Vehicle controller

Abstract

To provide a vehicle controller capable of towing a vehicle to be towed, and of appropriately setting timing to interrupt lane change control of a vehicle to which automatic operation control is applied.SOLUTION: A vehicle controller comprises: a towing detection unit 31 for detecting that a vehicle 11 to be towed is towed, when a vehicle 10 is subjected to automatic operation control; a determination unit 38 for determining whether or not to satisfy an interruption condition that is set based on at least one of change in a relative position between the vehicle 10 and the other vehicle traveling in an adjacent lane, during execution of lane change control executed when a predetermined condition is satisfied; and an interruption instruction unit 39 for interrupting the lane change control when the interruption condition is satisfied. The determination unit 38 releases the interruption condition when it is detected that the vehicle 10 tows the vehicle 11 to be towed rather than the interruption condition when it is not detected that the vehicle 10 tows the vehicle 11 to be towed.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to a vehicle control device.

Background Art

[0002] The behavior of a vehicle towing another vehicle may be different from that of a vehicle not towing. Therefore, in the automatic driving control of a vehicle towing another vehicle, it is required to control the vehicle in consideration of the difference in vehicle behavior depending on whether towing is being performed or not. Thus, a technique has been proposed in which different controls are executed for a vehicle depending on whether or not a towed vehicle is connected (see Patent Document 1).

[0003] When the driving support device disclosed in Patent Document 1 detects the connection of a towed vehicle, it sets the driving mode to a restricted second driving support mode in which the second driving support mode for performing automatic driving without the condition of holding the steering wheel is applied only during continuous driving in the same lane. And when changing lanes, this driving support device changes the driving mode to the first driving support mode for performing automatic driving on the condition of holding the steering wheel.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When automatic driving control is applied to a vehicle towing a towed vehicle, it may be required to increase the degree of the driver's involvement in driving. In such a case, it is required to be able to appropriately set the timing for increasing the degree of the driver's involvement in driving.

[0006] Accordingly, an object of the present invention is to provide a vehicle control device capable of appropriately setting a timing for interrupting a lane change control of a vehicle that is towing a towed vehicle and to which an automatic driving control is applied.

Means for Solving the Problems

[0007] According to one embodiment, a vehicle control device is provided. The vehicle control device includes a towing detection unit that detects that the vehicle is towing a towed vehicle when the vehicle is under automatic driving control, a detection unit that detects a relative position and a relative speed between the vehicle and another vehicle traveling in an adjacent lane adjacent to the own lane in which the vehicle is traveling, a control unit that executes a lane change control of the vehicle so as to change the lane of the vehicle from the own lane to the adjacent lane when a predetermined condition is satisfied, a determination unit that determines whether or not an interruption condition set based on at least one of a change in the relative position and the relative speed between the other vehicle and the vehicle is satisfied during the execution of the lane change control, and an interruption instruction unit that causes the control unit to interrupt the lane change control when the interruption condition is satisfied. The determination unit relaxes the interruption condition when it is detected that the vehicle is towing a towed vehicle compared to the interruption condition when it is not detected that the vehicle is towing a towed vehicle.

Advantages of the Invention

[0008] The vehicle control device according to the present invention has an effect that it can appropriately set a timing for interrupting a lane change control of a vehicle that is towing a towed vehicle and to which an automatic driving control is applied.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

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Figure 7

Figure 8

Figure 9

Mode for Carrying Out the Invention

[0010] Hereinafter, a vehicle control device, a vehicle control method executed on the vehicle control device, and a vehicle control computer program will be described with reference to the drawings. This vehicle control device automatically controls the running of a vehicle capable of towing a towed vehicle. More specifically, this vehicle control device determines whether or not a participation request condition for requesting a driver of the vehicle to participate in the driving is satisfied, and when it is determined that the participation request condition is satisfied, it notifies a request for participation in the driving via a notification device provided in the vehicle interior. And this vehicle control device relaxes the participation request condition when the vehicle is detected to be towing a towed vehicle compared to the participation request condition when the vehicle is not detected to be towing a towed vehicle.

[0011] FIG. 1 is a schematic configuration 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 unit which is an embodiment of the vehicle control device. In the present embodiment, a vehicle control system 1 mounted on a vehicle 10 and controlling the vehicle 10 includes a camera 2, a driver monitoring camera 3, a GPS receiver 4, a behavior sensor 5, a wireless communication terminal 6, a notification device 7, a storage device 8, and an electronic control unit (ECU) 9 which is an example of the vehicle control device. The camera 2, the driver monitoring camera 3, the GPS receiver 4, the wireless communication terminal 6, the notification device 7, the storage device 8, and the ECU 9 are communicably connected via an in-vehicle network conforming to a standard such as a controller area network. Further, the behavior sensor 5 is also communicably connected to the ECU 9. Note that the vehicle control system 1 may further include a distance measuring sensor (not shown) such as LiDAR or radar that measures the distance from the vehicle 10 to an object existing around the vehicle 10. Further, the vehicle control system 1 may further include a navigation device (not shown) for searching for a route to a destination.

[0012] Furthermore, the vehicle 10 has a device for towing a towed vehicle 11, such as a tow hook, and is capable of towing the towed vehicle 11.

[0013] The camera 2 is an example of an out-of-vehicle sensor, and includes a two-dimensional detector composed of an array of photoelectric conversion elements sensitive to visible light, such as a CCD or a C-MOS, and an imaging optical system that forms an image of an area to be photographed on the two-dimensional detector. The camera 2 is attached, for example, inside the vehicle cabin of the vehicle 10 so as to face the front of the vehicle 10. The camera 2 photographs the front area of the vehicle 10 at a predetermined photographing cycle (for example, 1 / 30 second to 1 / 10 second), and generates an image in which the front area is shown. The image obtained by the camera 2 is an example of an out-of-vehicle sensor signal representing the situation around the vehicle 10. Note that a plurality of cameras having different photographing directions or focal lengths may be provided on the vehicle 10.

