Vehicle control device, vehicle control method, and program

Abstract

To perform more appropriate vehicle control according to a surrounding situation of a vehicle before performing control for avoidance of collision between the vehicle and an obstacle.SOLUTION: A vehicle control device of an embodiment comprises: a recognition unit configured to recognize a surrounding situation of an own vehicle; and a control unit configured to control one or both of steering and acceleration / deceleration of the own vehicle when an obstacle exists in front of the own vehicle based on a recognition result of the recognition unit. Therein: when it is determined that the obstacle exists in front of the vehicle, the control unit executes at least a steering control for moving the own vehicle to a center of a traveling traffic lane; and the control unit discontinues the steering control when a recognition degree of a compartment line that divides the traveling lane in which the own vehicle travels by the recognition unit at an execution time of the steering control is less than a threshold value.SELECTED DRAWING: Figure 1

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, efforts are being focused on research and development to further improve traffic safety and convenience through research and development of preventive safety technologies. In this regard, a technology has been disclosed in recent years that estimates whether or not a collision will occur between a vehicle behind an obstacle when the vehicle avoids the obstacle by either changing lanes or steering, and determines the avoidance action based on the estimated collision (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-151185 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in preventive safety technology, the vehicle behavior to alert the vehicle occupants to the surrounding area before performing contact avoidance control between the vehicle and an obstacle has not been considered, and the vehicle behavior that should be performed depending on the surrounding conditions has not been considered. Therefore, in the past, there was an issue that the vehicle could not be controlled appropriately depending on the surrounding conditions.

[0005] In order to solve the above-mentioned problems, one of the objects of the present application is to provide a vehicle control device, a vehicle control method, and a program that can perform more appropriate vehicle control in accordance with the surrounding conditions of the vehicle before performing control to avoid contact between the vehicle and an obstacle, thereby contributing to the development of a sustainable transportation system. [Means for solving the problem]

[0006] The vehicle control device, vehicle control method, and program according to the present invention employ the following configuration. (1): A vehicle control device according to one embodiment of the present invention includes a recognition unit that recognizes the surrounding conditions of the host vehicle, and a control unit that controls one or both of the steering and acceleration / deceleration of the host vehicle when an obstacle is present ahead of the host vehicle based on the recognition results of the recognition unit. When it is determined that an obstacle is present ahead of the host vehicle, the control unit executes steering control to move the host vehicle to the center of the driving lane, and when the steering control is executed, if the recognition unit's degree of recognition of the dividing line that separates the driving lane in which the host vehicle is traveling is less than a threshold value, the control unit stops the steering control.

[0007] (2): In the above aspect (1), when the recognition degree of the marking line closer to the vehicle, of the two marking lines that define the driving lane, is equal to or greater than a threshold value, and the recognition degree of the marking line farther from the vehicle is less than the threshold value, the control unit causes the vehicle to travel along the marking line closer to the vehicle.

[0008] (3): In the above aspect (1), the control unit executes deceleration control to slow down the vehicle when an obstacle is present in front of the vehicle, and continues the deceleration control even when the recognition unit's degree of recognition of the dividing line that separates the lane in which the vehicle is traveling falls below a threshold value during the execution of the deceleration control.

[0009] (4): In the above aspect (3), the vehicle further includes a notification control unit that issues a notification indicating that at least one of the steering control and the deceleration control has been completed by the control unit, and the notification control unit does not issue a notification indicating that the steering control has been completed if the recognition unit's degree of recognition of the lane markings that define the lane in which the vehicle is traveling falls below a threshold value during the execution of the steering control, and the deceleration control continues even if the steering control is discontinued.

[0010] (5) In the above aspect (1), the control unit stops the steering control when the state in which the degree of recognition is less than the threshold value continues for a predetermined time or more.

[0011] (6) Another aspect of the present invention is a vehicle control method in which a computer recognizes the surrounding conditions of a host vehicle, and based on the recognition results, performs driving control to control one or both of the steering and acceleration / deceleration of the host vehicle when an obstacle is present in front of the host vehicle, and the driving control performs steering control to move at least the host vehicle to the center of the driving lane when it is determined that an obstacle is present in front of the host vehicle, and when the steering control is performed, the steering control is discontinued when the degree of recognition of the dividing line that separates the driving lane in which the host vehicle is traveling is less than a threshold value.

[0012] (7): Another aspect of the present invention provides a program that causes a computer to recognize the surrounding conditions of a host vehicle, and, based on the recognition results, executes driving control to control one or both of the steering and acceleration / deceleration of the host vehicle when an obstacle is present in front of the host vehicle. The driving control executes steering control to move the host vehicle to the center of the driving lane when it is determined that an obstacle is present in front of the host vehicle, and when the steering control is executed, the program stops the steering control when the degree of recognition of the dividing line that separates the driving lane in which the host vehicle is traveling is less than a threshold value. [Effects of the Invention]

[0013] According to the above aspects (1) to (7), more appropriate vehicle control can be performed in accordance with the surrounding conditions of the vehicle before control for avoiding contact between the vehicle and an obstacle is performed. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a configuration diagram of a host vehicle M equipped with a vehicle control device according to an embodiment. [Figure 2] FIG. 2 is a diagram for explaining the content of vehicle control relating to contact avoidance. [Figure 3] FIG. 10 is a diagram for explaining the details of attention-attraction control. [Figure 4] FIG. 10 is a diagram for explaining the content of contact warning control. [Figure 5] FIG. 10 is a diagram for explaining the content of automatic steering avoidance control. [Figure 6] FIG. 10 is a diagram for explaining steering control after a driver steering trigger. [Figure 7] FIG. 2 is a diagram illustrating a first embodiment of centering steering control. [Figure 8] FIG. 10 is a diagram illustrating a second embodiment of centering steering control. [Figure 9] FIG. 10 is a diagram illustrating a third embodiment of centering steering control. [Figure 10] FIG. 10 is a diagram illustrating a fourth embodiment of centering steering control. [Figure 11] 10A and 10B are diagrams for explaining a lane center error range and a lateral position error range. [Figure 12] FIG. 10 is a diagram illustrating a fifth embodiment of centering steering control. [Figure 13] FIG. 10 is a diagram illustrating a sixth embodiment of centering steering control. [Figure 14] 3 is a flowchart showing an example of processing executed by the driving assistance device 100 in the embodiment. [Figure 15] 10 is a flowchart showing an example of a centering steering control process. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 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 accompanying drawings.

[0016] [Overall configuration] 1 is a configuration diagram of a host vehicle M equipped with a vehicle control device according to an embodiment. The host vehicle M 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.

[0017] The host vehicle M is equipped with, 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, a driving assistance 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 multiplex 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. The HMI 30 is an example of a "notification unit." The driving assistance device 100 is an example of a "vehicle control device."

[0018] The camera 10 is, for example, a digital camera that uses 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 on the vehicle M. 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 and repeatedly captures images of the surroundings of the vehicle M. The camera 10 may be a stereo camera.

[0019] The radar device 12 emits radio waves such as millimeter waves around the vehicle M and detects radio waves reflected by an object (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 M. The radar device 12 may detect the position and speed of an object using an FM-CW (Frequency Modulated Continuous Wave) method.

[0020] The LIDAR 14 irradiates the surroundings of the vehicle M 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 is attached to any location on the vehicle M.

[0021] 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 driving assistance 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 driving assistance device 100. The object recognition device 16 may be omitted from the host vehicle M. Some or all of the camera 10, the radar device 12, the LIDAR 14, and the object recognition device 16 are examples of "external environment detection devices."

[0022] The communication device 20 communicates with other vehicles in the vicinity of the vehicle M, for example, using a cellular network, a Wi-Fi network, Bluetooth (registered trademark), DSRC (Dedicated Short Range Communication), etc., or communicates with various server devices via a wireless base station.

[0023] The HMI 30 presents various information to the occupants of the vehicle M and accepts input operations by the occupants. The HMI 30 includes, for example, a display unit 32 and a speaker 34. The display unit 32 is, for example, an LCD (Liquid Crystal Display) or an organic EL (Electro Luminescence) display device. The display unit 32 displays various images (including videos) in the embodiment. The display unit 32 may be configured integrally with the input unit as a touch panel. The speaker 34 outputs a predetermined sound (for example, an alarm). Furthermore, the HMI 30 may include, in addition to (or instead of) the display unit 32 and the speaker 34, a microphone, a buzzer, a vibration generator (vibrator), a touch panel, a switch, a key, or the like.

