Vehicle controller, vehicle control method, and program

Abstract

To provide a vehicle controller, vehicle control method, and program capable of preferably performing deviation determination when a vehicle goes round a curve.SOLUTION: A vehicle controller includes a recognition unit that recognizes a division line of a road on which an own vehicle travels, a prediction unit that calculates a predictive route of the own vehicle on the basis of a travel condition of the own vehicle, an intersect determination unit that determines whether the division line intersects the predictive route for each predetermined section, and a determination unit that, when it is determined that the predictive route intersects the division line in the predetermined section, calculates a spare time required for the own vehicle to reach an intersection between the predictive route and division line, and that, when the spare time is equal to or smaller than a threshold, determines that it is highly possible that the own vehicle may deviate from the division line.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a vehicle control device, a vehicle control method, and a program. [Background technology]

[0002] In recent years, efforts to provide access to sustainable transportation systems that take into consideration vulnerable traffic participants have been gaining momentum. To achieve this, we are focusing on research and development into preventive safety technologies to further improve traffic safety and convenience. For example, there is currently technology that detects lane departures of moving vehicles (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4534754 Summary of the Invention [Problem to be solved by the invention]

[0004] The conventional technology determines a departure based on the lateral deviation of the vehicle position from the lane center, predicts the direction of departure or the direction to avoid departure based on the yaw angle, and increases the degree of lane keeping control as the tendency to departure increases. In other words, because the conventional technology determines a departure based on the lateral deviation, there is a possibility that delays in control and notification may occur when the vehicle is traveling around a curve.

[0005] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a vehicle control device, a vehicle control method, and a program that can appropriately perform deviation determination when a vehicle is traveling around a curve, thereby contributing to the development of a sustainable transportation system. [Means for solving the problem]

[0006] The vehicle control device according to the present invention employs the following configuration. (1): A vehicle control device according to one embodiment of the present invention is a vehicle control device that includes a recognition unit that recognizes dividing lines on a road on which the vehicle is traveling; a prediction unit that calculates a predicted route for the vehicle based on the traveling state of the vehicle; an intersection determination unit that determines whether the dividing line will intersect with the predicted route for each predetermined section of the dividing line; and a determination unit that, when it is determined that the predicted route will intersect with the dividing line in the predetermined section, calculates the margin of time until the vehicle reaches the intersection between the predicted route and the dividing line, and, when the margin of time is equal to or less than a threshold, determines that there is a high possibility that the vehicle will deviate from the dividing line.

[0007] (2): In the aspect (1) above, when the host vehicle is traveling while making a turning motion, the intersection determination unit calculates the predicted path based on a turning curve based on the current traveling state of the host vehicle.

[0008] (3) In the above aspect (1), when the host vehicle is traveling while making a turning motion, the determination unit calculates the margin time based on a turning curve based on the current traveling state of the host vehicle.

[0009] (4) In the above-mentioned mode (2) or (3), the center of the turning curve is set to the side of the vehicle.

[0010] (5): In the above aspect (4), the center is set in a direction perpendicular to the front direction of the vehicle from an end or ground contact point of the vehicle that is closest to the specified section.

[0011] (6): In another aspect of the present invention, a vehicle control method includes a control device of a vehicle that recognizes dividing lines on a road on which the vehicle is traveling, calculates a predicted route for the vehicle based on the traveling state of the vehicle, determines whether the predicted route will intersect with the dividing line for each predetermined section of the dividing line, calculates a margin of time until the vehicle reaches the intersection of the predicted route and the dividing line if the margin of time is less than a threshold, and determines that there is a high possibility that the vehicle will deviate from the dividing line.

[0012] (7): Another aspect of the present invention is a program that causes a control device of a vehicle to recognize the dividing lines on the road on which the vehicle is traveling, calculate a predicted route for the vehicle based on the traveling state of the vehicle, determine whether the predicted route will intersect with the dividing line for each predetermined section of the dividing line, calculate the margin of time until the vehicle reaches the intersection of the predicted route and the dividing line if it is determined that the predicted route will intersect with the dividing line in the predetermined section, and determine that there is a high possibility that the vehicle will deviate from the dividing line if the margin of time is less than a threshold value. [Effects of the Invention]

[0013] According to the above aspects (1) to (7), it is possible to provide a vehicle control device, a vehicle control method, and a program that can suitably perform departure determination when a vehicle is traveling around a curve.

[0014] More specifically, according to aspects (1), (6), and (7), by calculating the predicted route of the vehicle relative to the road dividing line and determining the intersection, it is possible to suppress delays in control and notification even when there is a possibility of deviation while traveling around a curve. Furthermore, by determining the presence or absence of an intersection (intersection determination) for each predetermined section of the road dividing line, it is possible to reduce the processing load of deviation determination and reduce the possibility of a delay in determination.

[0015] According to the aspect (2), when the host vehicle is traveling while making a turn, the possibility of departure can be appropriately determined even while traveling on a curve by performing an intersection determination using a turning curve (turning curvature) calculated from the current traveling state. Furthermore, by performing an intersection determination using a turning curve, the processing load can be reduced and the possibility of a delay in the determination can be reduced.

[0016] According to the aspect (3), when the vehicle is traveling while making a turn, the possibility of departure can be appropriately determined even while traveling on a curve by performing departure determination based on a turning curve (turning curvature) calculated from the current traveling state. Furthermore, by performing departure determination based on a turning curve, the processing load can be reduced and the possibility of a delay in determination can be reduced.

[0017] Furthermore, in the conventional technology, when determining the turning center (rotation center), the influence of lateral speed errors becomes large when the radius of curvature becomes large, and there is a possibility that the distance of deviation from the lane will be calculated incorrectly. According to the aspect (4), by setting the turning center to the side of the vehicle, it is possible to improve the accuracy of intersection judgment and deviation judgment during turning.