[0014] Each time the camera 2 generates an image, it outputs the generated image to the ECU 9 via the in-vehicle network.

[0015] The driver monitoring camera 3 is an example of an in-vehicle sensor. Similar to the camera 2, it is composed of a two-dimensional detector formed by an array of photoelectric conversion elements sensitive to visible light or infrared light, such as a CCD or a C-MOS, and an imaging optical system that forms an image of the area to be photographed on the two-dimensional detector. The driver monitoring camera 3 may further have a light source for illuminating the driver, such as an infrared LED. And the driver monitoring camera 3 is attached toward the driver, for example, on the instrument panel or in its vicinity, so that the head of the driver sitting on the driver's seat of the vehicle 10 is included in the photographed area, that is, so that the head of the driver can be photographed. Then, the driver monitoring camera 3 photographs the driver at a predetermined photographing cycle (for example, 1 / 30 second to 1 / 10 second) and generates an image of the driver (hereinafter referred to as a driver image). The driver image obtained by the driver monitoring camera 3 is an example of an in-vehicle sensor signal representing the situation inside the vehicle cabin of the vehicle 10, and may be a color image or a gray image. Each time the driver monitoring camera 3 generates a driver image, it outputs the generated driver image to the ECU 9 via the in-vehicle network.

[0016] The GPS receiver 4 receives GPS signals from GPS satellites at a predetermined cycle and measures the self-position of the vehicle 10 based on the received GPS signals. Then, the GPS receiver 4 outputs positioning information representing the measurement result of the self-position of the vehicle 10 based on the GPS signals to the ECU 9 via the in-vehicle network at a predetermined cycle. Note that the vehicle 10 may have a receiver that receives positioning signals from satellites by another satellite positioning system instead of the GPS receiver to measure the self-position of the vehicle 10.

[0017] The behavior sensor 5 is a sensor for detecting the behavior of the vehicle 10, and includes at least a torque sensor that detects the torque applied to the drive shaft of the drive wheels and an acceleration sensor that detects the acceleration of the vehicle 10. Further, the vehicle control system 1 may have a plurality of different types of behavior sensors 5. For example, the behavior sensor 5 may have a speed sensor or a gyro sensor. And each time the behavior sensor 5 generates a sensor signal representing the behavior of the vehicle 10, the generated sensor signal is output to the ECU 9. Note that the sensor signal generated by the behavior sensor 5 (for example, a signal representing the torque generated by the torque sensor, a signal representing the acceleration or deceleration generated by the acceleration sensor, or a signal representing the speed generated by the speed sensor) is an example of a vehicle behavior signal representing the behavior of the vehicle 10.

[0018] The wireless communication terminal 6 performs wireless communication with a wireless base station in accordance with a predetermined mobile communication standard. The wireless communication terminal 6 receives map information including a high-precision map used for automatic driving control from a map server via the wireless base station. And the wireless communication terminal 6 outputs the received map information to the storage device 8 via the in-vehicle network.

[0019] The notification device 7 is provided in the passenger compartment of the vehicle 10 and is a device that gives a predetermined notification to the driver by light, voice, vibration, character display, or image display. For this purpose, the notification device 7 has, for example, at least one of a speaker, a light source, a vibrator, or a display device. And when the notification device 7 receives a notification signal representing a predetermined notification to the driver (for example, a hands-on request or a driving change request) from the ECU 9, it executes the notification to the driver by voice from the speaker, emission or blinking of the light source, vibration of the vibrator, or display of a message on the display device. When the notification device 7 has two or more types of devices, the notification may be given to the driver via each of the two or more types of devices.

[0020] The storage device 8 is an example of a storage unit and has, for example, a hard disk device, a non-volatile semiconductor memory, or an optical recording medium and its access device. And the storage device 8 stores a high-precision map.

[0021] Furthermore, the storage device 8 has a processor for executing processes such as update processing of map information and processing related to a request for reading a high-precision map from the ECU 9. For example, every time the vehicle 10 moves a predetermined distance, the storage device 8 transmits a request for acquiring map information to the map server via the wireless communication terminal 6 together with the current position of the vehicle 10. Then, the storage device 8 receives map information including a high-precision map for a predetermined area around the current position of the vehicle 10 from the map server via the wireless communication terminal 6, and stores the high-precision map included in the received map information. Further, when the storage device 8 receives a request for reading a map from the ECU 9, it cuts out a range including the current position of the vehicle 10 and relatively narrower than the above-mentioned predetermined area from the stored high-precision map, and outputs it to the ECU 9 via the in-vehicle network. Note that the high-precision map includes information used for automatic driving control of the vehicle 10, such as the number of lanes for each road section, the width of each lane, the speed limit, road markings such as lane dividing lines, and various road signs.

[0022] The ECU 9 controls the automatic driving of the vehicle 10. Further, when the ECU 9 is executing the automatic driving control of the vehicle 10, it determines whether or not a participation request condition for requesting participation in the driving of the vehicle is satisfied, and when the participation request condition is satisfied, it requests the driver to participate in the driving via the notification device 7.

[0023] Note that the request for participation in driving includes a request to hold the steering wheel (hands-on request) and a request to transfer the control subject to the driver (driving handover request).

[0024] As shown in FIG. 2, the ECU 9 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 separate circuits, or may be integrally configured as one integrated circuit.

[0025] The communication interface 21 has an interface circuit for connecting the ECU 9 to other devices. And each time the communication interface 21 receives an image from the camera 2, it passes the received image to the processor 23. Also, each time the communication interface 21 receives a driver image from the driver monitor camera 3, it passes the received driver image to the processor 23. Furthermore, each time the communication interface 21 receives positioning information from the GPS receiver 4, it passes the positioning information to the processor 23. Additionally, each time the communication interface 21 receives a sensor signal from the behavior sensor 5, it passes the sensor signal to the processor 23. Moreover, the communication interface 21 passes the high-precision map read from the storage device 8 to the processor 23. Additionally, the communication interface 21 outputs the notification signal received from the processor 23 to the notification device 7.