[0024] The vehicle sensor 40 includes a vehicle speed sensor that detects the speed of the host vehicle M, an acceleration sensor that detects acceleration, a yaw rate sensor that detects the yaw rate (for example, the rotational angular velocity around a vertical axis passing through the center of gravity of the host vehicle M), a direction sensor that detects the orientation of the host vehicle M, and a steering angle sensor that detects the steering angle of the host vehicle M (which may be the angle of the steering wheels or the operating angle of the steering wheel). The vehicle sensor 40 may also be provided with a position sensor that detects the position of the host vehicle M. The position sensor is, for example, a sensor that acquires position information (longitude and latitude information) from a GPS (Global Positioning System) device. The position sensor may also be a sensor that acquires position information using a GNSS (Global Navigation Satellite System) receiver 51 of the navigation device 50.

[0025] The navigation device 50 includes, for example, a GNSS 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 identifies the position of the vehicle M based on signals received from GNSS satellites. The position of the vehicle M may be identified 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 M identified by the GNSS receiver 51 (or any input position) to a destination input by the occupant using the navigation HMI 52, with reference 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 carried 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.

[0026] 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, every 100 m in the vehicle 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. Furthermore, when there is a branch point on the route on the map, the recommended lane determination unit 61 determines the recommended lane so that the vehicle M can travel on a reasonable route to the branch point. 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, lane boundary information such as road dividing lines (hereinafter referred to as dividing lines) that divide lanes, etc. The second map information 62 may include road information, traffic regulation information, address information (address and postal code), facility information, telephone number information, etc. The second map information 62 may be updated as needed by the communication device 20 communicating with other devices. The first map information 54 and the second map information 62 may be stored in a storage unit within the driving assistance device 100.

[0027] The driver monitor camera 70 is, for example, a digital camera that uses a solid-state imaging element such as a CCD or CMOS. The driver monitor camera 70 is attached to any location on the vehicle M in a position and orientation that allows it to capture an image of the head and upper body (including the position of the hands) of an occupant (hereinafter referred to as the driver) seated in the driver's seat of the vehicle M 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 M. The driver monitor camera 70 outputs an image of the interior of the vehicle, including the driver of the vehicle M, captured from its installed position to the driving assistance device 100.

[0028] The driving operators 80 include, for example, a steering wheel 82, an accelerator pedal 84, a brake pedal 86, a turn signal switch, a shift lever, and other operators. The driving operators 80 are fitted with sensors that detect the amount of operation or the presence or absence of operation, and the detection results are output to the driving assistance device 100 or some or all of the driving force output device 200, the braking device 210, and the steering device 220.

[0029] For example, the steering wheel 82 is provided with a steering wheel sensor (SW sensor) 82A. The SW sensor 82A detects whether or not the driver is gripping the steering wheel 82. The SW sensor 82A also detects the amount of operation of the steering wheel 82 by the driver (amount of steering torque, steering amount). The steering wheel 82 does not necessarily have to be annular, and may be in the form of an irregularly shaped steering wheel, a joystick, buttons, or the like. In this case, the SW sensor 82A detects the amount of operation according to the respective form.

[0030] An accelerator pedal sensor (AP sensor) 84A is attached to the accelerator pedal 84. The AP sensor 84A detects the amount of operation (opening) of the accelerator pedal 84, which changes in response to the driver's operation of the accelerator pedal 84. A brake pedal sensor (BP sensor) 86A is provided to the brake pedal 86. The BP sensor 86A detects the amount of operation (opening) of the brake pedal 86, which changes in response to the driver's operation of the brake pedal 86.

[0031] The driving force output device 200 outputs a driving force (torque) to the driving wheels for driving the host vehicle M. 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 in accordance with information input from the driving assistance device 100 or information input from the driving operator 80.

[0032] Braking device 210 includes, 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 an ECU. The ECU controls the electric motor according to information input from driving assistance device 100 or information input from driving operator 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 operator 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 driving assistance device 100 to transmit hydraulic pressure from a master cylinder to the cylinder.

[0033] The steering device 220 includes, for example, a steering ECU and an electric motor. The electric motor applies force to a rack and pinion mechanism to change the direction of the steered wheels. The steering ECU drives the electric motor to change the direction of the steered wheels in accordance with information input from the driving assistance device 100 or information input from the driving operator 80.

[0034] [Driving assistance devices] The driving assistance device 100 includes, for example, a recognition unit 110, a driving state detection unit 120, a contact possibility determination unit 130, a control unit 140, an HMI control unit 150, and a storage unit 160. The recognition unit 110, the driving state detection unit 120, the contact possibility determination unit 130, the control unit 140, and the HMI control unit 150 are realized by, for example, a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Furthermore, 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 an HDD or flash memory of the driving assistance 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 driving assistance device 100 by inserting the storage medium (non-transitory storage medium) into a drive device. The HMI control unit 150 is an example of a "notification control unit."

[0035] For example, settings are made within the driving force output device 200, the braking device 210, and the steering device 220 so that instructions from the driving support device 100 to the driving force output device 200, the braking device 210, and the steering device 220 are executed with priority over detection results from the driving operator 80. Regarding braking, if the braking force based on the operation amount of the brake pedal 86 is greater than the instruction from the driving support device 100, the latter may be set to be executed with priority. Furthermore, communication priority in an in-vehicle local area network (LAN) may be used as a mechanism for executing instructions from the driving support device 100 with priority.

[0036] The storage unit 160 may be realized by the various storage devices described above, or a solid state drive (SSD), an electrically erasable programmable read only memory (EEPROM), a read only memory (ROM), or a random access memory (RAM). The storage unit 160 stores, for example, programs and various other information. The storage unit 160 may also store the map information described above (first map information 54, second map information 62).

[0037] The recognition unit 110 recognizes the surrounding conditions of the host vehicle M based on information input from an external environment detection device. For example, the recognition unit 110 recognizes the position, speed, acceleration, and other status of objects present in the vicinity (e.g., within a predetermined distance from the host vehicle M). Examples of objects include other vehicles, bicycles, pedestrians, etc. The position of an object is recognized as a position on an absolute coordinate system with a representative point of the host vehicle M (e.g., 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 may be represented by an area. The "state" of an object may include the acceleration or jerk of the object, or the "behavior state" (e.g., whether or not the object is changing lanes or is about to change lanes). The recognition unit 110 also recognizes the relative position and relative speed of the object.

[0038] The recognition unit 110 also recognizes, for example, the lane in which the host vehicle M is traveling (driving lane). For example, the recognition unit 110 performs known analysis processing (e.g., edge extraction, feature extraction, pattern matching processing, etc.) on an image captured by the camera 10 (hereinafter, referred to as a camera image), and recognizes the position and pattern of marking lines around the host vehicle M (e.g., an arrangement of solid and dashed lines) from the analysis results. The recognition unit 110 may also refer to map information (second map information 62) based on the position information of the host vehicle M to recognize the position and pattern of marking lines around the host vehicle M. The recognition unit 110 may also recognize the driving lane using at least one of the positions and patterns of marking lines obtained from the camera image and the positions and patterns of marking lines obtained from the map information. The recognition unit 110 may recognize the driving lane by recognizing road boundaries (road boundaries) including not only marking lines but also shoulders, curbs, medians, guardrails, etc. In this recognition, the position of the host vehicle M obtained from the navigation device 50 and processing results from the INS may be taken into account. The recognition unit 110 may also recognize adjacent lanes adjacent to the driving lane. The recognition unit 110 also recognizes obstacles, stop lines, red lights, toll booths, and other road phenomena from the object recognition results. Obstacles are objects that the host vehicle M needs to avoid contacting, and include, for example, other vehicles.

[0039] The recognition unit 110 may also derive a recognition degree of the lane markings that demarcate the driving lane based on the results of analyzing the camera image. The recognition degree of the lane markings is an index value (recognition reliability) that indicates the existence of the lane markings (the likelihood of recognition), and the higher the recognition degree, the higher the index value. For example, the recognition unit 110 may compare the position and pattern of the lane markings obtained from the camera image with the position and pattern of the lane markings obtained from map information, and derive a recognition degree based on the degree of match (or deviation). Furthermore, if the recognition unit 110 recognizes a broken or unclear portion due to rubbing, loss, or the like in the lane markings obtained from the camera image, it may reduce the recognition degree based on the extent of the broken portion. The recognition unit 110 may derive a recognition degree for each of the left and right lane markings that demarcate the driving lane, or may average the recognition degrees of the left and right lane markings. The recognition unit 110 may also derive the recognition degree of a marking line that marks a lane other than the driving lane present around the vehicle M (for example, an adjacent lane).

