without any change. The object recognition device16may be omitted from the vehicle system1.

The communication device20communicates with other vehicles near the vehicle M, for example, using a cellular network, a Wi-Fi network, Bluetooth (registered trademark), or dedicated short range communication (DSRC) or communicates with various server devices via radio base stations.

The HMI30presents various types of information to an occupant of the vehicle M and receives an input operation from the occupant under the control of an HMI controller170. The HMI30includes, for example, various display devices, speakers, switches, microphones, buzzers, touch panels, and keys. Examples of the display devices include a liquid crystal display (LCD) and an organic electroluminescence (EL) display device. The display device is provided in the vicinity of the front of a driver's seat (a seat closest to the steering wheel) on an instrument panel and is installed at a position which can be seen by an occupant through a gap of the steering wheel or over the steering wheel. The display device may be installed at the center of the instrument panel. The display device may be a head-up display (HUD). The HUD allows an occupant sitting on the driver's seat to see a virtual image by projecting an image to a part of a front windshield in front of the driver's seat. The display device displays an image which his generated by the HMI controller170which will be described later. The HMI30may include a driving switch that switches between automated driving and manual driving with an occupant intervening therein. Examples of the switch include a direction indicator switch32. The direction indicator switch32is provided, for example, on a steering column or the steering wheel. The direction indicator switch32is an example of an operator that receives, for example, an input of a lane change instruction for the vehicle M from an occupant.

The vehicle sensor40includes a vehicle speed sensor that detects a speed of the vehicle M, an acceleration sensor that detects an acceleration, a yaw rate sensor that detects an angular velocity around a vertical axis, and a direction sensor that detects a direction of the vehicle M. The vehicle sensor40may include a steering angle sensor that detects a steering angle of the vehicle M (which may be an angle of a steering wheel or an operating angle of the steering wheel). The vehicle sensor40may include a position sensor that acquires a position of the vehicle M. The position sensor is, for example, a sensor that acquires position information (longitude and latitude information) from a global positioning system (GPS) device. The position sensor may be a sensor that acquires position information using a global navigation satellite system (GNSS) receiver51of a navigation device50.

The navigation device50includes, for example, a GNSS receiver51, a navigation HMI52, and a route determiner53. The navigation device50stores first map information54in a storage device such as a hard disk drive (HDD) or a flash memory. The GNSS receiver51identifies a position of the vehicle M on the basis of signals received from GNSS satellites. The position of the vehicle M may be identified or complemented by an inertial navigation system (INS) using the output of the vehicle sensor40. The navigation HMI52includes a display device, a speaker, a touch panel, and keys. The navigation HMI52may be partially or wholly shared by the HMI30. For example, the route determiner53determines a route (hereinafter referred to as a route on a map) from the position of the vehicle M identified by the GNSS receiver51(or an input arbitrary position) to a destination input by an occupant using the navigation HMI52with reference to the first map information54. The first map information54includes, for example, information to which information on lanes for each road is added (hereinafter referred to as lane information). The lane information includes, for example, nodes indicating starting and ending of each road section and links indicating a road shape between nodes. The lane information may include the number of lanes (the number of parallel lanes) in a predetermined section such as a unit of road or an increase/decrease in the number of lanes and an increasing/decreasing direction of the number of lanes (information indicating on which side in an extending direction of a road the number of lanes increases or decreases). The first map information54may include a distance or a curvature of a road section, a road type (for example, an expressway or a regular road), and point of interest (POI) information. The route on a map is output to the MPU60. The navigation device50may perform route guidance using the navigation HMI52on the basis of the route on a map. The navigation device50may be realized, for example, by a function of a terminal device such as a smartphone or a tablet terminal which is carried by an occupant. The navigation device50may transmit a current position and a destination to a navigation server via the communication device20and acquire a route which is equivalent to the route on a map from the navigation server. The first map information54may be stored in a storage180instead of the navigation device50.

The MPU60includes, for example, a recommended lane determiner61. The recommended lane determiner61divides a route on a map provided from the navigation device50into a plurality of blocks (for example, every 100 [m] in a vehicle travel direction) and determines a recommended lane for each block with reference to lane information of the first map information54. The recommended lane determiner61may determine the recommended lane for each road stored in the first map information54. The recommended lane determiner61determines in which lane from the leftmost (or the rightmost) the vehicle is to travel. When there is a branching point in the route on a map, the recommended lane determiner61determines the recommended lane such that the vehicle M travels along a rational route for traveling to a branching destination.

The driver monitoring camera70is, for example, a digital camera using a solid-state imaging device such as a CCD or a CMOS. The driver monitoring camera70is attached to an arbitrary position on the vehicle M in a place and a direction in which the head of an occupant (hereinafter referred to as a driver) sitting on a driver's seat of the vehicle M can be imaged from the front (such that the face of the driver is imaged). For example, the driver monitoring camera70is attached to an upper part of a display device which is provided at the central part of an instrument panel of the vehicle M.

The driving operator80includes, for example, an accelerator pedal, a brake pedal, a shift lever, and other operators in addition to a steering wheel82. A sensor that detects an amount of operation or performing of an operation is attached to the driving operator80. Results of detection of the sensor are output to the automated driving control device100or output to some or all of the travel driving force output device200, the brake device210, and the steering device220. The steering wheel82is an example of an “operator that receives a driver's steering operation.” The operator does not have to have a ring shape and may have a shape of a deformed steering, a joystick, a button, or the like. A steering wheel grasp sensor84is attached to the steering wheel82. The steering wheel grasp sensor84is realized by a capacitance sensor or the like and outputs a signal indicating whether a driver grasps the steering wheel82(which means contacting the steering wheel with a force applied thereto) to the automated driving control device100.

The automated driving control device100includes, for example, a first controller120, a second controller160, an HMI controller170, and a storage180. The first controller120, the second controller160, and the HMI controller170are realized, for example, by causing a hardware processor such as a central processing unit (CPU) to execute a program (software). Some or all of such elements may be realized by hardware (which includes circuitry) such as a large scale integration (LSI), an application-specific integrated circuit (ASIC), or a field-programmable gate array (FPGA), or a graphics processing unit (GPU) or may be realized in cooperation of software and hardware. The program may be stored in a storage device (a storage device including a non-transitory storage medium) such as an HDD or a flash memory of the automated driving control device100in advance, or may be stored in a removable storage medium such as a DVD or a CD-ROM and installed in the HDD or the flash memory of the automated driving control device100by attaching the removable storage medium (non-transitory storage medium) to a drive device. A combination of a movement plan creator140and the second controller160is an example of a “driving controller.” The HMI controller170is an example of an “output controller.”

The storage180may be realized by the aforementioned various storage devices or a solid-state drive (SSD), an electrically erasable programmable read only memory (EEPROM), a read only memory (ROM), a random access memory (RAM), or the like. For example, a lane change correction table182, a lane increase/decrease correction table184, programs, and various types of other information are stored in the storage180. The lane change correction table182is a table which is referred to in order to correct a traveling lane of the vehicle M when the vehicle M performs a change of behavior such as lane change. The lane increase/decrease correction table184is a table which is referred to in order to correct the traveling lane of the vehicle M when the number of lanes of a road including the traveling lane of the vehicle M increases or decreases. Details of the tables will be described later. The first map information54may be stored in the storage180.