[0026] The memory 22 is another example of a storage unit and has, for example, a volatile semiconductor memory and a non-volatile semiconductor memory. And the memory 22 stores various data used in the vehicle control process executed by the processor 23. For example, the memory 22 stores the image around the vehicle 10 received from the camera 2, the driver image received from the driver monitor camera 3, the positioning information of the vehicle 10 received from the GPS receiver 4, the measured values representing the behavior of the vehicle 10 represented by the sensor signal received from the behavior sensor 5, and the high-precision map read from the storage device 8. Furthermore, the memory 22 stores parameters such as the focal length, shooting direction, and mounting position of the camera 2, and various parameters for identifying the object detector used for detecting ground features and the like. Additionally, the memory 22 temporarily stores various data generated during the vehicle control process.

[0027] The processor 23 includes one or more CPUs (Central Processing Units) and its peripheral circuits. The processor 23 may further include other arithmetic circuits such as a logical arithmetic unit, a numerical arithmetic unit, or a graphic processing unit. And the processor 23 executes vehicle control processing for the vehicle 10 at a predetermined cycle. Further, the processor 23 changes the participation request condition for whether to request the driver to increase the degree of participation in driving according to whether the vehicle 10 is towing a towed vehicle. Further, after starting the lane change process for the vehicle 10, the processor 23 changes the interruption condition for whether to interrupt the lane change process according to whether the vehicle 10 is towing a towed vehicle.

[0028] (First Embodiment) FIG. 3 is a functional block diagram of the processor 23 regarding the vehicle control process according to the first embodiment. The processor 23 includes a towing detection unit 31, a control unit 32, a determination unit 33, and a notification processing unit 34. Each of these units included in the processor 23 is a functional module realized by, for example, a computer program operating on the processor 23. Alternatively, each of these units included in the processor 23 may be a dedicated arithmetic circuit provided in the processor 23.

[0029] In the first embodiment, during the execution of the automatic driving control for the vehicle 10, the processor 23 determines whether the participation request condition is satisfied, and when the participation request condition is satisfied, the processor 23 sends a participation request to request the driver to participate in the driving of the vehicle 10 via the notification device 7. And the processor 23 changes the participation request condition according to whether the towing of the towed vehicle 11 by the vehicle 10 is detected. Hereinafter, the towing of the towed vehicle 11 by the vehicle 10 may be simply referred to as the towing of the towed vehicle 11.

[0030] The traction detection unit 31 detects that the vehicle 10 is towing the towed vehicle 11. It is assumed that whether the vehicle 10 is towing the towed vehicle 11 or not does not change during the operation of the vehicle 10. Therefore, once the traction detection unit 31 determines the detection of the traction of the towed vehicle 11, it may not perform the determination until the ignition switch of the vehicle 10 is turned off.

[0031] For example, when the vehicle 10 is in a predetermined state, the traction detection unit 31 uses a sensor signal representing the measured values of acceleration and torque when the vehicle 10 accelerates, which is obtained from the behavior sensor 5, for the detection of the traction of the towed vehicle 11. Then, the traction detection unit 31 compares the traction determination threshold value corresponding to the torque with the acceleration. When the acceleration is less than the traction determination threshold value, it detects the traction of the towed vehicle 11. On the other hand, when the acceleration is greater than or equal to the traction determination threshold value, the traction detection unit 31 does not detect the traction of the towed vehicle 11. Note that the traction determination threshold value for each torque is stored in advance in the memory 22.

[0032] Also, the predetermined state can be, for example, a state where the vehicle 10 is stopped at a point without a gradient in its traveling direction, or a state where the vehicle 10 is traveling at a constant speed on a road without a gradient in its traveling direction. Then, the traction detection unit 31 can determine the presence or absence of a gradient in the traveling direction of the vehicle 10 by referring to the position of the vehicle 10 indicated by the latest positioning signal from the GPS receiver 4 and the high-precision map. Further, when there is no gradient in the traveling direction of the vehicle 10, the traction detection unit 31 can determine whether the vehicle 10 is in a predetermined state based on the sensor signal representing the speed of the vehicle 10, which is obtained from a speed sensor, which is an example of the behavior sensor 5.

[0033] Furthermore, when the traction detection unit 31 detects the traction of the towed vehicle 11, it may estimate the weight of the towed vehicle 11. In this case, the traction detection unit 31 refers to a reference table representing the relationship between torque, acceleration, and the weight of the towed vehicle 11 to identify the weight corresponding to the measured torque and acceleration, and may set the identified weight as the estimated weight of the towed vehicle 11.

[0034] Further, when a sensor for detecting that the towed vehicle 11 is connected is provided in the equipment for towing the towed vehicle 11, the towing detection unit 31 may detect the towing of the towed vehicle 11 when the sensor signal from the sensor indicates that the towed vehicle 11 is connected.

[0035] The towing detection unit 31 notifies the control unit 32 and the determination unit 33 of the determination result of whether or not the towing of the towed vehicle 11 is detected.

[0036] The control unit 32 controls the running of the vehicle 10 with reference to the high-precision map read from the storage device 8. For example, the control unit 32 controls each part of the vehicle 10 so that the vehicle 10 continues to run within its own lane. At that time, the control unit 32 creates a planned travel route passing within its own lane with reference to the high-precision map used for travel control. For example, the control unit 32 creates a planned travel route so as to pass through the center between two lane dividing lines that demarcate its own lane shown in the high-precision map. Then, the control unit 32 controls each part of the vehicle 10 so that the vehicle 10 runs along the planned travel route.