[0018] Furthermore, according to the aspect (5), the accuracy of the departure determination can be improved by performing the departure determination on the parts of the host vehicle that are highly likely to deviate from the lane. [Brief explanation of the drawings]

[0019] [Figure 1] 1 is a configuration diagram of a vehicle system using a vehicle control device according to an embodiment. [Figure 2] FIG. 2 is a functional configuration diagram of a first control unit and a second control unit. [Figure 3] FIG. 2 is a diagram illustrating an example of a correspondence relationship between a driving mode, a control state of a host vehicle, and a task. [Figure 4] 10 is a flowchart showing an example of a basic processing flow in deviation determination. [Figure 5] FIG. 10 is an image diagram for explaining an outline of deviation determination. [Figure 6] 10A and 10B are diagrams illustrating a method for calculating the turning speed and turning center of the host vehicle when traveling around a curve in departure determination. [Figure 7] FIG. 1 is a first diagram illustrating a method for calculating a deviation path length for a vehicle traveling around a curve in a deviation judgment. [Figure 8] FIG. 2 is a second diagram illustrating a method for calculating a deviation path length for the host vehicle when traveling around a curve in deviation judgment. [Figure 9] FIG. 10 is a third diagram illustrating a method for calculating a deviation path length for the host vehicle when traveling around a curve in deviation judgment. DETAILED DESCRIPTION OF THE INVENTION

[0020] Hereinafter, embodiments of a vehicle control device, a vehicle control method, and a program according to the present invention will be described with reference to the drawings.

[0021] [Overall configuration] 1 is a configuration diagram of a vehicle system 1 that uses a vehicle control device according to an embodiment. The vehicle on which the vehicle system 1 is installed may be, for example, a two-wheeled, three-wheeled, or four-wheeled vehicle, and its drive source may be an internal combustion engine such as a diesel engine or a gasoline engine, an electric motor, or a combination of these. The electric motor operates using power generated by a generator connected to the internal combustion engine, or discharged power from a secondary battery or a fuel cell.

[0022] The vehicle system 1 includes, for example, a camera 10, a radar device 12, a LIDAR (Light Detection and Ranging) 14, an object recognition device 16, a communication device 20, an HMI (Human Machine Interface) 30, vehicle sensors 40, a navigation device 50, an MPU (Map Positioning Unit) 60, a driver monitor camera 70, a driving operator 80, an automatic driving control device 100, a driving force output device 200, a braking device 210, and a steering device 220. These devices and equipment are connected to each other via multiplexed communication lines such as a CAN (Controller Area Network) communication line, serial communication lines, a wireless communication network, etc. Note that the configuration shown in FIG. 1 is merely an example, and some of the configuration may be omitted, or other configurations may be added.

[0023] The camera 10 is, for example, a digital camera using a solid-state imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor). The camera 10 is attached to any location of a vehicle (hereinafter referred to as the host vehicle) in which the vehicle system 1 is installed. When capturing an image of the front, the camera 10 is attached to the top of the front windshield, the back of the rearview mirror, or the like. The camera 10, for example, periodically captures images of the surroundings of the host vehicle. The camera 10 may be a stereo camera.

[0024] The radar device 12 emits radio waves such as millimeter waves around the vehicle and detects radio waves reflected by objects (reflected waves) to detect at least the position (distance and direction) of the object. The radar device 12 is attached to any location on the vehicle. The radar device 12 may detect the position and speed of the object using an FM-CW (Frequency Modulated Continuous Wave) method.

[0025] The LIDAR 14 irradiates the surroundings of the vehicle with light (or electromagnetic waves with wavelengths similar to light) and measures the scattered light. The LIDAR 14 detects the distance to the target based on the time between light emission and light reception. The irradiated light is, for example, pulsed laser light. The LIDAR 14 can be attached to any location on the vehicle.

[0026] The object recognition device 16 performs sensor fusion processing on the detection results from some or all of the camera 10, the radar device 12, and the LIDAR 14 to recognize the position, type, speed, etc. of the object. The object recognition device 16 outputs the recognition results to the automatic driving control device 100. The object recognition device 16 may output the detection results from the camera 10, the radar device 12, and the LIDAR 14 directly to the automatic driving control device 100. The object recognition device 16 may be omitted from the vehicle system 1.

[0027] The communication device 20 communicates with other vehicles in the vicinity of the vehicle, or with various server devices via a wireless base station, for example, using a cellular network, a Wi-Fi network, Bluetooth (registered trademark), or DSRC (Dedicated Short Range Communication).

[0028] The HMI 30 presents various information to the occupants of the vehicle and accepts input operations by the occupants. The HMI 30 includes various display devices, speakers, buzzers, touch panels, switches, keys, etc.

[0029] The vehicle sensor 40 includes a vehicle speed sensor that detects the speed of the vehicle, an acceleration sensor that detects acceleration, a yaw rate sensor that detects angular velocity around a vertical axis, and a direction sensor that detects the direction of the vehicle.

[0030] The navigation device 50 includes, for example, a GNSS (Global Navigation Satellite System) receiver 51, a navigation HMI 52, and a route determination unit 53. The navigation device 50 stores first map information 54 in a storage device such as a hard disk drive (HDD) or flash memory. The GNSS receiver 51 determines the position of the vehicle based on signals received from GNSS satellites. The position of the vehicle may be determined or supplemented by an inertial navigation system (INS) that uses the output of the vehicle sensors 40. The navigation HMI 52 includes a display device, a speaker, a touch panel, keys, etc. The navigation HMI 52 may share some or all of the components with the HMI 30 described above. The route determination unit 53 determines, for example, a route (hereinafter, a route on a map) from the position of the vehicle determined by the GNSS receiver 51 (or an arbitrary input position) to a destination input by the occupant using the navigation HMI 52, by referring to the first map information 54. The first map information 54 is information that represents road shapes using, for example, links indicating roads and nodes connected by the links. The first map information 54 may also include information such as road curvature and POI (Point of Interest) information. The route on the map is output to the MPU 60. The navigation device 50 may provide route guidance using the navigation HMI 52 based on the route on the map. The navigation device 50 may be realized, for example, by the functions of a terminal device such as a smartphone or tablet device owned by the occupant. The navigation device 50 may transmit the current position and destination to a navigation server via the communication device 20 and obtain a route equivalent to the route on the map from the navigation server.

