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

Abstract

To provide a vehicle control device that can enhance the level of safety at takeover of driving control assignment of a vehicle from the vehicle control device to a driver.SOLUTION: A vehicle control device includes: a determination unit 31 that determines whether or not to transfer a driving control assignment of a vehicle 10 under autonomous driving control to a driver; a notification processing unit 32 that notifies the driver of a transition demand via a notification device 5 in the case where the driving control assignment will be transferred to the driver; a control unit 33 that executes deceleration control of the vehicle 10 at predetermined timing after notification timing of the transition demand, and continues deceleration control of the vehicle 10 even after a predetermined period from the notification timing in the case where speed of the vehicle 10 decreases to a predetermined speed threshold or less within the predetermined period and where operation by the driver to take over the driving is not detected.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a vehicle control device for controlling the running of a vehicle, a vehicle control method, and a computer program for vehicle control. [Background technology]

[0002] During automatic driving control of a vehicle, if it becomes difficult to continue the automatic driving control for some reason, the subject of driving control of the vehicle may be transferred from the control device of the vehicle to the driver. In such a case, techniques have been proposed for smoothly transferring the subject of driving control (see Patent Documents 1 to 3).

[0003] The vehicle control device disclosed in Patent Document 1 performs state change control to change the state of the host vehicle when driving control is handed over from automatic to manual based on the driving environment of the host vehicle, or when it is predicted that the driving control will be handed over. As the state change control, the vehicle control device sets the acceleration or deceleration of the host vehicle to a value lower than the set value in the acceleration control or deceleration control when the state change control is not being performed.

[0004] Furthermore, the control device for an autonomous vehicle disclosed in Patent Document 2 transitions from the autonomous driving mode to the manual driving mode in response to the operation of any one of the steering operation member, the brake operation member, or the accelerator operation member before the second brake device that decelerates the vehicle starts decelerating in the autonomous driving mode. Furthermore, in the autonomous driving mode, this control device transitions from the autonomous driving mode to the manual driving mode in response to the operation of any one of the steering operation member or the accelerator operation member during the period from the start of deceleration by the second brake device until the first brake device that maintains the vehicle stopped state automatically operates.

[0005] The automated driving support device disclosed in Patent Document 3 sets a level indicating whether or not it is possible to switch from automated driving to manual driving in a predetermined switching section in a stepwise manner based on the driver's state. Furthermore, this automated driving support device reduces the vehicle's travel speed in all or part of the switching section during automated driving according to the set level. Then, when the reduced travel speed falls below the minimum speed, this automated driving support device issues a warning to the driver or automatically stops the vehicle in an evacuation area. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2018 / 109868 [Patent Document 2] JP 2018-144740 A [Patent Document 3] JP 2017-97518 A Summary of the Invention [Problem to be solved by the invention]

[0007] When the subject of driving control of the vehicle is handed over from the control device to the driver, the control device notifies the driver of a driving change request for handing over the subject of driving control from the control device to the driver. However, if the driver does not take over driving of the vehicle even after a certain period of time has passed since the notification of the driving change request, the safety of the vehicle may be compromised.

[0008] Therefore, an object of the present invention is to provide a vehicle control device that can improve safety when the main control of driving of the vehicle is handed over from the vehicle control device to the driver. [Means for solving the problem]

[0009] According to one embodiment, a vehicle control device is provided. The vehicle control device includes a determination unit that determines whether or not to transfer the subject of the driving control of the vehicle to the driver in an automatic driving control vehicle, a notification processing unit that notifies the driver of a request for a driving changeover via a notification device provided in the vehicle when the subject of the driving control of the vehicle is transferred to the driver, and a control unit that controls the deceleration of the vehicle at a predetermined timing after the notification timing at which the request for the driving changeover is notified, and continues the deceleration control of the vehicle even after the predetermined period has elapsed if the speed of the vehicle becomes equal to or lower than a predetermined speed threshold before a predetermined period has elapsed from the notification timing and a driving changeover operation by the driver is not detected.

[0010] In this vehicle control device, it is preferable that the control unit stops automatic driving control of the vehicle when a predetermined period of time has elapsed from the notification timing if the vehicle speed does not fall below a predetermined speed threshold and if the driver's operation to take over driving is not detected.

[0011] In this case, it is preferable that the control unit determines that the driver has taken over driving when it detects the driver steering the vehicle, or the driver maintaining the steering wheel while operating the accelerator or brake, until a predetermined period of time has elapsed from the notification timing, and on the other hand, determine that the driver has taken over driving when it detects the driver steering the vehicle, or the driver maintaining the steering wheel while operating the accelerator or brake.

[0012] Alternatively, when the vehicle speed is below a predetermined speed threshold, the control unit continues deceleration control of the vehicle unless an accelerator or brake operation by the driver as a driver's handover operation is detected, while when the vehicle speed is higher than the predetermined speed threshold, it preferably stops automatic driving control of the vehicle when a steering operation by the driver as a driver's handover operation or a predetermined operation including the driver holding the steering wheel is detected.

[0013] Furthermore, the control unit preferably adjusts the predetermined speed threshold depending on the gradient of the road on which the vehicle is traveling.

[0014] Alternatively, it is preferable that the control unit determines, depending on the reason for the decision to transfer control of the vehicle to the driver or the conditions around the vehicle, whether or not there is a risk of the vehicle colliding with another object due to the acceleration of the vehicle after transferring control of the vehicle to the driver, and continues deceleration control of the vehicle even after a specified period has elapsed only if it determines that there is such a risk.

[0015] According to another embodiment, a vehicle control method is provided, which includes: determining whether or not to transfer the subject of the driving control of the vehicle to the driver in a vehicle under automatic driving control; notifying the driver of a request for a driver change via a notification device provided in the vehicle when the subject of the driving control of the vehicle is to be transferred to the driver; controlling the vehicle to decelerate at a predetermined timing after the notification timing when the request for the driver change is notified; and continuing the deceleration control of the vehicle even after the predetermined period has elapsed if the speed of the vehicle becomes equal to or lower than a predetermined speed threshold before a predetermined period has elapsed from the notification timing and the driver's operation to take over the driving is not detected.