[0037] Therefore, the control unit 32 detects the position of the vehicle 10 at a predetermined cycle, and compares the detected position of the vehicle 10 with the planned travel route. In order to accurately detect the position of the vehicle 10, the control unit 32 collates the image generated by the camera 2 with the high-precision map used for travel control. For example, the control unit 32 projects the features on or around the road detected from the image onto the high-precision map, or projects the features on or around the road around the vehicle 10 represented on the high-precision map onto the image, assuming the position and orientation of the vehicle 10. The features on or around the road can be, for example, road markings such as lane dividing lines or stop lines, or curbstones. Then, the control unit 32 detects the position and orientation of the vehicle 10 when the features detected from the image and the features represented on the high-precision map match the most as the accurate position of the vehicle 10. Further, the control unit 32 detects the lane including its own position on the high-precision map as the own lane. Furthermore, the control unit 32 sets the lane dividing line detected at the position closest to the vehicle 10 in the regions corresponding to the left and right sides of the vehicle 10 on the image as the lane dividing line that divides the own lane.

[0038] The control unit 32 may determine the position where the feature is projected on the high-precision map or the image using the initial values of the assumed position and orientation of the vehicle 10 and the parameters of the camera 2 such as the focal length, the installation height, and the shooting direction. As the initial values of the position and orientation of the vehicle 10, the latest position of the vehicle 10 measured by the GPS receiver 4, or the position and orientation of the vehicle 10 estimated at the previous self-position detection and corrected using the odometry information are used. Then, the control unit 32 calculates the degree of coincidence (for example, the reciprocal of the sum of the squares of the distances between the corresponding features) between the features on or around the road detected from the image and the corresponding features represented on the high-precision map.

[0039] The control unit 32 repeats the above process while changing the assumed position and orientation of the vehicle 10. Then, the control unit 32 may detect the assumed position and orientation when the degree of coincidence is maximized as the accurate position of the vehicle 10.

[0040] Note that the control unit 32 may detect the position of the vehicle 10 without using a high-precision map. In this case, the control unit 32 inputs the image obtained by the camera 2 into an identifier to detect the left and right lane dividing lines that demarcate the own lane represented in the image. Note that the position of the lane dividing line on the image corresponds one-to-one with the azimuth as seen from the camera that generated the image. Therefore, the control unit 32 estimates the position of the lane dividing line corresponding to the reference position on the image with respect to the camera 2 for each of the left and right lane dividing lines based on the reference position in the horizontal direction of the pixels representing the left and right lane dividing lines at the position closest to the bottom end of the image, and parameters such as the focal length, shooting direction, and installation height of the camera 2. Further, the control unit 32 may measure the lateral position of the vehicle 10 within the own lane by obtaining the distance from the camera 2 to each of the left and right lane dividing lines based on the estimation result and the extension direction of the lane dividing line and the shooting direction of the camera 2. The control unit 32 may detect a feature object to be detected by inputting the image into an identifier that has been pre-trained to detect the feature object from the image. As such an identifier, the control unit 32 may use a deep neural network (DNN) having a convolutional neural network (CNN) type architecture such as Single Shot MultiBox Detector or Faster R-CNN. Alternatively, the control unit 32 may use a DNN having a self attention network (SAN) type architecture such as Vision Transformer as such an identifier. Alternatively, the control unit 32 may use an identifier based on another machine learning method such as an AdaBoost identifier as such an identifier. Such an identifier is pre-trained according to a predetermined learning method such as the error backpropagation method using a large number of teacher images representing the feature object so as to detect the feature object to be detected from the image.

[0041] Note that the control unit 32 may measure the position of the vehicle 10 without using a high-precision map. In this case, the control unit 32 inputs the image obtained by the camera 2 into an identifier to detect the left and right lane dividing lines that demarcate the own lane represented in the image. Note that the position of the lane dividing line on the image corresponds one-to-one with the azimuth as seen from the camera that generated the image. Therefore, the control unit 32 estimates the position of the lane dividing line corresponding to the reference position on the image with respect to the camera 2 for each of the left and right lane dividing lines based on the reference position in the horizontal direction of the pixels representing the left and right lane dividing lines at the position closest to the bottom end of the image, and parameters such as the focal length, shooting direction, and installation height of the camera 2. Further, the control unit 32 may measure the lateral position of the vehicle 10 within the own lane by obtaining the distance from the camera 2 to each of the left and right lane dividing lines based on the estimation result and the extension direction of the lane dividing line and the shooting direction of the camera 2.

[0042] If the measured position of the vehicle 10 is on the planned travel route, the control unit 32 determines the steering angle of the vehicle 10 so that the vehicle 10 advances along the planned travel route, and controls the steering of the vehicle 10 so that the determined steering angle is achieved. Also, if the measured position of the vehicle 10 is away from the planned travel route, the control unit 32 determines the steering angle of the vehicle 10 so that the vehicle 10 approaches the planned travel route, and controls the steering of the vehicle 10 so that the determined steering angle is achieved.

[0043] Furthermore, the control unit 32 refers to the current position of the vehicle 10 and the high-precision map to identify the speed limit of the road on which the vehicle 10 is traveling, and sets the identified speed limit as the target vehicle speed. Then, the control unit 32 controls each part of the vehicle 10 so that the speed of the vehicle 10 approaches the set target vehicle speed. Also, the control unit 32 controls the acceleration and deceleration of the vehicle 10 so that the inter-vehicle distance between the preceding vehicle traveling ahead of the vehicle 10 in the own lane and the vehicle 10 is maintained at a certain interval or more. For this purpose, the control unit 32 inputs the image obtained by the camera 2 into an identifier that has been pre-learned to detect other vehicles, thereby detecting other vehicles traveling around the vehicle 10. As such an identifier, the control unit 32 can use an identifier similar to the identifier used for detecting ground objects. Alternatively, the identifier used for detecting ground objects may be pre-learned to also detect other vehicles. In this case, the control unit 32 can detect not only ground objects but also other vehicles by inputting the image into the identifier used for detecting ground objects. Then, among the detected other vehicles, the control unit 32 may regard as the preceding vehicle the other vehicle whose lower end is located within the area sandwiched between two lane dividing lines that demarcate the own lane in the image. Furthermore, the control unit 32 may estimate the distance between the vehicle 10 and the preceding vehicle based on the position of the lower end of the object area representing the preceding vehicle in the image and parameters such as the shooting direction, focal length, and installation height of the camera 2. Then, if the estimated distance to the preceding vehicle is less than a certain interval, the control unit 32 sets the acceleration and deceleration of the vehicle 10 so as to decelerate the vehicle 10. On the other hand, if the estimated distance to the preceding vehicle is a certain interval or more, the control unit 32 sets the acceleration and deceleration of the vehicle 10 so that the speed of the vehicle 10 approaches the target speed.