FIG.2is a diagram illustrating functional configurations of the first controller120and the second controller160according to the embodiment. The first controller120includes, for example, a recognizer130, a movement plan creator140, and a mode determiner150. For example, the first controller120realizes a function based on artificial intelligence (AI) and a function based on a predetermined model together. For example, a function of “recognizing a crossing” may be realized by performing recognition of a crossing based on deep learning or the like and recognition based on predetermined conditions (such as signals and road signs which can be pattern-matched) together, scoring both recognitions, and comprehensively evaluating the recognitions. Accordingly, reliability of automated driving is secured.

The recognizer130recognizes states such as a position, a speed, and an acceleration of an object near the vehicle M on the basis of information input from the external sensor ES. For example, a position of an object is recognized as a position in an absolute coordinate system with an origin set to a representative point of the vehicle M (such as the center of gravity or the center of a drive shaft) and is used for control. A position of an object may be expressed as a representative point such as the center of gravity or a corner of the object or may be expressed as an area. A “state” of an object may include an acceleration or a jerk of the object or a “moving state” (for example, whether lane change is being performed or whether lane change is going to be performed) thereof.

The recognizer130recognizes, for example, a lane (a traveling lane) in which the vehicle M is traveling. For example, the recognizer130recognizes right and left lane markings of the vehicle M from a camera image captured by the camera10and recognizes the traveling lane on the basis of positions of the recognized lane markings. The recognizer130is not limited to the lane markings, but may recognize the traveling lane by recognizing objects capable of identifying a lane position (such as traveling lane boundaries or road boundaries) including edges of roadsides, curbstones, median strips, guard rails, fences, walls, and the like. In this recognition, the position of the vehicle M acquired from the navigation device50and the result of processing from the INS may be considered. The recognizer130may recognize a stop line, an obstacle, a red signal, a toll gate, or other road events.

The recognizer130recognizes a position or a direction of the vehicle M with respect to a traveling lane at the time of recognition of the traveling lane. The recognizer130may recognize, for example, a separation of a reference point of the vehicle M from the lane center and an angle of the traveling direction of the vehicle M with respect to a line formed by connecting the lane centers as the position and the direction of the vehicle M with respect to the traveling lane. Instead, the recognizer130may recognize a position of a reference point of the vehicle M with respect to one side line of the traveling lane (a lane marking or a road boundary) or the like as the position of the vehicle M with respect to the traveling lane. Recognition of the traveling lane in the recognizer130or recognition of the position or posture of the vehicle M with respect to the traveling lane may be performed by an identifier153which will be described later.

The movement plan creator140creates a target trajectory in which the vehicle M will travel autonomously (without requiring a driver's operation) in the future such that the vehicle M can travel in a recommended lane determined by the recommended lane determiner61in principle and cope with a surrounding situation of the vehicle M. A target trajectory includes, for example, a speed element. For example, a target trajectory is expressed by sequentially arranging points (trajectory points) at which the vehicle M is to arrive. Trajectory points are points at which the vehicle M is to arrive at intervals of a predetermined traveling distance (for example, about several [m]) along a road, and a target speed and a target acceleration at intervals of a predetermined sampling time (for example, below the decimal point [sec]) are created as a part of the target trajectory in addition. Trajectory points may be positions at which the vehicle M is to arrive at sampling times every predetermined sampling time. In this case, information of a target speed or a target acceleration is expressed by intervals between the trajectory points.

The movement plan creator140may set events (functions) of automated driving in creating a target trajectory. The events of automated driving include a constant-speed travel event, a low-speed following travel event, a lane change event, a branching event, a merging event, and an overtaking event. The movement plan creator140creates a target trajectory based on an event which is started.

The mode determiner150determines one of a plurality of driving modes with different tasks to be imposed on a driver (in other words, a plurality of modes with different automation levels) as a driving mode of the vehicle M. The mode determiner150includes, for example, a driver state determiner151, a first acquirer152, an identifier153, and a mode change processor154. These individual functions will be described later. The first acquirer152is an example of an “acquirer.”

FIG.3is a diagram illustrating an example of correspondence between driving modes and control states of the vehicle M and tasks. In the example illustrated inFIG.3, examples of a driving mode of the vehicle M include five modes including modes A to E. InFIG.3, it is assumed that modes A and B are an example of a “first driving mode,” and modes C, D, and E are an example of a “second driving mode.” The driving mode may include a mode other than modes A to E, or may include a driving mode other than the first driving mode and the second driving mode. In modes A to E, a control state, that is, an automation level (a degree of control) of driving control of the vehicle M, is the highest in mode A, decreases in the order of mode B, mode C, and mode D, and is the lowest in mode E. On the other hand, tasks to be imposed on a driver (an occupant) are the lightest in mode A, become heavier in the order of mode B, mode C, and mode D, and are the heaviest in mode E in which manual driving is performed. In mode B to E, since the control state is not automated driving, the automated driving control device100has to end control associated with automated driving and take charge of transitioning to driving support or manual driving. Details of the driving modes will be exemplified below.

In mode A, the control state is an automated driving state and none of surrounding monitoring of the vehicle M and grasping of the steering wheel82(hereinafter referred to as steering wheel grasp) is imposed on a driver. The surrounding monitoring includes at least monitoring in the traveling direction (for example, forward monitoring) of the vehicle M. Forward monitoring means monitoring a space in the traveling direction of the vehicle M which is seen through a front windshield. Even in mode A, the driver is requested to take a posture that can rapidly transition to manual driving in response to a request from a system centered on the automated driving control device100. Automated driving mentioned herein means that both steering and speed of the vehicle M are controlled without requiring a driver's operation. For example, mode A is a driving mode which is executable when conditions that the vehicle M is traveling at a predetermined speed (for example, about50[km/h]) or lower on a motorway such as a highway and a preceding vehicle to be followed is present are satisfied, and is also referred to as traffic jam pilot (TJP). When the conditions are not satisfied, the mode determiner150changes the driving mode of the vehicle M to mode B.

When mode A is being executed, an occupant can perform a second task. The second task is, for example, an action of the occupant which is permitted when the vehicle M is performing automated driving other than driving of the occupant. For example, the second task includes watching of a television program, use (for example, calling, mail transmission/reception, use of a social networking service (SNS), or web browsing) of a terminal device (for example, a smartphone or a tablet terminal) which is carried by the occupant, or eating of a meal.

In mode B, the control state is a driving support state, a task for monitoring the surroundings of the vehicle M (hereinafter referred to as surrounding monitoring) is imposed on a driver, and a task for grasping the steering wheel82is not imposed on the driver. For example, in mode B, a lane change instruction from an occupant is not received and lane change of the vehicle M based on settings of a route to a destination in the navigation device50or the like is performed on the basis of a determination result from the vehicle system1side. Lane change is to move the vehicle M from a traveling lane on which the vehicle M is traveling to a neighboring lane adjacent to the traveling lane and may include lane change based on branching or merging. A driving identity in modes A and B is the vehicle system1.

In mode C, the control state is a driving support state, and the task for monitoring the surroundings and the task for grasping the steering wheel82are imposed on a driver. For example, in mode C, when the vehicle system1determines that lane change of the vehicle M is necessary, an occupant is inquired of via the HMI30, and driving support for performing lane change is performed when an approval for lane change from the occupant is received via the HMI30or the like. Lane change control in modes B and C is performed by a system identity.

Mode D is a driving mode in which a driver's driving operation to a certain extent is required for at least one of steering and acceleration/deceleration of the vehicle

M. For example, in mode D, driving support such as adaptive cruise control (ACC) or lane keeping assist system (LKAS) is performed. In mode D, when an instruction to perform lane change of the vehicle M is received through a driver's operation of the direction indicator switch32, driving support for performing lane change in an instructed direction is performed. The lane change in mode D is lane change according to a driver's intention. The driver's operation of the direction indicator switch32is an example of a driving operation. The driving operation in mode D may include a driving operation for controlling steering or acceleration/deceleration.

