Vehicle control device, vehicle control computer program, and vehicle control method

Abstract

To provide a vehicle control device which, on the basis of an average vehicle speed in each of multiple lanes of a road on which a vehicle travels, estimates a state of the whole road and can appropriately reflect the state of the whole road to the control of the vehicle.SOLUTION: A vehicle control device comprises: a speed calculation unit for calculating, for each of multiple lanes of a travel road on which a vehicle travels, an average speed of the vehicle traveling in the lane or another vehicle within a predetermined range from the vehicle, as an average vehicle speed in the lane; a state estimation unit for determining, for each of the multiple lanes of the travel road, whether the lane is congested on the basis of the average vehicle speed in the lane, and estimating whether the whole travel road is congested on the basis of a proportion of congested lanes in the travel road; and a determination unit for determining to drive the vehicle by automatic control when the whole travel road is congested.SELECTED DRAWING: Figure 2

Description

[Technical Field]

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

[0002] An automatic control system mounted on a vehicle acquires vehicle state information such as speed using sensors mounted on the vehicle, and controls the operation of the vehicle based on this vehicle state information. For example, the automatic control system detects the flow of vehicles in the lane in which the vehicle is traveling based on the vehicle speed, and starts automatic control of the vehicle when the vehicle speed falls below a predetermined reference speed. This allows the driver to be relieved from driving the vehicle when the road is congested.

[0003] Here, when the road on which the vehicle is traveling has multiple lanes, the state of vehicle flow may differ for each lane.

[0004] For example, Patent Document 1 proposes a congestion determination device that uses a millimeter wave sensor installed on a road to measure vehicle speed, calculates the average vehicle speed for the entire road from the sum of the number and speed of passing vehicles in each lane within the measurement range, and determines that the road is congested if the average vehicle speed for the entire road is lower than the congestion speed. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-288674 Summary of the Invention [Problem to be solved by the invention]

[0006] However, since vehicle speeds may differ between passing lanes and non-passing lanes, determining road congestion based on the average vehicle speed for the entire road with multiple lanes may result in an inaccurate assessment of road conditions.

[0007] Therefore, the present disclosure aims to provide a vehicle control device that can estimate the overall road condition based on the average vehicle speed of each of the multiple lanes on the road on which the vehicle is traveling, and appropriately reflect the overall road condition in the control of the vehicle. [Means for solving the problem]

[0008] (1) According to one embodiment, there is provided a vehicle control device comprising: a speed calculation unit that calculates, for each of a plurality of lanes of a road on which a vehicle is traveling, an average speed of vehicles traveling on that lane or other vehicles within a predetermined range from the vehicle as an average vehicle speed of that lane; a state estimation unit that determines, for each of a plurality of lanes of the road on which a vehicle is traveling, whether or not the lane is congested based on the average vehicle speed of that lane and estimates whether or not the entire road is congested based on the proportion of lanes that are congested within the road; and a determination unit that determines to drive the vehicle automatically when the entire road is congested.

[0009] (2) In the vehicle control device of (1), it is preferable that the state estimation unit determines that each of the multiple lanes of the road is congested if the average vehicle speed of that lane is equal to or less than a speed reference value set for that lane.

[0010] (3) In the vehicle control device of (2), it is preferable that the state estimation unit sets a speed reference value for each of multiple lanes of the road based on the average value of the average vehicle speed of that lane during a predetermined reference time.

[0011] (4) In the vehicle control device of (2) or (3), when the branch point where another road branches off from the traveling road is within a first range from the current position of the vehicle in the direction of travel, it is preferable that the state estimation unit increases the speed reference value for each of the multiple lanes of the traveling road.

[0012] (5) In any of the vehicle control devices (2) to (4), when the merging point where another road merges into the traveling road is within a second range from the current position of the vehicle in the traveling direction, it is preferable that the state estimation unit reduces the speed reference value for each of the multiple lanes of the traveling road.

[0013] (6) According to another embodiment, there is provided a computer program for controlling a vehicle, which causes a processor to perform the following operations: for each of a plurality of lanes of a road on which a vehicle is traveling, calculate an average speed of vehicles traveling in that lane or other vehicles within a predetermined range from the vehicle as an average vehicle speed of that lane; for each of a plurality of lanes of the road on which a vehicle is traveling, determine whether or not that lane is congested based on the average vehicle speed of that lane; estimate whether or not the entire road on which a vehicle is traveling is congested based on the proportion of lanes congested within the road; and, if the entire road on which a vehicle is traveling is congested, determine to drive the vehicle under automatic control.

[0014] (7) According to another embodiment, there is provided a vehicle control method, characterized in that a vehicle control device executes the following steps: for each of a plurality of lanes of a road on which a vehicle is traveling, calculates an average speed of vehicles traveling in that lane or other vehicles within a predetermined range from the vehicle as the average vehicle speed of that lane; for each of a plurality of lanes of the road on which a vehicle is traveling, determines whether or not that lane is congested based on the average vehicle speed of that lane; estimates whether or not the entire road is congested based on the proportion of lanes in the road that are congested; and, if the entire road is congested, determines to drive the vehicle under automatic control. [Effects of the Invention]