[0031] The MPU 60 includes, for example, a recommended lane determination unit 61, and stores second map information 62 in a storage device such as an HDD or flash memory. The recommended lane determination unit 61 divides the route on the map provided by the navigation device 50 into a plurality of blocks (for example, by dividing it into 100 m intervals in the vehicle's travel direction), and determines a recommended lane for each block by referring to the second map information 62. The recommended lane determination unit 61 determines, for example, which lane from the left the vehicle should travel in. When there is a branch point on the route on the map, the recommended lane determination unit 61 determines a recommended lane so that the vehicle can travel on a reasonable route to the branch point.

[0032] The second map information 62 is map information with higher accuracy than the first map information 54. The second map information 62 includes, for example, information on the centers of lanes or information on lane boundaries. The second map information 62 may also include road information, traffic regulation information, address information (address and postal code), facility information, telephone number information, information on prohibited sections where mode A or mode B, described below, is prohibited, and the like. The second map information 62 may be updated as needed by the communication device 20 communicating with another device.

[0033] The driver monitor camera 70 is, for example, a digital camera using a solid-state image sensor such as a CCD or CMOS. The driver monitor camera 70 is attached to any location on the vehicle in a position and orientation that allows it to capture an image of the head of a passenger (hereinafter referred to as the driver) seated in the driver's seat of the vehicle from the front (in an orientation that captures the face). For example, the driver monitor camera 70 is attached to the top of a display device provided in the center of the instrument panel of the vehicle.

[0034] The driving operators 80 include, for example, a steering wheel 82, an accelerator pedal, a brake pedal, a shift lever, and other operators. The driving operators 80 are equipped with sensors that detect the amount of operation or the presence or absence of operation, and the detection results are output to the automatic driving control device 100 or some or all of the driving force output device 200, the brake device 210, and the steering device 220. The steering wheel 82 is an example of an "operator that accepts steering operation by the driver." The operator does not necessarily have to be annular and may be in the form of an irregular steering wheel, a joystick, a button, or the like. A steering grip sensor 84 is attached to the steering wheel 82. The steering grip sensor 84 is realized by a capacitance sensor or the like, and outputs a signal to the automatic driving control device 100 that can detect whether the driver is gripping the steering wheel 82 (meaning that the driver is in contact with the steering wheel in a state where force can be applied).

[0035] The automatic driving control device 100 includes, for example, a first control unit 120, a second control unit 160, and a third control unit 180. The first control unit 120 and the second control unit 160 are each realized by, for example, a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Some or all of these components may be realized by hardware (including circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), a GPU (Graphics Processing Unit), or an SOC (System On Chip), or may be realized by a combination of software and hardware. The program may be stored in advance in a storage device (a storage device having a non-transitory storage medium) such as a HDD or flash memory of the automatic driving control device 100, or may be stored in a removable storage medium such as a DVD or CD-ROM, and installed in the HDD or flash memory of the automatic driving control device 100 by inserting the storage medium (non-transitory storage medium) into a drive device. The automatic driving control device 100 is an example of a "vehicle control device", and the action plan generation unit 140 and the second control unit 160 together are an example of a "driving control unit".

[0036] FIG. 2 is a functional configuration diagram of the first control unit 120 and the second control unit 160. The first control unit 120 includes, for example, a recognition unit 130, an action plan generation unit 140, and a mode determination unit 150. The first control unit 120, for example, implements functions based on AI (Artificial Intelligence) and functions based on a predefined model in parallel. For example, the function of "recognizing intersections" may be implemented by executing intersection recognition using deep learning or the like and recognition based on predefined conditions (such as traffic lights and road signs that can be pattern-matched) in parallel, and then scoring and comprehensively evaluating both. This ensures the reliability of autonomous driving.

[0037] The recognition unit 130 recognizes the position, speed, acceleration, and other states of objects around the vehicle based on information input from the camera 10, the radar device 12, and the LIDAR 14 via the object recognition device 16. The position of an object is recognized as a position on an absolute coordinate system with a representative point of the vehicle (such as the center of gravity or the center of the drive shaft) as the origin, and is used for control. The position of an object may be represented by a representative point such as the center of gravity or a corner of the object, or by an area. The "state" of an object may include the acceleration or jerk of the object, or the "behavioral state" (for example, whether the object is changing lanes or is about to change lanes).

[0038] The recognition unit 130 also recognizes, for example, the lane in which the host vehicle is traveling (driving lane). For example, the recognition unit 130 recognizes the driving lane by comparing the pattern of road dividing lines (e.g., an arrangement of solid and dashed lines) obtained from the second map information 62 with the pattern of road dividing lines around the host vehicle recognized from an image captured by the camera 10. Note that the recognition unit 130 may recognize the driving lane by recognizing road boundaries (road boundaries) including not only road dividing lines but also road dividing lines, shoulders, curbs, medians, guardrails, etc. In this recognition, the position of the host vehicle obtained from the navigation device 50 and the processing results by the INS may be taken into consideration. The recognition unit 130 also recognizes stop lines, obstacles, red lights, toll booths, and other road phenomena.

[0039] When recognizing the driving lane, the recognition unit 130 recognizes the position and orientation of the host vehicle relative to the driving lane. For example, the recognition unit 130 may recognize the deviation of the host vehicle's reference point from the center of the lane and the angle the host vehicle makes with respect to a line connecting the centers of the lanes in the host vehicle's traveling direction as the relative position and orientation of the host vehicle relative to the driving lane. Alternatively, the recognition unit 130 may recognize the position of the host vehicle's reference point relative to either side edge of the driving lane (a road dividing line or a road boundary) as the relative position of the host vehicle relative to the driving lane.