In mode E, the control state is a manual driving state in which a driver's driving operation is required for both steering and acceleration/deceleration of the vehicle M. In modes D and mode E, the task for monitoring the surroundings of the vehicle M is imposed on a driver. The driving identity in modes C to E is a driver.

The mode determiner150changes the driving mode of the vehicle M to a driving mode with heavier tasks when a task associated with the determined driving mode is not performed by a driver.

For example, in mode A, when a driver takes a posture with which the driver cannot transition to manual driving in response to a request from a system (for example, when the driver is looking outside of a permitted area or when a sign for making driving difficult is detected), the mode determiner150causes the HMI controller170to perform control such that the driver is prompted to transition to manual driving in mode E using the HMI30. The mode determiner150performs control such that the vehicle M is put on a target position (for example, a road edge) and slowly stopped and automated driving is stopped when the driver does not respond within a predetermined time after the HMI controller170has been caused to perform control for prompting the driver to transition to manual driving or when it is estimated that the driver has not taken a posture for manual driving. After automated driving has been stopped, the vehicle M is in mode D or E, and thus the vehicle M can be started by the driver's manual operation. This is the same for “stopping of automated driving.”

When a driver is not monitoring a space in front of the vehicle in mode B, the mode determiner150prompts the driver to perform forward monitoring using the HMI30and performs control such that the vehicle M is put on a target position and slowly stopped and automated driving is stopped when the driver does not respond. In mode C, when a driver does not perform forward monitoring or when the driver does not grasp the steering wheel82, the mode determiner150prompts the driver to perform forward monitoring and/or grasping of the steering wheel82using the HMI30and performs control such that the vehicle M is put on a target position and slowly stopped and automated driving is stopped when the driver does not respond.

The driver state determiner151determines whether an occupant (a driver) is suitable for driving. For example, the driver state determiner151monitors a driver's state for the mode change and determines whether the driver's state is a state corresponding to a task. For example, the driver state determiner151performs a posture estimating process by analyzing an image captured by the driver monitoring camera70and determines whether the driver takes a posture with which the driver cannot transition to manual driving in response to a request from the system. The driver state determiner151performs a gaze estimating process by analyzing an image captured by the driver monitoring camera70and determines whether the driver is monitoring the surroundings of the vehicle M (more specifically, a space in front of the vehicle). When it is determined that the driver is not in the state corresponding to the task for a predetermined time or more, the driver state determiner151determines that the driver is not suitable for driving corresponding to the task. When it is determined that the driver is in the state corresponding to the task, the driver state determiner151determines that the driver is suitable for driving corresponding to the task. The driver state determiner151may determine whether an occupant is in a state in which driver turnover is possible.

The first acquirer152acquires the first map information54. The first acquirer152acquires reference information for identifying the position of the vehicle M. The reference information is, for example, position information of the vehicle M detected by the vehicle sensor40or a camera image captured by the camera10. The reference information may include some or all of recognition results from the recognizer130.

The identifier153identifiers the traveling lane of the vehicle M out of one or more lanes included in a road on which the vehicle M is traveling with reference to the first map information54on the basis of the position information of the vehicle M included in the reference information. For example, the identifier153sets a traveling lane (a reference lane) of the vehicle M (hereinafter referred to as “reference lane setting” according to necessity) at a predetermined timing, or detects the traveling lane of the vehicle M on the basis of change in behavior of the vehicle M (for example, lane change) after the reference lane has been set or change in a road shape (for example, an increase or decrease in the number of lanes) including the traveling lane and corrects the traveling lane (hereinafter also referred to as “lane tracking” according to necessity). The predetermined timing may be, for example, a predetermined cycle or a timing at which execution of automated driving is started, a timing at which traveling on a predetermined road such as a highway is started, or a timing at which a road section is switched in the first map information54. The predetermined timing may be, for example, a timing at which a current traveling lane is reset and identification of a traveling lane is required again, a timing at which the traveling lane of the vehicle M is not identified and a road does not change within a predetermined distance, or a timing at which an operation of starting automated driving is performed by an occupant. Details of the function of the identifier153will be described later.

The mode change processor154determines a driving mode of the vehicle M on the basis of determination results from the driver state determiner151or identification results from the identifier153, or the like. The mode change processor154may determine that a driving mode which is being executed will be maintained or that the driving mode will be switched to another mode. The mode change processor154performs various processes for change to the driving mode determined by the mode determiner150. For example, the mode change processor154instructs a driving support device (not illustrated) to operate, outputs information for prompting a driver to act from the HMI controller170to the HMI30, or instructs the movement plan creator140to create a target trajectory corresponding to a driving mode.

The second controller160controls the travel driving force output device200, the brake device210, and the steering device220such that the vehicle M travels along the target trajectory created by the movement plan creator140as scheduled.

The second controller160includes, for example, a second acquirer162, a speed controller164, and a steering controller166. The second acquirer162acquires information of the target trajectory (trajectory points) created by the movement plan creator140and stores the acquired information in a memory (not illustrated). The speed controller164controls the travel driving force output device200or the brake device210on the basis of a speed element accessory to the target trajectory stored in the memory. The steering controller166controls the steering device220on the basis of a curved state of the target trajectory stored in the memory. The processes of the speed controller164and the steering controller166are realized, for example, in combination of feed-forward control and feedback control. For example, the steering controller166performs control in combination of feed-forward control based on a curvature of a road in front of the vehicle M and feedback control based on a separation from the target trajectory.

The HMI controller170notifies an occupant of predetermined information using the HMI30. The predetermined information includes, for example, information associated with traveling of the vehicle M such as information on the state of the vehicle M or information on driving control. The information on the state of the vehicle M includes, for example, a speed, an engine rotation speed, and a shift position of the vehicle M. The information on driving control includes, for example, an inquiry about whether lane change is to be performed, information indicating what driving mode is to be executed, information on change of a driving mode, information of a task imposed on an occupant (task request information for an occupant) required for switching the driving mode, and information on a situation of driving control (for example, details of an event which is being performed). The predetermined information may include information not associated with traveling control of the vehicle M such as television programs and contents (for example, movies) stored in a storage medium such as a DVD. The predetermined information may include, for example, a current position or a destination of the vehicle M, information on an amount of fuel remaining, information indicating whether a traveling lane of the vehicle M has been identified, a residual distance until the driving mode is switched, an increasing/decreasing direction in the number of lanes, the number of increased/decreased lanes, and the number of lanes parallel to the traveling lane (the number of parallel lanes).

For example, the HMI controller170may generate an image including the predetermined information and display the generated image on a display device of the HMI30, or may generate vocal sound indicating the predetermined information and output the generated vocal sound from a speaker of the HMI30. The HMI controller170may output the information received by the HMI30to the communication device20, the navigation device50, the first controller120, and the like.

The travel driving force output device200outputs a travel driving force (a torque) for allowing the vehicle to travel to driving wheels. The travel driving force output device200includes, for example, a combination of an internal combustion engine, an electric motor, and a transmission and an electronic control unit (ECU) that controls them. The ECU controls the elements on the basis of information input from the second controller160or information input from the driving operator80.