[0015] The vehicle control device according to the present disclosure estimates the overall road condition based on the average vehicle speed of each of the multiple lanes of the road on which the vehicle is traveling, and therefore the overall road condition can be appropriately reflected in the control of the vehicle. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a diagram illustrating an outline of the operation of a vehicle control system including a traffic congestion determination device according to an embodiment of the present invention. [Figure 2] 1 is a schematic configuration diagram of a vehicle in which a congestion determination device according to an embodiment of the present invention is implemented; [Figure 3] 4 is an example of an operational flowchart relating to an average vehicle speed calculation process of the traffic congestion determination device of the present embodiment. [Figure 4] 4 is an example of an operational flowchart relating to a driving mode selection process of the traffic congestion determination device of the present embodiment. [Figure 5] 4 is an example of an operational flowchart relating to a traffic congestion determination process of the traffic congestion determination device of the present embodiment. [Figure 6] FIG. 10 is a diagram illustrating a speed reference value set for each lane. [Figure 7] FIG. 10 is a diagram illustrating a traffic congestion determination process. [Figure 8] FIG. 10 is a diagram illustrating an example of a traffic congestion determination process. [Figure 9] FIG. 10 is a diagram illustrating another example of the traffic congestion determination process. [Figure 10] 10 is an example of an operational flowchart relating to branch road detection processing of the traffic congestion determination device. [Figure 11] 10A and 10B are diagrams illustrating a branch road detection process of the traffic congestion determination device. [Figure 12] 10 is an example of an operational flowchart relating to a merging road detection process of the congestion determination device. [Figure 13] 10A and 10B are diagrams illustrating a merging road detection process performed by the traffic congestion determination device. DETAILED DESCRIPTION OF THE INVENTION

[0017] 1 is a diagram illustrating an outline of the operation of a vehicle control system including a traffic congestion determination device 17 according to this embodiment. The traffic congestion determination device 17 is an example of a vehicle control device. Hereinafter, an outline of the operation related to the traffic congestion determination process of the traffic congestion determination device 17 disclosed in this specification will be described with reference to FIG. 1.

[0018] The vehicle 10 has an automatic control driving mode in which the vehicle 10 is driven under automatic control, and a manual control driving mode in which the driver operates and drives the vehicle. Currently, the vehicle 10 is controlled in the manual control driving mode, and the driver is driving the vehicle 10.

[0019] Vehicle 10 is traveling on lane 52 of road 50 having lanes 51, 52, and 53. Lanes 51 and 52 are separated by lane dividing line 54, and lanes 52 and 53 are separated by lane dividing line 55.

[0020] Lane 51 is the lane to the left of lane 52 in which vehicle 10 is traveling, and other vehicles 31 and 32 are traveling on lane 51. In lane 52 in which vehicle 10 is traveling, another vehicle 33 is located in front of vehicle 10, and another vehicle 34 is located behind vehicle 10. Lane 53 is an overtaking lane, and other vehicles 35 and 36 are traveling on lane 53.

[0021] The congestion determination device 17 of the vehicle 10 acquires vehicle state information of the vehicle 10 using a sensor mounted on the vehicle 10 and calculates the speed of the vehicle 10 traveling on the lane 52 .

[0022] In addition, the traffic congestion determination device 17 uses sensors mounted on the vehicle 10 to acquire information about the surrounding environment of the vehicle 10, and based on this information, determines the speed of other vehicles traveling in lanes 51, 52, and 53 within a predetermined range L from the vehicle 10.

[0023] The congestion determination device 17 calculates the average speed of the other vehicles 31 and 32 traveling on the lane 51 as the average vehicle speed of the lane 51. The congestion determination device 17 also calculates the average speed of the vehicle 10 and the other vehicles 33 and 34 traveling on the lane 52 as the average vehicle speed of the lane 52. The congestion determination device 17 also calculates the average speed of the other vehicles 35 and 36 traveling on the lane 53 as the average vehicle speed of the lane 53.

[0024] The congestion determination device 17 determines whether or not each of the three lanes 51, 52, and 53 of the road 50 is congested based on the average vehicle speed of the lane. In the example shown in Fig. 1, the congestion determination device 17 determines that each of the three lanes 51, 52, and 53 of the road 50 is congested.

[0025] Then, the congestion determination device 17 estimates whether the entire road 50 is congested based on the proportion of congested lanes in the travel road 50. In the example shown in Fig. 1, all lanes 51, 52, and 53 of the road 50 are congested, so the congestion determination device 17 estimates that the entire road 50 is congested.

[0026] Because the entire road 50 is congested, the congestion determination device 17 determines to drive the vehicle 10 under automatic control and selects to control the vehicle 10 in the automatic control driving mode. The congestion determination device 17 notifies the driver of the change from the manual control driving mode to the automatic control driving mode, and starts driving the vehicle 10 in the automatic control driving mode.

[0027] On the other hand, if the entire road 50 is not congested, the congestion determination device 17 selects to control the vehicle 10 in the manual control driving mode. The vehicle 10 continues to be driven in the current manual control driving mode.

[0028] For example, even if the average vehicle speed of lane 52 in which vehicle 10 is traveling is high, there may be a case where the average vehicle speed of lane 53, which is actually an overtaking lane, is decreasing, and congestion has begun on the entire road. In such a case, congestion determination device 17 can quickly detect the start of congestion on the entire road.

[0029] The congestion determination device 17 estimates the overall state of the road 50 based on the average vehicle speed of each of the multiple lanes 51, 52, and 53 of the road 50, so that the start of congestion on the entire road 50 can be quickly detected and the overall state of the road 50 can be appropriately reflected in the control of the vehicle 10.

[0030] 2 is a schematic configuration diagram of a vehicle 10 in which a vehicle control system 1 is implemented. The vehicle control system 1 includes cameras 2a and 2b, LiDAR sensors 3a and 3b, a positioning information receiver 4, a navigation device 5, a user interface (UI) 6, a map information storage device 11, a position estimation device 12, an object detection device 13, a driving lane planning device 14, a driving planning device 15, a vehicle control device 16, and a congestion determination device 17. Furthermore, the vehicle control system 1 may include other distance measurement sensors (not shown), such as a radar sensor, for measuring distances to objects around the vehicle 10.

[0031] The cameras 2a, 2b, LiDAR sensors 3a, 3b, positioning information receiver 4, navigation device 5, UI 6, map information storage device 11, position estimation device 12, object detection device 13, driving lane planning device 14, driving planning device 15, vehicle control device 16, and congestion determination device 17 are communicatively connected via an in-vehicle network 18 that complies with a standard such as a controller area network.