[0040] The recognition unit 110 may also recognize the position and attitude of the host vehicle M with respect to the driving lane. For example, the recognition unit 110 may recognize the deviation of the reference point of the host vehicle M from the center of the lane and the angle it forms with a line connecting the centers of the lanes in the traveling direction of the host vehicle M as the relative position and attitude of the host vehicle M with respect to the driving lane. Alternatively, the recognition unit 110 may recognize the position of the reference point of the host vehicle M with respect to either side edge of the driving lane (a road dividing line or a road boundary) as the relative position of the host vehicle M with respect to the driving lane. The recognition unit 110 may also recognize the position and attitude of other vehicles traveling in the driving lane of the host vehicle M, or recognize whether the other vehicles are located on the center side of the driving lane or on the dividing line side as viewed from the host vehicle M.

[0041] The driving state detection unit 120 detects a predetermined driving state of an occupant (driver) of the host vehicle M. The predetermined driving state is, for example, a mindless driving state. Mindless driving is a state in which the driver's driving operation of the host vehicle M becomes slow (or does not operate) due to a decrease in the driver's attention, etc. For example, the driving state detection unit 120 detects the driver's mindless driving state when the steering operation of the steering wheel 82 by the driver remains below a threshold (a determination threshold TH1 described later) for a predetermined time or more based on the detection result of the SW sensor 82A. Alternatively, the driving state detection unit 120 may detect the driver's mindless driving state when the change in the opening degree of the accelerator pedal 84 and the brake pedal 86 remains below a threshold for a predetermined time or more based on the detection results of the AP sensor 84A and the BP sensor 86A. Note that the above-mentioned predetermined time may be variably set depending on, for example, the speed of the host vehicle M, the margin of safety before the host vehicle M comes into contact with an obstacle (e.g., another vehicle), etc. This allows for a more appropriate determination of absentminded driving to be made based on the speed of the host vehicle M and the positional relationship between the host vehicle M and the obstacle. Note that the predetermined time may be a fixed time.

[0042] Furthermore, the driving state detection unit 120 may detect that the driver is in a careless driving state when it is determined that the state of the driver detected based on the analysis result of the image captured by the driver monitor camera 70 is not suitable for driving. A state that is not suitable for driving is, for example, when the driver is not monitoring the surroundings (particularly the front) of the vehicle M due to looking away, or when it is predicted that the driver's concentration is declining based on facial expressions (a face that looks sleepy, a face that looks pained), etc.

[0043] Furthermore, the driving state detection unit 120 may detect the details of the driver's driving operation. For example, the driving state detection unit 120 may detect the driver's steering amount (torque amount of steering torque) based on the detection result of the SW sensor 82A, may detect the operation (opening degree) of the accelerator pedal 84 based on the detection result of the AP sensor 84A, or may detect the operation (opening degree) of the brake pedal 86 based on the BP sensor 86A. Furthermore, the driving state detection unit 120 may detect a state in which the driver is not driving.

[0044] The contact possibility determination unit 130 recognizes whether or not there is a possibility of contact between the host vehicle M and an obstacle (e.g., another vehicle) based on the surrounding conditions (external environment information) recognized by the recognition unit 110. For example, the contact possibility determination unit 130 determines whether or not there is a possibility of contact between the host vehicle M and another vehicle based on a contact margin value with respect to another vehicle (leading vehicle) present ahead of the host vehicle M based on the surrounding conditions. The contact margin value is, for example, a value set based on a time to collision (TTC), but may also be a value set based on a time headway (THW). The time to collision (TTC) is derived, for example, by dividing the relative distance by the relative speed in the relationship between the host vehicle M and the other vehicle. Furthermore, the time headway (THW) is derived, for example, by dividing the relative distance (inter-vehicle distance) by the speed of the host vehicle M. The time to contact TTC may be derived using, for example, a trained model or a predetermined function that outputs the time to contact TTC when the positions and speeds of the host vehicle M and the other vehicle are input, or may be derived using a correspondence table that associates the relative speed and relative position with the time to contact TTC. The above derivation method also applies to the time to headway THW. For example, the shorter the time to contact TTC (or the time to headway THW), the smaller the contact margin value (in other words, the longer the contact margin time, the larger the contact margin value). For example, the contact possibility determination unit 130 determines that there is a possibility of contact between the host vehicle M and the other vehicle when the contact margin value is less than a threshold, and determines that there is no possibility of contact when the contact margin value is equal to or greater than the threshold.

[0045] The control unit 140 controls one or both of the steering and acceleration / deceleration of the host vehicle M based on at least one of the recognition result of the recognition unit 110, the detection result of the driving state detection unit 120, and the determination result of the contact possibility determination unit 130. The control unit 140 includes, for example, a braking control unit 142 and a steering control unit 144.

[0046] When it is determined based on the recognition result of the recognition unit 110 that an obstacle is present ahead of the host vehicle M, the braking control unit 142 performs at least deceleration control of the host vehicle M based on a target deceleration of the host vehicle M. Furthermore, the braking control unit 142 performs braking control of the host vehicle M in accordance with a driving operation by the driver of the host vehicle M (hereinafter, driver operation) or regardless of the operation. For example, the braking control unit 142 sets a deceleration state based on a contact margin value between the host vehicle M and the obstacle, and executes deceleration control based on the set deceleration state. The braking control unit 142 includes, for example, a gradual deceleration control unit 142A and a contact avoidance braking control unit 142B.

[0047] The gradual deceleration control unit 142A performs gradual deceleration control of the host vehicle M when the recognition unit 110 determines that an obstacle (e.g., another vehicle) is present ahead of the host vehicle M. The gradual deceleration control is control (attention control) for alerting the driver to the approach of another vehicle by deceleration, and is different from contact avoidance control for avoiding contact with the obstacle (however, it may result in avoiding contact with the obstacle). For example, when it is determined that an obstacle is present ahead of the host vehicle M, the gradual deceleration control unit 142A derives a target deceleration for the host vehicle M and decelerates the host vehicle M to approach the derived target deceleration without the driver's operation. Furthermore, the gradual deceleration control may be performed when the driving state detection unit 120 detects that the driver is driving absentmindedly, or may be performed when the contact margin value satisfies the operating condition for the gradual deceleration control.

[0048] Furthermore, the slow deceleration control unit 142A may stop the slow deceleration control when the driving state detection unit 120 detects that the driver has operated the accelerator (operated the accelerator pedal 84) at a predetermined value (for example, a predetermined amount) or more during the slow deceleration control. In this way, by determining the driver's intention based on the accelerator operation, it is possible to execute a more appropriate override control (switching to manual driving by the driver) for the slow deceleration control. The predetermined value (predetermined amount) may be changed based on the operation speed of the driver's accelerator operation. For example, the slow deceleration control unit 142A may set the predetermined value smaller when the operation speed is equal to or greater than the predetermined speed than when the operation speed is less than the predetermined speed, and set the predetermined value larger when the operation speed is less than the predetermined speed than when the operation speed is equal to or greater than the predetermined speed. Furthermore, the slow deceleration control unit 142A may change the predetermined value according to the target deceleration, for example, and set the predetermined value larger as the target deceleration increases. This allows for more appropriate override determination to be achieved according to the driver's driving situation and the surrounding conditions of the host vehicle M.

[0049] The contact avoidance braking control unit 142B performs emergency braking control to avoid contact between the host vehicle M and an obstacle. For example, when it is determined that the host vehicle M may come into contact with an obstacle based on the surrounding conditions recognized by the recognition unit 110, the contact avoidance braking control unit 142B performs braking control (deceleration control) to avoid contact. The braking control performed by the contact avoidance braking control unit 142B includes, for example, a Collision Mitigation Brake System (CMBS) control that assists in contact avoidance or damage mitigation. The braking control performed by the contact avoidance braking control unit 142B may be performed, for example, after gradual deceleration control, or may be performed when the contact margin value satisfies the operating conditions for the braking control.