[0040] The behavior plan generation unit 140 automatically (without driver input) generates a target trajectory for the vehicle M to travel in the future so that, in principle, the vehicle M will travel in the recommended lane determined by the recommended lane determination unit 61 and avoid approaching any objects recognized by the recognition unit 130 (excluding objects that can be overcome, such as road dividing lines, road markings, and manholes). For example, the recognition unit 130 sets a risk area centered on the object whose status has been output, and within the risk area, the recognition unit 130 sets a risk as an index value indicating the degree to which the vehicle M should not approach. The behavior plan generation unit 140 generates a target trajectory so that the vehicle M does not pass through points where the risk is equal to or greater than a predetermined value. Because some objects are moving, the risk distribution is not one per control cycle, but is set for multiple future points in time, taking into account the future position of the object predicted based on the object's speed. The target trajectory includes, for example, a speed element. For example, the target trajectory is expressed as a sequential list of points (trajectory points) to be reached by the host vehicle. A trajectory point is a point where the host vehicle should reach at every predetermined travel distance (e.g., about several meters) along the road, and separately, a target speed and a target acceleration are generated for every predetermined sampling time (e.g., about a few tenths of a second) as part of the target trajectory. Alternatively, a trajectory point may be a position where the host vehicle should reach at every predetermined sampling time. In this case, the information on the target speed and target acceleration is expressed as the interval between trajectory points.

[0041] The behavior plan generation unit 140 may set an autonomous driving event when generating the target trajectory. The autonomous driving events include a constant speed driving event, a low-speed following driving event, a lane change event, a branching event, a merging event, a takeover event, etc. The behavior plan generation unit 140 generates a target trajectory according to the activated event.

[0042] The mode determination unit 150 determines the driving mode of the vehicle to be one of a plurality of driving modes that impose different tasks on the driver. The mode determination unit 150 includes, for example, a driver state determination unit 152 and a mode change processing unit 154. The individual functions of these units will be described later.

[0043] FIG. 3 is a diagram showing an example of the correspondence between driving modes, control states of the host vehicle, and tasks. There are five driving modes for the host vehicle, for example, Mode A to Mode E. The control state, i.e., the degree of automation of the host vehicle's driving control, is highest in Mode A, followed by Mode B, Mode C, and Mode D, with Mode E being the lowest. Conversely, the tasks imposed on the driver are lightest in Mode A, followed by Mode B, Mode C, and Mode D, with Mode E being the most severe. Note that Modes D and E are non-autonomous driving control states, and the autonomous driving control device 100 is responsible for terminating control related to autonomous driving and transitioning to driving assistance or manual driving. The following provides examples of the contents of each driving mode.

[0044] In Mode A, the vehicle is in an autonomous driving state, and the driver is not required to monitor the road ahead or grip the steering wheel 82 (in the figure, gripping the steering wheel). However, even in Mode A, the driver is required to be in a position where he or she can quickly switch to manual driving in response to a request from a system centered on the automatic driving control device 100. Note that, as used here, automatic driving refers to control of both steering and acceleration / deceleration without driver input. The term "ahead" refers to the space in the direction of travel of the host vehicle that can be seen through the front windshield. Mode A is a driving mode that can be implemented, for example, on a highway or other expressway, when certain conditions are met, such as the host vehicle traveling at a predetermined speed (e.g., approximately 50 km / h) or less and there is a vehicle ahead to be followed. Mode A is sometimes referred to as TJP (Traffic Jam Pilot). If these conditions are no longer met, the mode determination unit 150 changes the driving mode of the host vehicle to Mode B.

[0045] In mode B, the vehicle is in a driving assistance state, and the driver is tasked with monitoring the area ahead of the vehicle (hereinafter referred to as "forward monitoring"), but is not tasked with holding the steering wheel 82. In mode C, the vehicle is in a driving assistance state, and the driver is tasked with monitoring the area ahead and holding the steering wheel 82. Mode D is a driving mode in which the driver must perform some driving operation for at least one of steering and acceleration / deceleration of the vehicle. For example, in mode D, driving assistance such as ACC (Adaptive Cruise Control) and LKAS (Lane Keeping Assist System) is performed. In mode E, the vehicle is in a manual driving state in which the driver must perform both steering and acceleration / deceleration. In both mode D and mode E, the driver is naturally tasked with monitoring the area ahead of the vehicle.

[0046] The automatic driving control device 100 (and the driving assistance device (not shown)) executes an automated lane change according to the driving mode. There are two types of automated lane changes: a system-requested automated lane change (1) and a driver-requested automated lane change (2). The automated lane change (1) is performed when the speed of the vehicle ahead is slower than the speed of the vehicle itself by a certain standard, and includes an automated lane change for overtaking, and an automated lane change for proceeding toward the destination (an automated lane change due to a change in the recommended lane). The automated lane change (2) is performed when the driver operates the turn signal and conditions related to the speed and the positional relationship with surrounding vehicles are met, causing the vehicle to change lanes in the direction of the operation.

[0047] In mode A, the automatic driving control device 100 does not perform either automated lane change (1) or (2). In modes B and C, the automatic driving control device 100 performs either automated lane change (1) or (2). In mode D, the driving assistance device (not shown) does not perform automated lane change (1), but performs automated lane change (2). In mode E, neither automated lane change (1) nor (2) is performed.

[0048] When the driver does not perform a task related to the determined driving mode (hereinafter, the current driving mode), the mode determination unit 150 changes the driving mode of the vehicle to a driving mode that requires a heavier task.