[0032] Cameras 2a and 2b are examples of imaging units provided on vehicle 10. Camera 2a is attached to vehicle 10 so as to face forward of vehicle 10. Camera 2b is attached to vehicle 10 so as to face rearward of vehicle 10. Each of cameras 2a and 2b captures camera images showing the environment of a predetermined area in front of or behind vehicle 10, for example, at a predetermined period. The camera images may show the road included in the predetermined area in front of or behind vehicle 10 and road features such as lane markings on the road surface. The camera image captured by camera 2a may show other vehicles located to the left, front, and right front of vehicle 10. The camera image captured by camera 2b may show other vehicles located to the left, rear, and right rear of vehicle 10. Cameras 2a and 2b have a two-dimensional detector consisting of an array of photoelectric conversion elements sensitive to visible light, such as a CCD or C-MOS, and an imaging optical system that forms an image of the area to be photographed on the two-dimensional detector.

[0033] Every time the cameras 2a and 2b capture a camera image, they output the camera image and the time at which the camera image was captured to the position estimation device 12, the object detection device 13, etc. via the in-vehicle network 18. The camera image is used by the position estimation device 12 in a process of estimating the position of the vehicle 10. The camera image is also used by the object detection device 13 in a process of detecting other objects around the vehicle 10.

[0034] Each of the LiDAR sensors 3a, 3b is attached to, for example, the exterior surface of the vehicle 10 so as to face the front or rear of the vehicle 10. Each of the LiDAR sensors 3a, 3b synchronously emits a pulsed laser beam toward the front or rear of the vehicle 10 at a reflected wave information acquisition time set at a predetermined cycle, and receives the reflected wave reflected by a reflecting object. The time required for the reflected wave to return contains distance information between the vehicle 10 and other objects located in the direction of the laser irradiation. Each of the LiDAR sensors 3a, 3b outputs reflected wave information including the laser irradiation direction and the time required for the reflected wave to return, together with the reflected wave information acquisition time at which the laser was emitted, to the object detection device 13 via the in-vehicle network 18. The reflected wave information is used by the object detection device 13 to detect other objects around the vehicle 10.

[0035] The positioning information receiver 4 outputs positioning information that indicates the current position of the vehicle 10. For example, the positioning information receiver 4 may be a GNSS receiver. Every time the positioning information receiver 4 acquires positioning information at a predetermined reception cycle, the positioning information receiver 4 outputs the positioning information and the time at which the positioning information was acquired to the navigation device 5, the map information storage device 11, etc.

[0036] The navigation device 5 generates a navigation route from the current position of the vehicle 10 to the destination position based on the navigation map information, the destination position of the vehicle 10 input from the UI 6, and the positioning information indicating the current position of the vehicle 10 input from the positioning information receiver 4. The navigation device 5 generates a new navigation route for the vehicle 10 when a new destination position is set or when the current position of the vehicle 10 deviates from the navigation route. Every time the navigation device 5 generates a navigation route, it outputs the navigation route to the position estimation device 12, the driving lane planning device 14, etc. via the in-vehicle network 18.

[0037] The UI 6 is an example of a notification unit. The UI 6 is controlled by the navigation device 5, the traffic congestion determination device 17, and the like to notify the driver of driving information of the vehicle 10, a control change notification notifying the driver that the driving of the vehicle 10 will be changed from manual control to automatic control, and the like. The UI 6 also generates an operation signal in response to an operation performed by the driver on the vehicle 10. The driving information of the vehicle 10 includes information about the current and future routes of the vehicle, such as the current location of the vehicle and a navigation route. The UI 6 has a display device 6a, such as a liquid crystal display or a touch panel, for displaying the driving information and the like. The UI 6 may also have an audio output device (not shown) for notifying the driver of the driving information and the like. The UI 6 also has, for example, a touch panel or an operation button as an input device for inputting operation information from the driver to the vehicle 10. Examples of the operation information include a destination location, intermediate destinations, vehicle speed, and other control information of the vehicle 10. The UI 6 outputs the input operation information to the navigation device 5, the vehicle control device 16, the traffic congestion determination device 17, and the like via the in-vehicle network 18.

[0038] The map information storage device 11 stores map information of a relatively wide area (e.g., a range of 10 to 30 km square) including the current position of the vehicle 10. This map information includes three-dimensional information about the road surface, information representing the types and positions of road features and structures such as lane markings on the road, and high-precision map information including the legal road speed limit. The map information storage device 11 receives wide-area map information from an external server via a base station through wireless communication via a wireless communication device (not shown) mounted on the vehicle 10 according to the current position of the vehicle 10, and stores the received map information in the storage device. Each time positioning information is input from the positioning information receiver 4, the map information storage device 11 refers to the stored wide-area map information and outputs map information of a relatively small area (e.g., a range of 100 m to 10 km square) including the current position represented by the positioning information to the position estimation device 12, object detection device 13, driving lane planning device 14, driving planner 15, vehicle control device 16, congestion determination device 17, etc. via the in-vehicle network 18.

[0039] The position estimation device 12 estimates the position of the vehicle 10 at the time the camera image was captured, based on road features around the vehicle 10 that are shown in the camera image captured by the camera 2a. For example, the position estimation device 12 compares lane markings identified in the camera image with lane markings shown in map information input from the map information storage device 11, to determine an estimated position and estimated azimuth angle of the vehicle 10 at the time the camera image was captured. The position estimation device 12 also estimates the driving lane on the road on which the vehicle 10 is located, based on the lane markings shown in the map information and the estimated position and estimated azimuth angle of the vehicle 10. Each time the position estimation device 12 determines the estimated position, estimated azimuth angle, and driving lane of the vehicle 10 at the time the camera image was captured, it outputs this information to the object detection device 13, the driving lane planning device 14, the driving planner 15, the vehicle control device 16, the congestion determination device 17, etc. The position estimation device 12 may estimate the position of the vehicle 10 based on two camera images taken by the camera 2a and the camera 2b.