The brake device210includes, for example, a brake caliper, a cylinder that transmits a hydraulic pressure to the brake caliper, an electric motor that generates a hydraulic pressure in the cylinder, and a brake ECU. The brake ECU controls the electric motor on the basis of the information input from the second controller160or the information input from the driving operator80such that a brake torque based on a braking operation is output to vehicle wheels. The brake device210may include a mechanism for transmitting a hydraulic pressure generated by an operation of a brake pedal included in the driving operator80to the cylinder via a master cylinder as a backup. The brake device210is not limited to the above-mentioned configuration, and may be an electronically controlled hydraulic brake device that controls an actuator on the basis of information input from the second controller160such that the hydraulic pressure of the master cylinder is transmitted to the cylinder.

The steering device220includes, for example, a steering ECU and an electric motor. The electric motor changes a direction of turning wheels, for example, by applying a force to a rack-and-pinion mechanism. The steering ECU drives the electric motor on the basis of the information input from the second controller160or the information input from the driving operator80to change the direction of the turning wheels.

Function of Identifier and Details of Driving Control

Details of the function of the identifier153and details of driving control based on processes of the identifier153will be described below. In the following description, it is assumed that the driver state determiner151determines that a driver appropriately performs a task which is imposed on the driver according to the driving mode and the driving mode is determined on the basis of process details of the identifier153. When the driver state determiner151determines that the driver is not performing a task imposed thereon according to the driving mode, the mode determiner150determines change to a mode corresponding to a task which is being performed by the driver or determines that control for stopping automated driving is performed.

The identifier153identifies the traveling lane of the vehicle M, for example, on the basis of type information of lane markings acquired from an image captured by the camera10(the first camera or one or both of the first camera and the second camera when the second camera is provided) or information of an object capable of identifying a lane position.FIG.4is a diagram illustrating a functional configuration of the identifier153. The identifier153includes, for example, a reference lane setter153A, a lane tracker153B, a reset determiner153C, and an output adjuster153D.

FIG.5is a diagram illustrating identification of a traveling lane on the basis of a traveling situation of the vehicle M. InFIG.5, an example in which the vehicle M is traveling at a speed VM on a road R1is illustrated. In the example illustrated inFIG.5, it is assumed that time t1is the earliest, times t2, t3, t4, and t5are increasingly later in this order, and a position and a speed of the vehicle M at time t* are represented by M(t*) and VM(t*). The road R1includes predetermined road sections (for example, sections A to C) in an extending direction thereof. The road R1(sections A to C) is, for example, a highway. Each section may be separated, for example, by points of change in a road shape (for example, points at which a branching road, a merging road, a curved road, or a tunnel is present) or may be divided for each predetermined length. Section B inFIG.5is a section in which the number of lanes is one less than the number of lanes in section A, and section C is a section in which the number of lanes is one less than the number of lanes in section B. Lanes L1to L6in section A, lanes L2to L6in section B, and lanes L3to L6in section C are lanes extending in the X-axis direction inFIG.5. InFIG.5, an object OB1such as a guard rail which is provided in the extending direction of the lanes is illustrated.

In the first map information54, node information, link information, and information on the number of lanes are stored for each of sections A to C as illustrated inFIG.5. The information on the number of lanes may include an increasing/decreasing direction of the number of lanes, and the number of increased/decreased lanes. For example, the first acquirer152acquires a start point, an end point, and a road shape of section A as nodes NAs and NAe and link RA from the first map information54and acquires information indicating that the number of lanes decreases from six to five and the number of left lanes decreases. Similarly, the first acquirer152acquires road information of section B as nodes NBs and NBe and link RB and acquires information indicating that the number of lanes decreases from five to four and the number of left lanes decreases. The first acquirer152acquires road information of section C as nodes NCs and NCe and link RC and acquires information indicating that the number of lanes is four. In the example illustrated inFIG.5, section A represents a merging section, and the first driving mode is started at a timing (time t2in the drawing) at which the vehicle M merges from a merging road (a merging lane) L1to a main lane (lane L2) which is a merged lane. The merged lane is, for example, a lane parallel to the merging road. Identification of a traveling lane based on traveling situations of the vehicle M at times tl to t5inFIG.5will be described below using the constituents of the identifier153illustrated inFIG.4.

Times t1to t2

Times t1to t2indicate positions of the vehicle M in which the vehicle performs lane change from a position of a branching lane L1(time tl) to a main lane (lane L2) and enters section B at a time point (time t2). At time t2at which the vehicle merges to the main lane L2, the reference lane setter153A sets a traveling lane of the vehicle M at a time point at which the vehicle M starts the first driving mode as a reference lane on the basis of line type information of markings of lanes L2to L6based on a camera image captured by the camera10and recognized by the recognizer130and information of an object capable of identifying a position of a lane.

Specifically, first, the recognizer130recognizes lane markings or an object capable of identifying lane positions on an image plane by analyzing an image (a camera image) of the road R1on which the vehicle M is traveling and which is captured by the camera10, extracting edge points with a large difference in luminance from neighboring pixels in the image, and arranging the extracted edge points. The recognizer130may perform extraction of a feature quantity or extraction of image information through an image emphasizing process, or the like on the image and recognize the lane markings or the object through a matching process with reference to the extracted image information, a predefined pattern matching model, and the like. The recognizer130recognizes type information such as a type (a solid line or a dotted line) or a color for each lane marking on the basis of the result of image analysis. The recognizer130may recognize a type of an object. The recognizer130may recognize a positional relationship between the recognized lane markings or objects or a positional relationship (a relative position) between the lane markings or the objects and the vehicle M. At time t2illustrated inFIG.5, the recognizer130recognizes types or position information of solid lines RL1and RL6, dotted lines RL3to RL5, and an object OB1. The result of recognition from the recognizer130may be acquired as a part of reference information by the first acquirer152.

Then, the reference lane setter153A sets a traveling lane of the vehicle M out of one or more lanes included in the road on which the vehicle M travels as a reference lane on the basis of the reference information acquired by the first acquirer152. Setting of the reference lane is to identify the traveling lane. For example, the reference lane setter153A determines whether the vehicle M is traveling in one lane (lane L2or lane L6) of right and left end lanes of the road RE For example, the reference lane setter153A determines that the vehicle M is traveling in the left end lane (lane L2) of the road R1when a lane marking for defining the left end of the traveling lane of the vehicle M is a solid line, and determines that the vehicle M is traveling in the right end lane (lane L6) of the road R1when a lane marking for defining the right end of the traveling lane is a solid line. When lane markings on the right and left sides of the traveling lane of the vehicle M are dotted lines (the lane marking on one of the right and left sides is not a solid line), the reference lane setter153A determines that the vehicle M is not traveling in the right and left end lanes. The reference lane setter153A may determine whether the vehicle M is traveling in the right and left end lanes on the basis of an object such as a guard rail (an object capable of identifying a lane position) instead of (or in addition to) a solid line. For example, when the left lane marking of the traveling lane of the vehicle M is a solid line and an object OB1is present in a place which is farther from the vehicle M than the lane marking and which is within a predetermined distance from the lane marking, the reference lane setter153A determines that another lane marking is not present near the lane marking and determines that the vehicle M is traveling in the left end lane of the road. Then, the reference lane setter153A sets the determined traveling lane as the reference lane. For example, when execution of automated driving is started, there is a high likelihood that the vehicle is traveling in an end lane out of a plurality of lanes included in the road, and an end lane of the road can be more accurately recognized than a lane other than the end lane. Accordingly, by determining whether the vehicle is traveling in the end lane as the reference lane, it is possible to more accurately set the reference lane.