[0016] According to yet another embodiment, a computer program for controlling a vehicle is provided. The computer program for controlling a vehicle includes instructions for causing a processor mounted on the vehicle to execute the following: in a vehicle under automatic driving control, determine whether or not to transfer the subject of driving control of the vehicle to a driver; when transferring the subject of driving control of the vehicle to the driver, notify the driver of a request for a change of driving via a notification device provided on the vehicle; when a predetermined timing after the notification timing of the request for a change of driving is notified, decelerate the vehicle; and, when the speed of the vehicle becomes equal to or lower than a predetermined speed threshold by the time a predetermined period has elapsed from the notification timing and the driver's operation to take over driving is not detected, continue the deceleration control of the vehicle even after the predetermined period has elapsed. Effect of the Invention

[0017] The vehicle control device according to the present disclosure has an effect of improving safety when the main driving control of the vehicle is handed over from the vehicle control device to the driver. [Brief description of the drawings]

[0018] [Figure 1] 1 is a schematic configuration diagram of a vehicle control system in which a vehicle control device is implemented. [Diagram 2] 1 is a hardware configuration diagram of an electronic control device that is an embodiment of a vehicle control device. [Diagram 3] FIG. 2 is a functional block diagram of a processor of an electronic control unit related to vehicle control processing. [Figure 4] 1A is a schematic diagram showing the duration of autonomous driving control when the vehicle speed does not fall below a predetermined speed threshold within a predetermined period of time from the notification timing, and FIG. 1B is a schematic diagram showing the duration of autonomous driving control including deceleration control when the vehicle speed falls below a predetermined speed threshold within a predetermined period of time from the notification timing. [Diagram 5] 4 is an operation flowchart of a vehicle control process. [Figure 6] 10 is an operation flowchart of a vehicle control process according to a modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, a vehicle control device, a vehicle control method executed on the vehicle control device, and a computer program for vehicle control will be described with reference to the drawings. When the vehicle control device transfers the subject of the driving control of the vehicle to the driver for some reason, it executes deceleration control to decelerate the vehicle at a certain deceleration at a predetermined timing. Here, when the vehicle control device transfers the subject of the driving control to the driver and stops the deceleration control after a certain period of time has passed since the notification of a driving change request (Transition Demand, TD), the vehicle may accelerate due to a creep phenomenon or the like depending on the speed of the vehicle. In addition, it becomes difficult to achieve deceleration by engine braking. As a result, there is a risk of compromising the safety of the vehicle.

[0020] Therefore, if the vehicle speed becomes equal to or lower than a predetermined speed threshold within a predetermined period of time from the notification timing of the request for a driving changeover and a driving handover operation by the driver is not detected, the vehicle control device continues deceleration control of the vehicle even after the predetermined period of time has passed. On the other hand, if the vehicle speed does not become lower than the predetermined speed threshold, the vehicle control device transfers the subject of the driving control of the vehicle to the driver when a predetermined period of time has passed from the notification timing of the request for a driving changeover, even if a driving handover operation by the driver is not detected.

[0021] FIG. 1 is a schematic diagram of a vehicle control system in which a vehicle control device is implemented. FIG. 2 is a hardware configuration diagram of an electronic control device, which is an embodiment of the vehicle control device. In this embodiment, a vehicle control system 1 that is mounted on a vehicle 10 and controls the vehicle 10 includes a GPS receiver 2, a camera 3, a storage device 4, a user interface 5, and an electronic control unit (ECU) 11, which is an example of a vehicle control device. The GPS receiver 2, the camera 3, the storage device 4, and the ECU 11 are communicatively connected via an in-vehicle network that complies with a standard such as a controller area network. Furthermore, the ECU 11 is connected to a steering device 6 including a steering wheel, a touch sensor 7 provided on the steering wheel and detecting contact of the steering wheel by the driver, an accelerator device 8 including an accelerator pedal, and a brake device 9 including a brake pedal. Furthermore, the ECU 11 is connected to a vehicle speed sensor (not shown) that measures the vehicle speed of the vehicle 10. The vehicle control system 1 may further include a distance sensor (not shown) that measures the distance from the vehicle 10 to objects present around the vehicle 10, such as a LiDAR or a radar. Furthermore, the vehicle control system 1 may have other in-vehicle devices such as a wireless communication terminal (not shown) for wirelessly communicating with other devices or a navigation device (not shown) for searching for a planned driving route to a destination.

[0022] The GPS receiver 2 receives GPS signals from GPS satellites at predetermined intervals and determines the own position of the vehicle 10 based on the received GPS signals. Then, the GPS receiver 2 outputs positioning information representing the positioning result of the own position of the vehicle 10 based on the GPS signals to the ECU 11 via the in-vehicle network at predetermined intervals. Note that the vehicle control system 1 may have a receiver conforming to another satellite positioning system instead of the GPS receiver 2.

[0023] The camera 3 is an example of an outside-vehicle sensor, and includes a two-dimensional detector configured with an array of photoelectric conversion elements, such as a CCD or C-MOS, that are sensitive to visible light, and an imaging optical system that forms an image of an area to be photographed on the two-dimensional detector. The camera 3 is attached, for example, inside the vehicle cabin of the vehicle 10 so as to face the front of the vehicle 10. The camera 3 photographs the area in front of the vehicle 10 at a predetermined photographing period (for example, 1 / 30 to 1 / 10 seconds) and generates an image of the area in front of the vehicle 10. The image obtained by the camera 3 is an example of an outside-vehicle sensor signal that represents the situation around the vehicle. The image obtained by the camera 3 may be a color image or a gray image. Note that the vehicle 10 may be provided with a plurality of cameras with different photographing directions or focal lengths. For example, a camera facing the rear of the vehicle 10 may be provided.

[0024] Every time the camera 3 generates an image, the camera 3 outputs the generated image to the ECU 11 via the in-vehicle network.

[0025] The storage device 4 is an example of a storage unit, and includes, for example, a hard disk device or a non-volatile semiconductor memory. The storage device 4 stores a high-precision map used in the automatic driving control of a vehicle. The high-precision map includes, for example, information representing road markings such as lane markings or stop lines for each road included in a predetermined area shown on the high-precision map, and information representing road signs. The high-precision map is an example of map information.

[0026] Furthermore, the storage device 4 may have a processor for executing an update process of the high-precision map, and a process related to a read request of the high-precision map from the ECU 11. The storage device 4 may transmit a request to acquire a high-precision map together with the current position of the vehicle 10 to a map server via a wireless communication terminal (not shown), for example, every time the vehicle 10 moves a predetermined distance. The storage device 4 may also receive a high-precision map of a predetermined area around the current position of the vehicle 10 from the map server via the wireless communication terminal. When the storage device 4 receives a read request of the high-precision map from the ECU 11, the storage device 4 extracts an area that includes the current position of the vehicle 10 and is relatively narrower than the above-mentioned predetermined area from the stored high-precision map, and outputs the area to the ECU 11 via the in-vehicle network.

[0027] The user interface 5 is an example of a notification device or notification unit, and has, for example, a display device such as a liquid crystal display or a touch panel display. The user interface 5 is installed in the vehicle interior of the vehicle 10, for example, near the instrument panel, facing the driver. The user interface 5 notifies the driver of the predetermined information or notification, such as a request for a driver change, received from the ECU 11 via the in-vehicle network by displaying the information or notification as an icon or as text information. The user interface 5 may have one or more light sources provided on the instrument panel, a speaker provided in the vehicle interior, or a vibration device provided on the steering wheel or the driver's seat. In this case, the user interface 5 notifies the driver of the predetermined information or notification by outputting the information or notification received from the ECU 11 via the in-vehicle network as an audio signal. Alternatively, the user interface 5 may vibrate the vibration device in response to a signal received from the ECU 11 via the in-vehicle network, thereby notifying the driver of the predetermined information or notification. Alternatively, the user interface 5 may notify predetermined information or notification by turning on or blinking a light source in response to a signal received from the ECU 11 via the in-vehicle network.