[0049] For example, in mode A, if the driver is in a position where he or she cannot switch to manual driving in response to a request from the system (for example, if the driver continues to look away from the road outside the allowable area or if a sign of driving difficulty is detected), the mode determination unit 150 uses the HMI 30 to prompt the driver to switch to manual driving, and if the driver does not comply, the mode determination unit 150 performs control such as pulling the vehicle to the shoulder of the road and gradually stopping it, and stopping the automatic driving. After the automatic driving is stopped, the vehicle enters a state of mode D or E, and the driver can start the vehicle by manual operation. The same applies below to "stopping automatic driving." In mode B, if the driver is not monitoring the road ahead, the mode determination unit 150 performs control such as prompting the driver to monitor the road ahead using the HMI 30, and if the driver does not comply, pulling the vehicle to the shoulder of the road and gradually stopping it, and stopping the automatic driving. In mode C, if the driver is not monitoring the road ahead or is not gripping the steering wheel 82, the mode determination unit 150 uses the HMI 30 to prompt the driver to monitor the road ahead and / or grip the steering wheel 82, and if the driver does not comply, the mode determination unit 150 controls the vehicle to move to the shoulder of the road and gradually stop it, thereby terminating automatic driving.

[0050] The driver state determination unit 152 monitors the driver's state for the above mode change and determines whether the driver's state is appropriate for the task. For example, the driver state determination unit 152 analyzes the image captured by the driver monitor camera 70 and performs posture estimation processing to determine whether the driver is in a position that prevents the driver from switching to manual driving in response to a request from the system. The driver state determination unit 152 also analyzes the image captured by the driver monitor camera 70 and performs line-of-sight estimation processing to determine whether the driver is monitoring the road ahead.

[0051] The mode change processing unit 154 performs various processes for changing the mode. For example, the mode change processing unit 154 instructs the behavior plan generation unit 140 to generate a target trajectory for stopping on the shoulder of the road, instructs a driving assistance device (not shown) to operate, and controls the HMI 30 to prompt the driver to take action.

[0052] The second control unit 160 controls the traveling driving force output device 200, the braking device 210, and the steering device 220 so that the host vehicle passes along the target trajectory generated by the behavior plan generating unit 140 at the scheduled time.

[0053] Returning to FIG. 2, the second control unit 160 includes, for example, an acquisition unit 162, a speed control unit 164, and a steering control unit 166. The acquisition unit 162 acquires information on the target trajectory (trajectory points) generated by the action plan generation unit 140 and stores it in a memory (not shown). The speed control unit 164 controls the driving force output device 200 or the brake device 210 based on a speed element associated with the target trajectory stored in the memory. The steering control unit 166 controls the steering device 220 according to the curvature of the target trajectory stored in the memory. The processing of the speed control unit 164 and the steering control unit 166 is realized, for example, by a combination of feedforward control and feedback control. As an example, the steering control unit 166 executes a combination of feedforward control according to the curvature of the road ahead of the host vehicle and feedback control based on the deviation from the target trajectory.

[0054] The driving force output device 200 outputs a driving force (torque) for the vehicle to travel to the drive wheels. The driving force output device 200 includes, for example, a combination of an internal combustion engine, an electric motor, a transmission, etc., and an ECU (Electronic Control Unit) that controls these. The ECU controls the above components according to information input from the second control unit 160 or information input from the driving operator 80.

[0055] Braking device 210 may include, for example, a brake caliper, a cylinder that transmits hydraulic pressure to the brake caliper, an electric motor that generates hydraulic pressure in the cylinder, and a brake ECU. The brake ECU controls the electric motor according to information input from second control unit 160 or information input from driving operation device 80, so that a brake torque corresponding to the braking operation is output to each wheel. Braking device 210 may include a backup mechanism that transmits hydraulic pressure generated by operation of a brake pedal included in driving operation device 80 to the cylinder via a master cylinder. Note that braking device 210 is not limited to the configuration described above, and may also be an electronically controlled hydraulic brake device that controls an actuator according to information input from second control unit 160 to transmit hydraulic pressure from a master cylinder to the cylinder.

[0056] The steering device 220 includes, for example, a steering ECU and an electric motor. The electric motor applies a force to a rack and pinion mechanism to change the direction of the steered wheels. The steering ECU drives the electric motor in accordance with information input from the second control unit 160 or information input from the driving operator 80 to change the direction of the steered wheels.

[0057] The third control unit 180 determines whether the host vehicle is predicted to deviate from the lane while traveling around a curve (departure determination). More specifically, the third control unit 180 recognizes the positional relationship between the lane and the host vehicle and the traveling state of the host vehicle based on the recognition results of the object recognition device 16, the detection results of the vehicle sensor 40, map information (first map information and / or second map information), etc., and predicts the time until the host vehicle deviates from the lane if it continues traveling around the curve in its current traveling state (hereinafter referred to as TTLC (Time to Lane Crossing)). Then, the third control unit 180 determines that there is a high possibility that the host vehicle will deviate from the lane if the predicted TTLC is equal to or less than a predetermined time.

[0058] Generally, when a vehicle travels around a curve, the driver or a control function controls the steering angle and vehicle speed to prevent the vehicle from deviating from its lane. Such control changes from moment to moment depending on the vehicle's situation while traveling around the curve, changes in curvature, and the like. For this reason, the third control unit 180 repeatedly performs a departure determination at predetermined control intervals while the host vehicle is traveling around the curve. The third control unit 180 may be configured to execute predetermined processing depending on the result of the departure determination. For example, the third control unit 180 may be configured to notify the occupant of a predicted departure of the host vehicle via the HMI 30 or the navigation device 50 when a departure of the host vehicle is predicted. Furthermore, for example, the third control unit 180 may be configured to cooperate with the first control unit 120 and the second control unit 160 to control the vehicle speed and steering angle to prevent the host vehicle from deviating from its lane when a departure of the host vehicle is predicted.

