Vehicle control device, vehicle control method, and program

Abstract

A vehicle control device according to an embodiment comprises: a recognition unit that recognizes the situation around a host vehicle; a vehicle state acquisition unit that acquires the state of the host vehicle; and a position determination unit that, on the basis of the surrounding situation and the state of the host vehicle, determines a merging start position at which the host vehicle will start merging from a merging lane to a main lane in a merging section. The position determination unit sets a provisional merging start position on the basis of the shape of the merging section, derives the relative position between the position of another vehicle present around the host vehicle and the provisional merging start position when a prediction time until the host vehicle reaches the set provisional merging start position elapses, and determines the merging start position by applying a preset determination rule in accordance with the derived relative position.

Description

Vehicle control device, vehicle control method, and program

[0001] This application claims priority to Japanese Patent Application No. 2023-210812, filed on December 14, 2023, the contents of which are incorporated herein by reference.

[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 into autonomous driving technology to further improve traffic safety and convenience. In this regard, a technology has recently been known that calculates a state value for each of multiple state paths defined by selecting from multiple candidates the amount of activity occurring between a start point and a target point in a state space centered on multiple elements related to vehicle movement, and determines the future speed transition of a vehicle according to the state path with the highest calculated state value (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2022-107296

[0004] Incidentally, when merging from a merging lane onto a main lane, automated driving technology executes merging control according to the position and speed of surrounding vehicles, but no consideration has been given to determining the merging start position to achieve smooth merging with speed control. Therefore, there has been an issue in that it may not be possible to execute an appropriate merging.

[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 determine a more appropriate merging start position and thereby execute more appropriate merging of the vehicle, thereby contributing to the development of a sustainable transportation system.

[0006] The present invention provides a vehicle control device, a vehicle control method, and a program, each configured as follows: (1): A vehicle control device according to one aspect of the present invention includes: a recognition unit that recognizes a surrounding situation of a host vehicle; a vehicle state acquisition unit that acquires a state of the host vehicle; and a position determination unit that determines a merging start position in a merging section where the host vehicle will start merging from a merging lane onto a main lane based on the surrounding situation and the state of the host vehicle, wherein the position determination unit sets a tentative merging start position based on a shape of the merging section, derives a relative position between the tentative merging start position and positions of other vehicles present in the vicinity of the host vehicle when a predicted time until the host vehicle reaches the set tentative merging start position has elapsed, and determines the merging start position by applying a predetermined determination rule in accordance with the derived relative position.

[0007] (2): In the above aspect (1), a driving control unit is further provided that, when the vehicle reaches the merging start position determined by the position determination unit, controls at least the steering of the vehicle, among the steering and speed of the vehicle, to cause the vehicle to merge from the merging lane onto the main lane.

[0008] (3): In the aspect (1) above, the position determination unit determines the merging start position to be a position closer to the tentative merging start position from the vehicle's perspective when the position of the other vehicle relative to the tentative merging start position is in front of or behind the tentative merging start position and the distance between the vehicle and the other vehicle is already greater than a predetermined distance when the vehicle reaches the start point of the merging section.

[0009] (4): In the aspect (1) above, the position determination unit determines the tentative merging start position as the merging start position when the position of the other vehicle relative to the tentative merging start position is in front of or behind the tentative merging start position, and when the vehicle reaches the start point of the merging section, the distance between the vehicle and the other vehicle is less than a predetermined distance.

[0010] (5): In the aspect (1) above, when the tentative merging start position is between a plurality of other vehicles, the position determination unit determines the merging start position based on the difference between the relative distance from the other vehicle ahead of the vehicle to the vehicle, which is based on the speed of the vehicle and the speed of the other vehicle ahead of the tentative merging start position, and the relative distance from the other vehicle behind the vehicle to the vehicle, which is based on the speed of the vehicle and the speed of the other vehicle behind the tentative merging start position.

[0011] (6): In the aspect (1) above, after determining the merging start position, if it is determined that it is unsafe to start merging at the merging start position before the vehicle reaches the merging start position, the position determination unit changes the merging start position to a position farther away from the current position of the vehicle.

[0012] (7): In the above aspect (1), a notification control unit is further provided that notifies the occupant of the vehicle of the merging start position in a notification manner according to the distance between the determined merging start position and the vehicle.

[0013] (8) In the aspect (7) above, the notification control unit may emphasize the merging start position as the host vehicle approaches the merging start position.

[0014] (9): A vehicle control method according to one aspect of the present invention is a vehicle control method in which a computer recognizes a surrounding situation of a host vehicle, acquires a state of the host vehicle, determines a merging start position at which the host vehicle will start merging from a merging lane onto a main lane in a merging section based on the surrounding situation and the state of the host vehicle, sets a tentative merging start position based on the shape of the merging section, derives a relative position between the positions of other vehicles present in the vicinity of the host vehicle and the tentative merging start position when a predicted time until the host vehicle reaches the set tentative merging start position has elapsed, and determines the merging start position by applying a predetermined decision rule according to the derived relative position.

[0015] (10): A program according to one aspect of the present invention causes a computer to recognize a surrounding situation of a host vehicle, acquire a state of the host vehicle, determine a merging start position in a merging section where the host vehicle will start merging from a merging lane onto a main lane based on the surrounding situation and the state of the host vehicle, set a tentative merging start position based on the shape of the merging section, derive a relative position between the positions of other vehicles present in the vicinity of the host vehicle and the tentative merging start position when a predicted time has elapsed until the host vehicle reaches the set tentative merging start position, and determine the merging start position by applying a predetermined decision rule based on the derived relative position.

[0016] According to the above aspects (1) to (10), a more appropriate merging start position can be determined, thereby enabling the host vehicle to merge more appropriately.

[0017] 1 is a diagram showing an example of the configuration of a vehicle system 1 equipped with a vehicle control device according to a first embodiment. It is a functional configuration diagram of a first control unit 120 and a second control unit 160. It is a diagram for explaining the processing when a host vehicle M merges from a merging lane onto a main lane. It is a diagram showing an example of an optimized position determination processing. It is a diagram showing a scene in which the merging start position is changed to an earlier position than a tentative merging start position P1. It is a flowchart showing an example of processing executed by an autonomous driving control device 100. It is a flowchart showing an example of a position determination processing. It is a flowchart showing an example of a merging start position determination processing based on a relative position. It is a diagram showing an example of the configuration of a vehicle system 2 equipped with a vehicle control device according to a second embodiment. It is a diagram for explaining a notification mode of a merging start position in the second embodiment. It is a flowchart showing an example of processing executed by a vehicle control device of the second embodiment.

[0018] Hereinafter, embodiments of a vehicle control device, a vehicle control method, and a program according to the present invention will be described with reference to the drawings.

[0019] [First Embodiment] In the first embodiment, an embodiment in which a vehicle control device is applied to an autonomous vehicle will be described. Autonomous driving refers to, for example, automatically controlling one or both of the steering and acceleration / deceleration of a vehicle to perform driving control. Vehicle driving control may include various driving assistance systems, such as a Lane Keeping Assistance System (LKAS), Adaptive Cruise Control (ACC), and Auto Lane Changing (ALC). Some or all of the driving of an autonomous vehicle may be controlled manually by an occupant (driver). Note that, although the following description will be given of a case in which a law stipulating left-hand traffic applies, if a law stipulating right-hand traffic applies, the terms left and right may be reversed.

[0020] 1 is a diagram showing an example of the configuration of a vehicle system 1 equipped with a vehicle control device according to a first embodiment. The vehicle (hereinafter referred to as the subject vehicle M) equipped with the vehicle system 1 is, for example, a two-wheeled, three-wheeled, or four-wheeled vehicle, and its drive source is an internal combustion engine such as a diesel engine or a gasoline engine, an electric motor, or a combination thereof. The electric motor operates using power generated by a generator connected to the internal combustion engine, or discharge power from a secondary battery or a fuel cell.