[0040] The object detection device 13 detects other objects and their types in the left front, front, and right front of the vehicle 10 based on camera images captured by the camera 2a. The object detection device 13 also detects other objects and their types in the left rear, rear, and right rear of the vehicle 10 based on camera images captured by the camera 2b. The other objects include other vehicles traveling around the vehicle 10. The object detection device 13 has, for example, a classifier that receives a camera image as input and detects objects depicted in the image. The classifier may be, for example, a deep neural network (DNN) that is trained in advance to detect objects depicted in the input image. The object detection device 13 may also use a classifier other than a DNN. For example, the object detection device 13 may use, as the classifier, a support vector machine (SVM) that is trained in advance to receive input features (e.g., histograms of oriented gradients, HOG) calculated from a window set on the camera image and output a confidence level that the object to be detected is depicted in the window. Alternatively, the object detection device 13 may detect an object region by performing template matching between a template representing the object to be detected and the image.

[0041] The object detection device 13 detects other objects to the left, front, and right of the vehicle 10 based on the reflected wave information output by the LiDAR sensor 3a, and detects other objects to the left, rear, and right of the vehicle 10 based on the reflected wave information output by the LiDAR sensor 3b. The object detection device 13 determines the orientation of the other object relative to the vehicle 10 based on the position of the other object in the camera image, and determines the distance between the other object and the vehicle 10 based on this orientation and the reflected wave information output by the LiDAR sensors 3a and 3b. The object detection device 13 estimates the position of the other object, expressed in, for example, a world coordinate system, based on the current position of the vehicle 10 and the distance and orientation of the other object relative to the vehicle 10. The object detection device 13 also tracks the other object detected in the latest camera image by associating the other object with objects detected in past images according to a tracking process based on optical flow. The object detection device 13 then determines the trajectory of the other object being tracked based on the position of the object in the world coordinate system in the most recent image from past images. The object detection device 13 estimates the speed of the other object relative to the vehicle 10 based on changes in the position of the other object over time. The object detection device 13 can also estimate the acceleration of the other object based on changes in the speed of the other object over time. The object detection device 13 also identifies the lane in which the other object is traveling based on lane markings shown in the map information and the position of the other object. For example, the object detection device 13 determines that the other object is traveling in a lane identified by two adjacent lane markings located on either side of the horizontal center position of the other object. The object detection device 13 outputs object detection information, including information indicating the type of the detected other object, information indicating its position, speed, acceleration, and traveling lane, to the lane planning device 14, the driving planner 15, the vehicle control device 16, the congestion determination device 17, etc. The detection range in which the object detection device 13 can detect other objects is determined based on the installation conditions, resolution, etc. of the cameras 2a and 2b and the LiDAR sensors 3a and 3b.

[0042] At a travel lane plan generation time set at a predetermined cycle, the travel lane planning device 14 selects lanes within the road on which the vehicle 10 will travel, based on map information, the navigation route, surrounding environment information, and the current position of the vehicle 10, for the nearest driving section (e.g., 10 km) selected from the navigation route, and generates a travel lane plan that indicates the planned travel lane on which the vehicle 10 will travel. The travel lane planning device 14 generates a travel lane plan, for example, so that the vehicle 10 will travel in a lane other than an overtaking lane. Every time the travel lane planning device 14 generates a travel lane plan, it outputs the travel lane plan to the driving planning device 15.

[0043] Furthermore, the driving lane planning device 14 determines whether a lane change is necessary for the nearest driving section selected from the navigation route, based on the driving lane plan, map information, the navigation route, and the current position of the vehicle 10, and generates a lane change plan based on the determination result. The lane change plan includes a planned lane change section in which the vehicle 10 is scheduled to move to an adjacent lane on the lane on which the vehicle 10 is traveling. Specifically, the driving lane planning device 14 determines whether a lane change is necessary to move to a lane leading to the destination of the vehicle 10, based on the navigation route and the current position of the vehicle 10. The driving lane planning device 14 determines whether the vehicle 10 will enter from the driving road on which the vehicle 10 is currently traveling onto another road at a merging destination (merging), and whether the vehicle 10 will exit from the driving road to another road at a branching destination (branching). At merging and branching, the vehicle moves from a lane on the driving road to a lane on another road, so a lane change is performed. The driving lane planning device 14 may further use surrounding environment information or vehicle state information to determine whether a lane change is necessary. The surrounding environment information includes the positions and speeds of other vehicles traveling around the vehicle 10. The vehicle state information includes the current position, vehicle speed, acceleration, and traveling direction of the vehicle 10. The driving lane planning device 14 also generates a lane change plan in response to a driver's request. Information representing the vehicle speed and acceleration of the vehicle 10 is acquired using sensors (not shown) mounted on the vehicle 10.

[0044] The driving planner 15 executes a driving plan process to generate a driving plan representing a planned driving trajectory of the vehicle 10 up to a predetermined time (for example, 5 seconds) ahead based on a driving lane plan, map information, the current position of the vehicle 10, surrounding environment information, and vehicle state information at a driving plan generation time set at a predetermined cycle. The driving plan is expressed as a set of target positions of the vehicle 10 and target vehicle speeds at these target positions at each time from the current time to the predetermined time ahead. The cycle in which the driving plan is generated is preferably shorter than the cycle in which the driving lane plan is generated. The driving planner 15 generates a driving plan so that a gap of at least a predetermined distance can be maintained between the vehicle 10 and other vehicles. Every time the driving plan is generated, the driving planner 15 outputs the driving plan to the vehicle control device 16.

[0045] The vehicle control device 16 has an automatic control driving mode in which the vehicle 10 is driven automatically, and a manual control driving mode in which the driver operates the vehicle. When the automatic control driving mode is applied, the vehicle control device 16 can automatically control all vehicle operations, including driving, braking, and steering, based on a driving plan.