When it is determined that the vehicle M is not traveling in the right and left end lanes, the reference lane setter153A may set the reference lane on the basis of a combination of a position and a type of a lane marking recognized from a camera image and a current position of the vehicle M. For example, when the number of lane markings recognized on the left side of the vehicle M is two and the line types from the leftmost sequentially include a solid line and a dotted line as the result of analysis of the camera image, the reference lane setter153A determines that the vehicle M is traveling in a second lane from the left end lane of the road. When the number of lane markings recognized on the right side of the vehicle M is four and the line types sequentially include a solid line, a dotted line, a dotted line, and a dotted line, the reference lane setter153A may determine that the vehicle M is traveling in a fourth lane from the right end lane of the road.

When a state in which the traveling lane of the vehicle M has been determined is maintained for a predetermined time or more, the reference lane setter153A may set the determined lane as the reference lane of the vehicle M. Accordingly, it is possible to curb erroneous setting of the reference lane. It is possible to curb frequent switching of the position of the traveling lane due to erroneous determination of a lane marking or the like.

In the example illustrated inFIG.5, at time t2, the reference lane setter153A sets the left end lane L2(the first lane from the left end) of the road R1at a time point at which the vehicle M enters section B as the reference lane. Since the number of lanes of the road on which the vehicle M is traveling can be ascertained from the first map information54, the reference lane setter153A may set the fifth lane from the right end of the road as the reference lane. The reference lane setter153A may set lane numbers (for example, 1 to 5) of the lanes L2to L6and manage the reference lane using the set lane numbers. A lane number is, for example, a number corresponding to lane from the left end or the right end lane of the road. In this case, at time t2, the reference lane is set to a left reference lane number (a lane number with respect to the left end lane)1or a right reference lane number (a lane number with respect to the right end lane)5. After the reference lane of the vehicle M has been set by the reference lane setter153A, the lane tracker153B performs correction based on detection (tracking) of the traveling lane with respect to the reference lane on the basis of behavior of the vehicle M or an increase/decrease (merging or branching) of the number of lanes of the road. Behavior of the vehicle M is, for example, lane change of the vehicle M. The behavior of the vehicle M may include, for example, a state in which lane change is not being performed (for example, a lane kept state by LKAS).

Time t3

Time t3represents a position of the vehicle M after the vehicle M has performed lane change from lane L2to lane L3. In this case, the lane tracker153B determines that the vehicle M is traveling in lane L3on the basis of type information of a lane marking based on the result of analysis of a camera image and a direction and a frequency of lane change. For example, the lane tracker153B performs correction of the position (lane number) of the traveling lane of the vehicle M based on a previous lane number (the lane number of the reference lane herein) with reference to the lane change correction table182stored in the storage180on the basis of a line type (for example, a dotted line) of a lane marking between the traveling lane (reference lane) set by the reference lane setter153A and a neighboring lane, a moving direction at the time of lane change, and a result of determination indicating whether the lane change has been completed.

FIG.6is a diagram illustrating an example of details of the lane change correction table182. In the lane change correction table182, for example, detection (correction) details of the traveling lane with respect to the left reference lane number and the right reference lane number are correlated with behavior of the vehicle M. For example, when driving support of LKAS is performed after the reference lane has been set by the reference lane setter153A, lane change of the vehicle M has not been performed and thus the lane tracker153B maintains the previous lane number. When the vehicle M is performing lane change from the current lane to a left neighboring lane (when left LC is being performed) or when the vehicle M is performing lane change from the current lane to a right neighboring lane (when right LC is being performed), lane change has not been completed and thus the lane tracker153B maintains the previous lane number. When the traveling lane has been identified with respect to the left end of the road, the lane tracker153B acquires a value obtained by subtracting 1 from the previous lane number as a new lane number of the traveling lane when lane change to the left neighboring lane has been completed, and acquires a value obtained by adding 1 to the previous lane number as a new lane number of the traveling lane when lane change to the right neighboring lane has been completed. When the traveling lane has been identified with respect to the right end of the road, the lane tracker153B acquires a value obtained by adding 1 to the previous lane number as a new lane number of the traveling lane when lane change to the left neighboring lane has been completed, and acquires a value obtained by subtracting 1 from the previous lane number as a new lane number of the traveling lane when lane change to the right neighboring lane has been completed. “Lane change has been completed” means, for example, a case in which a traveling locus of the vehicle M (for example, a locus extending to the rear of the vehicle M using position information of the vehicle M acquired from the vehicle sensor40) goes over a lane marking for defining the current traveling lane and a neighboring lane which is a lane change destination. “Lane change has been completed” means, for example, a case in which a reference position (for example, the center of gravity) of the vehicle M goes over a lane marking for defining the current traveling lane and a neighboring lane which is a lane change destination or a case in which the whole vehicle M or all wheels of the vehicle M are present in the neighboring lane which is a lane change destination. When behavior of the vehicle cannot be identified (when whether lane change has been completed cannot be recognized), the lane tracker153B may acquire a lane number (for example, 0) indicating that a lane is undetermined (not tracked). At time t3, since lane change from the traveling lane L2identified by the reference lane setter153A to the right lane L3has been completed, the traveling lane is identified as the left reference lane number2or the right reference lane number4.

Time t4

Time t4represents a position of the vehicle M after the vehicle M has performed lane change from lane L3to lane L4which is farther to the right side. In this case, the lane tracker153B detects a current traveling lane (lane number) based on the previous lane number (the lane number corrected through tracking at time t3herein) with reference to the lane change correction table182stored in the storage180on the basis of a line type of a lane marking (for example a dotted line) between the current traveling lane L3and the neighboring lane L4, a moving direction when lane change is performed, and the result of determination indicating whether lane change has been completed.

In a period from time t2to time t4, the lane tracker153B may adjust an increasing/decreasing number from the reference lane number on the basis of the frequency of lane change in the same direction. For example, when lane change to the right side has been performed two times (when lane change to the left side has not been performed), the lane tracker153B acquires a value which is obtained by adding2to the previous lane number when lane change with respect to the left side has been performed or obtained by subtracting2from the previous lane number when lane change with respect to the right side has been performed as a new reference lane number. At time t4, since lane change from the traveling lane L3identified (corrected) through the previous lane tracking to the right lane L4has been completed, the traveling lane is identified as the left reference lane number3or the right reference lane number3.

For example, when a part of a lane marking near the vehicle M is hidden behind another nearby vehicle or cannot be recognized due to wearing of the lane marking or a surrounding environment such as weather in recognition of a surrounding situation in the recognizer130, the lane tracker153B may linearly interpolate the non-recognized part of the lane marking using a locus of the lane marking which has been previously recognized. Accordingly, even when a lane marking is not temporarily recognized, it is possible to identify the traveling lane and to maintain the first driving mode. When a lane marking cannot be recognized for a predetermined time or more, the interpolating process may not be performed to avoid continuation of interpolation more than required and it may be determined that the traveling lane is undetermined.

Time t5

When the number of lanes of the road including the traveling lane increases or decreases on the basis of the result of analysis of a camera image captured by the camera10or the first map information54, the lane tracker153B corrects the traveling lane of the vehicle M according to the number of increasing/decreasing lanes. Specifically, when the number of lanes of the road including the traveling lane of the vehicle M increases or decreases, the lane tracker153B determines in which of the right and left lanes in an extending direction of the road increases or decreases.

Time t5indicates a position of the vehicle M when the number of lanes of the road R1including the traveling lane of the vehicle M decreases by one from the left end. In this case, the lane tracker153B corrects the position of the traveling lane based on the number of lanes with reference to the lane increase/decrease correction table184stored in the storage180.