[0021] The vehicle system 1 includes, for example, a camera 10, a radar device 12, a light detection and ranging (LIDAR) device 14, an object recognition device 16, a communication device 20, a human machine interface (HMI) 30, vehicle sensors 40, a navigation device 50, a map positioning unit (MPU) 60, a driving operator 80, an automatic driving control device 100, a driving force output device 200, a braking device 210, and a steering device 220. These devices and equipment are connected to each other via multiplexed communication lines such as a controller area network (CAN) 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 additional components may be added. The automatic driving control device 100 is an example of a "vehicle control device." A combination of the camera 10, the radar device 12, the LIDAR 14, and the object recognition device 16 is an example of a "detection device DD." The HMI 30 is an example of a "notification unit."

[0022] The camera 10 is 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 of the host 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. When capturing an image of the rear of the host vehicle M, the camera 10 is attached to the top of the rear windshield, the back door, or the like. When capturing an image of the sides and rear of the host vehicle M, the camera 10 is attached to a door mirror, or the like. The camera 10 periodically and repeatedly captures images of the surroundings of the host vehicle M, for example. The camera 10 may be a stereo camera.

[0023] The radar device 12 emits radio waves such as millimeter waves around the vehicle M and detects radio waves reflected by surrounding objects (reflected waves) to detect at least the position (distance and direction) of the objects. The radar device 12 is attached to any location on the vehicle M. The radar device 12 may detect the position and speed of the objects using an FM-CW (Frequency Modulated Continuous Wave) method.

[0024] The LIDAR 14 irradiates the surroundings of the vehicle M with light (or electromagnetic waves with a wavelength similar to that of 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.

[0025] The object recognition device 16 performs sensor fusion processing on the detection results from some or all of the detection devices DD (camera 10, radar device 12, and LIDAR 14) to recognize the position, type, speed, etc. of the object. The object recognition device 16 outputs the recognition results to the autonomous driving control device 100. The object recognition device 16 may output the detection results from the camera 10, radar device 12, and LIDAR 14 directly to the autonomous driving control device 100. In this case, the object recognition device 16 may be omitted from the vehicle system 1.

[0026] 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.

[0027] The HMI 30 presents various information to occupants of the vehicle M and accepts input operations from the user. The occupants include, for example, the driver of the vehicle M and passengers. The HMI 30 includes, for example, a display unit 32, a speaker 34, and a vibration unit 36. The HMI 30 may also include a buzzer, a touch panel, a switch, keys, a microphone, etc.

[0028] The display unit 32 is, for example, located below the front windshield and provided on a dashboard in front of the driver's seat and passenger seat in the vehicle cabin. Alternatively, the display unit 32 may be provided near the front of the driver's seat (the seat closest to the steering wheel) in a position where the driver can see it through the gap in the steering wheel or over the steering wheel.

[0029] The display unit 32 is, for example, any of various display devices such as an LCD (Liquid Crystal Display) or an organic EL (Electro Luminescence) display. The display unit 32 displays an image output by an HMI control unit 170 (described later). The display unit 32 may also be a touch panel that receives operations by the occupant on a screen. The display unit 32 may also function as an instrument panel (meter display) that displays instruments such as a speedometer and a tachometer. The display unit 32 may also be a HUD (Head Up Display). An HUD projects an image onto a portion of the front windshield in front of the driver's seat, allowing the occupant seated in the driver's seat to view a virtual image. The display unit 32 displays an image (still image or moving image) under the control of the HMI control unit 170 (described later).

[0030] At least one speaker 34 is installed in the vehicle cabin. The speaker 34 outputs voice, warning sounds, etc., under the control of, for example, the HMI control unit 170. The vibration unit 36 ​​vibrates one or both of the seats and the steering wheel of the occupants of the vehicle M under the control of, for example, the HMI control unit 170, to notify the occupants through their haptic (tactile) senses.

[0031] The vehicle sensors 40 include 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 angular velocity around a vertical axis, and a direction sensor that detects the orientation of the host vehicle M. The vehicle sensors 40 may also include a position sensor that acquires 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.

[0032] 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 determines the position of the vehicle M based on signals received from GNSS satellites. The position of the vehicle M may be determined or supplemented by an inertial navigation system (INS) that uses the output of the vehicle sensors 40. The navigation HMI 52 includes a display device, a speaker, a touch panel, keys, etc. The navigation HMI 52 may share some or all of the components with the HMI 30 described above. The route determination unit 53 determines a route (hereinafter, a map route) from the position of the vehicle M determined by the GNSS receiver 51 (or any input position) to a destination input by the occupant using the navigation HMI 52, for example, by referring to the first map information 54. The first map information 54 is information that represents road shapes using, for example, links indicating roads and nodes connected by the links. The first map information 54 may also include 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 by, for example, the functions of a terminal device such as a smartphone or tablet device owned by the occupant. The navigation device 50 may transmit the current position and destination to a navigation server via the communication device 20 and obtain a route equivalent to the route on the map from the navigation server.

[0033] 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 meters in the vehicle's traveling direction), and determines a recommended lane for each block by referring to the second map information 62. The recommended lane determination unit 61 determines, for example, which lane from the left the vehicle should travel in. When there is a branch point on the route on the map, the recommended lane determination unit 61 determines a recommended lane so that the vehicle M can travel on a reasonable route to the branch point.

[0034] The second map information 62 is map information with higher accuracy than the first map information 54. The second map information 62 includes, for example, information on the centers of lanes or information on lane boundaries. The second map information 62 may also include information on the number of lanes and the road width (lane width). The second map information 62 may also include information indicating a merging section where a main lane and a merging lane merging into the main lane are connected, and information indicating a branching section where a main lane and a branching lane are connected. The information indicating a merging section includes, for example, position information on the start and end points of the merging section. The second map information 62 may also include, for example, information on the positions of the connecting ends (nose) of lanes in the branching section or merging section, the positions of zebra zones (guiding strips) and no-entry areas, information indicating whether or not there are road dividing lines (hereinafter referred to as dividing lines) separating the main lane from other lanes (merging lanes, branching lanes), and shape information on the merging section or branching section. The connection end may include, for example, the position of a hard nose (e.g., a position where merging is physically possible) or a soft nose (e.g., the end of a zebra zone), which are positions where merging is legally possible. The second map information 62 may also 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.

[0035] The driving operators 80 include, for example, an accelerator pedal, a brake pedal, a shift lever, a steering wheel, an irregular steering wheel, a joystick, 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 automatic driving control device 100 or some or all of the driving force output device 200, the brake device 210, and the steering device 220.

[0036] The autonomous driving control device 100 includes, for example, a first control unit 120, a second control unit 160, an HMI control unit 170, and a storage unit 180. The first control unit 120, the second control unit 160, and the HMI control unit 170 are each realized by a hardware processor, such as a central processing unit (CPU), executing a program (software). Some or all of these components may be realized by hardware (including circuitry), such as a large-scale integration (LSI), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a graphics processing unit (GPU), or a system-on-chip (SOC), 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 with a non-transitory storage medium) such as an HDD or flash memory of the automatic driving control device 100, or may be stored in a removable storage medium such as a DVD or CD-ROM, and installed in the HDD or flash memory of the automatic driving control device 100 by attaching the storage medium (non-transitory storage medium) to a drive device. The automatic driving control device 100 is an example of a "vehicle control device." The HMI control unit 170 is an example of a "notification control unit."

[0037] The storage unit 180 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), a random access memory (RAM), or the like. The storage unit 180 stores, for example, information, programs, and various other information required to execute the driving control in the first embodiment. The storage unit 180 may also store map information (first map information 54 and second map information 62).

[0038] FIG. 2 is a functional configuration diagram of the first control unit 120 and the second control unit 160. The first control unit 120, for example, implements functions based on AI (Artificial Intelligence) and functions based on a predefined model in parallel. For example, the "intersection recognition" function may be implemented by executing intersection recognition using deep learning or the like and recognition based on predefined conditions (such as traffic lights and road signs that can be pattern-matched) in parallel, and then scoring and comprehensively evaluating both. This ensures the reliability of autonomous driving. The first control unit 120 includes, for example, a recognition unit 130 and a behavior plan generation unit 140.