[0050] The steering control unit 144 controls the steering of the host vehicle M. The steering control unit 144 includes, for example, a centering steering control unit 144A and a contact avoidance steering control unit 144B. When the recognition unit 110 determines that an obstacle exists ahead of the host vehicle M, the centering steering control unit 144A executes steering control (centering steering control) to move the host vehicle M toward the center of the driving lane. This steering control is not intended to avoid contact with the obstacle, but rather to make the driver aware of the obstacle ahead and encourage attention by the vehicle behavior of moving laterally (moving in the road width direction) toward the center (however, it may result in avoiding contact with the obstacle). This steering control can make the driver aware of the obstacle ahead early and contribute to driving to avoid contact. Note that the centering steering control may be executed when the driving state detection unit 120 detects that the driver is driving absentmindedly, or may be executed when the contact margin value satisfies the operating condition of the steering control. Furthermore, the above-described gradual deceleration control and centering steering control may be executed separately, or may be executed simultaneously at the same timing (for example, at the attention-attraction control stage).

[0051] The contact avoidance steering control unit 144B performs steering control of the host vehicle M to avoid contact between the host vehicle M and an obstacle. For example, when avoidance is possible within the driving lane of the host vehicle M, the contact avoidance steering control unit 144B performs a steering operation to move the host vehicle M in a direction that will not contact the obstacle within a range that does not deviate from the same lane, without relying on a steering operation by the driver. Furthermore, the contact avoidance steering control unit 144B may perform steering control of the host vehicle M so that the behavior of the host vehicle M after the avoidance operation is stable after the driver's steering operation causes the host vehicle M to cross a dividing line that separates the driving lane and perform an avoidance operation against the obstacle. The steering control performed by the contact avoidance steering control unit 144B may be performed, for example, after a centering steering control, or may be performed when the contact margin value satisfies the operating condition of the steering control.

[0052] The control unit 140 may execute control other than the vehicle control described above. For example, the control unit 140 performs steering control to keep the host vehicle M within the driving lane as LKAS (Lane Keeping Assistance System) control (lane maintenance control). In this case, the control unit 140 controls the steering device 220 to prevent the host vehicle M from deviating from the driving lane, thereby assisting the driver in steering.

[0053] The HMI control unit 150 notifies the occupants (including the driver) of predetermined information via the HMI 30. The predetermined information includes, for example, information related to the traveling of the vehicle M, such as information related to the state of the vehicle M and information related to driving control. The information related to the state of the vehicle M includes, for example, the speed of the vehicle M, engine speed, and shift position. The information related to driving control includes, for example, the type of driving control being executed (e.g., gradual deceleration, centering steering control, contact avoidance braking control, contact avoidance steering control), the reason for operating the driving control, the status of the driving control, and information indicating that the driving control has started or ended. The information related to driving control may also include information regarding a warning or alert to the driver. The predetermined information may also include information related to the current location or destination of the vehicle M, the remaining amount of fuel, and information unrelated to the traveling control of the vehicle M, such as television programs, content (e.g., movies) stored on a storage medium such as a DVD, etc.

[0054] For example, the HMI control unit 150 may generate an image including the above-described predetermined information and display the generated image on the display unit 32 of the HMI 30, or may generate sound indicating the predetermined information and output the generated sound from the speaker 34 of the HMI 30. The timing at which the sound is output may be, for example, when driving control is started or stopped, when a call is received, when the image to be displayed is switched, or when the vehicle M has entered a predetermined state. The HMI control unit 150 may also output information received by the HMI 30 to the control unit 140, etc. The HMI control unit 150 also controls the timing at which the information output by the HMI 30 starts and ends output based on the control content by the control unit 140.

[0055] [Control Unit] Next, details of vehicle control by the control unit 140 will be described. Fig. 2 is a diagram for explaining the content of vehicle control related to contact avoidance. The example of Fig. 2 shows the content of vehicle control when it is determined that there is a possibility of contact based on the time to contact TTC. In the example of Fig. 2, it is assumed that time T1 is the earliest, followed by times T2, T3, T4, and T5 in that order.

[0056] First, at time T1 in Fig. 2, it is assumed that the contact possibility determination unit 130 determines that there is a possibility of contact between the host vehicle M and an obstacle. When it is determined that there is a possibility of contact, the control unit 140 performs attention calling control ((1) in the figure) to call the driver's attention to the surroundings (particularly the traveling direction) based on the time to contact TTC and the detection result of the driving state detection unit 120. The attention calling control and the contact attention warning control described later are controls that are executed, for example, at a stage before performing contact avoidance control between the host vehicle M and an obstacle (e.g., another vehicle).

[0057] FIG. 3 is a diagram for explaining the details of attention-calling control. The example of FIG. 3 shows lanes L1 and L2 that can be traveled in the same direction (X-axis direction in the figure). Lane L1 is demarcated by marking lines LN1 and LN2, and lane L2 is demarcated by marking lines LN2 and LN3. In the example of FIG. 3, the host vehicle M is traveling on lane L1 at a speed VM, and a vehicle (leading vehicle) m1 traveling ahead of the host vehicle M is traveling on lane L1 ahead of the host vehicle M at a speed Vm1. In the following description, the other vehicle m1 is assumed to be an obstacle.

[0058] 3, the control unit 140 performs the attention-calling control when the time to contact TTC (contact margin value) based on the relative position and relative speed between the host vehicle M and another vehicle m1 reaches a time T2 that is equal to or less than a first predetermined value (predetermined time) and the driver is detected as being careless. The time T2 is a value that is set, for example, when the time to contact TTC is between about 3 and 4 seconds, but may be variably set based on the relative speed, relative position, road shape, etc.

[0059] The attention calling control includes, for example, at least one of the slow deceleration control by the slow deceleration control unit 142A and the centering steering control by the centering steering control unit 144A. The slow deceleration control executed in the attention calling control is control in a first deceleration state. The slow deceleration control unit 142A sets a target deceleration (first target deceleration) so that a load (longitudinal G) of a first upper limit deceleration (approximately 0.1 [G]) is applied to the driver in the traveling direction (longitudinal direction). In addition, in the attention calling control (first deceleration state), the slow deceleration control unit 142A may first perform the slow deceleration control at a first deceleration rate (for example, longitudinal G of 0.05 [G]), and then perform the deceleration control at a second deceleration rate (for example, longitudinal G of 0.1 [G]) that is greater than the first deceleration rate. By controlling the deceleration rate to increase in stages in this manner, the burden on occupants such as the driver when the slow deceleration control begins to be executed can be reduced, and the occupants can be prevented from being surprised by the slow deceleration control.

[0060] Furthermore, in the attention-attracting control, the centering steering control unit 144A performs centering steering control to steer the host vehicle M toward the center of the driving lane (lane L1). Details of the centering steering control will be described later. In the example of Fig. 3, the control unit 140 generates a future target trajectory K1 of the host vehicle M corresponding to gradual deceleration and centering steering control, and controls the steering and speed of the host vehicle M so that the host vehicle M travels along the target trajectory K1.

[0061] At time T2, the HMI control unit 150 may generate an image (an example of information) indicating that at least one of the gradual deceleration control and the centering steering control of the driver's attention alert control has started, or an image indicating the reason for the operation, and notify the driver by displaying the generated image on the display unit 32 (however, no audio output is provided). This makes it possible to more clearly inform the driver of the approaching obstacle, urging them to pay attention, and to prompt the occupant to take early avoidance action. Furthermore, when the attention alert control has ended, the HMI control unit 150 may generate and output an image indicating the end. Furthermore, when the attention alert control has ended, the HMI control unit 150 may erase the image indicating the start that was being displayed from the display unit 32, instead of displaying the image indicating the end.

[0062] Here, when the activation determination is made using the time to contact TTC, there is a possibility that the attention warning control cannot be performed at an appropriate timing when the relative speed between the host vehicle M and the other vehicle m1 is 0 (zero). Also, there is a possibility that the activation timing will be delayed when the other vehicle m1 decelerates or accelerates. Therefore, when performing the gradual deceleration control or the centering steering control, the control unit 140 may estimate the position of the other vehicle m1 before or after a predetermined time, and make an activation determination of the attention warning control based on the estimated position.