[0059] [Basic flow of deviation judgment] FIG. 4 is a flowchart showing an example of the basic processing flow for deviation determination. FIG. 5 is a conceptual diagram for explaining an outline of deviation determination. The processing flow of FIG. 4 will be described below with reference to FIG. 5. First, the third control unit 180 acquires lane information for the lane on which the host vehicle is traveling (S101). The lane information is information that represents the lane markings of the lane on which the vehicle is traveling as a point cloud at a predetermined interval. Note that if the point cloud interval is too large, the accuracy of deviation determination decreases, while if the point cloud interval is too short, the control cycle for deviation determination becomes short and the processing load increases. Therefore, the point cloud interval should be designed to an appropriate interval (e.g., 1 meter interval) depending on the processing performance, the desired determination accuracy, and the like. Furthermore, if the lane markings to be processed in each control cycle are too long (i.e., too many point clouds), the processing load increases, while if the lane markings to be processed are too short, it becomes difficult to predict lane departure. Therefore, the length of the lane markings to be processed in each control cycle should be designed to an appropriate length (e.g., 100 meters) depending on the processing performance, the predictability of lane departure, and the like. For example, lane information may be acquired as a set of coordinates Pn={P1, P2, P3, ...} indicating the relative position of the lane markings with respect to the vehicle, for lane markings farther from the center of curvature of the curve, as shown in Fig. 5. Hereinafter, this set Pn will be referred to as a lane marking point cloud Pn.

[0060] Next, the third control unit 180 calculates a predicted route of the host vehicle based on the vehicle speed and yaw rate of the host vehicle (S102) and determines whether the predicted route intersects with a lane marking (S103: intersection determination). If it is determined that the predicted route does not intersect with the lane marking, i.e., if there is no intersection between the predicted route and the lane marking, the third control unit 180 ends the deviation determination for that cycle. On the other hand, if it is determined in S103 that the predicted route intersects with the lane marking, i.e., if there is an intersection between the predicted route and the lane marking, the third control unit 180 calculates a predicted time (TTLC) until the host vehicle reaches the position of the intersection (S104) and determines whether the TTLC is equal to or less than a predetermined threshold (S105). If it is determined that the predicted time is greater than the threshold, the third control unit 180 ends the deviation determination for that cycle. On the other hand, if it is determined in S105 that the predicted time is equal to or less than the threshold value, the third control unit 180 notifies the driver that the vehicle is about to deviate from the lane (S106: departure notification) and ends the departure determination for that period.

[0061] FIG. 5 shows an example in which the predicted route R of the host vehicle intersects with the line segment S7 formed by P7 and P8 of the lane marking point group Pn. In this case, the third control unit 180 calculates the predicted route R of the host vehicle and determines whether or not the predicted route R intersects with line segments n (n=1, 2, ...) formed by two adjacent points of the lane marking point group Pn, starting with the line segment closest to the host vehicle. Here, line segment n is the line segment formed by Pn and Pn+1. In the example of FIG. 5, the third control unit 180 determines whether or not the predicted route R intersects with the line segment S7 (n=7) by determining whether or not the predicted route R intersects with the line segment S1 (n=1) in order (intersection determination). Hereinafter, the point where the predicted route intersects with the lane marking is referred to as the "deviation point." The third control unit 180 can calculate the time required for the host vehicle to reach the deviation point B from its initial position as TTLC.

[0062] More specifically, the third control unit 180 calculates the movement trajectory of the part of the host vehicle that is most likely to intersect (deviate from) the lane marking line first (hereinafter referred to as the "target part") as the predicted route R of the host vehicle. Here, as an example, the outer edge of the right front tire of the host vehicle is the target part, but other parts may be the target part from a similar perspective. For example, the ground contact point of the right front tire may be the target part, or the right edge of the front of the vehicle body may be the target part. The third control unit 180 can calculate the distance d from the initial position A of the target part to the deviation point B (hereinafter referred to as the "deviation path length") and calculate the TTLC by dividing the deviation path length d by the moving speed of the target part.

[0063] Returning to FIG. 4, the notification in S105 (hereinafter referred to as "departure notification") may be in the form of information displayed by the HMI 30 or the navigation device 50, or may be audio output by the navigation device 50. Furthermore, the departure notification may be in the form of output of a determination result to another functional unit (e.g., the first control unit 120 or the second control unit 160). In this case, the other functional unit may be configured to perform a predetermined operation upon receiving the departure notification. For example, the first control unit 120 may be configured to generate a target trajectory that suppresses lane departure in accordance with the driving state of the host vehicle at that time upon receiving the departure notification. Furthermore, for example, the second control unit 160 may be configured to perform speed control and / or steering control in order to suppress lane departure in accordance with the driving state of the host vehicle at that time upon receiving the departure notification.

[0064] If the TTLC threshold is too high, the threshold for deviation notification will be lowered, resulting in notifications for situations that do not require much attention being sent. This may increase the risk of deviation notifications requiring high attention being mixed in with other deviation notifications. Furthermore, if the TTLC threshold is too high, deviation notifications will be sent more frequently, which may be more annoying to occupants. On the other hand, if the TTLC threshold is too low, there may not be enough time to recover the vehicle's behavior after receiving a deviation notification, which may increase the risk. Therefore, the TTLC threshold should be designed to an appropriate value (e.g., 1 second) from the perspective of occupant comfort and safety.

[0065] Furthermore, if the control cycle is too short, the number of point clouds that can be processed will decrease, while if the control cycle is too long, lane departure will not be detected at the required timing. Therefore, the control cycle should be designed to an appropriate value (e.g., 10 milliseconds) from the perspective of the number of point clouds to be processed in one cycle and the required timing for detecting lane departure. Each of the above design elements should be set appropriately to achieve an appropriate combination of values ​​in balance with other design elements.