[0039] The recognition unit 130 recognizes the surrounding conditions of the vehicle M based on information obtained from at least one of the detection device DD and map information. For example, the recognition unit 130 recognizes the positions, speeds, accelerations, and other conditions of objects present around the vehicle M (e.g., within a predetermined distance from the vehicle M) based on information acquired from the detection device DD. Objects include other vehicles, traffic participants (pedestrians, bicycles, etc.) traveling on the road, road structures, and other surrounding objects. Road structures include, for example, road signs, traffic signals, railroad crossings, curbs, medians, guardrails, fences, and the like. Road structures may also include, for example, road markings drawn or affixed to the road surface that divide the road, pedestrian crossings, bicycle crossings, stop lines, zebra zones (guiding strips), no-entry areas, and other road markings, as well as information on the connecting ends of merging and branching sections (including soft noses and hard noses). The position of the 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 the object may be represented by a representative point such as the center of gravity or a corner of the object, or by a represented area. In the following description, the representative point of the host vehicle M is the center of gravity. When the object is another vehicle, the "state" of the object may include the acceleration or jerk of the object, or the "behavioral state" (e.g., whether or not the object is changing lanes or is about to change lanes). In addition, the recognition unit 130 may recognize the relative distance (remaining distance) to the object.

[0040] The recognition unit 130 may also recognize the shape, number of lanes, and driving lane (host vehicle lane) of the road on which the host vehicle M is traveling, based on information acquired from the detection device DD, for example. The recognition unit 130 may also recognize the shape, number of lanes, and driving lane of the road around the host vehicle M by referring to map information (first map information 54, second map information 62) based on position information of the host vehicle M acquired from the vehicle sensor 40 or the navigation device 50. In this case, the recognition unit 130 may recognize the shape of the surrounding road and lanes on the road by comparing the pattern of marking lines (e.g., the type and arrangement of solid and dashed lines) acquired from the map information with the pattern of marking lines around the host vehicle M recognized from the image captured by the camera 10. The recognition unit 130 may also recognize lanes by recognizing road boundaries (road boundaries) such as road structures, in addition to marking lines. The position of the host vehicle M acquired from the navigation device 50 and the processing results of the INS may also be taken into account in this recognition.

[0041] Furthermore, when recognizing the driving lane of the host vehicle M, the recognition unit 130 recognizes the position and attitude of the host vehicle M with respect to the driving lane. For example, the recognition unit 130 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 direction of travel 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 130 may recognize the position of the reference point of the host vehicle M with respect to one of the side edges of the driving lane (a dividing line or a road boundary) as the relative position of the host vehicle M with respect to the driving lane. Furthermore, the recognition unit 130 recognizes stop lines, obstacles, traffic lights, toll booths, and other road phenomena.

[0042] Furthermore, the recognition unit 130 recognizes various information for traveling through a merging section, such as a merging section present in the traveling direction of the vehicle M, lane connection information in the merging section, a connecting end of the merging section, line type, the number of lanes on the main lane, and road shape, based on information obtained from at least one of the detection device DD and map information. The connecting end of the merging section may include, for example, the start point, the end point, the position of a zebra zone, a soft nose, or a hard nose. Furthermore, the recognition unit 130 recognizes the position (relative position) and speed (relative speed) of other vehicles traveling on the main lane based on information obtained from the detection device DD.

[0043] Based on the recognition results of the recognition unit 130, the behavior plan generation unit 140 generates a target trajectory along which the host vehicle M will automatically (without driver operation) travel in the future so that the host vehicle M will travel, in principle, along the recommended lane determined by the recommended lane determination unit 61 and be able to respond to the surrounding conditions of the host vehicle M. The target trajectory includes, for example, a speed element. For example, the target trajectory is expressed as a sequential arrangement of points (trajectory points) to be reached by the host vehicle M. The trajectory points are points to be reached by the host vehicle M at predetermined travel distances (e.g., several meters) along a road. Separately, target speeds and target accelerations are generated as part of the target trajectory for each predetermined sampling time (e.g., several tenths of a second). Alternatively, the trajectory points may be positions to be reached by the host vehicle M at each sampling time for each predetermined sampling time. In this case, information on the target speed and target acceleration is expressed as the interval between trajectory points.

[0044] The behavior plan generation unit 140 may set an autonomous driving event when generating the target trajectory. The autonomous driving events include a constant speed driving event, a low-speed following driving event, a lane change event, a branching event, a merging event, a takeover event, an emergency stop event, etc. The behavior plan generation unit 140 generates a target trajectory according to the activated event. Furthermore, when generating the target trajectory, the behavior plan generation unit 140 adjusts the speed and the amount of lateral movement of the host vehicle M, etc.

[0045] The behavior plan generation unit 140 also includes, for example, a vehicle state acquisition unit 142, a position determination unit 144, and a merging control unit 146. The merging control unit 146 and the second control unit 160 are examples of a "driving control unit." The vehicle state acquisition unit 142, the position determination unit 144, and the merging control unit 146 are functions that are executed mainly when the host vehicle M merges (during a merging event). Details of these functions will be described later.

[0046] The second control unit 160 controls the driving force output device 200, the braking device 210, and the steering device 220 so that the vehicle M passes through the target trajectory generated by the action plan generation unit 140 at the scheduled time.

[0047] The second control unit 160 includes, for example, an acquisition unit 162, a speed control unit 164, and a steering control unit 166. The acquisition unit 162 acquires information on the target trajectory (trajectory points) generated by the action plan generation unit 140 and stores it in a memory (not shown). The speed control unit 164 controls the driving force output device 200 or the brake device 210 based on a speed element associated with the target trajectory stored in the memory. The steering control unit 166 controls the steering device 220 according to the curvature of the target trajectory stored in the memory. The processing of the speed control unit 164 and the steering control unit 166 is realized, for example, by a combination of feedforward control and feedback control. As an example, the steering control unit 166 executes a combination of feedforward control according to the curvature of the road ahead of the host vehicle M and feedback control based on the deviation from the target trajectory.

[0048] The HMI control unit 170 notifies the occupant of predetermined information via the HMI 30. The predetermined information includes, for example, information related to the driving 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, information related to the driving control status (e.g., the content of an event currently being executed), information for notifying the start or end of autonomous driving, and information related to the merging start position of the vehicle M when merging. The predetermined information may also include information unrelated to the driving control of the vehicle M, such as television programs, content (e.g., movies) stored on a storage medium such as a DVD, etc.

[0049] For example, the HMI control unit 170 may generate an image including the predetermined information and display the generated image on the display unit 32 of the HMI 30, or may generate a sound indicating the predetermined information and output the generated sound from the speaker 34 of the HMI 30. The HMI control unit 170 may also control the vibration unit 36 ​​to change the magnitude or period of vibration to notify the occupant of the merging start position or to call attention to the surrounding area. The HMI control unit 170 may also output the information received by the HMI 30 to the communication device 20, the navigation device 50, the first control unit 120, etc.

[0050] The driving force output device 200 outputs a driving force (torque) to the drive wheels to drive the vehicle. 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 second control unit 160 or information input from the driving operator 80.

[0051] Brake 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 a brake ECU. The brake ECU controls the electric motor according to information input from second control unit 160 or information input from driving operator 80, so that brake torque corresponding to the braking operation is output to each wheel. Brake 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 brake device 210 is not limited to the configuration described above, and may also be an electronically controlled hydraulic brake device that controls an actuator according to information input from second control unit 160 to transmit hydraulic pressure from a master cylinder to the cylinder.

[0052] The steering device 220 includes, for example, a steering ECU and an electric motor. The electric motor applies a force to, for example, 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 second control unit 160 or information input from the driving operator 80.

[0053] [Vehicle State Acquisition Unit, Position Determination Unit, and Merging Control Unit] Next, detailed descriptions will be given of the functions of the vehicle state acquisition unit, position determination unit 144, and merging control unit 146 of the behavior plan generation unit 140 in the first embodiment. FIG. 3 is a diagram for describing the processing when the host vehicle M merges from a merging lane onto a main lane. The example of FIG. 3 illustrates a road including a main lane consisting of two lanes L1 and L2 that can travel in the same direction (X-axis direction in the figure) and a merging lane L3 that merges into the main lane from the lane L1 side. In the example of FIG. 3, the host vehicle M is traveling toward the merging section MC at a speed VM before arriving at a section (merging section MC) where it is possible to merge (change lanes) from the merging lane L3 onto the main lane. Also, assume that another vehicle m1 is traveling at a speed Vm1 on the main lane L1, and another vehicle m2 is traveling behind the other vehicle m1 at a speed Vm2.