[0046] When the vehicle 10 is driven in the automatic control driving mode, the vehicle control device 16 controls each part of the vehicle 10 based on the current position, vehicle speed, yaw rate, and driving plan generated by the driving planner 15. For example, the vehicle control device 16 calculates the steering angle, acceleration, and angular acceleration of the vehicle 10 according to the driving plan, the vehicle speed, and yaw rate of the vehicle 10, and sets the steering amount, accelerator opening, or braking amount so as to achieve the steering angle, acceleration, and angular acceleration. The vehicle control device 16 then outputs a control signal corresponding to the set steering amount to an actuator (not shown) that controls the steered wheels of the vehicle 10 via the in-vehicle network 18. The vehicle control device 16 also calculates a fuel injection amount according to the set accelerator opening, and outputs a control signal corresponding to the fuel injection amount to a drive device (not shown) such as an engine of the vehicle 10 via the in-vehicle network 18. Alternatively, the vehicle control device 16 outputs a control signal corresponding to the set braking amount to a brake (not shown) of the vehicle 10 via the in-vehicle network 18.

[0047] On the other hand, in the manual control driving mode, the driver can operate the vehicle manually using the steering wheel, accelerator pedal, brake pedal (not shown), etc. When the vehicle 10 is driven manually, the vehicle control device 16 controls the steering wheels, drive unit, or brakes according to the steering amount, accelerator opening, or braking amount operated by the driver. In the manual control driving mode, at least one of the driving, braking, and steering operations of the vehicle 10 is manually controlled. It is also possible to switch from automatic control to manual control according to the driver's request.

[0048] When the vehicle control device 16 in the automatic control driving mode determines that the vehicle 10 cannot be driven safely under automatic control, and if the driver approves a control change notification requesting a change from automatic control to manual control, the vehicle control device 16 switches the driving of the vehicle 10 from the automatic control driving mode to the manual control driving mode. In a situation where the vehicle 10 cannot be driven safely under automatic control, the driver drives the vehicle by operating it under manual control using the steering wheel, accelerator pedal, brake pedal (not shown), etc. The driver may also switch the driving of the vehicle 10 from the automatic control driving mode to the manual control driving mode by notifying the vehicle control device 16 of a control change request requesting a change from automatic control to manual control.

[0049] When the vehicle control device 16 in the manual control driving mode estimates that the entire road on which the vehicle 10 is traveling is congested, it notifies the driver of a control change notification proposing a change from manual control to automatic control. If this control change notification is accepted by the driver, the vehicle control device 16 switches the driving of the vehicle 10 from the currently applied manual control driving mode to the automatic control driving mode. As a result, when the road is congested, the vehicle control device 16 controls the driving of the vehicle, and the driver is relieved from driving the vehicle.

[0050] The congestion determination device 17 executes a speed calculation process, a state estimation process, and a decision process. To this end, the congestion determination device 17 has a communication interface (IF) 21, a memory 22, and a processor 23. The communication interface 21, the memory 22, and the processor 23 are connected via a signal line 24. The communication interface 21 has an interface circuit for connecting the congestion determination device 17 to the in-vehicle network 18.

[0051] Some or all of the functions of the traffic congestion determination device 17 are functional modules implemented by a computer program running on the processor 23. The processor 23 includes a speed calculation unit 230, a state estimation unit 231, and a selection unit 232. Alternatively, the functional modules of the processor 23 may be dedicated arithmetic circuits provided in the processor 23. The processor 23 includes one or more central processing units (CPUs) and their peripheral circuits. The processor 23 may further include other arithmetic circuits such as a logic unit, a numerical calculation unit, or a graphics processing unit. The memory 22 is an example of a storage unit and includes, for example, a volatile semiconductor memory and a nonvolatile semiconductor memory. The memory 22 stores computer programs and various data for applications used in information processing executed by the processor 23. Other operations of the traffic congestion determination device 17 will be described in detail later.

[0052] In FIG. 2, the map information storage device 11, the position estimation device 12, the object detection device 13, the driving lane planning device 14, the driving planning device 15, the vehicle control device 16, and the congestion determination device 17 are described as separate devices, but all or some of these devices may be configured as a single device.

[0053] Fig. 3 is an example of an operational flowchart relating to the average vehicle speed calculation process of the congestion determination device 17 of this embodiment. The average vehicle speed calculation process of the congestion determination device 17 will be described below with reference to Fig. 3. The congestion determination device 17 executes the average vehicle speed calculation process in accordance with the operational flowchart shown in Fig. 3 at average vehicle speed calculation times having a predetermined cycle.

[0054] First, the speed calculation unit 230 acquires, as surrounding environment information, the speeds of other vehicles traveling on each of the lanes of the road on which the vehicle 10 is traveling, from the object detection device 13 (step S101). In addition, the speed calculation unit 230 acquires, as vehicle state information, information indicating the speed of the vehicle 10 from a sensor (not shown) mounted on the vehicle 10.

[0055] Next, the speed calculation unit 230 calculates the average vehicle speed of the lanes within a predetermined range L from the vehicle 10 for each of the lanes of the road on which the vehicle 10 is traveling, and ends the series of processes (step S102). The speed calculation unit 230 acquires the number of lanes of the road on which the vehicle 10 is traveling based on map information. The speed calculation unit 230 also acquires the speeds of other vehicles traveling in each of the lanes of the road on which the vehicle 10 is traveling from the object detection device 13. The predetermined range L corresponds to the detection range in which the object detection device 13 can detect other vehicles.

[0056] The speed calculation unit 230 calculates the average value of the speeds of other vehicles traveling on lanes other than the lane on which the vehicle 10 is traveling as the average vehicle speed of the lane. Furthermore, the speed calculation unit 230 calculates the average value of the speeds of the vehicle 10 and other vehicles traveling on the lane on which the vehicle 10 is traveling as the average vehicle speed of the lane. Note that the speed calculation unit 230 may use the most recent average speed of each vehicle as the speed of the vehicle 10 and the other vehicles. The most recent average speed is, for example, the average speed over the last 5 to 10 seconds. Note that when the road on which the vehicle 10 is traveling has only one lane, the speed calculation unit 230 calculates the average vehicle speed of the lane on which the vehicle 10 is traveling.