[0063] Returning to Fig. 2, when the time to contact TTC (contact margin value) becomes less than a predetermined value (predetermined time) at time T3 in a state where the driver does not call attention to those around him / her (or perform override control) even after the above-mentioned attention calling control is performed, and the driver is detected as being careless driving, the contact attention warning control ((2) in the figure) is performed. Time T3 is the time when the time to contact TTC becomes approximately 2 seconds, for example.

[0064] FIG. 4 is a diagram for explaining the content of the contact warning control. FIG. 4 shows a situation in which the time to contact TTC becomes 2 seconds without the driver operating the accelerator pedal in the situation shown in FIG. 3. In the contact warning control stage, the gradual deceleration control unit 142A sets a target deceleration (second target deceleration) and executes gradual deceleration control according to the set second target deceleration. Alternatively, a target trajectory K2 for executing the gradual deceleration control may be generated and the host vehicle M may be controlled to travel along the generated target trajectory K2. The gradual deceleration control executed in the contact warning control is control in the second deceleration state. In the second deceleration state, the gradual deceleration control unit 142A sets the target deceleration (second target deceleration) so that a load (longitudinal G) greater than the first upper limit deceleration is applied to the driver in the traveling direction (longitudinal direction) at or below a second upper limit deceleration (approximately 0.2 G). This makes it easier for the driver to more clearly notice that the host vehicle M is approaching another vehicle m1. In this way, deceleration control is performed while increasing the deceleration rate as needed, which creates more time for the driver to notice the other vehicle m1, allowing the driver to drive with ease to avoid contact with the other vehicle m1.

[0065] Here, when deceleration is performed by warning control or contact warning control, the gradual deceleration control unit 142A may adjust the above-mentioned target deceleration or the position at which deceleration control by the target deceleration ends, based on the detection results of the AP sensor 84A, depending on whether or not accelerator operation by the driver of the vehicle M is detected.

[0066] Furthermore, in the contact warning control, in addition to (or instead of) the gradual deceleration control, the centering steering control may be executed by the centering steering control unit 144A as described above. Furthermore, during the contact warning control, the HMI control unit 150 may execute control (alert escalation control) to highlight an image of attention information displayed on the display unit 32 or to output an attention warning to the speaker 34. This makes it possible to more clearly notify the driver of the high possibility of contact while executing the gradual deceleration control or the centering steering control, thereby more clearly urging the driver to pay attention or take a contact avoidance operation. Furthermore, when the contact warning control has ended, the HMI control unit 150 may generate and output an image or sound indicating the end. Furthermore, when the contact warning control has ended, the HMI control unit 150 may stop outputting an image or sound indicating the start, instead of outputting an image or sound indicating the end.

[0067] Returning to FIG. 2, after the execution of the contact attention warning control, at time T4 when it is determined that automatic avoidance is possible within the driving lane, the steering control unit 144 executes automatic steering avoidance control ((3) shown in FIG. 2). FIG. 5 is a diagram for explaining the content of the automatic steering avoidance control. The example of FIG. 5 is, for example, control when the driver does not operate the accelerator after the execution of the contact attention warning control. In this case, if an avoidance space exists within the driving lane, the contact avoidance steering control unit 144B generates a target trajectory K3 for traveling through the avoidance space based on the area of ​​the driving lane and the position of the other vehicle m1, and executes steering control (speed control as necessary) so that the host vehicle M travels along the generated target trajectory K3. Furthermore, the contact avoidance steering control unit 144B may perform acceleration / deceleration control in addition to steering control. Furthermore, during the automatic steering avoidance control, the HMI control unit 150 may continue to execute the above-mentioned warning escalation control. As a result, when steering avoidance is possible with highly safe control, more appropriate vehicle control can be achieved by executing automatic steering control.

[0068] At this timing, the contact avoidance braking control unit 142B may execute the CMBS control in parallel. When the CMBS control is executed, the above-mentioned automatic steering avoidance control and the contact avoidance steering control described later do not need to be executed.

[0069] 2, at time T5 when the driver operates the steering wheel 82 (detects the driver steering trigger) to perform a steering operation in a direction to avoid the other vehicle m1, the contact avoidance steering control unit 144B performs contact avoidance steering control so as to prevent the vehicle from further departing from the adjacent lane (lane L2) adjacent to the driving lane (lane L1) ((4) in FIG. 2). The contact avoidance steering control may be performed after the automatic steering avoidance control or after the contact attention warning control.

[0070] FIG. 6 is a diagram for explaining steering control after a driver steering trigger. In the example of FIG. 6, when there is no space on the lane L1 to avoid contact of the host vehicle M with another vehicle m1 and a driver steering trigger (a steering amount of the steering wheel 82 by the driver equal to or greater than a threshold) is detected, the contact avoidance steering control unit 144B allows the host vehicle M to move from the lane L1 to the adjacent lane L2 and performs steering control of the host vehicle M so that the host vehicle M does not further deviate from the adjacent lane L2. For example, a target trajectory K4 for changing lanes to the lane L2 is generated, and steering assistance is performed so that the position of the host vehicle M approaches the target trajectory K4 through a steering operation by the driver. Furthermore, during contact avoidance steering control, the HMI control unit 150 may continue to perform the above-described warning escalation control. This allows for more appropriate vehicle control after emergency avoidance steering is performed by the driver's steering operation.

[0071] Furthermore, when the time to contact TTC approaches the limit value immediately after the attention-calling control shown in (1) of Fig. 2 and the driver performs a steering operation, the control unit 140 executes contact avoidance steering control (driver steering assist control) ((5) of Fig. 2) to prevent the vehicle from crossing further into the adjacent lane, similar to the control shown in (4) of Fig. 2. In this case, the HMI control unit 150 may perform notification control such as a notification that the steering assist is operating or an alarm.

[0072] In addition, in each of the above-described operation phases of the attention warning, collision warning, automatic steering avoidance, and collision avoidance steering, a condition related to the speed of the host vehicle M may be added to the determination conditions for operation. For example, in the collision avoidance steering control in the automatic steering avoidance and collision avoidance steering (steering assistance), one of the operation start conditions is that the speed VM of the host vehicle M is 40 km / h or higher. Because this control is performed after the attention warning, a collision margin time TTC of approximately 2 seconds is sufficient to allow collision avoidance through the driver's braking operation. Furthermore, the centering steering control in the attention warning and collision warning is performed when the speed VM of the host vehicle M is 30 km / h or higher. Furthermore, in the case of accelerator operation (AP operation), the gradual deceleration control in the attention warning and collision warning is performed when the speed VM of the host vehicle M is 30 km / h or higher. This speed is below the steering avoidance limit speed and is within the range where the CMBS control has a performance margin. Therefore, setting this condition allows for more appropriate driving control. Furthermore, when there is no AP operation, the control is performed when the speed VM of the host vehicle M is 5 km / h or higher. In other words, the speed is set lower when the driver's AP operation is not detected than when the AP operation is detected. This relaxes the conditions for starting the gradual deceleration control when there is no AP operation, making it possible to perform the gradual deceleration control in various situations, including careless driving in traffic jams, and more safely avoiding contact between the host vehicle M and another vehicle m1.

[0073] [About override control] Controls (gradual deceleration control, centering steering control) being executed during the above-mentioned attention call or collision warning may be stopped midway through the control, for example, by a predetermined operation of the driving operator 80 by the driver. For example, if the driver operates the accelerator pedal 84 to accelerate the host vehicle M while the gradual deceleration control is being executed and the amount of accelerator operation is equal to or greater than a first predetermined amount, the gradual deceleration control unit 142A will stop the gradual deceleration control. Alternatively, the gradual deceleration control unit 142A may stop the gradual deceleration control if the accelerator operation speed is equal to or greater than a predetermined speed, instead of the accelerator operation amount.

[0074] Furthermore, if the driver operates the steering wheel 82 while the centering steering control is being executed and the amount of steering operation (torque amount (steer torque) of the steering wheel 82) is equal to or greater than a second predetermined amount, the centering steering control unit 144A stops the centering steering control. The second predetermined amount may be varied depending on whether the steering direction by the driver's operation is forward or reverse to the steering by the centering steering control. The forward direction means that the steering direction by the driver's operation and the steering direction by the centering steering control are the same direction, and the reverse direction means that the steering direction by the driver's operation and the steering direction by the centering steering control are opposite directions. In this way, by making an override determination after taking into account the driver's intention from the steering direction of the steering wheel 82, more appropriate override control can be performed during the centering steering control.