[0054] In the situation shown in Figure 3, the recognition unit 130 of the host vehicle M recognizes the surrounding conditions of the host vehicle M, and recognizes the road shape around the host vehicle M and other vehicles m1 and m2 that are present around the host vehicle M (within a predetermined distance). The recognized road shape includes, for example, the shapes of each of the lanes L1 to L3, the zebra zone ZZ, the positions of the hard nose HN and soft nose SN, the end point EP of the merging section, and the merging section MC. The recognition unit 130 also recognizes the positions and velocities Vm1 and Vm2 of the other vehicles m1 and m2. In the example of Figure 3, the soft nose SN is assumed to be the start point of the merging section MC.

[0055] For example, when the vehicle M is merging from a merging lane, such as a highway ramp, onto a main lane under automated driving, the merging start position affects the passenger comfort level. For example, if the merging start position is located far back (near the end of the merging section) in a situation where there are no other vehicles and it is clearly safe, the passengers may feel uneasy about when the merging will occur. Furthermore, if there are other vehicles near the merging section, a large speed difference before and after the merging may require sudden acceleration or deceleration, which may reduce the passenger comfort level. Therefore, in the first embodiment, a more appropriate merging start position is determined based on the positional relationship and speed of other vehicles at the time of merging, thereby suppressing speed fluctuations during merging and achieving more comfortable merging control.

[0056] The vehicle state acquisition unit 142 acquires the state of the host vehicle M based on the recognition result by the recognition unit 130. For example, in the situation shown in Fig. 3, the vehicle state acquisition unit 142 acquires that the host vehicle M will merge from the merging section onto the main lane in the near future. The vehicle state acquisition unit 142 may also acquire that the host vehicle M has reached the soft nose SN, which is the start point of the merging section MC.

[0057] The position determination unit 144 determines a merging start position where the host vehicle M starts merging from the merging lane L3 to the lane L1 based on the surrounding circumstances and the state of the host vehicle M. The merging start position is, for example, a position where at least steering of the host vehicle M is started due to autonomous driving. Note that the position determination unit 144 determines the merging start position in accordance with the determination rules shown below, for example, at the timing when the vehicle state acquisition unit 142 acquires that the host vehicle M has reached the soft nose SN.

[0058] First, when the host vehicle M reaches the soft nose SN, the position determination unit 144 sets a tentative merging start position P1 based on the shape of the merging section MC. The tentative merging start position P1 is a merging start position that has not yet been finally determined. For example, the position determination unit 144 sets the tentative merging start position P1 to a position on the merging section MC that is a predetermined distance D1 away (ahead) from the soft nose SN. The predetermined distance D1 is a fixed distance, but may also be, for example, a midpoint in the merging section MC, or may be variably set depending on the speed VM of the host vehicle M and the road shape.

[0059] Next, the position determination unit 144 derives a predicted time for the host vehicle M to reach the tentative merging start position P1 based on the speed VM at the time the host vehicle M reaches the soft-nose SN and the distance to the tentative merging start position P1. In the example of FIG. 3 , the predicted time is, for example, a value obtained by dividing the predetermined distance D1 by the speed VM. However, if the host vehicle M accelerates or decelerates before reaching the tentative merging start position P1, the speed VM may be a value that takes into account acceleration or deceleration (e.g., a predicted average speed). The position determination unit 144 then derives the relative positions (estimated positions) of the other vehicles m1 and m2 when the derived predicted time has elapsed and the tentative merging start position P1. The positions of the other vehicles m1 and m2 are, for example, the positions at the time the predicted time has elapsed, assuming that the other vehicles m1 and m2 move at a constant speed from the speeds Vm1 and Vm2 of the other vehicles m1 and m2 recognized when the host vehicle M reaches the soft-nose SN. The relative position is a relative position based on the direction in which the vehicle can travel on the main line (X axis in the drawing).

[0060] Here, the relative position includes, for example, a case where the tentative merging start position P1 is in front of the other vehicles m1 and m2 traveling on the main lane ((A) in the figure) (first relative position pattern), a case where the tentative merging start position P1 is between the other vehicles m1 and m2 ((B) in the figure) (second relative position pattern), and a case where the tentative merging start position P1 is behind the other vehicle m2 ((C) in the figure) (third relative position pattern). In the first relative position pattern, it is predicted that no other vehicles will be present in front of the host vehicle M when the host vehicle M reaches the tentative merging start position P1. In the second relative position pattern, it is predicted that the other vehicle m1 will be present in front of the host vehicle M and the other vehicle m2 will be present behind the host vehicle M when the host vehicle M reaches the tentative merging start position P1. In the third relative position pattern, it is predicted that the other vehicles m1 and m2 will be present in front of the host vehicle M when the host vehicle M reaches the tentative merging start position P1.

[0061] The position determination unit 144 then determines the final merging start position by applying a predetermined determination rule according to the above-described relative position. Specifically, the position determination unit 144 determines the merging start position according to a rule base (determination rule) for determining the merging start position according to the above-described first to third relative position patterns. The determination of the merging start position for each of the first to third relative position patterns will be described below.

[0062] <First Relative Position Pattern> In the case of the first relative position pattern, if the distance between the host vehicle M and the other vehicle (the other vehicle behind) is already equal to or greater than a predetermined distance when the host vehicle M reaches the start point of the merging section MC, the position determination unit 144 determines the merging start position P2 to be a position before the tentative merging start position P1 as seen from the host vehicle M. For example, if a sufficiently safe distance has already been secured behind the host vehicle M in the merging destination lane L1 when the host vehicle M reaches the soft nose, the position determination unit 144 determines the merging start position P2 to be a position near the soft nose SN (a position forward (farther) than the soft nose SN as seen from the host vehicle M by the predetermined distance α and before the tentative merging start position P1). A sufficiently safe distance is, for example, a distance at which the TTC between the host vehicle M and another vehicle is equal to or greater than the first threshold value even if the host vehicle M merges (changes lanes) from the merging lane L3 to the lane L1 with a speed change of less than a predetermined amount. The TTC may be, for example, a value derived by dividing the relative distance between the host vehicle M and another vehicle (e.g., the closest vehicle m1) by the relative speed, or may be a value corresponding to the relative distance. The predetermined distance α may be a fixed distance shorter than the predetermined distance D1, or may be a distance traveled for a predetermined time (e.g., approximately 1 to 2 seconds) after the host vehicle M passes the soft nose SN (enters the merging section MC) based on the speed VM of the host vehicle M. This allows the host vehicle M to move quickly after entering the merging section MC when the other vehicle is far away.

[0063] Furthermore, in the first relative position pattern, if the distance between the host vehicle M and the other vehicle is less than a predetermined distance when the host vehicle M reaches the start point of the merging section, the position determination unit 144 determines the tentative merging start position P1 as the merging start position P2. For example, even if a sufficiently safe distance is not secured when the host vehicle M reaches the soft nose SN, the position determination unit 144 determines the tentative merging start position P1 as the merging start position P2 if there is a certain degree of safe distance. In other words, even if the contact tolerance TTC is less than the first threshold, if it is equal to or greater than a second threshold that is smaller than the first threshold, the position determination unit 144 determines the tentative merging start position P1 as the merging start position P2.

[0064] <Second Relative Position Pattern> In the case of the second relative position pattern, the position determination unit 144 performs the following optimized position determination process to determine the merging start position. FIG. 4 is a diagram illustrating an example of the optimized position determination process. The horizontal axis of FIG. 4 represents time, and the vertical axis represents distance from the soft-nose SN. The example of FIG. 4 illustrates the future position transition over time, assuming that the speeds Vm1 and Vm2 of the other vehicles m1 and m2 recognized when the host vehicle M reaches the soft-nose SN remain unchanged (constant speed). The position of the host vehicle M in the example of FIG. 4 also illustrates the future position of the host vehicle M, taking into account the acceleration (speed change amount) required to merge from the merging lane L3 into the lane L1. This speed change amount may be a preset fixed speed change amount at the time of merging, or may be set based on the difference between the speed VM of the host vehicle M at the time the host vehicle M reaches the soft-nose SN and the legal speed limit of the main lane.