[0028] When an autonomous driving mode is applied to the vehicle 10 by an operation instruction from the driver via the user interface 5, the ECU 11 performs autonomous driving control of the vehicle 10. When the vehicle 10 is autonomously controlled, the ECU 11 determines whether the autonomous driving control of the vehicle 10 can be continued, and when it determines that the autonomous driving control cannot be continued, executes a process for transferring the control of the vehicle 10 from the ECU 11 to the driver. Furthermore, when the control of the vehicle 10 is transferred to the driver, that is, when a manual driving mode is applied to the vehicle 10, the ECU 11 may execute a function for assisting the driver in driving the vehicle 10, such as lane keep assist or collision avoidance assist.

[0029] 2, the ECU 11 has a communication interface 21, a memory 22, and a processor 23. The communication interface 21, the memory 22, and the processor 23 may each be configured as a separate circuit, or may be integrated into a single integrated circuit.

[0030] The communication interface 21 has an interface circuit for connecting the ECU 11 to the in-vehicle network. The communication interface 21 passes the positioning information to the processor 23 every time it receives positioning information from the GPS receiver 2. The communication interface 21 passes the received image to the processor 23 every time it receives an image from the camera 3. The communication interface 21 also passes the high-precision map read from the storage device 4 to the processor 23. The communication interface 21 also outputs a signal representing predetermined information or notification received from the processor 23 to the user interface 5 via the in-vehicle network.

[0031] Furthermore, the communication interface 21 is connected to the steering device 6, the touch sensor 7, the accelerator device 8, and the brake device 9. When the communication interface 21 receives a steering torque detection signal indicating the torque applied to the steering wheel from the steering device 6, the communication interface 21 passes the steering torque detection signal to the processor 23. When the communication interface 21 receives a detection signal indicating that the driver has held the steering wheel from the touch sensor 7, the communication interface 21 passes the detection signal to the processor 23. When the communication interface 21 receives an accelerator operation signal indicating the amount of depression of the accelerator pedal from the accelerator device 8, the communication interface 21 passes the accelerator operation signal to the processor 23. When the communication interface 21 receives a brake operation signal indicating the amount of depression of the brake pedal from the brake device 9, the communication interface 21 passes the brake operation signal to the processor 23.

[0032] The memory 22 is another example of a storage unit, and includes, for example, a volatile semiconductor memory and a non-volatile semiconductor memory. The memory 22 stores various algorithms and various data used in the vehicle control process executed by the processor 23 of the ECU 11. For example, the memory 22 stores a speed threshold and a message for notifying the driver in response to a driving change request. The memory 22 also stores parameters such as the mounting position, shooting direction, and focal length of the camera 3. The memory 22 also stores various parameters for identifying a classifier for object detection, a high-precision map read from the storage device 4, and a planned driving route generated by the navigation device. The memory 22 also temporarily stores information received by the ECU 11 during the vehicle control process and various data generated during the vehicle control process. The information received by the ECU 11 during the vehicle control process includes an image of the surroundings of the vehicle 10, positioning information, a steering hold detection signal, a steering torque detection signal, an accelerator operation signal, and a brake operation signal.

[0033] 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 arithmetic unit, a numerical arithmetic unit, or a graphic processing unit. The processor 23 executes vehicle control processing for the vehicle 10.

[0034] 3 is a functional block diagram of the processor 23 related to the vehicle control process. The processor 23 has a determination unit 31, a notification processing unit 32, and a control unit 33. Each of these units in the processor 23 is, for example, a functional module realized by a computer program running on the processor 23. Alternatively, each of these units in the processor 23 may be a dedicated arithmetic circuit provided in the processor 23.

[0035] The determination unit 31 determines whether or not to transfer the subject of the driving control of the vehicle 10 to the driver while the vehicle 10 is under automatic driving control. For example, the determination unit 31 determines that the subject of the control of the vehicle 10 is to be transferred to the driver when the automatic driving of the vehicle 10 cannot be continued while the vehicle 10 travels a predetermined distance from the current position of the vehicle 10 indicated by the latest positioning information. Specifically, if the vehicle 10 leaves the range represented by the high-precision map before the vehicle 10 travels a predetermined distance from the current position along the planned driving route or along the road on which the vehicle 10 is currently traveling, the vehicle 10 cannot continue automatic driving. Therefore, the determination unit 31 determines that the subject of the control of the vehicle 10 is to be transferred to the driver. For example, it is assumed that information on expressways is represented on the high-precision map, but information on general roads is not represented. In this case, for example, an interchange on the expressway is a point that leaves the high-precision map.

[0036] The determination unit 31 may also determine whether or not the autonomous driving of the vehicle 10 can be continued depending on the situation around the vehicle 10. If the determination unit 31 determines that the autonomous driving of the vehicle 10 cannot be continued, the determination unit 31 may determine that the control of the vehicle 10 is to be transferred to the driver. For example, when another vehicle cuts in front of the vehicle 10 in the lane in which the vehicle 10 is traveling, the determination unit 31 may determine that the autonomous driving of the vehicle 10 cannot be continued and that the control of the vehicle 10 is to be transferred to the driver. In addition, the traffic information received via a wireless communication terminal (not shown) may notify that road construction, lane restrictions, or congestion has occurred within a section of a predetermined distance from the current position of the vehicle 10 along the road on which the vehicle 10 is currently traveling or along the planned traveling route. In such a case, the determination unit 31 may determine that the control of the vehicle 10 is to be transferred to the driver. Alternatively, if the ECU 11 receives a signal from the camera 3 or a distance sensor (not shown) indicating a malfunction, the ECU 11 determines that it cannot continue automatic driving control of the vehicle 10, and the judgment unit 31 determines that control of the vehicle 10 should be transferred to the driver.

[0037] When the control subject is transferred due to another vehicle cutting into the own lane, the determination unit 31 detects an area in which the other vehicle is represented and an area in which the lane markings are represented on the image by inputting an image representing the surroundings of the vehicle 10, generated by the camera 3, into a classifier. The determination unit 31 can use, as such a classifier, a deep neural network (DNN) having a convolutional neural network (CNN) type architecture, such as Single Shot MultiBox Detector (SSD) or Faster R-CNN. Alternatively, the determination unit 31 may use, as such a classifier, a DNN having a self-attention network (SAN) type architecture, such as Vision transformer. Alternatively, the determination unit 31 may use, as such a classifier, a DNN for semantic segmentation, such as a Fully Convolutional Network or U-Net, which identifies the type of object represented at each pixel. Furthermore, the determination unit 31 may use a classifier based on another machine learning method, such as an AdaBoost classifier. Such a classifier is trained in advance using a large number of training images depicting vehicles or lane markings, in accordance with a predetermined learning method such as backpropagation, to detect other vehicles and lane markings from images.