[0066] [Turning speed and turning center of your vehicle] FIG. 6 is a diagram illustrating a method for calculating the turning speed and turning center of the host vehicle when traveling around a curve in deviation judgment. As explained in FIG. 5, calculation of the deviation path length requires predicting the traveling path of the host vehicle. It is considered that the host vehicle traveling around a curve (curvature X) makes a turning motion on the circumference of the circle with curvature X. For this reason, in this embodiment, in order to predict the traveling path of the host vehicle, the position of the center of turning motion (turning center) is first obtained. FIG. 6 shows a situation in which the host vehicle is making a turning motion at a speed v around the turning center O. Here, the moving direction of the host vehicle is the normal direction (direction of vector v) at point G on the circumference whose radius is the length from the turning center O to the center (center of gravity) G of the host vehicle. The x-y coordinate system in FIG. 6 is an orthogonal coordinate system with the center G of the host vehicle as the origin, and the x-axis is an axis parallel to the forward direction of the host vehicle. In this case, the speed v at which the position of the target part (hereinafter simply referred to as tire) changes is tyrecan be expressed by the following equation (1).

[0067]

number

[0068] In equation (1), v x_tyre is the velocity v tyre is the x-component of v y_tyre is the velocity v tyre The y-component of the vehicle is the yaw rate. x is the x-component of the moving speed v of the center G of the vehicle, and v y is the y-component. Tx is the x-coordinate component of the tire's position, and Ty is the y-coordinate component. Equation (1) is obtained by combining rotational motion and translational motion based on the equation of motion of a rigid body. In this case, the turning radius of the tire can be expressed by the following equation (2).

[0069]

number

[0070] 7, 8 and 9 are diagrams for explaining a method for calculating the deviation path length of the host vehicle when traveling around a curve in deviation judgment. More specifically, the method for calculating the deviation path length is divided into a first step of obtaining a first coordinate, a second step of obtaining a second coordinate, and a third step of obtaining the deviation path length based on the results of the first and second steps. FIGS. 7, 8 and 9 show a method for calculating the deviation path length when the tire movement trajectory (i.e., predicted path) of the host vehicle making a turning motion around the turning center O coincides with two adjacent points (P Beg and P End ) intersects with a line segment formed by the line segment at a deviation point C. Hereinafter, this line segment will be referred to as the "intersecting line segment."

[0071] FIG. 7 is a diagram illustrating a method for calculating the first coordinate in the first step. In the first step, the third control unit 180 calculates P BegThe coordinates of the projected (first coordinates) of the third vertex D of the right triangle with the first vertex P as the first vertex and the center of rotation O as the second vertex are calculated. Beg The coordinates (segBeg) of the second vertex O are known by finding the deviation point C, and the coordinates (v c ) is the initial position of the tire and the tire movement speed v calculated by the method explained in Figure 6. tyre and turning radius R tyre In this case, the third control unit 180 calculates the first vertex P by taking the inner product of the vectors as shown in the following equation (3). Beg The ratio of the length from the point to the third vertex D to the length of the intersecting line segment h can be obtained.

[0072]

number

[0073] In equation (3), v s HA P Beg From P End is a vector pointing towards v p HA P Beg is a vector from the center of rotation O. φ is a vector v s and v p Next, the third control unit 180 calculates the ratio calculated by the formula (3). h Based on this, the coordinate projected of the third vertex D can be found by performing the vector calculation of the following equation (4).

[0074]

number

[0075] FIG. 8 is a diagram illustrating a method for calculating the second coordinates in the second step. In the second step, the third control unit 180 calculates the coordinates (second coordinates) of the departure point C based on the first coordinates (projected) calculated in the first step. First, the third control unit 180 calculates the distance s from the turning center O to the third vertex D using the following equation (5). In equation (5), v c are the coordinates of the turning center O.

[0076]

number

[0077] Next, the third control unit 180 calculates the distance t from the departure point C to the third vertex D by the following equation (6). In equation (6), R tyre is the turning radius of tire T calculated using equation (2).

[0078]

number

[0079] Next, the third control unit 180 can obtain the coordinates of the departure point C (departurePoint) using the following equation (7).

[0080]

number

[0081] 9 is a diagram illustrating a method for calculating the deviation path length d in the third step. First, the third control unit 180 calculates the angle θ between the line segment connecting the turning center O and the deviation point C and the straight line L passing through the turning center O and parallel to the y-axis, using the following equation (8): Dep In equation (8), v x is the length of the perpendicular line drawn from the departure point C to the line L, and is the y-coordinate of the turning center O, the y-coordinate of the departure point C, and the turning radius R tyre It is calculated based on v yis the length of the line segment connecting the foot of the perpendicular line and the turning center O, and is calculated based on the y coordinate of the turning center O and the y coordinate of the departure point C.

[0082]

number

[0083] Next, the third control unit 180 calculates the angle θ between the line segment connecting the turning center O and the initial position of the tire T and the straight line L using the following equation (9): ini If the turning direction is the positive direction with the straight line L as the reference, then θ Dep is a positive angle, and θ ini Since is a negative angle, the θ calculated by equation (8) Dep From θ ini The difference between the initial position (initial position of tire T) and the departure point C is the angle that the vehicle turns from the initial position (initial position of tire T). x ′ is the length of the perpendicular line drawn from the initial position to the line L, and is calculated based on the x coordinate of the initial position and the x coordinate of the turning center O. y ′ is the length of the line segment connecting the foot of the perpendicular line and the center of rotation O, and is calculated based on the y coordinate of the initial position and the y coordinate of the center of rotation O.

[0084]

number

[0085] Then, the third control unit 180 can obtain the deviation path length d by the following equation (10).