[0057] Fig. 4 is an example of an operational flowchart relating to the driving mode selection process of the traffic congestion determination device 17 of this embodiment. Hereinafter, the driving mode selection process of the traffic congestion determination device 17 will be described with reference to Fig. 4. When the vehicle 10 is being driven in manual control driving mode, the traffic congestion determination device 17 executes vehicle control processing in accordance with the operational flowchart shown in Fig. 4 at driving mode selection times having a predetermined cycle. It is preferable that the cycle of the driving mode selection times be the same as or longer than the cycle of the average vehicle speed calculation times described above.

[0058] First, the state estimation unit 231 determines whether or not each of the multiple lanes of the road on which the vehicle 10 is traveling is congested based on the average vehicle speed of the lane (step S201). Of the lanes other than the lane on which the vehicle 10 is traveling, the state estimation unit 231 determines that a lane on which no other vehicles are traveling is not congested. Note that if the road on which the vehicle 10 is traveling has only one lane, the state estimation unit 231 determines whether or not the lane on which the vehicle 10 is traveling is congested. Details of the congestion determination process by the state estimation unit 231 will be described later.

[0059] Next, the state estimation unit 231 calculates the proportion P of congested lanes on the road on which the vehicle 10 is traveling (step S202). For example, the state estimation unit 231 calculates the product (n / m*100) of 100 and the value obtained by dividing the number n of lanes determined to be congested among the lanes on the road on which the vehicle 10 is traveling by the number m of lanes on the road on which the vehicle 10 is traveling (n / m), as the proportion P of congested lanes.

[0060] Next, the state estimation unit 231 estimates whether the entire road is congested based on the proportion P of congested lanes on the road on which the vehicle 10 is traveling (step S203). If the proportion P of congested lanes on the road on which the vehicle 10 is traveling is equal to or greater than a predetermined reference proportion, the state estimation unit 231 determines that the entire road is congested. The predetermined reference proportion may be, for example, 50%. Note that the predetermined reference proportion may also be another numerical value.

[0061] Furthermore, the state estimation unit 231 may change the predetermined reference rate based on the most recent average speed of the vehicle 10. If the average speed of the vehicle 10 is faster than the predetermined reference rate, the predetermined reference rate (for example, 50%) may be changed to be reduced. On the other hand, if the average speed of the vehicle 10 is slower than the predetermined reference rate, the predetermined reference rate (for example, 50%) may be changed to be increased.

[0062] If the entire road is congested (step S203-Yes), the decision unit 232 decides to drive the vehicle 10 under automatic control (step S204). The decision unit 232 selects to drive the vehicle 10 in the automatic control driving mode. Since the vehicle 10 is currently being driven in the manual control driving mode, the decision unit 232 notifies the driver via the UI 6 of a control change notification proposing a change from manual control to automatic control. If the driver accepts this control change notification via the UI 6, the decision unit 232 controls the vehicle control device 16 to start driving the vehicle 10 in the automatic control driving mode (step S206). Note that if the driver does not accept this control change notification via the UI 6, the vehicle control device 16 continues to control the vehicle 10 in the current manual control driving mode.

[0063] On the other hand, if the entire road is not congested (step S203-No), the decision unit 232 decides to drive the vehicle 10 under manual control (step S205). The decision unit 232 selects to control the vehicle 10 in the manual control driving mode.

[0064] The vehicle control device 16 continues the state in which the vehicle 10 is controlled in the current manual control driving mode (step S206).

[0065] 5 is an example of an operational flowchart relating to the congestion determination process of the congestion determination device 17 of this embodiment. Hereinafter, the congestion determination process by the state estimation unit 231 will be described with reference to FIG.

[0066] First, the state estimation unit 231 determines whether or not the average vehicle speed of each of the multiple lanes of the road 50 on which the vehicle 10 is traveling is equal to or less than a speed reference value set for each lane (step S301).

[0067] If the average vehicle speed of the lane is equal to or less than the speed reference value set for each lane (step S301-Yes), the state estimation unit 231 determines that this lane is congested (step S302).

[0068] On the other hand, if the average vehicle speed of the lane is not equal to or less than the speed reference value set for each lane (step S301-No), the state estimation unit 231 determines that this lane is not congested (step S303).

[0069] Fig. 6 is a diagram illustrating the speed reference value set for each lane. When the road 50 on which the vehicle 10 is traveling has three lanes 51, 52, and 53, as in the example shown in Fig. 1, the state estimation unit 231 sets a reference decrease amount for each of the left lane 51, the center lane 52, and the overtaking lane 53. The state estimation unit 231 sets the reference decrease amount at a reference decrease amount setting time having a predetermined reference decrease amount setting period (which is an example of a predetermined reference time).

[0070] The state estimation unit 231 sets a speed reference value for each lane, for the left lane 51, the center lane 52, and the overtaking lane 53, based on the average value of the average vehicle speed of the lane during the reference decrease amount setting cycle. The state estimation unit 231 acquires the average vehicle speed of the lane during the reference decrease amount setting cycle from the speed calculation unit 230 and calculates the average value of the average vehicle speed of the lane. It is preferable that the reference decrease amount is set to be larger as the average value of the average vehicle speed of the lane increases. In the example shown in FIG. 6, the reference decrease amount is set to be 30% of the average value of the average vehicle speed of the lane. Note that the ratio of the reference decrease amount to the average value of the average vehicle speed of the lane is not limited to this example.

[0071] The reference decrease amount setting period may be a fixed time. The fixed time may be, for example, 5 to 10 minutes. The reference decrease amount setting period may also be determined by changing the fixed time based on the most recent average speed of the vehicle 10. In this case, the reference decrease amount setting period may be changed so that the fixed time becomes longer as the most recent average speed of the vehicle 10 becomes slower.

[0072] The state estimation unit 231 sets the value obtained by subtracting the reference decrease amount from the average vehicle speed of each of the left lane 51, center lane 52, and overtaking lane 53 as the speed reference value for that lane.