[0044] When the acceleration / deceleration speed is set as described above, the control unit 32 sets the accelerator opening or the brake amount according to the set acceleration / deceleration speed. At this time, the control unit 32 may change the accelerator opening or the brake amount depending on whether the towing of the towed vehicle 11 is detected or not. For example, the control unit 32 may make the accelerator opening or the brake amount when the towing of the towed vehicle 11 is detected larger than the accelerator opening or the brake amount when the towing of the towed vehicle 11 is not detected.

[0045] The control unit 32 obtains the fuel injection amount according to the set accelerator opening, and outputs a control signal corresponding to the fuel injection amount to the fuel injection device of the engine of the vehicle 10. Alternatively, the control unit 32 obtains the amount of electric power supplied to the motor according to the set accelerator opening, and controls the drive circuit of the motor so that the amount of electric power is supplied to the motor. Alternatively, the control unit 32 outputs a control signal corresponding to the set brake amount to the brake of the vehicle 10.

[0046] In addition, if the driver does not perform the required participation even after a predetermined period has elapsed since the request for the driver's participation in driving is notified, the control unit 32 may stop the automatic driving control or stop the vehicle 10. For example, if the ECU 9 does not receive a signal indicating that the steering wheel is held from a touch sensor (not shown) provided on the steering wheel even after a predetermined period has elapsed since the hands-on request is notified, the control unit 32 may stop the automatic driving control and transfer the driving control to the driver. Also, if the ECU 9 does not receive a signal indicating that the steering wheel is held from the touch sensor provided on the steering wheel, or a signal indicating that the steering wheel, accelerator, or brake has been operated even after a predetermined period has elapsed since the driving handover request is notified, the control unit 32 may stop the vehicle 10.

[0047] The determination unit 33 determines whether the participation requirement condition is satisfied. In the present embodiment, the determination unit 33 compares the distances from the vehicle 10 to the left and right lane dividing lines that demarcate the own lane (hereinafter referred to as the lateral distances) with the hands-on requirement threshold value. And if any of the lateral distances on the left and right is less than the hands-on requirement threshold value, the determination unit 33 determines that the participation requirement condition is satisfied. And when the determination unit 33 determines that the participation requirement condition is satisfied, it notifies the determination result to the notification processing unit 34. The hands-on requirement threshold value is an example of a distance threshold value.

[0048] Here, the determination unit 33 sets the hands-on requirement threshold value when the towing of the towed vehicle 11 is detected to a larger value than the hands-on requirement threshold value when the towing of the towed vehicle 11 is not detected. That is, the participation requirement condition when the towing of the towed vehicle 11 is detected is relaxed compared to the participation requirement condition when the towing of the towed vehicle 11 is not detected. For example, the determination unit 33 sets the hands-on requirement threshold value when the towing of the towed vehicle 11 is not detected to 0.2 m to 0.3 m, and sets the hands-on requirement threshold value when the towing of the towed vehicle 11 is detected to 0.4 m to 0.5 m. By setting the hands-on requirement threshold value in this way, even when the vehicle 10 is towing the towed vehicle 11, it becomes possible to request the driver to hold the steering wheel before the vehicle 10 gets too close to the lane dividing line.

[0049] Note that, as described in the control unit 32, the determination unit 33 may estimate the position of the lane dividing line with reference to the camera 2 based on the position of the lane dividing line detected from the image on the image and the parameters of the camera 2. Further, the determination unit 33 may obtain the lateral distance by subtracting the distance from the mounting position of the camera 2 to the side surface of the vehicle 10 from the distance from the camera 2 to the lane dividing line for each of the left and right sides of the vehicle 10.

[0050] Figures 4(a) and 4(b) are diagrams showing an example of the relationship between the hands-on request threshold when the towing of the towed vehicle 11 is not detected and the hands-on request threshold when the towing of the towed vehicle 11 is detected. In the example shown in Figure 4(a), the vehicle 10 is not towing another vehicle. In contrast, in the example shown in Figure 4(b), the vehicle 10 is towing the towed vehicle 11.

[0051] As shown in Figure 4(a), when the towing of the towed vehicle 11 is not detected, the first value HOnTh1 is used as the hands-on request threshold. Therefore, when the towing of the towed vehicle 11 is not detected, if the lateral distance L between either the left or right lane dividing line 401 and the vehicle 10 becomes less than the hands-on request threshold HOnTh1, it is determined that the participation request condition is satisfied, and a hands-on request is notified.

[0052] In contrast, as shown in Figure 4(b), when the towing of the towed vehicle 11 is detected, the second value HOnTh2 is used as the hands-on request threshold. Therefore, when the towing of the towed vehicle 11 is detected, if the lateral distance L between either the left or right lane dividing line 401 and the vehicle 10 becomes less than the hands-on request threshold HOnTh2, it is determined that the participation request condition is satisfied, and a hands-on request is notified. Also, the second value HOnTh2 is set to a value larger than the first value HOnTh1. Therefore, it is easier for the participation request condition to be satisfied when the towing of the towed vehicle 11 is detected than when the towing of the towed vehicle 11 is not detected. Therefore, even when the vehicle 10 is towing the towed vehicle 11, a hands-on request will be notified before the vehicle 10 gets too close to the lane dividing line 401.