FIG.7is a diagram illustrating an example of details of the lane increase/decrease correction table184. In the lane increase/decrease correction table184, for example, detection (correction) details of the traveling lane with respect to the left reference lane number and the right reference lane number are correlated with increase/decrease details of the number of lanes included in the road on which the vehicle M is traveling.

For example, in section B, when the number of lanes decreases from five lanes (lanes L2to L6) to four lanes (lanes L3to L6), one lane at the left end is reduced. Accordingly, when it is determined on the basis of a camera image or information acquired from the first map information54that one lane on the left side decreases, the lane tracker153B corrects the traveling lane of the vehicle M on the basis of lane detection details of the traveling lane in which increase/decrease details correspond to “left decrease” with reference to the lane increase/decrease correction table184. For example, when the lane numbers are based on the left end, the lane tracker153B corrects the lane number from the lane number2by subtracting the number of decreasing lane1from the previous lane number (the right reference lane number3). When the lane numbers are based on the right end, the lane tracker153B maintains the previous lane number (the right reference lane number3) (without performing correction).

In this way, it is possible to more accurately identify the traveling lane of the vehicle M on the basis of information indicating whether lane change of the vehicle M has been performed, an increase/decrease in the number of lanes of the traveling road, or the like. Accordingly, it is possible to execute the first driving mode on the basis of the identified traveling lane and to change a control level of the driving control in a more appropriate situation when there is branching or the like.

The lane tracker153B may perform tracking of the traveling lane based on behavior of the vehicle M or an increase/decrease in the number of lanes of a road and setting of the traveling lane based on the result of analysis of a camera image in the reference lane setter153A, compare the results thereof, and correct the traveling lane when both the traveling lanes match.

The lane tracker153B may reset information of the identified current traveling lane of the vehicle M on the basis of the result of determination from the reset determiner153C. For example, when the number of lanes of the road on which the vehicle M is traveling based on the result of analysis of a camera image is different from the number of lanes of the road on which the vehicle M is traveling and which is acquired from the first map information54on the basis of the position information of the vehicle M, the reset determiner153C determines that the position information (the lane number) of the current traveling lane is to be reset. When the traveling lane set on the basis of the result of analysis of a camera image by the reference lane setter153A is different from the traveling lane identified on the basis of the behavior of the vehicle tracked by the lane tracker153B or the increase/decrease in the number of lanes, the reset determiner153C determines that the position information (lane number) of the current traveling lane is to be reset.

FIG.8is a diagram illustrating identification of a traveling lane based on behavior of a vehicle.FIG.9is a diagram illustrating identification of a traveling lane based on a camera image. In the examples illustrated inFIGS.8and9, it is assumed that the vehicle M travels on a lane L12at a speed VM in a section (for example, a merging section) PO1in which three lanes (lanes L11to L13) decreases to two lanes (lanes L12and L13). The lane L11is an example of a merging road. The lane L12is an example of a merged lane. In the examples ofFIGS.8and9, it is assumed that the lane L11is defined by a solid line RL11on the left side and a road structure (for example, a curbstone) OB2and a dotted line RL12on the right side, the lane L12is defined by a road structure OB2and a dotted line RL12on the right side and a dotted line RL13on the left side, and the lane L13is defined by a dotted line RL13on the left side and a solid line RL14on the right side. InFIGS.8and9, time tll is the earliest, and t12and t13are later in this order.

In the example illustrated inFIG.8, the lane tracker153B recognizes that the vehicle M is traveling on the left end lane L12of the road on the basis of the line types of the right and left lane markings at time t11. When a traveling lane is tracked on the basis of whether lane change is performed, lane change is not performed in a period from time t11to time t13(a period in which the vehicle passes through the section PO1) and thus the lane tracker153B determines that the vehicle is continuously traveling on the left end lane. On the other hand, when the traveling lane of the vehicle M is identified on the basis of the result of analysis of a camera image at time t12illustrated inFIG.9, the lane tracker153B recognizes that the vehicle is traveling on the second lane from the left end on the basis of the sold line of the lane marking RL11and the dotted line of the lane marking RL12, and thus the traveling lanes do not match when management based on the left reference lane numbers is performed. This state can occur in a section in which the number of lanes increases or decreases such as a merging section or a branching section.

Accordingly, when the positions of the traveling lanes do not match as described above, the reset determiner153C determines that the position information of the current traveling lane is to be reset. When it is determined that the position information of the traveling lane is to be reset by the reset determiner153C, the lane tracker153B outputs a reset request to the output adjuster153D. The lane tracker153B may output a reset flag indicating whether the position information of the traveling lane is to be reset to the output adjuster153D.

The output adjuster153D performs a process of adjusting the traveling lane of the vehicle M on the basis of the reset flag or the reset request. For example, the output adjuster153D performs output adjustment of the lane number on the basis of behavior of the vehicle M or an increase or decrease in the number of lanes (merging or branching).FIG.10is a flowchart illustrating an example of a routine of processes which is performed by the output adjuster153D. In the example illustrated inFIG.10, the output adjuster153D determines whether a previous lane has been identified (Step S100). The previous lane is a traveling lane which is identified through previous lane tracking out of lane tracking which is performed at a predetermined timing. The previous lane may be a traveling lane which is set through setting of a reference lane. When the previous lane has been identified, the output adjuster153D determines whether a reset request has been issued from the reset determiner153C (Step S102).

When it is determined that a reset request has been issued, the output adjuster153D determines whether a section in front of the vehicle M having issued the reset request is a branching or merging section (Step S104). In the process of Step S104, the output adjuster153D determines whether a section in front of the vehicle M is a merging or branching section in which the number of lanes increases or decreases temporarily with reference to the first map information54on the basis of the position information of the vehicle M. When it is determined that the front section is a branching or merging section, the output adjuster153D outputs the traveling lane identified through lane tracking (Step S106). When it is determined in Step S102that a reset request has not been issued, the output adjuster153D also performs the process of Step S106.

When it is determined in Step S100that a previous lane has not been identified, the output adjuster153D does not perform lane change or the like and determines whether the current lane is maintained through driving control such as LKAS (Step S108). When it is determined that the current lane is maintained, the output adjuster153D outputs the traveling lane set through reference lane setting (Step S110). When it is determined in Step S104that the front section is not a branching or merging section, the output adjuster153D also performs the process of Step S110.

When it is determined in Step S108that the current lane is not maintained (in other words, lane change is performed), the output adjuster153D outputs information indicating that the traveling lane is undetermined (Step S112). In the process of Step S112, a process of outputting the corresponding information (for example, error information) from the HMI30via the HMI controller170or switching the first driving mode to the second driving mode or the like may be performed. Thereafter, the routine of the flowchart ends. By identifying the traveling lane through an adjustment process as described above, it is possible to more accurately identify the traveling lane and to more appropriately perform driving control using information of the identified traveling lane, for example, when the identified traveling lanes are different as illustrated inFIGS.8and9.

For example, when it is determined in Step S104that the vehicle M is traveling in a merging section or a branching section, the output adjuster153D may identify the traveling lane in additional consideration of lane types (for example, a merged lane, a takeover lane, or a branching lane). For example, when it is determined that the vehicle M is traveling in a merging section, the output adjuster153D may determine whether the vehicle M is traveling on a merged lane.FIG.11is a flowchart illustrating an example of a routine of determining a traveling lane in a merging section. In the example illustrated inFIG.11, the output adjuster153D determines whether the position of the vehicle M is within a predetermined distance from a merging point (Step S200). When it is determined that the position of the vehicle M is within the predetermined distance, the output adjuster153D determines whether a type of the previous traveling lane is a merged lane (Step S202). When it is determined that the type is a merged lane, the output adjuster153D determines whether lane change is performed after the traveling lane has been previously identified (Step S204). When it is determined that lane change has not been performed, the output adjuster153D determines that the traveling lane of the vehicle M is a merged lane and outputs the traveling lane identified through lane tracking (Step S206).