[0073] Fig. 7 is a diagram illustrating the congestion determination process. As shown in the example of Fig. 6, the road on which vehicle 10 is traveling has a left lane, a center lane, and an overtaking lane, and the average vehicle speed in the left lane is 50 km / h (13.8 m / s), the average vehicle speed in the center lane is 70 km / h (19.4 m / s), and the average vehicle speed in the overtaking lane is 90 km / h (25 m / s). Here, it is assumed that the road is congested 1 km ahead from the current position of vehicle 10, and the average vehicle speed on the entire road there is 30 km / h (8.3 m / s).

[0074] As shown in FIG. 7, the change in average vehicle speed of each lane from the current position of the vehicle 10 to 1 km ahead increases in the order of the left lane, center lane, and overtaking lane. In other words, the change in average vehicle speed of a lane increases as the average vehicle speed at the current position of the vehicle 10 increases. Therefore, it is believed that the occurrence of congestion can be detected earlier by focusing on the speed change in the lane with a faster average vehicle speed. Therefore, as described above, the magnitude of the reference decrease amount is set to increase as the average vehicle speed of the lane increases. Usually, the magnitude of the reference decrease amount increases in the order of the left lane, center lane, and overtaking lane.

[0075] A specific example of the operation of the congestion determination device 17 will be described below with reference to FIGS.

[0076] In the example shown in FIG. 1 , the state estimation unit 231 determines that each of the three lanes 51, 52, and 53 of the road 50 is congested. The state estimation unit 231 determines that the entire road is congested because the proportion P (100%) of congested lanes on the road on which the vehicle 10 is traveling is equal to or greater than a predetermined reference proportion (e.g., 50%). Because the entire road 50 is congested, the decision unit 232 decides to drive the vehicle 10 under automatic control and selects to control the vehicle 10 in the automatic control driving mode. The decision unit 232 notifies the driver of a change from the manual control driving mode to the automatic control driving mode and controls the vehicle control device 16 to start controlling the vehicle 10 in the selected automatic control driving mode. The congestion determination device 17 estimates the state of the entire road based on the average vehicle speed of each of the multiple lanes on the road on which the vehicle is traveling, and can quickly detect the start of congestion on the entire road and reflect this in the control of the vehicle 10.

[0077] In the example shown in FIG. 8 , the state estimation unit 231 determines that, of the three lanes 51, 52, and 53 of the road 50, lanes 51 and 53 are congested, and determines that lane 52 on which the vehicle 10 is traveling is not congested. The state estimation unit 231 determines that the entire road is congested because the proportion P (67%) of congested lanes on the road on which the vehicle 10 is traveling is equal to or greater than a predetermined reference proportion (e.g., 50%). Because the entire road 50 is congested, the decision unit 232 decides to drive the vehicle 10 under automatic control and selects to control the vehicle 10 in the automatic control driving mode. The decision unit 232 notifies the driver of a change from the manual control driving mode to the automatic control driving mode, and controls the vehicle control device 16 to start controlling the vehicle 10 in the selected automatic control driving mode. Even if the lane 52 on which the vehicle 10 is traveling is not congested, the other lanes 51 and 53 are congested, so the congestion determination device 17 estimates that the entire road 50 is congested, thereby quickly detecting the start of congestion on the entire road and reflecting this in the control of the vehicle 10.

[0078] In the example shown in FIG. 9 , the state estimation unit 231 determines that, of the three lanes 51, 52, and 53 of the road 50, the lane 52 on which the vehicle 10 is traveling is congested, and determines that the lanes 51 and 53 are not congested. The state estimation unit 231 determines that the entire road is not congested because the proportion P (33%) of congested lanes on the road on which the vehicle 10 is traveling is less than a predetermined reference proportion (e.g., 50%). The decision unit 232 selects to control the vehicle 10 in the manual control driving mode because the entire road 50 is not congested. The vehicle control device 16 continues the state in which the vehicle 10 is controlled in the current manual control driving mode. Even if the lane 52 on which the vehicle 10 is traveling is congested, the lanes 51 and 53 are not congested. Therefore, the congestion determination device 17 estimates that the entire road is not congested, thereby accurately detecting the overall road condition and reflecting this in the control of the vehicle 10.

[0079] As described above, the vehicle control device of this embodiment estimates the overall road condition based on the average vehicle speed of each of the multiple lanes on the road on which the vehicle is traveling, so that the overall road condition can be appropriately reflected in the control of the vehicle.

[0080] In the above-described embodiment, the speed reference value used by the state estimation unit 231 when determining whether a lane is congested is fixed. However, if there is a branch location where another road (e.g., a branch road leading to an interchange exit or a junction) from which other vehicles can exit the road on which the vehicle 10 is traveling branches off, it is expected that the average vehicle speed of the lane will increase as other vehicles exit onto the branch road. In this case, if the speed reference value is fixed, there is a risk that the overall road conditions will not be accurately detected. Therefore, as described below, the vehicle control device may change the reference decrease amount when there is a branch road ahead of the current position of the vehicle 10.

[0081] 10 is an example of an operational flowchart relating to branch road detection processing by the traffic congestion determination device 17. The traffic congestion determination device 17 executes the branch road detection processing shown in FIG. 10 at branch road detection times having a predetermined cycle.

[0082] First, the state estimation unit 231 determines whether the branch position is within a predetermined range M (e.g., 5 km) from the current position of the vehicle 10 in the traveling direction based on the current position of the vehicle 10 and map information (step S401).

[0083] 11 is a diagram illustrating the branch road detection process of the congestion determination device 17. A branch position 61 where a branch road 60 branches off from a road 50 is within a first range M from the current position of the vehicle 10 in the traveling direction. At the branch position 61, another vehicle 31 can exit the road 50.

[0084] If the branch position is within a predetermined range M from the current position of the vehicle 10 in the direction of travel (step S401-Yes), the state estimation unit 231 increases the speed reference value for each of the multiple lanes of the road on which the vehicle 10 is traveling, and ends the series of processes (step S402).