[0053] Also, the determination unit 33 compares the lateral distances to the left and right lane dividing lines with the driving handover request threshold. And if either of the lateral distances to the left and right is less than the driving handover request threshold, the determination unit 33 determines that the participation request condition is satisfied. The driving handover request threshold is another example of a distance threshold.

[0054] When the determination unit 33 detects no towing of the towed vehicle 11, it sets the driving handover request threshold value when the towing of the towed vehicle 11 is detected to a larger value than the driving handover request threshold value when no towing of the towed vehicle 11 is detected. For example, the determination unit 33 sets the driving handover request threshold value when no towing of the towed vehicle 11 is detected to 0.1 m to 0.2 m, and sets the driving handover request threshold value when the towing of the towed vehicle 11 is detected to 0.2 m to 0.3 m. By setting the driving handover request threshold value in this way, even when the vehicle 10 is towing the towed vehicle 11, the determination unit 33 can transfer the driving control to the driver before the vehicle 10 gets too close to the lane dividing line.

[0055] FIG. 5(a) and FIG. 5(b) are diagrams showing an example of the relationship between the driving handover request threshold value when no towing of the towed vehicle 11 is detected and the driving handover request threshold value when towing of the towed vehicle 11 is detected. In the example shown in FIG. 5(a), no towing of the towed vehicle 11 is detected. In contrast, in the example shown in FIG. 5(b), towing of the towed vehicle 11 is detected.

[0056] As shown in FIG. 5(a), when no towing of the towed vehicle 11 is detected, a first value TDTh1 is used as the driving handover request threshold value. Therefore, when no towing of the towed vehicle 11 is detected, when the lateral distance L between either the left or right lane dividing line 501 and the vehicle 10 becomes less than the driving handover request threshold value TDTh1, it is determined that the participation request condition is satisfied, and a driving handover request is notified.

[0057] On the other hand, as shown in FIG. 5(b), when the towing of the towed vehicle 11 is detected, the second value TDTh2 is used as the driving change request threshold. Therefore, when the towing of the towed vehicle 11 is detected, if the lateral distance L between either the left or right lane dividing line 501 and the vehicle 10 becomes less than the driving change request threshold TDTh2, it is determined that the participation request condition is satisfied, and a driving change request is notified. Also, the second value TDTh2 is set to a value larger than the first value TDTh1. Therefore, it is easier for the participation request condition to be satisfied when the towing of the towed vehicle 11 is detected than when the towing of the towed vehicle 11 is not detected. Therefore, even when the vehicle 10 is towing the towed vehicle 11, a driving change request will be notified before the vehicle 10 gets too close to the lane dividing line 501.

[0058] When the notification processing unit 34 receives from the determination unit 33 a determination result that the participation request condition is satisfied, it notifies the driver of the request corresponding to the satisfied participation request condition via the notification device 7.

[0059] As described above, when it is determined that the lateral distance has become less than the hands-on request threshold, the notification processing unit 34 notifies the driver of a hands-on request via the notification device 7. Also, when it is determined that the lateral distance has become less than the driving change request threshold, the notification processing unit 34 notifies the driver of a driving change request via the notification device 7.

[0060] FIG. 6 is an operation flowchart of vehicle control processing regarding the change in the degree of driver's driving participation according to the first embodiment. The processor 23 may execute vehicle control processing according to the following operation flowchart at a predetermined cycle.

[0061] The towing detection unit 31 of the processor 23 determines whether it has detected the towing of the towed vehicle 11 by the vehicle 10 (step S101).

[0062] When the towing of the towed vehicle 11 is not detected (step S101 - No), the determination unit 33 of the processor 23 sets the participation request conditions relatively strictly (step S102). On the other hand, when the towing of the towed vehicle 11 is detected (step S101 - Yes), the determination unit 33 sets the participation request conditions relatively loosely (step S103).

[0063] The determination unit 33 determines whether the set participation request conditions are satisfied (step S104). When the participation request conditions are satisfied (step S104 - Yes), the notification processing unit 34 of the processor 23 notifies the driver of the request regarding participation in driving corresponding to the satisfied participation request conditions via the notification device 7 (step S105).

[0064] When the participation request conditions are not satisfied in step S104 (step S104 - No), or after step S105, the processor 23 ends the vehicle control process.

[0065] As described above, this vehicle control device determines whether the participation request conditions for requesting the driver of the vehicle to participate in driving are satisfied, and when it is determined that the participation request conditions are satisfied, it notifies the request for participation in driving via the notification device provided in the vehicle interior. And this vehicle control device relaxes the participation request conditions when the towing of the towed vehicle is detected compared to the participation request conditions when the towing of the towed vehicle is not detected. Therefore, when the towing of the towed vehicle is detected, it becomes easier for the participation request conditions to be satisfied. Thus, even when the vehicle is towing a towed vehicle, this vehicle control device can request the driver to participate in driving before the vehicle falls into an unstable situation. As a result, this vehicle control device can appropriately set the timing to increase the degree of the driver's participation in driving of a vehicle that is towing a towed vehicle and to which autonomous driving control is applied.

[0066] According to a modified example, when the towing of the towed vehicle 11 is detected, the determination unit 33 may adjust the hands-on request threshold or the driving change request threshold according to the weight of the towed vehicle 11. For example, the determination unit 33 may increase the hands-on request threshold or the driving change request threshold as the weight of the towed vehicle 11 estimated by the towing detection unit 31 is larger. At that time, as the estimated weight of the towed vehicle 11 increases, the hands-on request threshold or the driving change request threshold may also increase continuously. Alternatively, the hands-on request threshold or the driving change request threshold may be set stepwise. In this case, each time the estimated weight of the towed vehicle 11 increases by a predetermined value, the determination unit 33 increases the hands-on request threshold or the driving change request threshold by a predetermined step amount.