[0075] [Centering steering control] Next, centering steering control in the warning and collision warning of the embodiment will be described. Note that the following describes several examples of the centering steering control.

[0076] (First Example) Fig. 7 is a diagram showing a first embodiment of centering steering control. The example in Fig. 7 shows the host vehicle M traveling on a lane L1 defined by marking lines LN1 and LN2, and another vehicle m1, which is a preceding vehicle. For example, when approaching the other vehicle m1, the centering steering control unit 144A generates a target trajectory K5 for positioning the host vehicle M at the center CL1 of the lane, and performs steering control so that the host vehicle M travels along the generated target trajectory K5.

[0077] In this way, by steering the host vehicle M to the lane center CL1, if the driver is unaware of another vehicle m1 ahead, the change in the lateral behavior of the host vehicle M (in the width direction of the traveling lane) can make the other vehicle m1 more likely to notice the other vehicle m1, which can contribute to avoiding contact between the host vehicle M and the other vehicle m1. Note that the steering control in the attention alert control is a behavior intended to prompt the driver to monitor the surroundings, and is therefore different from the steering control for the host vehicle M to avoid the other vehicle m1. However, in the steering control in the first embodiment, the host vehicle M is ultimately steered in a direction away from the other vehicle m1, making it easier for the driver to perform subsequent avoidance driving.

[0078] (Second Example) FIG. 8 is a diagram illustrating a second embodiment of centering steering control. The example in FIG. 8 illustrates a case where another vehicle m1 is located near the lane center CL1 as viewed from the host vehicle M, or on the opposite side of the lane center CL1 from the host vehicle M. The opposite side refers to, for example, the side of one of the marking lines LN1 and LN2 that is farther from the host vehicle M. The opposite side refers to a position within the same lane that is outside the lane center CL1 as viewed from the host vehicle M. In this case, the centering steering control unit 144A does not perform steering control to move the host vehicle M to the lane center CL1. In this case, the control unit 140 may generate a target trajectory K6 for traveling along the marking line LN2 that is closer to the host vehicle M, of the two marking lines LN1 and LN2 that define the lane L1 (more specifically, in a state closer to the marking line LN2 than the center of the lane L1), and control the host vehicle to travel along the generated target trajectory K6. Furthermore, if the host vehicle M is traveling closer to the lane marking LN2 than the lane center CL1 even before the centering steering control is executed, the control unit 140 maintains (continues) this traveling. In this case, the control unit 140 may execute LKAS control to prevent the host vehicle M from deviating from the traveling lane. Furthermore, when steering control to move the host vehicle M to the center of the traveling lane is not executed as in the second embodiment, the control unit 140 may execute deceleration control of the host vehicle M (for example, gradual deceleration control).

[0079] (Third Example) 9 is a diagram showing a third embodiment of centering steering control. As shown in FIG. 9, in the third embodiment, regardless of the position of another vehicle m1 on the lane L1 (near the center of the lane, near each dividing line that divides the lane L1), if the host vehicle M is present within the lane center error range, the centering steering control unit 144A generates a target trajectory K7 for moving the host vehicle M to the lane center CL1, and performs steering control so that the host vehicle M travels on the generated target trajectory K7. The lane center error range will be described later. In this way, the driver can be made aware of the presence of a preceding vehicle by the behavior of the lateral movement of the host vehicle M (movement in the road width direction, movement in the Y-axis direction in the figure).

[0080] (Fourth Example) FIG. 10 is a diagram showing a fourth embodiment of centering steering control. In the fourth embodiment, when another vehicle m1 is present within a predetermined range (lateral position error range) relative to the host vehicle M in the width direction of the driving lane, steering control is executed to move the host vehicle M toward the center of the driving lane. The lateral position error range will be described later. As shown in FIG. 10, in the fourth embodiment, when the lateral positions of the host vehicle M and the other vehicle m1 are close (within the lateral position error range), the centering steering control unit 144A generates a target trajectory K8 so that the host vehicle M moves toward the lane center CL1, and controls the steering, etc. of the host vehicle M so that the host vehicle M travels along the generated target trajectory K8.

[0081] In the fourth embodiment, positioning the host vehicle M in the lane center CL1 results in steering in a direction approaching the other vehicle m1, but the steering control for warning the driver is intended to make the driver aware of the other vehicle, and is different from steering control for avoiding contact with the other vehicle m1. By performing this control, the host vehicle M is positioned in the center of the lane L1 at the time the driver is made aware of the other vehicle, so that in subsequent manual driving, it is possible to not only decelerate the host vehicle M but also select either the left or right direction to make steering easier.

[0082] Here, the lane center error range and lateral position error range will be described. FIG. 11 is a diagram for explaining the lane center error range and lateral position error range. The example of FIG. 11 shows the relationship between the rear end projection plane of an object such as another vehicle and the lateral position of the host vehicle M on the road. The lane center error range is set, for example, such that the lateral distance W1 between the center (center) CM of the host vehicle M and the lane center CL1 is approximately 0.3 to 0.5 m to the left and right of the lane center CL1. This is because, in a typical lane, the host vehicle M is considered to be located roughly near the lane center CL1 up to a distance W1 of approximately 0.5 m. However, at 0.5 m, the host vehicle M may be closer to either the lane marking LN1 or LN2. Therefore, when the distance W1 is within approximately 0.3 m, the host vehicle M is determined to be located within the lane center error range.

[0083] Furthermore, regarding the lateral position error range between the center CM of the host vehicle M and the center Cm1 of the object, if the lateral distance W2 between the center CM and the center Cm1 is within 0.2 to 0.3 [m], it is determined that the host vehicle M and the object are within the lateral position error range. Here, the behavior of the host vehicle M may fluctuate within a range of ±0.2 [m] during steering control, which also causes errors in the accuracy of external recognition. Therefore, it is considered that there is a range where a lateral deviation of about 0.2 [m] between the host vehicle M and the object cannot be used for determination, and a lower limit of 0.2 [m] is set to determine whether or not the lateral position error range is within the range. Furthermore, if this value is increased, there is a possibility that control will be performed on objects that do not require centering steering control. Therefore, by setting the upper limit to 0.3 [m], a more appropriate determination can be made.

[0084] (Fifth Example) FIG. 12 is a diagram illustrating a fifth embodiment of centering steering control. The fifth embodiment illustrates centering steering control according to the recognition accuracy of the lane of the host vehicle M. In the example of FIG. 12, the host vehicle M is traveling on the lane L1 at a speed VM, and another vehicle m1 is traveling ahead of the host vehicle M in the same lane at a speed Vm1. In addition, in the example of FIG. 12, the host vehicle M is traveling closer to the lane marking LN1 side than the lane center CL1, out of the marking lines LN1 and LN2 that define the lane L1. In the example of FIG. 12, the marking line LN1 drawn in a portion of the area AR1 is difficult to recognize from the camera image due to rubbing, loss, etc.

[0085] In the fifth embodiment, the recognition unit 110 recognizes the surrounding conditions of the host vehicle M. Specifically, the host vehicle M recognizes the position and speed of another vehicle m1, the positions of the marking lines LN1 and LN2, the lane L1 defined by the marking lines LN1 and LN2, etc. The recognition unit 110 also derives the recognition degree of the marking lines LN1 and LN2. It is assumed that the recognition degree of the marking line LN1 within the area AR1 is less than a threshold value.

[0086] In the fifth embodiment, when the recognition unit 110 recognizes that another vehicle m1 is present ahead of the host vehicle M and the conditions for performing the above-described attention-attracting control are satisfied, the control unit 140 executes centering steering control to move at least the host vehicle M to the center of the traveling lane (gentle deceleration control may also be executed). Here, when the recognition unit 110 recognizes at least one of the lane markings LN1 and LN2 less than a threshold value during execution of the centering steering control, the control unit 140 (centering steering control unit 144A) cancels the centering steering control. Here, "canceling" means, for example, not starting the lateral movement of the host vehicle M if the lateral movement has not yet started due to the steering control, or canceling the lateral movement if the lateral movement is in the process of starting.

[0087] If the degree of recognition of the lane marking LN1 decreases (below the threshold), the lane center CL1 cannot be identified. In this case, by terminating the centering steering control, more appropriate vehicle control can be performed according to the surrounding conditions of the vehicle M.