[0038] The determination unit 31 determines the lane markings closest to the center line of the image on the left and right sides of the center line in the horizontal direction as the lane markings that define the own lane. The determination unit 31 then determines the area between the lane markings that define the own lane on the left and right sides of the image as the area corresponding to the own lane. Furthermore, the determination unit 31 determines the other vehicle located in the area corresponding to the own lane among the one or more detected other vehicles as a preceding vehicle that precedes the vehicle 10 in the own lane. The determination unit 31 executes the above-mentioned process on each of the series of images obtained in time series from the camera 3, thereby detecting other vehicles and lane markings from each image, and identifies the preceding vehicle traveling in the own lane based on the detection result. Furthermore, the determination unit 31 applies a tracking method such as KLT tracker to the area in which the preceding vehicle is represented in the latest image and the area in which the other vehicle is represented in the past image, thereby tracking the preceding vehicle backwards. Then, if, as a result of tracking, the preceding vehicle detected in the latest image is located in a lane different from the vehicle's lane within the immediately preceding specified period, the judgment unit 31 may determine that the preceding vehicle has cut in front of the vehicle 10.

[0039] When the determination unit 31 obtains a determination result that the control of the vehicle 10 should be transferred to the driver, the determination unit 31 notifies the notification processing unit 32 and the control unit 33 of the determination result. Furthermore, the determination unit 31 notifies the control unit 33 of a signal indicating the event that caused the determination to transfer the control of the vehicle 10 to the driver.

[0040] When the notification processing unit 32 is notified by the determination unit 31 that the control subject of the vehicle 10 is to be transferred to the driver, the notification processing unit 32 notifies the driver of a request for a driving changeover via the user interface 5. At that time, the notification processing unit 32 displays a message or an icon representing the request for a driving changeover on a display device of the user interface 5, or lights or blinks a light source corresponding to the request. Alternatively, the notification processing unit 32 outputs an audio signal representing the request to a speaker of the user interface 5. Alternatively, the notification processing unit 32 vibrates a vibration device of the user interface 5 according to a vibration method (vibration period or vibration intensity) corresponding to the request. Note that, when the user interface 5 has two or more of the above devices, the notification processing unit 32 may notify the driver of a request for a driving changeover via each or any of the two or more devices.

[0041] The notification processing unit 32 notifies the control unit 33 of the notification timing when the request for a driving change is notified to the driver via the user interface 5.

[0042] The control unit 33 performs automatic driving control of the vehicle 10 while the automatic driving mode is applied to the vehicle 10. The control unit 33 continues the automatic driving control until a predetermined timing after the notification timing at which the request for driving change is notified or until a driving handover operation by the driver is detected. When the predetermined timing is reached, the control unit 33 starts executing deceleration control to decelerate the vehicle 10 at a predetermined deceleration as one aspect of the automatic driving control. The control unit 33 also measures the elapsed time from the notification timing. When the speed of the vehicle 10 becomes equal to or less than a predetermined speed threshold and a driving handover operation by the driver is not detected, the control unit 33 continues the deceleration control of the vehicle 10 even after a predetermined period has elapsed. On the other hand, when the speed of the vehicle 10 does not fall below the predetermined speed threshold and a driving handover operation by the driver is not detected until a predetermined period has elapsed from the notification timing, the control unit 33 transfers the control subject of the vehicle 10 to the driver regardless of whether or not the deceleration control is performed.

[0043] The control unit 33 may determine whether the speed of the vehicle 10 has fallen below the speed threshold by comparing the measured value of the speed of the vehicle 10, received by the ECU 11 from a vehicle speed sensor (not shown), with the speed threshold.

[0044] The predetermined timing for starting the execution of the deceleration control is, for example, the timing when the speed of the vehicle 10 becomes equal to or lower than the predetermined speed threshold after the notification timing. Alternatively, the predetermined timing may be the notification timing itself when the request for a driving change is notified. Alternatively, the predetermined timing may be the timing when a predetermined waiting period has elapsed from the notification timing. However, the predetermined waiting period is set to a period shorter than the above-mentioned predetermined period, for example, 1 to 2 seconds. Also, the predetermined period can be set to, for example, 3 to 5 seconds. Furthermore, the predetermined speed threshold is set to, for example, the upper limit of the speed at which the vehicle 10 may accelerate due to the creep phenomenon, for example, 10 km / h to 20 km / h.

[0045] The control unit 33 controls each part of the vehicle 10 so that the vehicle 10 travels at a predetermined speed while the vehicle 10 is under automatic driving control. The predetermined speed may be a speed set by the driver via the user interface 5, or a speed limit of the road on which the vehicle 10 is traveling, which is specified by referring to the current position of the vehicle 10 shown in the high-precision map and the latest positioning information. In addition, when there is a preceding vehicle traveling in the own lane, the control unit 33 may control the speed of the vehicle 10 so that the distance between the preceding vehicle and the vehicle 10 is kept constant. The distance between the preceding vehicle and the vehicle 10 is estimated based on the area in which the vehicle 10 is represented on the image generated by the camera 3. That is, it is estimated that the position of the bottom end of the area in which the vehicle 10 is represented on the image represents the position where the preceding vehicle and the road surface are in contact. The position of the bottom end of the area on the image represents the direction to the position where the preceding vehicle and the road surface are in contact as seen from the camera 3. Therefore, the control unit 33 can estimate the distance between the vehicle 10 and the preceding vehicle based on the direction from the camera 3 that corresponds to the position of the bottom edge of the area in which the vehicle 10 is depicted on the image and the installation height of the camera 3. Furthermore, if the vehicle 10 is equipped with a distance sensor such as a LiDAR sensor, the control unit 33 may determine the distance to an object present in the forward direction of the vehicle 10, measured by the distance sensor, as the distance between the vehicle 10 and the preceding vehicle.

[0046] The control unit 33 sets the accelerator opening or the braking amount so that the speed of the vehicle 10 becomes the speed determined as described above. The control unit 33 then calculates the fuel injection amount according to the set accelerator opening, and outputs a control signal corresponding to the fuel injection amount to a fuel injection device of the engine of the vehicle 10. Alternatively, the control unit 33 calculates the amount of power supplied to the motor according to the set accelerator opening, and controls a drive circuit of the motor so that the amount of power is supplied to the motor. Furthermore, the control unit 33 outputs a control signal corresponding to the set braking amount to the brake device 9.