[0085] On the other hand, if the branch position is not within the predetermined range M from the current position of the vehicle 10 in the traveling direction (step S401-No), the state estimation unit 231 ends the series of processes (step S403).

[0086] After the vehicle 10 passes the branch point, the state estimation unit 231 returns the speed reference value to the original value before the increase.

[0087] Furthermore, if there is a merging location where another road (for example, a merging road leading to an interchange entrance or a junction) from which other vehicles can enter the road on which vehicle 10 is traveling merges into the road on which vehicle 10 is traveling, it is expected that the average vehicle speed of the lane will decrease when the other vehicle enters the road on which vehicle 10 is traveling from the merging road. In this case, if the reference decrease amount is fixed, there is a risk that the overall road conditions will not be accurately detected. Therefore, as will be described below, the vehicle control device may change the reference decrease amount when there is a merging road ahead of the current position of vehicle 10.

[0088] 12 is an example of an operational flowchart relating to the merging road detection process of the congestion determination device 17. The congestion determination device 17 executes the merging road detection process shown in FIG. 12 at the merging road detection time having a predetermined cycle.

[0089] First, the state estimation unit 231 determines whether the merging position is within a predetermined range (e.g., 5 km) from the current position of the vehicle 10 in the traveling direction based on the current position of the vehicle 10 and map information (step S501).

[0090] 13 is a diagram illustrating the merging road detection process of the congestion determination device 17. A merging position 71 where a merging road 70 merges with a road 50 is within a predetermined range N in the traveling direction from the current position of the vehicle 10. At the merging position 71, another vehicle 31 can enter the road 50.

[0091] If the merging position is within a predetermined range from the current position of the vehicle 10 (step S501-Yes), the state estimation unit 231 reduces the reference reduction amount for each of the multiple lanes of the road on which the vehicle 10 is traveling, and ends the series of processes (step S502).

[0092] On the other hand, if the merging position is not within the predetermined range from the current position of the vehicle 10 (step S501-No), the state estimation unit 231 ends the series of processes (step S503).

[0093] After the vehicle 10 passes the merging point, the state estimation unit 231 returns the speed reference value to the original value before the reduction.

[0094] In the present disclosure, the vehicle control device, the vehicle control computer program, and the vehicle control method of the above-described embodiments can be modified as appropriate without departing from the spirit of the present disclosure. Furthermore, the technical scope of the present disclosure is not limited to those embodiments, but extends to the inventions set forth in the claims and their equivalents. [Explanation of symbols]

[0095] 1. Vehicle control system 2a, 2b cameras 3a, 3b LiDAR sensor 4. Positioning information receiver 5. Navigation devices 6 User Interface 6a Display device 10 vehicles 11 Map information storage device 12 Position estimation device 13 Object detection device 14. Lane planning device 15 Operation planning device 16 Vehicle control device 17. Traffic congestion detection device 18 In-vehicle network 21 Communication Interface 22 Memory 23 processors 230 Speed ​​calculation section 231 State Estimation Unit 232 Decision Section

Claims

1. a speed calculation unit that calculates, for each of a plurality of lanes of a road on which a vehicle is traveling, an average speed of the vehicle traveling on that lane or other vehicles within a predetermined range from the vehicle as the average vehicle speed of that lane; a state estimation unit that determines whether or not each of a plurality of lanes of the travel road is congested based on an average vehicle speed of the lane, and estimates whether or not the entire travel road is congested based on a ratio of congested lanes within the travel road; a decision unit that decides to drive the vehicle under automatic control when the entire road is congested; and the state estimation unit sets a speed reference value for each of a plurality of lanes of the road based on an average value of the average vehicle speed of the lane during a predetermined reference time, and determines that the lane is congested when the average vehicle speed of the lane is equal to or less than the speed reference value set for the lane.

2. 2. The vehicle control device according to claim 1, wherein when a branch position where another road branches off from the travel road is within a first range from the current position of the vehicle in the direction of travel, the state estimation unit increases the speed reference value for each of a plurality of lanes of the travel road.

3. 3. The vehicle control device according to claim 1, wherein when a merging position where another road merges into the traveled road is within a second range from a current position of the vehicle in a traveling direction, the state estimation unit reduces the speed reference value for each of a plurality of lanes of the traveled road.

4. For each of a plurality of lanes of a road on which the vehicle is traveling, an average speed of the vehicle traveling on that lane or other vehicles within a predetermined range from the vehicle is calculated as the average vehicle speed of that lane; For each of a plurality of lanes of the travel road, it is determined whether or not the lane is congested based on an average vehicle speed of the lane, and it is estimated whether or not the entire travel road is congested based on the proportion of lanes that are congested within the travel road; When the entire road is congested, determining to drive the vehicle under automatic control. causing a processor to execute a speed reference value is set for each of a plurality of lanes of the road based on an average value of the average vehicle speed of the lane during a predetermined reference time, and if the average vehicle speed of each of the plurality of lanes of the road is equal to or less than the speed reference value set for the lane, the lane is determined to be congested.

5. For each of a plurality of lanes of a road on which the vehicle is traveling, an average speed of the vehicle traveling on that lane or other vehicles within a predetermined range from the vehicle is calculated as the average vehicle speed of that lane; For each of a plurality of lanes of the travel road, it is determined whether or not the lane is congested based on an average vehicle speed of the lane, and it is estimated whether or not the entire travel road is congested based on the proportion of lanes that are congested within the travel road; When the entire road is congested, determining to drive the vehicle under automatic control; A vehicle control method characterized in that a vehicle control device executes the following: for each of a plurality of lanes of the travel road, a speed reference value is set for that lane based on the average value of the average vehicle speed of that lane over a predetermined reference time period; and for each of a plurality of lanes of the travel road, if the average vehicle speed of that lane is equal to or less than the speed reference value set for that lane, the lane is determined to be congested.

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