[0065] In the second relative position pattern, the position determination unit 144 determines the merging start position P2 based on the difference between the relative distance Fd from the other vehicle m1 to the vehicle M, which is based on the speed VM of the vehicle M and the speed Vm1 of the other vehicle m1 ahead of the hypothetical merging start position P1, and the relative distance Rd from the other vehicle m2 to the vehicle M, which is based on the speed VM of the vehicle M and the speed Vm2 of the other vehicle m2 behind the hypothetical merging start position P1.

[0066] More specifically, the position determination unit 144 determines the merging start position P2 as a position where the difference between the relative distance Fd between the vehicle m1 and the vehicle M and the relative distance Rd between the vehicle m2 and the vehicle M is small and where the relative distances Fd and Rd are maximum within the range from the soft nose SN (the start point of the merging section MC) to the end point EP of the merging section MC based on the future positional relationship between the vehicle M and the other vehicles m1 and m2 over time as shown in FIG. 4 . For example, the position determination unit 144 derives a position where the square of the difference between the relative distances Fd and Rd (Fd - Rd) is equal to or less than a threshold, and determines the derived position where the relative distances Fd and Rd are maximum as the merging start position. Note that if there are multiple positions where the relative distances Fd and Rd are maximum, the position determination unit 144 determines the position closest to the soft nose SN as the merging start position. This allows merging control to be executed early when the conditions are first satisfied. Furthermore, if the maximum value of the relative distances Fd and Rd is less than the threshold value, the position determining unit 144 does not need to determine the position as the merging start position P2.

[0067] If the merging start position that satisfies the above-described condition is a position closer than the position (soft nose SN+α) that is a predetermined distance α forward (farther) from the soft nose SN as viewed from the host vehicle M, the position determination unit 144 may determine the merging start position to be the position of the soft nose SN+α. This makes it easier for other vehicles in the vicinity (especially the following other vehicle m2) to recognize that the host vehicle M will be merging, and allows them to prepare for the host vehicle M's arrival. This allows for a smoother merging.

[0068] In addition, when the maximum value of the relative distances Fd and Rd between the soft nose SN and the end point EP is less than the threshold value and the merging start position cannot be determined, the position determination unit 144 determines the merging start position P2 to be a position that is forward (ahead) of the tentative merging start position P1 as viewed from the vehicle M and a predetermined distance before the end point EP.

[0069] FIG. 5 illustrates a situation in which the merging start position is changed to a position forward of the tentative merging start position P1. The example in FIG. 5 illustrates a situation in which, although the second relative position pattern applies, the inter-vehicle distance between the other vehicles m1 and m2 is small (the maximum value of the relative distances Fd and Rd is less than the threshold), and therefore it is predicted that merging between the other vehicles m1 and m2 is not possible. In this case, the position determination unit 144 determines the merging start position to be a predetermined distance β before the end point EP. The predetermined distance β is, for example, a distance calculated by adding a predetermined safety margin to the distance at which the host vehicle M is predicted to be able to change lanes from the merging lane L3 to the lane L1. For example, shifting the merging start position P2 forward (farther away) from the host vehicle M's perspective can suppress abrupt speed control. Furthermore, the host vehicle M can decelerate, for example, to allow the other vehicles m1 and m2 to overtake the host vehicle M, and then merge behind the other vehicle m2 with ample space to maneuver.

[0070] <Third Relative Position Pattern> In the third relative position pattern, when the distance between the host vehicle M and the other vehicle (the other vehicle ahead) is already equal to or greater than a predetermined distance when the host vehicle M reaches the start point of the merging section MC, the position determination unit 144 determines the merging start position P2 to be a position before the tentative merging start position P1 as seen from the host vehicle M. For example, when the host vehicle M reaches the soft nose, if a sufficiently safe distance is already secured ahead of the host vehicle M in the merging destination lane L1, the position determination unit 144 determines the merging start position P2 to be a position near the soft nose SN (a position forward (ahead) by a predetermined distance α from the soft nose SN and before the tentative merging start position P1), as shown in FIG. 3 . This allows the host vehicle M to move at an early timing after entering the merging section MC when the other vehicle is far away.

[0071] Furthermore, in the third relative position pattern, if the distance between the host vehicle M and the other vehicle is less than a predetermined distance when the host vehicle M reaches the start point of the merging section, the position determination unit 144 determines the tentative merging start position P1 as the merging start position P2. For example, even if a sufficiently safe distance is not secured when the host vehicle M reaches the soft nose SN, the position determination unit 144 determines the tentative merging start position P1 as the merging start position P2 if there is a certain degree of safe distance. In other words, even if the contact tolerance TTC is less than the first threshold, if it is equal to or greater than a second threshold that is smaller than the first threshold, the position determination unit 144 determines the tentative merging start position P1 as the merging start position P2.

[0072] In addition, when the other vehicle m2 behind is accelerating and approaching the other vehicle m1 in front or the vehicle M, the position determination unit 144 may determine the merging start position P2 by shifting the relative position to a third relative position pattern, since it is highly likely that a safe distance will not be able to be secured even if the derived relative position is the first relative position pattern or the second relative position pattern.

[0073] In this way, the position determination unit 144 sets a tentative merging start position P1 when the host vehicle M reaches the start point of the merging section (soft nose SN), and determines a final merging start position based on the relative positions of the other vehicles m1 and m2 (other vehicles traveling on the main lane) with respect to the tentative merging start position P1. This makes it possible to determine a more appropriate merging start position depending on the surrounding conditions of the other vehicles, etc., thereby achieving more comfortable merging control. Note that if there are no other vehicles around the host vehicle M when the host vehicle M reaches the soft nose SN, the tentative merging start position P1 may not be set, and a position near the soft nose SN (soft nose SN + predetermined distance α) may be determined as the merging start position P2.

[0074] The merging control unit 146 generates an action plan (speed plan and steering plan) including steering control for changing lanes onto the main lane when the host vehicle M reaches the merging start position P2 determined by the position determination unit 144, and generates a target trajectory corresponding to the generated action plan. By having the second control unit 160 execute driving control based on this target trajectory, the host vehicle M is allowed to merge smoothly with less speed difference. Note that the speed plan (speed control) may be executed before the host vehicle M reaches the merging start position P2.

[0075] Note that, for speed planning, known techniques such as those described in Japanese Patent Application Laid-Open No. 2022-107296 filed by the present applicant may be applied. For example, the merging control unit 146 calculates a state value for each of multiple state paths between a start time and a target time, which are defined by selecting from multiple candidates an action amount (e.g., an action amount) occurring between multiple time points between a start time and a target time point in a state space having axes including time and multiple elements related to the movement of the host vehicle M (time, some or all of the position, speed, and acceleration in the vehicle's traveling direction), and determines the future speed transition of the host vehicle M according to the state path with the highest calculated state value. Furthermore, the merging control unit 146 calculates a reward function value based on one or more evaluation target quantities for each time point between the start time and the target time point, and calculates the state value by summing the reward function values ​​in a time series. The state value is calculated according to a first region that reduces the state value and a second region that reduces the reward function value, which are set in some or all of multiple subspaces having axes based on two or more of the multiple elements. This makes it possible to obtain a suitable solution by setting appropriate constraints when performing speed control that takes future conditions into consideration.

[0076] Furthermore, if a safe distance for merging cannot be ensured due to, for example, a change in the speeds Vm1 and Vm2 of the other vehicles m1 and m2 while the vehicle M is traveling toward the determined merging start position P2, the position determination unit 144 changes the merging start position to a position further forward (farther away) than the current position as viewed from the vehicle M, in order to re-execute a plan that deviates from the initial speed plan. In this case, the position determination unit 144 sets the merging start position P2 to a position a predetermined distance β before the end point EP, as described above. This allows, for example, deceleration control with a small amount of speed change to be performed, allowing the other vehicles m1 and m2 to go ahead, and then allowing the vehicle M to safely merge behind the other vehicle m2.