[0088] Note that the behavior of the vehicle M during centering steering control involves a smaller amount of lateral movement (amount of movement in the road width direction or in the Y-axis direction in the figure) than when changing lanes, so if the state in which the recognition degree of the lane markings is below the threshold is short, there is no significant impact on the driving control of the centering steering control. Therefore, the control unit 140 (centering steering control unit 144A) may stop the centering steering control if the state in which the recognition degree is below the threshold continues for a predetermined time or more.

[0089] Furthermore, when both centering steering control and gradual deceleration control are being executed as attention-attention control, the control unit 140 may continue the gradual deceleration control even if the above-described recognition degree falls below the threshold (in other words, if the centering steering control is stopped due to a decrease in recognition accuracy). Because the gradual deceleration control is a change in the behavior of the host vehicle M in the longitudinal direction (front-rear direction), it is less affected by a decrease in the recognition accuracy of the lane markings than the centering steering control, which involves lateral movement. Therefore, even if the recognition accuracy of the lane markings decreases, the gradual deceleration control can be executed, which makes it easier for the driver to notice obstacles ahead, thereby reducing contact with the obstacles ahead.

[0090] In the fifth embodiment, if the recognition accuracy of the lane markings decreases during centering steering control (lateral movement) of the host vehicle M along the target trajectory, the centering steering control unit 144A may adjust the control content according to the situation of the host vehicle M. For example, when the recognition accuracy of the lane markings decreases, if the remaining lateral movement amount set on the target trajectory is less than a predetermined amount, the centering steering control unit 144A performs the centering steering control to the end, and if the remaining lateral movement amount is equal to or greater than the predetermined amount, the centering steering control unit 144A may also perform the centering steering control to the end if the steering angle of the host vehicle M detected by the vehicle sensor 40 is equal to or greater than a threshold, and may also stop the steering control halfway if the steering angle is less than the threshold. This allows for more appropriate driving control to be performed according to the situation of the host vehicle M.

[0091] (Sixth Example) Figure 13 is a diagram showing a sixth embodiment of centering steering control. In the sixth embodiment, compared to the fifth embodiment described above, it is assumed that a part of the area AR2 on the side of the marking line LN2 of the marking lines LN1 and LN2 is difficult to recognize from the camera image due to rubbing or loss of the marking line. The example in Figure 13 also shows a situation in which another vehicle m1 is present on the side of the center CL1 of the lane or on the opposite side.

[0092] In the sixth embodiment, the control unit 140 controls the host vehicle M to travel along the lane marking LN1 when, for example, the recognition degree of the lane marking LN1 closer to the host vehicle M, of the two lane markings LN1 and LN2 that define the lane L1, is equal to or greater than a threshold value, and the recognition degree of the lane marking LN2 farther from the host vehicle M is less than a threshold value. For example, when another vehicle m1 is present on the center or opposite side of the lane L1, the control unit 140 generates a target trajectory K9 for traveling closer to the lane marking closer to the host vehicle M (the lane marking LN1 in the case of FIG. 13), as shown in the second embodiment, and controls the host vehicle M to travel along the generated target trajectory K9. Furthermore, if the host vehicle M has been traveling closer to the lane marking LN1 than the lane center CL1 before the centering steering control was executed, the control unit 140 maintains (continues) the traveling direction. In this case, the control unit 140 may execute LKAS control to prevent the host vehicle M from deviating from the traveling lane. Furthermore, when steering control for moving the host vehicle M to the center of the driving lane is not executed as in the sixth embodiment, the control unit 140 may execute deceleration control of the host vehicle M (for example, gradual deceleration control).

[0093] As a result, if the recognition accuracy of the marking line LN1 that is closer to the vehicle M among the marking lines that define the vehicle's driving lane L1 is not low (the recognition degree is equal to or greater than the threshold), driving control can be continued to follow the marking line even if the recognition accuracy of the more distant marking line is low (the recognition degree is less than the threshold). Note that, as shown in FIG. 12, if the recognition accuracy of the marking line LN1 that is closer to the vehicle M is low, centering steering control is stopped even if the recognition accuracy of the more distant marking line LN2 is not low. This makes it possible to suppress lateral movement that is greater than that caused by centering steering in order to move closer to the more distant marking line LN2.

[0094] For example, when the control unit 140 starts at least one of the centering steering control and the gentle deceleration steering control, the HMI control unit 150 outputs information (such as an image) indicating the start of the control from the HMI 30. Furthermore, when the ongoing control ends, the HMI control unit 150 outputs information indicating the end from the HMI 30. Furthermore, as shown in the fifth embodiment, even if the recognition unit 110 detects a recognition degree of the lane markings LN1 and LN2 that define the lane L1 on which the host vehicle M is traveling and the centering steering control is stopped because the recognition degree is less than a threshold during the execution of the centering steering control, the HMI control unit 150 may not notify the user that the centering steering control has ended if the gentle deceleration control is still ongoing. This prevents the driver from becoming confused when the gentle deceleration control is terminated due to the termination of the steering control. Furthermore, the driver can concentrate on avoiding obstacles ahead without being distracted by the termination notification or the like.

[0095] [Processing flow] Fig. 14 is a flowchart showing an example of processing executed by the driving assistance device 100 in the embodiment. In the example of Fig. 14, the processing executed by the driving assistance device 100 will be mainly described, focusing on processing related to centering steering control. Furthermore, the following processing may be repeatedly executed at a predetermined cycle or at a predetermined timing.

[0096] In the example of FIG. 14, the recognition unit 110 recognizes the surrounding conditions of the host vehicle M (step S100). Next, the driving state detection unit 120 detects the driving state of an occupant (driver) of the host vehicle M (step S110). Next, the driving state detection unit 120 determines whether the driver's driving state is absentminded driving or not (step S120). If it is determined that the driver is driving absentmindedly, the contact possibility determination unit 130 determines whether another vehicle m1 (an example of an obstacle) is present ahead of the host vehicle M (step S130). If it is determined that another vehicle m1 is present ahead, a contact margin value between the host vehicle M and the other vehicle m1 is derived (step S140).

[0097] Next, the control unit 140 determines whether the contact margin value satisfies the activation condition for the centering steering control (in other words, the execution condition for the attention calling control) (step S150). If it is determined that the activation condition is satisfied, the control unit 140 executes the centering steering control process (step S160). The process of step S160 will be described in detail later. This ends the process of this flowchart. Furthermore, if it is determined in the process of step S120 that the driver is not driving aimlessly, if it is determined in the process of step S130 that there is no other vehicle ahead, or if it is determined in the process of step S150 that the contact margin value does not satisfy the activation condition for the centering steering control, the process of this flowchart ends. Note that in the embodiment, in addition to (or instead of) the processes of steps S150 and S160, the control unit 140 may determine whether the contact margin value satisfies the activation condition for the gradual deceleration control, and execute the gradual deceleration control if it is determined that the activation condition for the gradual deceleration control is satisfied.

[0098] FIG. 15 is a flowchart showing an example of a centering steering control process. The process in FIG. 15 corresponds to the process in step S160. In the example in FIG. 15, the control unit 140 derives the recognition degree of two lane markings that demarcate the lane of the host vehicle M (step S161), and determines whether the derived recognition degree of the two lane markings is equal to or greater than a threshold (step S162). If it is determined that the recognition degree of the two lane markings is equal to or greater than the threshold, the control unit 140 determines whether the other vehicle m1 is located closer to the center of the lane of the host vehicle M or on the opposite side (step S163). If it is determined that the other vehicle m1 is not located closer to the center of the lane of the host vehicle M or on the opposite side, the control unit 140 executes steering control to move the host vehicle M to the center of the lane of the host vehicle M (step S164).

[0099] Furthermore, if it is determined in the processing of step S163 that the other vehicle m1 is located closer to the center of the lane or on the opposite side of the lane than the host vehicle M, the control unit 140 executes control to cause the host vehicle M to travel along the lane marking closer to the host vehicle M (step S165). In this case, the control unit 140 does not execute control to move the host vehicle M to the center of the lane.