[0067] Similarly, when the towing of the towed vehicle 11 is detected, the determination unit 33 may adjust the hands-on request threshold or the driving change request threshold according to the volume of the towed vehicle 11. For example, the determination unit 33 may increase the hands-on request threshold or the driving change request threshold as the volume of the towed vehicle 11 estimated by the towing detection unit 31 is larger. In this case, the information representing the volume of the towed vehicle 11 may be stored in advance in the memory 22.

[0068] In this way, by adjusting the hands-on request threshold or the driving change request threshold according to the weight or volume of the towed vehicle 11, the determination unit 33 can request the driver to participate in driving at a more appropriate timing before the vehicle 10 gets too close to the lane dividing line.

[0069] Furthermore, when the towing of the towed vehicle 11 is detected, the determination unit 33 may adjust the hands-on request threshold or the driving change request threshold according to the type of the load carried on the towed vehicle 11. For example, when the type of the load carried on the towed vehicle 11 is an item requiring special handling that is relatively vulnerable to vibration or impact, such as precision machinery or fragile items, the hands-on request threshold in this case may be set larger than the hands-on request threshold when the type of the load is not an item requiring special handling. Similarly, the determination unit 33 may set the driving change request threshold when the type of the load carried on the towed vehicle 11 is an item requiring special handling larger than the driving change request threshold when the type of the load is not an item requiring special handling. Note that the information indicating the type of the load on the towed vehicle 11 is input via a user interface provided in the vehicle interior of the vehicle 10 and stored in the memory 22. The determination unit 33 may determine the type of the load on the towed vehicle 11 by referring to the information.

[0070] Furthermore, when the towing of the towed vehicle 11 is detected, the lower the certainty of the lane dividing line that demarcates the own lane detected, the larger the hands-on request threshold or the driving change request threshold may be set. In this case, the determination unit 33 may use the reliability of the lane dividing line output by the identifier used for detecting the lane dividing line as the above-mentioned certainty.

[0071] According to another modification, instead of the lateral distance, the determination unit 33 may determine whether the participation request condition is satisfied based on the behavior of the vehicle 10, the state of the driver, or the situation around the vehicle 10. Also in this case, it is preferable that the determination unit 33 relaxes the participation request condition when the towing of the towed vehicle 11 is detected compared to the participation request condition when the towing of the towed vehicle 11 is not detected. By relaxing the participation request condition when the towing of the towed vehicle 11 is detected in this way, even when the vehicle 10 is towing the towed vehicle 11, the determination unit 33 can request the driver to participate in driving before the vehicle 10 falls into an unstable situation due to the behavior of the vehicle 10, the state of the driver, or the situation around the vehicle 10.

[0072] For example, when the speed of the vehicle 10 measured by a speed sensor, which is an example of the behavior sensor 5, is equal to or higher than a predetermined speed threshold than the speed limit of the road on which the vehicle 10 is currently traveling, the determination unit 33 determines that the participation requirement condition is satisfied. Then, the notification processing unit 34 notifies the driver of a hands-on requirement via the notification device 7. In this case, the determination unit 33 sets the speed threshold when the towing of the towed vehicle 11 is detected to a value lower than the speed threshold when the towing of the towed vehicle 11 is not detected. Thereby, the determination unit 33 can appropriately request the driver to participate in driving when the speed of the vehicle 10 exceeds the speed limit. Note that the determination unit 33 refers to the high-precision map and identifies the road including the position of the vehicle 10 represented by the latest positioning information by the GPS receiver 4 as the road on which the vehicle 10 is traveling. Then, the determination unit 33 may refer to the high-precision map to identify the speed limit of the road on which the vehicle 10 is traveling. Alternatively, the determination unit 33 may identify the speed limit of the road on which the vehicle 10 is traveling by inputting the image generated by the camera 2 into an identifier that has been pre-learned to detect the speed limit represented by the speed sign. The determination unit 33 can use, as such an identifier, the same identifier as the identifier used for detecting ground features described in the control unit 32.

[0073] Also, when the vehicle 10 is traveling in a section where the speed limit is less than a predetermined speed, the determination unit 33 determines that the participation requirement condition is satisfied. Then, the notification processing unit 34 notifies the driver of a hands-on requirement via the notification device 7. In this case, the determination unit 33 sets the predetermined speed when the towing of the towed vehicle 11 is detected to be higher than the predetermined speed when the towing of the towed vehicle 11 is not detected. Thereby, the determination unit 33 can appropriately request the driver to participate in driving when the speed limit of the road on which the vehicle 10 is traveling is low and more careful control of the vehicle 10 is required.

[0074] Alternatively, when the radius of curvature of a curve located within a section where the vehicle 10 is traveling or within a section up to a predetermined distance (for example, several hundred meters to 1 km) ahead is less than a predetermined radius-of-curvature threshold value, the determination unit 33 determines that the participation requirement condition is satisfied. When the radius of curvature of the curve is less than the predetermined radius-of-curvature threshold value, the notification processing unit 34 notifies the driver of a hands-on requirement via the notification device 7. Alternatively, the notification processing unit 34 may notify the driver of a driving change requirement via the notification device 7. In this case, the determination unit 33 sets the radius-of-curvature threshold value in the case where the towing of the towed vehicle 11 is detected to a value larger than the radius-of-curvature threshold value in the case where the towing of the towed vehicle 11 is not detected. Thereby, the determination unit 33 can appropriately request the driver's participation in driving according to the radius of curvature of the curve on which the vehicle 10 is traveling or is scheduled to travel. Note that, in the same manner as described above, the determination unit 33 may specify, with reference to the high-precision map, the road including the position of the vehicle 10 represented by the latest positioning information by the GPS receiver 4 as the road on which the vehicle 10 is traveling. Further, the determination unit 33 may specify the radius of curvature of a curve included in a section from the current position of the vehicle 10 to a predetermined distance ahead on the road on which the vehicle 10 is traveling, with reference to the traveling direction of the vehicle 10 indicated by an azimuth sensor (not shown) mounted on the vehicle 10 and the high-precision map being used for travel control.