[0077] Furthermore, the position determination unit 144 may change the merging start position depending on the relative speed between the host vehicle M and the other vehicles m1 and m2. For example, if the speed of the other vehicle behind the host vehicle M is faster than the speed VM of the host vehicle M and the relative speed is equal to or greater than a predetermined speed, the predicted relative position is likely to change, so the merging start position is changed to a position further forward (farther away) from the host vehicle M than the current position. Furthermore, if the speed of the other vehicle behind the host vehicle M is slower than the speed of the host vehicle M and the relative speed is high, the position determination unit 144 changes the merging start position to a position closer to the host vehicle M than the current position. This makes it possible to set a more appropriate merging start position depending on the relative speed between the host vehicle M and the other vehicle.

[0078] In the first embodiment, the HMI control unit 170 generates information (images and sounds) related to the automatic driving control (event) executed by the driving control unit or the automatic driving control scheduled to be executed in the near future, and displays the information on the display unit 32 of the HMI 30 or outputs the information as sound from the speaker 34. Furthermore, when switching from automatic driving to manual driving in accordance with surrounding conditions, road shape, etc., the HMI control unit 170 may output images and sounds to prompt the occupant to perform manual driving, and may also vibrate the driver's seat or steering wheel using the vibration unit 36 ​​to notify the occupant of the host vehicle M of information related to the merging start position determined by the above-described method in a merging event.

[0079] [Processing Flow of First Embodiment] Next, a process executed by the vehicle control device (automatic driving control device 100) of the first embodiment will be described using a flowchart. FIG. 6 is a flowchart illustrating an example of a process executed by the automatic driving control device 100. Note that the process in FIG. 6 will be described mainly focusing on the control process at the time of merging, among the processes executed by the automatic driving control device 100. In the example of FIG. 6, the recognition unit 130 recognizes the surrounding conditions of the host vehicle M (step S100). Next, the recognition unit 130 determines whether a merging section exists in the traveling direction of the host vehicle M, allowing the host vehicle M to merge from the merging lane onto the main lane (step S200). If it is determined that a merging section exists, the action plan generation unit 140 determines a merging start position (step S300) and causes the second control unit 160 to execute merging control (merging event) to merge onto the main lane based on the determined merging start position (step S400). This ends the process of this flowchart.

[0080] Furthermore, if it is determined in the processing of step S200 that there is no merging section in the traveling direction, this flowchart ends. Note that, if the automatic driving control device 100 is executing automatic driving control such as ACC, that control continues. Furthermore, if the merging control has ended normally, the automatic driving control device 100 may end the merging control and return to the previous automatic driving control (for example, ACC control).

[0081] FIG. 7 is a flowchart illustrating an example of the position determination process. The process in FIG. 7 illustrates the details of step S300. In the example in FIG. 7 , the position determination unit 144 determines whether another vehicle is present on the main lane (the lane to which the vehicle is to merge) based on the recognition result by the recognition unit 130 (step S302). If it is determined that another vehicle is present, the position determination unit 144 determines whether the host vehicle M has reached the soft nose SN (an example of the start point of the merging section MC) (step S304). If it is determined that the host vehicle M has not reached the soft nose SN, the position determination unit 144 waits until the host vehicle M reaches the soft nose SN. If it is determined that the host vehicle M has reached the soft nose SN, the position determination unit 144 sets a tentative merging start position P1 (step S306) and further derives a predicted time until the host vehicle M reaches the merging start position P1 (step S308). Next, the position determination unit 144 derives the relative position between the position of the other vehicle after the predicted time has elapsed and the tentative merging start position P1 (step S310). Next, the position determination unit 144 determines the merging start position P2 based on the derived relative position (step S312). Details of the process of step S312 will be described later.

[0082] Next, the position determination unit 144 determines whether the host vehicle M is a safe distance away from the merging start position P2 while moving to the merging start position P2 (step S314). If it is determined that the host vehicle M is a safe distance away from the merging start position P2, the position determination unit 144 determines whether the host vehicle M has reached the merging start position P2 (step S316). If it is determined that the host vehicle M has not reached the merging start position, the process returns to step S314. If it is determined that the host vehicle M has reached the merging start position, the process of this flowchart ends, and the merging control of step S400 is executed.

[0083] If it is determined in step S314 that the distance is not safe, the position determination unit 144 changes the merging start position to a position further forward (farther away) than the current position as viewed from the vehicle M (step S318). Then, the processing of this flowchart ends, and the merging control of step S400 is executed. If it is determined in step S302 that no other vehicle is present on the main lane, the position determination unit 144 determines the merging start position P2 to be the position of soft nose SN+α (step S320), then the processing of this flowchart ends, and the merging control of step S400 is executed.

[0084] FIG. 8 is a flowchart illustrating an example of a process for determining a merging start position based on a relative position. The process in FIG. 8 illustrates details of the process in step S312 described above. In the example in FIG. 8, the position determination unit 144 determines whether the relative position corresponds to the first relative position pattern (step S312A). If the relative position corresponds to the first relative position pattern, the position determination unit 144 determines whether there is a sufficiently safe distance between the vehicle M and the other vehicle (the vehicle behind) for merging (changing lanes) when the vehicle M reaches the soft nose SN (step S312B). If it determines that there is a sufficiently safe distance, the position determination unit 144 determines the merging start position to be near the soft nose SN (soft nose + α) (step S312C). This position is located before the tentative merging start position as viewed from the vehicle M. This completes the process in this flowchart.

[0085] Furthermore, if the process of step S312B determines that there is already not a sufficiently safe distance for the soft nose SN, the position determination unit 144 sets the tentative merging start position P1 as the merging start position P2 (step S312D). Next, the position determination unit 144 determines whether there is a sufficiently safe distance for merging at the determined merging start position (step S312E). If it is determined that there is a sufficiently safe distance, the process ends. If the process of step S312E determines that there is not a sufficiently safe distance, the position determination unit 144 sets the merging start position P2 to a position a predetermined distance β before the end point EP of the merging section MC (step S312F), and then ends the process of the process. This position is, for example, a position that is further forward (farther away) from the host vehicle M than the set tentative merging start position.

[0086] Furthermore, if it is determined in the processing of step S312A that the relative position does not conform to the first relative position pattern, the position determination unit 144 determines whether the relative position conforms to the second relative position pattern (step S312G). If it is determined that the relative position conforms to the second relative position pattern, the position determination unit 144 determines whether there is a sufficient distance (a predetermined distance or more) between the vehicle and another vehicle ahead or behind the merging position (step S312H). If it is determined that there is not a sufficient distance, the position determination unit 144 determines the merging start position to be a position a predetermined distance before the end point EP (step S312F) and ends the processing of this flowchart. If it is determined that there is a sufficient distance, the position determination unit 144 executes the above-described optimized position determination processing to determine the merging start position (step S312I) and ends the processing of this flowchart.

[0087] Furthermore, if the processing of step S312G determines that the second relative position pattern is not the case, the position determination unit 144 determines whether there is already a sufficiently safe distance between the host vehicle M and the other vehicle (the other vehicle ahead) for merging (changing lanes) when the host vehicle M reaches the soft nose SN (step S312J), as a third relative position pattern. If it is determined that there is a sufficiently safe distance, the position determination unit 144 determines the merging start position to be near the soft nose SN (soft nose + α) (step S312K). This position is a position before the tentative merging start position as seen from the host vehicle M. This ends the processing of this flowchart.

[0088] Furthermore, if the process of step S312J determines that there is already not a sufficiently safe distance for the soft nose SN, the position determination unit 144 sets the tentative merging start position P1 as the merging start position P2 (step S312L). Next, the position determination unit 144 determines whether there is a sufficiently safe distance for merging at the determined merging start position (step S312M). If it is determined that there is a sufficiently safe distance, the process of this flowchart ends. If the process of step S312M determines that there is not a sufficiently safe distance, the position determination unit 144 sets the merging start position P2 to a position a predetermined distance β before the end point EP of the merging section MC (step S312F), and then the process of this flowchart ends.

[0089] According to the first embodiment described above, the vehicle control device includes a recognition unit 130, 320 that recognizes the surrounding conditions of the host vehicle M, a vehicle state acquisition unit 142, 342 that acquires the state of the host vehicle M, and a position determination unit 144, 344 that determines a merging start position at which the host vehicle M starts merging from the merging lane onto the main lane based on the surrounding conditions and the state of the host vehicle M. The position determination unit 144, 344 sets a tentative merging start position based on the shape of the merging section, derives a relative position between the positions of other vehicles present around the host vehicle and the tentative merging start position when a predicted time until the host vehicle reaches the set tentative merging start position has elapsed, and determines the merging start position by applying a predetermined determination rule based on the derived relative position. This allows for a more appropriate merging start position to be determined when merging onto the main lane. Therefore, the host vehicle can be more appropriately merged. For example, according to the first embodiment, the merging start position of the host vehicle can be determined based on the positional relationship and speed of other vehicles in the vicinity, thereby achieving a more comfortable automatic merging experience for the occupants.