[0047] In addition, when the deceleration control is started, the control unit 33 controls the deceleration of the vehicle 10 to be a predetermined deceleration (for example, 0.7 m / s) while the deceleration control is being executed. 2The control unit 33 then determines the fuel injection amount according to the set accelerator opening, and outputs a control signal corresponding to the fuel injection amount to a fuel injection device of the engine of the vehicle 10. Alternatively, the control unit 33 determines the amount of power to be supplied to the motor according to the set accelerator opening, and controls a drive circuit of the motor so that the amount of power is supplied to the motor. Furthermore, the control unit 33 outputs a control signal corresponding to the set braking amount to the brake device 9.

[0048] Furthermore, when the speed of the vehicle 10 becomes 0 while the deceleration control is continuing, the control unit 33 may set the accelerator opening to 0 or increase the braking amount above a predetermined value so that the vehicle 10 continues to be stopped.

[0049] The control unit 33 detects the driver's operation to take over the driving based on at least one of the driver's steering operation, steering hold, accelerator operation, and brake operation. When the control unit 33 detects the driver's operation to take over the driving, the control unit 33 transfers the main control of the driving of the vehicle 10 to the driver. After that, the driving of the vehicle 10 is controlled according to the driving operation of the driver.

[0050] For example, until a predetermined period of time has elapsed since the notification timing, the control unit 33 determines that the driver has performed an operation to take over driving in accordance with any one of the following (a) to (c). (a) When the torque applied to the steering wheel, which is represented by the steering torque detection signal received from the steering device 6, exceeds a predetermined torque value. In other words, when it is detected that the driver has operated the steering wheel. (b) When the ECU 11 receives from the touch sensor 7 a detection signal indicating that the driver has held the steering wheel, and when the accelerator depression amount indicated by the accelerator operation signal received from the accelerator device 8 is equal to or greater than a predetermined amount, that is, when it is detected that the driver has held the steering wheel and operated the accelerator device 8. (c) When the ECU 11 receives from the touch sensor 7 a detection signal indicating that the driver has held the steering wheel, and when the brake pedal depression amount indicated by the brake operation signal received from the brake device 9 is equal to or greater than a predetermined amount, that is, when it is detected that the driver has held the steering wheel and operated the brake device 9.

[0051] Furthermore, after a predetermined period of time has elapsed from the notification timing, the control unit 33 may determine that the driver has performed a driving handover operation if the driver operates the accelerator device 8 or the brake device 9 even if the driver is not holding the steering wheel. That is, in the above determination conditions (b) and (c), the fact that the ECU 11 has received a detection signal from the touch sensor 7 indicating that the driver has held the steering wheel may be omitted. In this way, by relaxing the requirement for taking over driving after a predetermined period of time has elapsed from the notification timing, the control unit 33 can improve the convenience of the driver while preventing the vehicle 10 from unintentionally accelerating after control is transferred to the driver.

[0052] Furthermore, after the vehicle 10 has stopped, the control unit 33 may determine that the driver has performed a driving handover operation when it is detected that the driver has operated the accelerator or brake, or that the shift lever has been placed in the parking position. Alternatively, after the vehicle 10 has stopped, the control unit 33 may determine that the driver has performed a driving handover operation when the electric parking brake is turned on.

[0053] FIG. 4(a) is a schematic diagram showing the duration of the autonomous driving control in the case where the speed of the vehicle 10 does not fall below a predetermined speed threshold during a predetermined period from the notification timing. FIG. 4(b) is a schematic diagram showing the duration of the autonomous driving control including the deceleration control in the case where the speed of the vehicle 10 falls below a predetermined speed threshold during a predetermined period from the notification timing. In FIG. 4(a) and FIG. 4(b), the horizontal axis represents the elapsed time, and the vertical axis represents the speed of the vehicle 10. In FIG. 4(a), a graph 401 represents the change in the speed of the vehicle 10 over time. Similarly, in FIG. 4(b), a graph 402 represents the change in the speed of the vehicle 10 over time.

[0054] As shown in FIG. 4(a), the speed of the vehicle 10 is kept constant until time t1. Then, at time t1, a request for a driver handover is notified to the driver. That is, time t1 is the notification timing. Even after the notification timing t1, the automatic driving control of the vehicle 10 continues, and although the speed of the vehicle 10 varies over time in relation to the preceding vehicle, for example, the speed of the vehicle 10 is higher than the speed threshold Thv during the period from the notification timing t1 to ...2 to the notification timing t2, the speed of the vehicle 10 is based on the driving operation by the driver. In this example, since the speed of the vehicle 10 does not decrease much when the control is transferred to the driver, if the driver does not perform a driving operation, the speed of the vehicle 10 is decelerated by engine braking even after the time t2.

[0055] On the other hand, in the example shown in FIG. 4(b), the speed of the vehicle 10 is kept constant until time t1. Then, at time t1, a request for a driver handover is notified to the driver. In this example, at time t2 after the notification timing t1, the speed of the vehicle 10 falls below the speed threshold Thv, and deceleration control is executed from time t2 onwards. Then, the speed of the vehicle 10 decreases over time. In this case, unless a driving handover operation by the driver is detected, deceleration control continues even after time t3 when a predetermined period P has elapsed from the notification timing t1. Then, when the speed of the vehicle 10 becomes 0, the vehicle 10 is maintained stopped thereafter.

[0056] 5 is an operational flowchart of the vehicle control process executed by the processor 23. The processor 23 may execute the vehicle control process in accordance with the following operational flowchart.

[0057] The determination unit 31 of the processor 23 determines whether or not to transfer the subject of driving control of the vehicle 10 to the driver (step S101). If it is determined that the subject of driving control of the vehicle 10 is to be transferred to the driver, the notification processing unit 32 of the processor 23 notifies the driver of a request for a driving changeover via the user interface 5 (step S102).

[0058] After the driver is notified of the request for driving changeover, the control unit 33 of the processor 23 determines whether or not the driver's operation to take over driving is detected (step S103). If the driver's operation to take over driving is detected (step S103-Yes), the control unit 33 stops the automatic driving control of the vehicle 10 (step S104). After that, the vehicle 10 is controlled according to the driving operation by the driver, and the ECU 11 ends the vehicle control process.

[0059] On the other hand, if the driver's operation to take over driving is not detected (step S103-No), the control unit 33 determines whether the speed of the vehicle 10 is higher than a predetermined speed threshold Thv (step S105). If the speed of the vehicle 10 is higher than the predetermined speed threshold Thv (step S105-Yes), the control unit 33 determines whether a predetermined period has passed since the notification timing (step S106). If the predetermined period has passed since the notification timing (step S106-Yes), the control unit 33 stops the automatic driving control of the vehicle 10 (step S104). Thereafter, the vehicle 10 is controlled according to the driving operation by the driver, and the ECU 11 ends the vehicle control process.

[0060] On the other hand, if the predetermined period has not elapsed since the notification timing (step S106-No), the control unit 33 continues the automatic driving control of the vehicle 10 with the driver being notified of the request for a driving changeover (step S107). Then, the control unit 33 repeats the processes from step S103 onward.