When it is determined in Step S202that the previous lane is not a merged lane, the output adjuster153D determines whether the traveling lane has been identified (Step S208). When it is determined that the traveling lane has been identified, the output adjuster153D determines whether the traveling lane is an end lane in a merging direction (Step S210). When it is determined that the traveling lane is an end lane in the merging direction, the output adjuster153D determines that the traveling lane of the vehicle M is a merged lane and outputs the traveling lane set through reference lane setting (Step S212).

When it is determined in Step S208that the traveling lane has not been identified, the output adjuster153D outputs information indicating that the traveling lane of the vehicle M is a merged lane cannot be determined (Step S214). When it is determined in Step S200that the position of the vehicle M is not within from the predetermined distance from the merging point, when it is determined in Step S204that lane change has been performed, or when it is determined in Step S210that the traveling lane is not an end lane in the merging direction, the output adjuster153D determines that the traveling lane of the vehicle M is not a merged lane (Step S216). Thereafter, the routine of the flowchart ends. In this way, by identifying a traveling lane in a merging section and ascertaining that the vehicle is traveling in a merged lane (a lane parallel to a merging road), it is possible to perform control based on a traveling situation such as putting an inter-vehicle distance or decelerating such that another vehicle can easily enter the merged lane from the merging road without performing lane change to the lane L11in the first driving mode. The routine illustrated inFIG.11can be applied to a branching section. Accordingly, by identifying a traveling lane in a branching section and ascertaining that the vehicle is traveling in a branched lane (a lane parallel to a branching road), it is possible to perform more accurate driving control such as lane change to a lane for traveling to a destination or speed control.

The routine illustrated inFIG.11may be performed when the reference lane setter153A or the lane tracker153B identifies the traveling lane (sets the reference lane) of the vehicle M regardless of whether a reset request has been issued. For example, when it is determined that a section in front of the vehicle M is a merging or branching section with reference to the first map information54on the basis of the position information of the vehicle M, the lane tracker153B identifies a traveling lane in the merging or branching section on the basis of a position of the identified traveling lane (or the set reference lane) whether the vehicle M has performed lane change before the vehicle reaches the section. For example, in the situation illustrated inFIG.8or9, the lane tracker153B identifies the lane L12parallel to the merging road as the traveling lane in the section PO1when the vehicle M is traveling on a merged lane (the left end lane L12) (traveling on the right end lane when the merging road is located on the right side) out of the lanes L12and L13parallel to the merging road (the lane L11). On the other hand, when the vehicle M is traveling in a lane parallel to the merging road and a state in which the vehicle M is determined to be traveling on a lane other than the right and left end lanes on the basis of type information of the lane markings is maintained for a predetermined time or more, the lane tracker153B determines that the traveling lane is not undetermined and performs control for issuing a reset request or executing the second driving mode. The relationship between the merging road and the lane parallel to the merging road may be replaced with a relationship between a branching road and a lane parallel to the branching road. Accordingly, it is possible to more accurately identify the traveling lane in a section in which the number of lanes increases or decreases temporarily such as a merging road or a branching road.

For example, when the traveling lane of the vehicle M is identified, the mode change processor154executes a predetermined driving mode (for example, the first driving mode (mode A or mode B)) on the basis of the identified traveling lane. When the traveling lane of the vehicle M is undetermined (is not identified) (when the traveling lane is undetermined even through the adjustment process), the mode change processor154switches the first driving mode under execution (mode A or mode B) to the second driving mode (mode C, mode D, or mode E).

When the traveling lane of the vehicle M is undetermined, the mode change processor154may cause the vehicle M to travel while maintaining the driving mode under execution (without switching the driving mode). In this way, by maintaining the current driving mode without changing the driving control for the vehicle M, it is possible to realize traveling with priority on stability.

When the first driving mode is being executed and a section in which the traveling lane of the vehicle M is undetermined is within a predetermined distance, the mode change processor154may continue to execute the first driving mode. This is because driving control such as LKAS is possible when the traveling lane of the vehicle M cannot be identified out of one or more lanes included in the road but lane markings of the traveling lane are recognized. In this way, by clearly defining conditions that the first driving mode cannot be maintained, the mode determiner150can change to a safer driving mode in a section in which the conditions are satisfied.

When the driving mode executed by the vehicle M is switched from the first driving mode to the second driving mode, the HMI controller170generates information for prompting an occupant of the vehicle M to perform a task corresponding to the driving mode and outputs the generated information from the HMI30. For example, the HMI controller170generates an image indicating specific details of the task to be performed by the occupant and outputs the generated image to a display device of the HMI30. The HMI controller170may generate vocal sound data correlated with image information and output the generated data from a speaker of the HMI30. The HMI controller170may notify the occupant that switching to the second driving mode is needed by outputting an alarm or the like. Accordingly, it is possible to allow the occupant to understand that the driving mode is switched or that a predetermined task is imposed on the occupant and to prepare for switching the driving mode. When the driving mode executed by the vehicle M is switched from the second driving mode to the first driving mode, the HMI controller170may output the changed driving mode or information indicating that the task imposed on the occupant changes (becomes heavier) to the occupant of the vehicle M from the HMI30.

Process flow

A flow of a routine which is performed by the automated driving control device100according to the embodiment will be described below. In the following description, processes of identifying a traveling lane of a vehicle M and switching a driving mode on the basis of the identified traveling lane out of the processes performed by the automated driving control device100will be mainly described. The routine of the flowchart may be performed, for example, repeatedly at predetermined timings.

FIG.12is a flowchart illustrating an example of a routine of a driving control process which is performed by the automated driving control device100. In the example illustrated inFIG.12, the recognizer130recognizes a surrounding situation of a vehicle M (Step S300). Then, the mode determiner150causes the vehicle to travel in one of a plurality of preset driving modes on the basis of the surrounding situation (Step S302).

Then, the mode determiner150acquires the first map information and reference information for identifying a position of the vehicle M (Step S304) and identifies a traveling lane of the vehicle M on the basis of the acquired information (Step S306). The process of Step S306may include a process of setting a reference lane of the vehicle M. Then, the mode determiner150determines whether the vehicle M is executing the first driving mode (Step S308). When it is determined that the vehicle M is traveling in the first driving mode, the identifier153determines whether the traveling lane of the vehicle M is identified out of one or more lanes included in a road on which the vehicle M is traveling (Step S310). When it is determined that the traveling lane of the vehicle M is not identified (undetermined), the mode change processor154performs control for switching the driving mode of the vehicle M from the first driving mode to the second driving mode (Step S312). Thereafter, the routine of the flowchart ends. When it is determined in Step S308that the vehicle is not traveling in the first driving mode, the routine of the flowchart ends.

FIG.13is a flowchart illustrating an example of a routine of identifying the traveling lane of the vehicle M. The routine illustrated inFIG.13represents details of the process of Step S306. In the routine illustrated inFIG.13, the identifier153sets a reference lane on the basis of a type of lane markings near the vehicle M acquired from a camera image (Step S306A).