[0100] Furthermore, if it is determined in the processing of step S162 that the recognition degrees of the two lane markings are not equal to or greater than the threshold (are less than the threshold), the control unit 140 determines whether the recognition degree of the lane marking closer to the host vehicle M is equal to or greater than the threshold (step S166). If the recognition degree is equal to or greater than the threshold, the control unit 140 performs the processing of step S165. Furthermore, if it is determined in the processing of step S166 that the recognition degree is not equal to or greater than the threshold, the control unit 140 suspends steering control (step S167). Next, the control unit 140 determines whether gradual deceleration control is being executed (step S168). If it is determined that gradual deceleration control is being executed, the control unit 140 continues the gradual deceleration control until a condition for terminating the gradual deceleration control is met (step S169). This ends the processing of this flowchart. Furthermore, if it is determined in the processing of step S166 that gradual deceleration control is not being executed, the processing of this flowchart ends.

[0101] [Variations] In the attention warning control of the embodiment, the control unit 140 may select and execute either the gradual deceleration control or the centering steering control depending on, for example, road conditions and the positions and number of surrounding vehicles. For example, if it is determined that the driver is driving absentmindedly, the control unit 140 may execute the gradual deceleration control and the centering steering control, and if it is determined that the driver is not driving absentmindedly, the control unit 140 may execute either the gradual deceleration control or the centering steering control. This allows for more appropriate vehicle control depending on the driver's state.

[0102] In addition, in the above-described embodiment, the gradual deceleration control and the centering steering control may be performed without determining whether the driver is driving absentmindedly. The numerical values ​​shown in the above-described embodiment are merely examples, and may be adjusted as appropriate depending on the road conditions (shape, number of lanes, road type), the driver's driving conditions (degree of absentmindedness), the vehicle conditions (speed, vehicle type, shape, number of passengers), etc.

[0103] Furthermore, in the embodiment, if there is an area where the recognition accuracy of the lane markings in the camera image is low, the control unit 140 may interpolate the lane markings in that area using map information. In this case, the control unit 140 determines whether the lane markings in the area recognized by the camera image (and in the area near the area with low recognition accuracy) match the lane markings recognized by the map information, and performs interpolation only if it is determined that they match (if the degree of deviation of the lane markings is less than a threshold or the match rate is equal to or greater than a threshold). In this way, even if there is an area where the recognition accuracy of the lane markings is low, the lane markings are interpolated using the map information, making it possible to prevent the centering steering control from being suspended.

[0104] As described above, the driving assistance device 100 (an example of a vehicle control device) of the embodiment includes a recognition unit 110 that recognizes the surrounding conditions of the host vehicle M, and a control unit 140 that controls one or both of the steering and acceleration / deceleration of the host vehicle M when an obstacle is present in front of the host vehicle M based on the recognition result of the recognition unit 110.When it is determined that an obstacle is present in front of the host vehicle M, the control unit 140 performs steering control to move at least the host vehicle M to the center of the driving lane, and when the recognition unit 110 recognizes the degree to which the dividing line that separates the driving lane in which the host vehicle is traveling is less than a threshold value during the execution of steering control, the control unit 140 stops steering control, thereby enabling more appropriate vehicle control to be performed according to the surrounding conditions of the vehicle at a stage before performing contact avoidance control between the vehicle and the obstacle.

[0105] Furthermore, according to the embodiment, when approaching an obstacle ahead, steering to the center of the lane makes it easier for the driver to notice the obstacle ahead if the driver has not noticed it, which contributes to avoiding contact with the obstacle ahead. Furthermore, according to the embodiment, a more appropriate determination to discontinue centering steering control can be made based on the recognition accuracy of the marking lines that divide the driving lane. Furthermore, according to the embodiment, even if the recognition accuracy of the marking line farther from the vehicle M of two marking lines that divide the driving lane has decreased (when the recognition degree is below a threshold), if the recognition accuracy of the marking line closer to the vehicle M is not low (when the recognition degree is equal to or greater than the threshold), steering control to travel along the marking line without steering to the center of the lane can be continued, thereby improving the continuity of steering control.

[0106] Furthermore, according to the embodiment, when deceleration control is being executed together with steering control to move the host vehicle M toward the center of the lane, the deceleration control is continued even if the recognition accuracy of the lane markings decreases, thereby making it easier for the driver to notice the obstacle ahead even if the driver has not noticed the obstacle ahead. Furthermore, according to the embodiment, even if the steering control is stopped due to a decrease in the recognition accuracy of the lane markings, if the deceleration control is continuing, a notification indicating that the steering control has been stopped is not given, thereby suppressing confusion among the occupants due to the notification, and allowing the driver to concentrate on avoiding the obstacle ahead without being distracted by the notification, etc.

[0107] The above-described embodiment can be expressed as follows. a storage medium for storing computer-readable instructions; a processor connected to the storage medium; The processor executes the computer-readable instructions to: Recognizes the surrounding situation of the vehicle, Based on the result of the recognition, when an obstacle is present ahead of the host vehicle, a driving control is executed to control one or both of steering and acceleration / deceleration of the host vehicle; the driving control includes, when it is determined that an obstacle exists ahead of the host vehicle, executing steering control to move the host vehicle to the center of a traveling lane; When the steering control is being performed, if a recognition degree of a lane marking that defines a lane in which the host vehicle is traveling is less than a threshold, the steering control is stopped. Vehicle control device.

[0108] 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]

[0109] 10...camera, 12...radar device, 14...LIDAR, 16...object recognition device, 20...communication device, 30...HMI, 40...vehicle sensor, 50...navigation device, 60...MPU, 70...driver monitor camera, 80...driving operator, 82...steering wheel, 84...accelerator pedal, 86...brake pedal, 100...driving assistance device, 110...recognition unit, 120...driving state detection unit, 130...contact possibility determination unit, 140...control unit, 142...braking control unit, 144...steering control unit, 150...HMI control unit, 160...memory unit, 200...driving force output device, 210...brake device, 220...steering device, M...host vehicle

Claims

1. a recognition unit that recognizes the surrounding conditions of the vehicle; a control unit that controls at least steering of the vehicle among steering and acceleration / deceleration of the vehicle when an obstacle is present ahead of the vehicle based on a recognition result of the recognition unit, The control unit When it is determined that an obstacle exists ahead of the host vehicle, a steering control is executed to move the host vehicle to the center of the traveling lane, When the steering control is being performed, if a degree of recognition of a lane marking that demarcates a lane in which the host vehicle is traveling by the recognition unit is less than a threshold value, the steering control is stopped. Vehicle control device.

2. the control unit causes the vehicle to travel along the lane marking closer to the vehicle when the recognition degree of the lane marking closer to the vehicle is equal to or greater than a threshold and the recognition degree of the lane marking farther from the vehicle is less than a threshold, The vehicle control device according to claim 1 .

3. The control unit When an obstacle is present ahead of the host vehicle, a deceleration control is executed to decelerate the host vehicle; When the deceleration control is being performed, the deceleration control is continued even if the degree of recognition of a lane marking that demarcates the lane in which the host vehicle is traveling by the recognition unit becomes less than a threshold value. The vehicle control device according to claim 1 .

4. a notification control unit that, when at least one of the steering control and the deceleration control is completed by the control unit, issues a notification indicating that the control has been completed; The notification control unit does not issue a notification indicating that the steering control has ended if the deceleration control is continued even when the degree of recognition of a lane marking by the recognition unit that demarcates the lane in which the vehicle is traveling becomes less than a threshold value during execution of the steering control and the steering control is stopped. The vehicle control device according to claim 3 .

5. The control unit stops the steering control when a state in which the recognition degree is less than a threshold value continues for a predetermined time or more. The vehicle control device according to claim 1 .

6. The computer Recognizes the surrounding situation of the vehicle, Based on the recognition result, when an obstacle is present ahead of the host vehicle, a driving control is executed to control at least the steering of the host vehicle among the steering and acceleration / deceleration of the host vehicle; the driving control includes, when it is determined that an obstacle exists ahead of the host vehicle, executing steering control to move the host vehicle to the center of a traveling lane; When the steering control is being performed, if a recognition degree of a lane marking that defines a lane in which the host vehicle is traveling is less than a threshold, the steering control is stopped. Vehicle control method.

7. On the computer, Recognize the surrounding situation of your vehicle, When an obstacle is present ahead of the host vehicle based on the recognition result, a driving control is executed to control at least the steering of the host vehicle among the steering and acceleration / deceleration of the host vehicle; the driving control includes, when it is determined that an obstacle exists ahead of the host vehicle, executing steering control to move the host vehicle to the center of a traveling lane; When the steering control is being performed, if a recognition degree of a lane marking that defines a lane in which the host vehicle is traveling is less than a threshold, the steering control is stopped. program.

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