[0061] In addition, in step S105, if the speed of the vehicle 10 is equal to or lower than the predetermined speed threshold Thv (step S105-No), the control unit 33 continues the deceleration control of the vehicle 10 while the driver is notified of the request for a driving changeover (step S108). Then, the control unit 33 repeats the processes in and after step S103.

[0062] As described above, when the vehicle control device determines that the automatic driving control of the vehicle cannot be continued for a predetermined reason, it notifies the driver of a request for a driver changeover. If the vehicle maintains a speed equal to or higher than a predetermined speed threshold until a predetermined period of time has elapsed from the timing of the notification of the driver changeover request, the vehicle control device transfers the subject of driving control to the driver at the time of the lapse of the predetermined period of time even if the vehicle control device does not detect the driver's operation to take over driving. This allows the vehicle control device to reliably transfer the subject of control of the vehicle to the driver when it is not expected that the vehicle will accelerate unintentionally after the control subject is transferred to the driver. On the other hand, at a predetermined timing after the timing of the notification of the driver changeover request, the vehicle control device executes deceleration control. If the speed of the vehicle becomes equal to or lower than a predetermined speed threshold before the predetermined period of time has elapsed from the notification timing and the driver's operation to take over driving is not detected, the vehicle control device continues the deceleration control of the vehicle even after the predetermined period of time has elapsed. Therefore, this vehicle control device can prevent unintended acceleration of the vehicle due to creep, thereby improving safety when the main control of the vehicle's driving is handed over from the vehicle control device to the driver.

[0063] According to a modified example, the control unit 33 may switch the judgment condition for judging that the driver has performed the operation of taking over the driving, depending on the speed of the vehicle. For example, when the speed of the vehicle 10 is equal to or lower than a predetermined speed threshold, the control unit 33 may judge that the driver has performed the operation of taking over the driving only when the driver has performed either the accelerator operation or the brake operation. That is, when the speed of the vehicle 10 is equal to or lower than a predetermined speed threshold, the control unit 33 judges that the driver has performed the operation of taking over the driving only when the judgment condition (b) or (c) above is satisfied. Note that, even in this modified example, after a predetermined period has elapsed from the notification timing, the judgment conditions (b) and (c) above may omit that the ECU 11 has received a detection signal from the touch sensor 7 indicating that the driver has held the steering wheel. Therefore, when the speed of the vehicle 10 is equal to or lower than a predetermined speed threshold, the control unit 33 continues the deceleration control unless the accelerator operation or the brake operation by the driver is detected.

[0064] On the other hand, when the speed of the vehicle 10 is higher than a predetermined speed threshold, the control unit 33 may determine that the driver has performed a driving handover operation when any of the above judgment conditions (a) to (c) is satisfied, that is, when a predetermined operation including holding the steering wheel is performed. Alternatively, when the speed of the vehicle 10 is higher than a predetermined speed threshold, the control unit 33 may determine that the driver has performed a driving handover operation simply by detecting that the driver has operated or held the steering wheel. That is, in the above judgment condition (b), the detection of the operation of the accelerator device 8 by the driver may be omitted. Also, in the above judgment condition (c), the detection of the operation of the brake device 9 by the driver may be omitted.

[0065] 6 is an operation flowchart of the vehicle control process according to this modification. The determination unit 31 of the processor 23 determines whether or not to transfer the subject of the driving control of the vehicle 10 to the driver (step S201). If it is determined that the subject of the driving control of the vehicle 10 is to be transferred to the driver, the notification processing unit 32 of the processor 23 notifies the driver of a request for a driving changeover via the user interface 5 (step S202). Then, the control unit 33 of the processor 23 determines whether or not the speed of the vehicle 10 is higher than a predetermined speed threshold Thv (step S203).

[0066] If the speed of the vehicle 10 is higher than the predetermined speed threshold Thv (step S203-Yes), the control unit 33 determines whether or not any of the above judgment conditions (a) to (c) is satisfied (step S204). If any of the above judgment conditions (a) to (c) is satisfied, that is, if the driver's operation to take over driving is detected (step S204-Yes), the control unit 33 stops the automatic driving control of the vehicle 10 (step S205). Thereafter, the vehicle 10 is controlled according to the driving operation by the driver, and the ECU 11 ends the vehicle control process.

[0067] On the other hand, if none of the above judgment conditions (a) to (c) is satisfied, that is, if the driver's operation to take over the driving is not detected (step S204-No), the control unit 33 continues the automatic driving control of the vehicle 10 (step S206). In this case, the state in which the driver is notified of the request to take over the driving is maintained. Then, the control unit 33 repeats the processes from step S203 onwards.

[0068] On the other hand, in step S203, if the speed of the vehicle 10 is equal to or lower than the predetermined speed threshold Thv (step S203-No), the control unit 33 starts deceleration control (step S207). Then, the control unit 33 determines whether or not any of the above-mentioned judgment conditions (b) and (c) is satisfied (step S208). As described above, in the judgment conditions (b) and (c), the detection of the driver holding the steering wheel may be omitted. If any of the judgment conditions (b) and (c) is satisfied, that is, if the driver's takeover operation, including the accelerator operation or the brake operation, is detected (step S208-Yes), the control unit 33 stops the automatic driving control (step S205). After that, the vehicle 10 is controlled according to the driving operation by the driver, and the ECU 11 ends the vehicle control process.

[0069] On the other hand, if neither of the above judgment conditions (b) nor (c) is satisfied, that is, if neither the accelerator operation nor the brake operation is detected (step S208-No), the control unit 33 continues the deceleration control of the vehicle 10 (step S209). In this case, the state in which the driver is notified of the request for a driving changeover is maintained. Then, the control unit 33 repeats the processes from step S203 onward.

[0070] In this modified example, when deceleration control is not applied, the control unit 33 may transfer the driving control to the driver if the driver's operation to take over driving is not detected even after a predetermined period of time has elapsed from the notification timing.

[0071] According to this modification, when the vehicle speed is low, the vehicle control device requires the driver to operate the accelerator or brake as a prerequisite for taking over the driving operation, thereby preventing the vehicle from accelerating unintentionally when the driver takes over the driving operation. Furthermore, when the vehicle speed is high, the vehicle control device enables the driver to take over the driving operation by operating something other than the accelerator and brake, thereby preventing the driver's convenience from being impaired.

[0072] In the above embodiment or modified example, the control unit 33 may dynamically set the speed threshold according to the environment around the vehicle 10. For example, the control unit 33 may adjust the speed threshold according to the gradient of the road on which the vehicle 10 is traveling. In this case, the control unit 33 may set the speed threshold when the vehicle 10 is traveling on an uphill road lower than the speed threshold when the vehicle 10 is traveling on a flat road. This is because, when the vehicle 10 is traveling on an uphill road, the possibility of the vehicle 10 accelerating after the automatic driving control is stopped is reduced. Conversely, the control unit 33 may set the speed threshold when the vehicle 10 is traveling on a downhill road higher than the speed threshold when the vehicle 10 is traveling on a flat road. This is because, when the vehicle 10 is traveling on a downhill road, the possibility of the vehicle 10 accelerating after the automatic driving control is stopped is increased. The control unit 33 may obtain the gradient of the road on which the vehicle 10 is traveling by referring to the current position of the vehicle 10 indicated by the latest positioning information and the high-precision map. According to this modification, the control unit 33 can adjust the speed threshold to an appropriate value.