Then, the identifier153determines whether lane change has been performed (Step S306B) and corrects the position of the traveling lane on the basis of the direction and the frequency of lane change when it is determined that lane change has been performed (Step S306C). After the process of Step S306C has been performed or when it is determined in Step S306B that lane change has not been performed, the identifier153determines whether the number of lanes of the road including the traveling lane has increased or decreased (Step S306D). When it is determined that the number of lanes has increased or decreased, the identifier153corrects the traveling lane of the vehicle Mon the basis of the increasing/decreasing direction of the number of lanes and the number of increased/decreased lanes (Step S306E).

After the process of Step S306E has been performed or when it is determined in Step S306D that the number of lanes has not increased or decreased, the identifier153performs reset determination of the traveling lane and determines whether reset is necessary (in other words, whether a reset request has been issued) (Step S306F). When it is determined that reset of the traveling lane is necessary, the identifier153adjusts information to be output as the traveling lane (Step S306G) and outputs the result of adjustment (Step S306H). When it is determined in Step S306F that reset of the traveling lane is not necessary, the identifier153outputs the identified traveling lane (which includes the corrected traveling lane) (Step S3061). Thereafter, the routine of the flowchart ends.

Modified Examples

In the aforementioned embodiment, reference lane setting and lane tracking may be performed again instead of performing the adjustment process in response to a reset request for the traveling lane. When the reference lane is set by the reference lane setter153A, the driving controller may perform lane change such that the vehicle M is located on the right end lane or the left end lane of the road on which the vehicle M is traveling. Accordingly, it is possible to more accurately set the reference lane.

In the aforementioned embodiment, when map information (second map information) which is more precise than the first map information54is stored in addition to the first map information54and the second map information cannot be acquired, control for identifying the traveling lane using the first map information54or an image captured by the camera10and maintaining the first driving mode on the basis of the identified information may be performed.

The second map information is, for example, map information in which road information is defined for each lane in a section shorter than in the first map information54. The second map information may include, for example, information of lane centers or information of lane boundaries. The second map information may include road information, traffic regulation information, address information (addresses and post codes), facility information, and phone number information. The second map information may be updated from time to time by allowing the communication device20to communicate with another device. For example, the second map information may be stored in a storage device such as an HDD or a flash memory of the MPU60or may be stored in the storage180.

For example, when the second map information is stored in the MPU60or the storage180, the recommended lane determiner61divides a route on a map provided from the navigation device50into a plurality of blocks and determines a recommended lane for each block with reference to the second map information. In this case, the recommended lane determiner61may determine which lane from the leftmost the vehicle M is to travel using lane information included in the second map information.

For example, when the vehicle M is executing the first driving mode and the second map information cannot be used due to a data abnormality of the second map information, an update abnormality of the second map information, or the like, the mode determiner150identifies the traveling lane of the vehicle M on the basis of the information acquired from the first map information54and maintains the first driving mode as described above. Accordingly, even in a situation in which the second map information cannot be used, it is possible to execute a driving mode with a high automation level.

In the aforementioned embodiment, when the first driving mode is switched to the second driving mode, the mode determiner150may determine to what of a plurality of modes included in the second driving mode the driving mode is to be switched according to a traveling state or a traveling environment of the vehicle M. The traveling state is, for example, a driver state which is determined by the driver state determiner151. The traveling environment is, for example, a road shape near the vehicle M, the number of lanes, whether there is a branching or merging section, the number of nearby vehicles, or the relative positions of the nearby vehicles. For example, when conditions for switching from the first driving mode to the second driving mode are satisfied, the mode determiner150determines switching to mode C when the number of lanes in the case in which the traveling lane of the vehicle M cannot be identified is three, switching to mode D when the number of lanes is four, and switching to mode E when the number of lanes is five or more. Accordingly, it is possible to allow the vehicle M to travel in a more appropriate mode according to the traveling state or the traveling environment.

According to the aforementioned embodiment, the vehicle control device includes the recognizer130configured to recognize a surrounding situation of a vehicle M, the driving controller configured to control one or both of steering and speed of the vehicle M on the basis of the surrounding situation recognized by the recognizer130, the acquirer (the first acquirer152) configured to acquire map information (the first map information54) including lane information near the vehicle M and reference information for identifying a position of the vehicle M, and the identifier153configured to identify a traveling lane of the vehicle out of one or more lanes included in a road on which the vehicle M is traveling from the map information on the basis of the reference information, and the identifier153is configured to set a reference lane on which the vehicle travels on the basis of the number of lanes of the road acquired from the map information and type information of lane markings near the vehicle recognized by the recognizer130or information of an object capable of identifying a lane position and to identify the traveling lane of the vehicle M on the basis of the set reference lane, the behavior of the vehicle M, and an increase or decrease in the number of lanes of the road. Accordingly, it is possible to more accurately identify a traveling lane of a vehicle. As a result, it is possible to maintain the first driving mode using information of an accurate traveling lane or to change a degree of control of driving control in a more appropriate situation.

According to the embodiment, when marking line types and arrangements thereof acquired from camera images conform to a predetermined rule (for example, road standards by country), it is possible to identify in which of a plurality of lanes (parallel lanes) the vehicle is traveling in combination of types. According to the embodiment, it is possible to more accurately correct the traveling lane by detecting an increase/decrease in the number of lanes using information on the number of lanes and an increasing/decreasing direction included in the map information.

According to the embodiment, it is possible to more accurately identify the position (the traveling lane) of the vehicle M and to continuously execute the first driving mode by using the same navigation map (the first map information54) as used in the navigation device50without mounting more precise map information in the vehicle M. Accordingly, since frequent update of map information and management by a map server or the like are not necessary unlike a highly precise map, it is possible to reduce operation costs.

The above-mentioned embodiment can be expressed as follows:

a vehicle control device including:

a storage device that stores a program; and

a hardware processor,

wherein the hardware processor is configured to execute the program to perform:recognizing a surrounding situation of a vehicle;controlling one or both of steering and speed of the vehicle on the basis of the recognized surrounding situation;acquiring map information including lane information near the vehicle and reference information for identifying a position of the vehicle;identifying a traveling lane of the vehicle out of one or more lanes included in a road on which the vehicle is traveling from the map information on the basis of the reference information;setting a reference lane on which the vehicle travels on the basis of the number of lanes of the road acquired from the map information and type information of recognized lane markings near the vehicle or information of an object capable of identifying a lane position; andidentifying the traveling lane of the vehicle on the basis of the set reference lane, behavior of the vehicle, and an increase or decrease in the number of lanes of the road.

The above-mentioned embodiment can also be expressed as follows:

a vehicle control device including:

a storage device that stores a program; and

a hardware processor,

wherein the hardware processor is configured to execute the program to perform:recognizing a surrounding situation of a vehicle;controlling one or both of steering and speed of the vehicle on the basis of the recognized surrounding situation;acquiring map information including lane information near the vehicle and reference information for identifying a position of the vehicle;identifying a traveling lane of the vehicle out of one or more lanes included in a road on which the vehicle is traveling from the map information on the basis of the reference information; andidentifying the traveling lane of the vehicle to be a lane parallel to a merging road or a branching road in a merging or branching section when the merging or branching section is located in front of the vehicle on the basis of the map information, the traveling lane before the vehicle reaches the merging or branching section is one of right and left end lanes included in the road, and it is determined that the vehicle has not performed lane change.

While preferred embodiments of the invention have been described and illustrated above, it should be understood that these are exemplary of the invention and are not to be considered as limiting. Additions, omissions, substitutions, and other modifications can be made without departing from the spirit or scope of the present invention. Accordingly, the invention is not to be considered as being limited by the foregoing description, and is only limited by the scope of the appended claims.