[0090] More specifically, according to the first embodiment, for example, if a tentative merging start position is initially set and it is determined that merging is difficult (unsafe) before reaching the merging start position, the merging start position is postponed further forward, thereby reducing the amount of speed change in the longitudinal direction (travel direction) and achieving a smooth merging with little speed difference. Furthermore, according to the first embodiment, the merging start position is determined at a predetermined timing rather than being changed as needed, thereby reducing the processing load caused by changes to action plans such as speed plans. Furthermore, according to the first embodiment, merging at an appropriate timing depending on the surrounding traffic conditions can improve passenger comfort. Furthermore, merging at an appropriate timing when there is another vehicle on the main lane can improve passenger comfort when merging.

[0091] [Second embodiment] The vehicle control device may be applied not only to autonomous vehicles but also to driving assistance devices such as ADAS. Fig. 9 is a diagram showing an example of the configuration of a vehicle system 2 equipped with a vehicle control device according to the second embodiment. Note that in the following configuration, components having at least the same functions as those in the vehicle system 1 of the first embodiment are given the same reference numerals and names, and specific descriptions thereof will be omitted.

[0092] The vehicle system 2 includes, for example, a camera 10, a radar device 12, a LIDAR 14, an object recognition device 16, a communication device 20, an HMI 30, vehicle sensors 40, a navigation device 50, an MPU 60, a driving operator 80, a driving assistance device 300, a driving force output device 200, a brake device 210, and a steering device 220. These devices and equipment are connected to each other via multiplexed communication lines such as a CAN communication line, serial communication lines, a wireless communication network, or the like. Note that the configuration shown in FIG. 9 is merely an example, and some of the configuration may be omitted, or other configurations may be added. In the second embodiment, the driving assistance device 300 is an example of a "vehicle control device." Compared to the vehicle system 1 of the first embodiment, the vehicle system 2 differs in that the vehicle system 2 includes the driving assistance device 300 instead of the automatic driving control device 100. Therefore, the following description will mainly focus on the functions of the driving assistance device 300.

[0093] The driving assistance device 300 includes, for example, a recognition unit 320, a driving assistance control unit 340, an HMI control unit 360, and a storage unit 380. The recognition unit 320, the driving assistance control unit 340, and the HMI control unit 360 are each realized by, for example, a hardware processor such as a CPU executing a program (software). Furthermore, some or all of these components may be realized by hardware (including circuitry) such as an LSI, ASIC, FPGA, GPU, or SOC, or may be realized by a combination of software and hardware. The program may be stored in advance in a storage device (storage device with a non-transitory storage medium) such as an HDD or flash memory of the driving assistance device 300, 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 300 by inserting the storage medium (non-transitory storage medium) into a drive device. The HMI control unit 360 is an example of a "notification control unit."

[0094] The storage unit 380 may be realized by the various storage devices described above, or an SSD, an EEPROM, a ROM, a RAM, or the like. The storage unit 380 stores, for example, information, programs, and various other information required to execute the driving control in the second embodiment. The storage unit 380 may also store map information (first map information 54 and second map information 62).

[0095] The recognition unit 320 performs the same processing as the recognition unit 130 described above, and recognizes the surrounding conditions of the vehicle M based on information obtained from at least one of the detection device DD and map information.

[0096] The driving assistance control unit 340 executes driving assistance control (hereinafter referred to as ADAS (Advanced Driver Assistance System)) for the driver based on the results of recognition by the recognition unit 320. Examples of ADAS include, but are not limited to, Road Departure Mitigation (RDM), Forward Collision Warning (FCW), Collision Mitigation Braking System (CMBS), Adaptive Cruise Control (ACC), and Auto Lane Change Assist (ALCA). The ADAS may also include driving assistance control when merging.

[0097] For example, the driving assistance control unit 340 has a function of notifying the occupant of the merging start position in a predetermined notification manner when merging. The driving assistance control unit 340 includes, for example, a vehicle state acquisition unit 342, a position determination unit 344, and a merging assistance unit 346. Similar to the vehicle state acquisition unit 142 of the first embodiment, the vehicle state acquisition unit 342 acquires information that the host vehicle M will be merging from the merging section onto the main lane in the near future.

[0098] The position determination unit 344 determines the merging start position where the host vehicle M starts merging from the merging lane onto the main lane based on the surrounding circumstances and the state of the host vehicle M, by the processing of the position determination unit 144 in the first embodiment. When performing the optimized position determination process in the second relative position pattern described above, the position determination unit 344 may set a line indicating the position of the host vehicle M over time based on merging speed information included in the driver's past driving history (profile). The past driving history is stored in the storage unit 380. This makes it possible to compare the relative position with other vehicles in accordance with the driver's characteristics (habits), etc., and to set a more appropriate merging start position.

[0099] The merging support unit 346 provides support for merging the host vehicle M into a main lane through manual driving by the driver of the host vehicle M. The function of the merging support unit 346 will be described in detail later.

[0100] The HMI control unit 360 performs control to notify occupants such as the driver of information related to the driving assistance performed by the driving assistance control unit 340. For example, under the control of the merging assistance unit 346, the HMI control unit 360 performs control to display an image indicating the merging start position on the display unit 32 of the HMI 30, output a sound indicating the merging start position from the speaker 34, and activate vibrations according to the merging start position using the vibration unit 36.

[0101] Next, a detailed description will be given of the function of the merging support unit 346. For example, when the position determination unit 344 determines a merging start position P2 where the host vehicle M starts merging from the merging lane onto the main lane, the merging support unit 346 controls the HMI control unit 360 to notify the occupant of the merging start position in a notification manner according to the distance between the merging start position P2 and the host vehicle M.

[0102] The HMI control unit 360 controls the merging assistance unit 346 to change the manner of notification indicating the merging start position, for example, by changing the loudness (volume) and pitch of the sound, the amount of vibration of the seat caused by the vibration unit 36, the display manner of the image, etc. For example, the closer the host vehicle M is to the merging start position P2, the more the HMI control unit 360 emphasizes the merging start position P2 by using sound, images, and haptic (tactile) notification using vibration, etc.

[0103] 10 is a diagram for explaining a mode of notification of a merging start position in the second embodiment. The horizontal axis of Fig. 10 indicates the position of the vehicle M, and the vertical axis indicates the volume or vibration amount.

[0104] For example, the HMI control unit 360 adjusts the volume of the predetermined sound indicating the merging start position so that it increases toward a preset maximum value as the host vehicle M approaches the merging start position P2 (as the distance from the host vehicle M to the merging start position P2 decreases), and outputs the sound from the speaker 34. In this case, the HMI control unit 360 may increase the volume in a curved manner, or in a stepwise manner, as shown in Fig. 10 . Alternatively, the HMI control unit 360 may increase the volume linearly (in a straight line) as the host vehicle M approaches the merging start position P2.

[0105] Furthermore, the closer the host vehicle M gets to the merging start position P2, the greater the vibration of the seat or the like in the vibration unit 36, instead of (or in addition to) the sound. Furthermore, the closer the host vehicle M gets to the merging start position P2, the faster the period (pitch) of the sound or the period (pitch) of the vibration.

[0106] Furthermore, instead of (or in addition to) sound or vibration, the HMI control unit 360 may notify the driver by displaying the merging start position on a HUD or the like. In this case, the HMI control unit 360 displays an image indicating the merging start position so that it is more emphasized as the host vehicle M approaches the merging start position. Emphasis includes using a color or size that is easy for the occupant to see, flashing, or changing the shape or type of the image (shape or line) indicating the merging start position.