[0073] In the above embodiment or modified example, the control unit 33 may determine whether or not there is a risk of the vehicle 10 colliding with another object due to acceleration of the vehicle 10 after the subject of driving control is transferred to the driver. In this case, the control unit 33 may determine whether or not there is a risk depending on the situation around the vehicle 10 or the cause of the determination to transfer the subject of control of the vehicle 10 to the driver. Then, if there is a risk of the vehicle 10 colliding with another object due to the acceleration of the vehicle 10, the control unit 33 executes the same processing as in the above embodiment. That is, the control unit 33 continues the deceleration control as long as the speed of the vehicle 10 becomes equal to or lower than a predetermined speed threshold and a predetermined period has elapsed since the timing of the notification of the request for driving change is notified, and the control unit 33 does not detect the driver's operation to take over the driving. For example, if the cause of the determination to transfer the subject of control to the driver is the occurrence of an intrusion of another vehicle in front of the vehicle 10, the control unit 33 may execute the same processing as in the above embodiment, assuming that there is a risk of the vehicle 10 colliding with another object due to the acceleration of the vehicle 10. Furthermore, by referring to the position of the vehicle 10 represented by the positioning information and the high-precision map at the timing of notification of the request for a driving change, the control unit 33 may determine whether the vehicle 10 is traveling on a curve at the timing of notification. If the vehicle 10 is traveling on a curve at the timing of notification, the control unit 33 may execute the same process as in the above embodiment.

[0074] On the other hand, there are cases where it is assumed that there will be no immediate danger of the vehicle 10 colliding with another object after the control subject is transferred to the driver, such as when the driving change request is caused by the vehicle 10 exiting an area covered by a high-precision map. In such cases, the control unit 33 may stop the automatic driving control or deceleration control of the vehicle 10 and transfer the control subject to the driver when a predetermined period has elapsed from the notification timing, regardless of the speed of the vehicle 10. In addition, the control unit 33 may not perform deceleration control itself if the automatic driving control requests the vehicle 10 to accelerate at the notification timing when the driver is notified of the request for driving change.

[0075] Furthermore, the control unit 33 may determine whether or not there is a risk of the vehicle 10 colliding with the preceding vehicle when the driver does not perform driving operation even if the control subject is transferred after a predetermined period from the notification timing based on the distance, relative speed, and relative acceleration between the vehicle 10 and the preceding vehicle. If there is such a risk, the control unit 33 may continue the deceleration control as in the above embodiment when the speed of the vehicle 10 becomes equal to or lower than a predetermined speed threshold and the driver's operation to take over driving is not detected even after a predetermined period from the notification timing. Conversely, if there is no such risk, the control unit 33 may transfer the control subject to the driver when a predetermined period from the notification timing has elapsed regardless of the speed of the vehicle 10. Note that the control unit 33 may execute the same process as the determination unit 31 to detect the preceding vehicle from each of the series of time-series images generated by the camera 3, and track the detected preceding vehicle to obtain the change over time in the inter-vehicle distance between the vehicle 10 and the preceding vehicle. Then, the control unit 33 applies a prediction filter such as a Kalman filter to the time-dependent change in the inter-vehicle distance to predict time-series changes in the inter-vehicle distance, relative speed, and relative acceleration after a predetermined period has elapsed from the notification timing. Based on the prediction result, when it is predicted that the vehicle 10 and the preceding vehicle will approach within a predetermined danger distance, the control unit 33 may determine that there is a risk of the vehicle 10 colliding with the preceding vehicle.

[0076] Alternatively, by continuing the deceleration control even after a predetermined period has elapsed from the notification timing as in the above embodiment, there may be a risk of collision between the vehicle 10 and a following vehicle traveling behind the vehicle 10 in the own lane. In such a case, the control unit 33 may not perform the deceleration control regardless of the speed of the vehicle 10. Then, the control unit 33 may transfer the control subject to the driver at a time point when a predetermined period has elapsed from the notification timing. In this case, the control unit 33 detects the following vehicle by performing the same process as the determination unit 31 from each of a series of time-series images generated by the camera 3 provided to capture the rear of the vehicle 10. Then, the control unit 33 may obtain the change over time in the inter-vehicle distance between the vehicle 10 and the following vehicle by tracking the detected following vehicle. The control unit 33 applies a prediction filter such as a Kalman Filter to the change over time in the inter-vehicle distance, the relative speed, and the relative acceleration to predict the change over time in the inter-vehicle distance, the relative speed, and the relative acceleration after a predetermined period has elapsed from the notification timing. If it is predicted based on the prediction result that the vehicle 10 and the following vehicle will approach within a predetermined danger distance, the control unit 33 may determine that there is a risk of the vehicle 10 colliding with the following vehicle.

[0077] Alternatively, the control unit 33 may switch the control depending on the deceleration obtained when the vehicle 10 coasts after a predetermined period has elapsed from the notification timing. In this case, the control unit 33 may refer to a reference table that indicates the relationship between the speed and deceleration of the vehicle 10, and obtain the deceleration corresponding to the speed of the vehicle 10 at the notification timing. Note that such a reference table may be stored in the memory 22 in advance. In addition, when the vehicle 10 is driven by a motor, the reference table may indicate not only the vehicle speed of the vehicle 10, but also the relationship between the remaining battery charge of the vehicle 10 and the deceleration. Then, the control unit 33 may refer to the reference table to obtain the deceleration corresponding to the speed of the vehicle 10 and the remaining battery charge at the notification timing. When the deceleration is less than the predetermined deceleration threshold, the control unit 33 may continue the deceleration control when the speed of the vehicle 10 becomes equal to or less than the predetermined speed threshold and the driver's operation to take over driving is not detected even after a predetermined period has elapsed from the notification timing, as in the above embodiment. Conversely, when the deceleration is equal to or greater than the predetermined deceleration threshold, the control unit 33 may not perform deceleration control regardless of the speed of the vehicle 10.

[0078] Thus, according to this modification, the control unit 33 switches whether to continue deceleration control when the driver's operation to take over driving is not detected, depending on the reason for determining that driving control of the vehicle 10 should be transferred to the driver or the circumstances around the vehicle 10. This allows the control unit 33 to more appropriately time the handover of driving control to the driver while ensuring the safety of the vehicle 10.