[0086]

number

[0087] The third control unit 180 calculates the deviation path length d and the turning speed v obtained as described above. tyreBased on this, the time required for the vehicle to reach the departure point C from the initial position (i.e., TTLC) can be calculated. When the vehicle is traveling on a curve, θ ini is θ Dep In such a case, the third control unit 180 may adjust the angle θ as long as the accuracy of the deviation determination is acceptable. ini The processing load for the deviation determination may be reduced by approximating θ to zero to reduce the amount of calculation. ini Approximating to zero means that the initial position of the tire T is set on the straight line L. As a result, the third control unit 180 sets the turning center O to the side of the host vehicle.

[0088] According to the embodiment described above, deviation judgment can be made based on the predicted path of the vehicle as it turns, making it possible to more appropriately make deviation judgment when the vehicle is traveling around a curve.

[0089] In the above embodiment, a case where departure determination is performed when the host vehicle is traveling around a curve has been described, but departure determination using the above method may also be performed when the host vehicle is traveling around a curve. In this case, the third control unit 180 may calculate the predicted route of the host vehicle using a method different from the above method. For example, when the host vehicle is traveling in a substantially straight line (when the yaw rate is sufficiently small), the third control unit 180 may calculate the predicted route based on the vehicle speed, acceleration, traveling direction, etc. of the host vehicle. Furthermore, for example, the third control unit 180 may use information on the route that the host vehicle has traveled up to the current control cycle in calculating the predicted route.

[0090] In the above embodiment, the initial position of the host vehicle is set to the position of the front tire T far from the turning center, and a predicted path is calculated starting from that initial position. However, the position of the tire T may be a ground contact point, or the initial position may be set to an end of the front of the vehicle body close to the tire T. In other words, the initial position of the host vehicle may be set to an end or a ground contact point of the vehicle body that is closest to the intersection segment. In this case, θ iniIf is sufficiently small, it can be said that the turning center O is set in a direction perpendicular to the front direction of the vehicle from the end portion close to the intersection segment or the contact point.

[0091] The above-described embodiment can be expressed as follows. a storage device storing a program; a hardware processor; The hardware processor executes the program, Recognizes the dividing lines of the road on which the vehicle is traveling, Calculating a predicted route of the vehicle based on the driving state of the vehicle; determining whether or not the lane markings intersect with the predicted route for each predetermined section of the lane markings; When it is determined that the predicted route will intersect with a lane marking in the predetermined section, a margin time until the host vehicle reaches the intersection of the predicted route and the lane marking is calculated, and when the margin time is equal to or less than a threshold, it is determined that there is a high possibility that the host vehicle will deviate from the lane marking. Vehicle control device.

[0092] The above describes the form for carrying out the present invention using an embodiment, but the present invention is not limited to such an embodiment, and various modifications and substitutions can be made within the scope that does not deviate from the gist of the present invention. [Explanation of symbols]

[0093] 1 Vehicle System 10 Camera 12 Radar equipment 14 LIDAR 16 Object recognition device 20. Communication Equipment 30 HMI(Human Machine Interface) 40 Vehicle Sensors 50 Navigation equipment 51 GNSS (Global Navigation Satellite System) receiver 52 Navigation HMI 53 Route determination unit 54 First Map Information 60 MPU (Map Positioning Unit) 61 Recommended lane determination unit 62 Second Map Information 70 Driver monitor camera 80 Driving controls 82 Steering wheel 84 Steering grip sensor 100 Automatic driving control device 120 First Control Section 130 Recognition part 140 Action Plan Generation Unit 150 Mode determination unit 152 Driver state determination unit 154 Mode change processing section 160 Second Control Section 162 Acquisition Department 164 Speed ​​control section 166 Steering control unit 180 Third Control Section 200 Driving force output device 210 Brake equipment 220 Steering device

Claims

1. a recognition unit that recognizes lane markings on a road on which the vehicle is traveling; a prediction unit that calculates a predicted route of the host vehicle based on a traveling state of the host vehicle; an intersection determination unit that determines whether or not the lane markings intersect with the predicted route for each predetermined section of the lane markings; a determination unit that, when it is determined that the predicted route will intersect with a lane marking in the predetermined section, calculates a margin of time until the host vehicle reaches the intersection of the predicted route and the lane marking, and, when the margin of time is equal to or less than a threshold, determines that there is a high possibility that the host vehicle will deviate from the lane marking; A vehicle control device comprising:

2. the intersection determination unit calculates the predicted path based on a turning curve based on a current traveling state of the host vehicle when the host vehicle is traveling with a turning motion; The vehicle control device according to claim 1 .

3. When the host vehicle is traveling while making a turn, the determination unit calculates the margin time based on a turning curve based on a current traveling state of the host vehicle. The vehicle control device according to claim 1 .

4. The center of the turning curve is set to the side of the vehicle. The vehicle control device according to claim 2 or 3.

5. the center is set in a direction perpendicular to a direction forward in front of the vehicle from an end or a ground contact point of the vehicle that is closest to the predetermined section, The vehicle control device according to claim 4.

6. A control device of the host vehicle, Recognizes the dividing lines of the road on which the vehicle is traveling, Calculating a predicted route of the vehicle based on the driving state of the vehicle; determining whether or not the lane markings intersect with the predicted route for each predetermined section of the lane markings; When it is determined that the predicted route will intersect with a lane marking in the predetermined section, a margin time until the host vehicle reaches the intersection of the predicted route and the lane marking is calculated, and when the margin time is equal to or less than a threshold, it is determined that there is a high possibility that the host vehicle will deviate from the lane marking. Vehicle control method.

7. The control device of the vehicle Recognizes the dividing lines on the road on which the vehicle is traveling, Calculating a predicted route of the vehicle based on the driving state of the vehicle; determining whether or not the lane markings intersect with the predicted route for each predetermined section of the lane markings; when it is determined that the predicted route will intersect with a lane marking in the predetermined section, calculating a margin time until the host vehicle reaches the intersection of the predicted route and the lane marking, and when the margin time is equal to or less than a threshold, determining that there is a high possibility that the host vehicle will deviate from the lane marking. Program for.

Images