[0107] Furthermore, the HMI control unit 360 may change the type and number of notifications depending on the distance between the host vehicle M and the merging start position P2. For example, the HMI control unit 360 may notify the occupant only by displaying an image when the distance between the host vehicle M and the merging start position P2 is equal to or greater than a first predetermined distance, notify the occupant by image and sound when the distance between the host vehicle M and the merging start position P2 is within a second predetermined distance that is shorter than the first predetermined distance, and notify the occupant by image, sound, and vibration when the distance between the host vehicle M and the merging start position P2 is within a third predetermined distance that is further shorter than the second predetermined distance. This allows the occupant to reliably grasp the merging start position and enable manual driving to merge at a more appropriate time.

[0108] Furthermore, the HMI control unit 360 may emphasize the merging start position P2 as it approaches the merging end (end point). By emphasizing the merging start position P2 as it approaches the merging section MC, the driver can be more reliably informed of the merging (steering) operation.

[0109] Furthermore, the HMI control unit 360 may issue a notification to accelerate the vehicle M in accordance with the distance from the vehicle M to the merging start position P2 so that the vehicle M reaches an appropriate speed by the time it reaches the merging start position P2. This allows the vehicle M to reach a more appropriate speed by the time it reaches the steering start position. Furthermore, the HMI control unit 360 terminates the above-described notification when it determines that the driver has performed a driving operation to cause the vehicle M to merge at the merging start position P2. In this case, the HMI control unit 360 determines that the driver has performed a driving operation to cause the vehicle M to merge, for example, when the steering amount of the steering wheel is equal to or greater than a predetermined amount or when the vehicle M has entered the main lane.

[0110] [Processing Flow of the Second Embodiment] FIG. 11 is a flowchart illustrating an example of processing executed by the vehicle control device of the second embodiment. In the example of FIG. 11, the recognition unit 320 recognizes the surrounding conditions of the host vehicle M (step S500). Next, the recognition unit 320 determines whether a merging section exists in the direction of travel of the host vehicle M (step S600). If it is determined that a merging section exists, the position determination unit 144 determines a merging start position (step S700). The processing of steps S500 to S700 is similar to, for example, steps S100 to S300 of the first embodiment. Next, the merging assistance unit 346 provides merging assistance by, for example, notifying the driver of the host vehicle M to begin manual driving (steering) at the determined merging start position to merge onto the main lane (step S800). This completes the processing of this flowchart.

[0111] If it is determined in step S600 that there is no merging lane in the traveling direction, the process of this flowchart ends.

[0112] According to the second embodiment described above, by notifying the driver of the host vehicle M of the merging start position, even a driver who is not good at merging or a novice driver can perform merging driving at a more appropriate timing depending on the surrounding conditions. Therefore, according to the second embodiment, by determining a more appropriate merging start position, the host vehicle can be more appropriately merged.

[0113] [Modifications] Each of the first and second embodiments described above may be combined with part or all of the other embodiments. For example, in the first embodiment, the merging start position may be notified by an image. This allows the host vehicle M to determine the merging start position and notify the occupant that merging will begin at that position, thereby ensuring that the occupant understands that merging will begin, and reassuring the occupant. Note that during autonomous driving, since occupant driving is not required, at least notification by vibration may not be provided. This can prevent excessive notifications.

[0114] The above-described embodiment can be expressed as follows: A vehicle control device comprising: a storage medium storing computer-readable instructions; and a processor connected to the storage medium, wherein the processor executes the computer-readable instructions to: recognize a surrounding situation of a host vehicle, acquire a state of the host vehicle, determine a merging start position in a merging section where the host vehicle will start merging from a merging lane onto a main lane based on the surrounding situation and the state of the host vehicle, set a tentative merging start position based on a shape of the merging section, derive a relative position between the tentative merging start position and positions of other vehicles present in the vicinity of the host vehicle when a predicted time until the host vehicle reaches the set tentative merging start position has elapsed, and determine the merging start position by applying a predetermined decision rule in accordance with the derived relative position.

[0115] 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.

[0116] 1, 2...vehicle system, 10...camera, 12...radar device, 14...LIDAR, 16...object recognition device, 20...communication device, 30...HMI, 40...vehicle sensor, 50...navigation device, 80...driving operator, 100...automatic driving control device, 120...first control unit, 130, 320...recognition unit, 140...action plan generation unit, 142, 342...vehicle state acquisition unit, 144, 344...position determination unit, 146...merging control unit, 160...second control unit, 162...acquisition unit, 164...speed control unit, 166...steering control unit, 170, 360...HMI control unit, 180, 380...memory unit, 200...traveling drive force output device, 210...brake device, 220...steering device, 300...driving assistance device, 340...driving assistance control unit, 346...merging assistance unit

Claims

1. A vehicle control device comprising: a recognition unit that recognizes the surrounding conditions of a host vehicle; a vehicle state acquisition unit that acquires the state of the host vehicle; and a position determination unit that determines a merging start position at which the host vehicle will start merging from a merging lane to a main lane in a merging section based on the surrounding conditions and the state of the host vehicle, wherein the position determination unit sets a tentative merging start position based on a shape of the merging section, derives a relative position between the positions of other vehicles present in the vicinity of the host vehicle and the tentative merging start position when a predicted time has elapsed until the host vehicle reaches the set tentative merging start position, and determines the merging start position by applying a predetermined decision rule in accordance with the derived relative position.

2. The vehicle control device according to claim 1, further comprising a driving control unit that controls at least the steering of the vehicle, or the speed, when the vehicle reaches the merging start position determined by the position determination unit, to cause the vehicle to merge from the merging lane onto the main lane.

3. The vehicle control device of claim 1, wherein the position determination unit determines the merging start position to be a position shorter than the tentative merging start position as seen from the vehicle when the position of the other vehicle relative to the tentative merging start position is in front of or behind the tentative merging start position and the distance between the vehicle and the other vehicle is already greater than a predetermined distance when the vehicle reaches the start point of the merging section.

4. The vehicle control device according to claim 1, wherein the position determination unit determines the tentative merging start position to be the merging start position when the position of the other vehicle relative to the tentative merging start position is in front of or behind the tentative merging start position and when the distance between the host vehicle and the other vehicle is less than a predetermined distance when the host vehicle reaches the start point of the merging section.

5. The vehicle control device of claim 1, wherein, when the tentative merging start position is between a plurality of other vehicles, the position determination unit determines the merging start position based on the difference between the relative distance from the other vehicle in front to the host vehicle, which is based on the speed of the host vehicle and the speed of the other vehicle ahead of the tentative merging start position, and the relative distance from the other vehicle behind the host vehicle, which is based on the speed of the host vehicle and the speed of the other vehicle behind the tentative merging start position.

6. The vehicle control device according to claim 1, wherein, after determining the merging start position, if it is determined that it is unsafe to start merging at the merging start position before the vehicle reaches the merging start position, the position determination unit changes the merging start position to a position farther away than a current position as seen from the vehicle.

7. The vehicle control device according to claim 1, further comprising a notification control unit that notifies an occupant of the host vehicle of the determined merging start position in a notification manner according to a distance between the determined merging start position and the host vehicle.

8. The vehicle control device according to claim 7, wherein the notification control unit notifies the merging start position in a more emphasized manner as the host vehicle approaches the merging start position.

9. A vehicle control method in which a computer recognizes a surrounding condition of a host vehicle, acquires a state of the host vehicle, determines a merging start position at which the host vehicle will start merging from a merging lane to a main lane in a merging section based on the surrounding condition and the state of the host vehicle, sets a tentative merging start position based on a shape of the merging section, derives a relative position between the positions of other vehicles present in the vicinity of the host vehicle and the tentative merging start position when a predicted time has elapsed until the host vehicle reaches the set tentative merging start position, and determines the merging start position by applying a predetermined decision rule in accordance with the derived relative position.

10. A program which causes a computer to recognize the surrounding conditions of a host vehicle, acquire the status of the host vehicle, determine a merging start position at which the host vehicle will begin merging from a merging lane to a main lane in a merging section based on the surrounding conditions and the status of the host vehicle, set a tentative merging start position based on the shape of the merging section, derive a relative position between the positions of other vehicles present in the vicinity of the host vehicle and the tentative merging start position when a predicted time has elapsed until the host vehicle reaches the set tentative merging start position, and determine the merging start position by applying a predetermined decision rule in accordance with the derived relative position.

Images