[0079] Furthermore, as in the above-mentioned modified example, when the automatic driving control is continued even after a predetermined period from the notification timing, the control unit 33 may strengthen the notification of the request for a driver change to the driver when the predetermined period from the notification timing has passed. In this case, the control unit 33 strengthens the notification of the request for a driver change by, for example, increasing the brightness of the message or icon of the request for a driver change displayed on the user interface 5 and changing the color of the message or icon to a more conspicuous color. Alternatively, the control unit 33 may strengthen the notification of the request for a driver change by increasing the volume of the voice of the request for a driver change emitted from the speaker of the user interface 5 or by increasing the vibration of the vibration device of the user interface 5. Furthermore, if the driver's operation to take over the driver is not detected even after a certain period has elapsed after strengthening the notification of the request for a driver change, the control unit 33 may activate the driver's abnormality response system. That is, the control unit 33 may activate the abnormality response system by sounding the horn, turning on the hazard lights, or connecting to the help network via a wireless communication terminal to notify of an emergency.

[0080] As described above, those skilled in the art can make various modifications to the embodiments within the scope of the present invention. [Explanation of symbols]

[0081] 1 Vehicle Control System 10 Vehicles 2 GPS receiver 3. Camera 4. Storage Devices 5 User Interface 6 Steering Gear 7 Touch Sensor 8 Accelerator 9 Brake system 11 Electronic Control Unit (ECU) 21 Communication Interface 22 Memory 23 Processors 31 Judgment section 32 Notification processing section 33 Control Unit

Claims

1. A determination unit that determines to transfer the subject of driving control of the vehicle to a driver when the automatic driving control of the vehicle cannot be continued during the automatic driving control; A notification processing unit that notifies the driver of a request for driving changeover via a notification device provided in the vehicle when the subject of driving control of the vehicle is transferred to the driver; decelerating the vehicle at a predetermined timing after the notification timing of the request for driver change; If the speed of the vehicle becomes equal to or less than a predetermined speed threshold value before a predetermined period of time has elapsed from the notification timing and a driving handover operation by the driver is not detected, the deceleration control of the vehicle is continued even after the predetermined period of time has elapsed; a control unit that, when the speed of the vehicle does not fall below the predetermined speed threshold until the predetermined period has elapsed from the notification timing and a driving handover operation by the driver is not detected, stops automatic driving control of the vehicle when the predetermined period has elapsed and executes control of the vehicle to respond to an abnormality of the driver after the predetermined period has elapsed; having the predetermined speed threshold value is a value corresponding to an upper limit of a speed at which the vehicle may accelerate due to a creep phenomenon, The control unit determines whether or not there is a risk of the vehicle colliding with another object due to acceleration of the vehicle after the control of the vehicle is transferred to the driver, depending on the cause of the determination to transfer the control of the vehicle to the driver or the situation around the vehicle, and continues deceleration control of the vehicle even after the predetermined period has elapsed only when it is determined that there is a risk. Vehicle control device.

2. The control unit determines that the takeover operation has been performed when a steering operation of the vehicle by the driver or an operation of an accelerator or a brake together with a steering operation by the driver is detected until the predetermined period has elapsed from the notification timing, On the other hand, when the predetermined period has elapsed from the notification timing, if the driver operates the steering wheel of the vehicle, or if the driver does not hold the steering wheel but an accelerator or brake operation is detected, the vehicle control device determines that the handover operation has been performed.

3. 2. The vehicle control device according to claim 1, wherein the control unit continues deceleration control of the vehicle when the speed of the vehicle is equal to or lower than a predetermined speed threshold, unless an accelerator or brake operation by the driver as the handover operation is detected, and when the speed of the vehicle is higher than the predetermined speed threshold, the control unit stops automatic driving control of the vehicle when a steering operation by the driver or a predetermined operation including steering by the driver is detected as the handover operation.

4. The vehicle control device according to claim 1 , wherein the control unit adjusts the predetermined speed threshold in accordance with a gradient of a road on which the vehicle is traveling.

5. In a vehicle undergoing automatic driving control, when the automatic driving control cannot be continued, it is determined that the subject of driving control of the vehicle is to be transferred to the driver; When transferring the subject of driving control of the vehicle to the driver, notifying the driver of a request for driving change via a notification device provided in the vehicle; decelerating the vehicle at a predetermined timing after the notification timing of the request for driver change; If the speed of the vehicle becomes equal to or less than a predetermined speed threshold value before a predetermined period of time has elapsed from the notification timing and a driving handover operation by the driver is not detected, the deceleration control of the vehicle is continued even after the predetermined period of time has elapsed; If the speed of the vehicle does not fall below the predetermined speed threshold until the predetermined period has elapsed from the notification timing, and if a driving handover operation by the driver is not detected, automatic driving control of the vehicle is stopped at the time when the predetermined period has elapsed, and control of the vehicle to respond to an abnormality of the driver is executed after the predetermined period has elapsed. Including, the predetermined speed threshold value is a value corresponding to an upper limit of a speed at which the vehicle may accelerate due to a creep phenomenon, Continuing the deceleration control of the vehicle includes determining whether or not there is a risk of the vehicle colliding with another object due to acceleration of the vehicle after the subject of the driving control of the vehicle is transferred to the driver, depending on the cause of the determination to transfer the subject of the driving control of the vehicle to the driver or the situation around the vehicle, and continuing the deceleration control of the vehicle even after the predetermined period has elapsed only when it is determined that there is such a risk. A vehicle control method.

6. In a vehicle undergoing automatic driving control, when the automatic driving control cannot be continued, it is determined that the subject of driving control of the vehicle is to be transferred to the driver; When transferring the subject of driving control of the vehicle to the driver, notifying the driver of a request for driving change via a notification device provided in the vehicle; decelerating the vehicle at a predetermined timing after the notification timing of the request for driver change; If the speed of the vehicle becomes equal to or less than a predetermined speed threshold value before a predetermined period of time has elapsed from the notification timing and a driving handover operation by the driver is not detected, the deceleration control of the vehicle is continued even after the predetermined period of time has elapsed; If the speed of the vehicle does not fall below the predetermined speed threshold until the predetermined period has elapsed from the notification timing, and if a driving handover operation by the driver is not detected, automatic driving control of the vehicle is stopped at the time when the predetermined period has elapsed, and control of the vehicle to respond to an abnormality of the driver is executed after the predetermined period has elapsed. and causing a processor mounted on the vehicle to execute the steps of: the predetermined speed threshold value is a value corresponding to an upper limit of a speed at which the vehicle may accelerate due to a creep phenomenon, Continuing the deceleration control of the vehicle includes determining whether or not there is a risk of the vehicle colliding with another object due to acceleration of the vehicle after the subject of the driving control of the vehicle is transferred to the driver, depending on the cause of the determination to transfer the subject of the driving control of the vehicle to the driver or the situation around the vehicle, and continuing the deceleration control of the vehicle even after the predetermined period has elapsed only when it is determined that there is such a risk. A computer program for controlling a vehicle.

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