[0075] Alternatively, when the vehicle is traveling or the slope of the road in the section up to a predetermined distance ahead is equal to or greater than a predetermined slope threshold value, the determination unit 33 determines that the participation requirement condition is satisfied. Then, the notification processing unit 34 notifies the driver of a hands-on requirement via the notification device 7. Alternatively, the notification processing unit 34 may notify the driver of a driving change requirement via the notification device 7. In this case, the determination unit 33 sets the slope threshold value when the towing of the towed vehicle 11 is detected to a value smaller than the slope threshold value when the towing of the towed vehicle 11 is not detected. Thereby, the determination unit 33 can appropriately request the driver to participate in driving according to the slope of the road section on which the vehicle 10 is traveling or is planned to travel. Note that, in the same manner as described above, the determination unit 33 may refer to the high-precision map and specify the road including the position of the vehicle 10 represented by the latest positioning information by the GPS receiver 4 as the road on which the vehicle 10 is traveling. Further, the determination unit 33 may specify the traveling direction of the vehicle 10 indicated by an azimuth sensor (not shown) mounted on the vehicle 10 and the slope in the section from the current position of the vehicle 10 to a predetermined distance ahead on the road on which the vehicle 10 is traveling with reference to the high-precision map.

[0076] Alternatively, when the unheld period during which the driver does not hold the steering wheel continues for a predetermined unheld period threshold value or more, the determination unit 33 determines that the participation requirement condition is satisfied. Then, the notification processing unit 34 notifies the driver of a hands-on requirement via the notification device 7. In this case, the unheld period threshold value when the towing of the towed vehicle 11 is detected is set to a value smaller than the unheld period threshold value when the towing of the towed vehicle 11 is not detected. Note that the determination unit 33 may set the elapsed time since the ECU 9 last received a signal indicating that the steering wheel is being held from a touch sensor provided on the steering wheel as the unheld period.

[0077] Alternatively, when the period during which the driver ignores any of the face loss warning, side glance warning, eyes closed warning, or hand release warning made via the notification device 7 continues for a predetermined time threshold or more, the determination unit 33 determines that the participation request condition is satisfied. Then, the notification processing unit 34 notifies the driver of a hands-on request via the notification device 7. In this case, the time threshold when the towing of the towed vehicle 11 is detected is set to a value smaller than the time threshold when the towing of the towed vehicle 11 is not detected.

[0078] Note that the determination unit 33 determines whether or not a face region in which the driver's face is represented on the driver image can be detected by inputting the driver image generated by the driver monitoring camera 3 into an identifier that has been pre-learned to detect the driver's face. The determination unit 33 can use, as such an identifier, the same identifier as the identifier used by the control unit 32 for detecting ground features. When the face region is not detected, the determination unit 33 determines that it is a face loss state in which the driver's face cannot be detected. When the face loss state continues for a predetermined period, the determination unit 33 notifies the driver of a face loss warning via the notification device 7. If the driver's face is detected from the driver image generated after the notification of the face loss warning, or if the driver performs a response operation corresponding to the face loss warning provided in the passenger compartment, the determination unit 33 determines that the driver has responded to the face loss warning. On the other hand, if the driver's face is not detected from the driver image even after the notification of the face loss warning and no response operation to the face loss warning is performed, the determination unit 33 may determine that the driver has ignored the face loss warning. Note that the response operation may be executed, for example, by operating a predetermined switch provided in the passenger compartment or by the driver making a predetermined utterance. The voice uttered by the driver is collected by a speaker provided in the passenger compartment and output as a voice signal to the ECU 9. The processor 23 may determine whether or not the driver has made a predetermined utterance by performing predetermined voice recognition processing such as GMM-HMM or DNN-HMM on the voice signal.

[0079] Further, the determination unit 33 determines the orientation of the driver's face by matching the face region with a three-dimensional face model. When the orientation of the driver's face deviates from a predetermined angular range centered on the traveling direction of the vehicle 10, the determination unit 33 determines that the driver is in a side-looking state of looking sideways. Alternatively, the determination unit 33 may detect the line-of-sight direction of the driver and determine that it is a side-looking state when the detected line-of-sight direction deviates from the above angular range. In this case, the determination unit 33 applies an edge detection filter to the face region to detect edges continuous in the horizontal direction, or inputs the face region to a discriminator to detect the upper and lower eyelids of either the left or right eye of the driver. Further, the determination unit 33 executes template matching on the region surrounded by the upper and lower eyelids to detect the pupil centroid and the corneal reflection image of the light source. Then, the determination unit 33 may detect the line-of-sight direction based on the positional relationship between the pupil centroid and the corneal reflection image of the light source. When the side-looking state continues for a predetermined period, the determination unit 33 notifies the driver of a side-looking warning via the notification device 7. When the orientation of the driver's face or the line-of-sight direction detected after the notification of the side-looking warning comes to be included in the above angular range, that is, when the side-looking state is resolved, the determination unit 33 determines that the driver has responded to the side-looking warning. On the other hand, if the side-looking state is not resolved even after the notification of the side-looking warning, the determination unit 33 may determine that the driver has ignored the side-looking warning.

[0080] Furthermore, the determination unit 33 calculates the ratio of the detected distance between the upper eyelid and the lower eyelid to the reference distance between the upper eyelid and the lower eyelid when the driver has fully opened their eyes as the eye closure degree. The reference distance is stored in advance in the memory 22. Then, when the eye closure degree is equal to or less than a predetermined eye closure threshold value, the determination unit 33 determines that the driver is in a closed-eye state with their eyes closed. When the closed-eye state continues for a predetermined period, the determination unit 33 notifies the driver of a closed-eye warning via the notification device 7. When the eye closure degree of the driver detected after the notification of the closed-eye warning becomes greater than the eye closure threshold value, that is, when the closed-eye state is resolved, the determination unit 33 determines that the driver has responded to the closed-eye warning. On the other hand, if the closed-eye state is not resolved even after the notification of the closed-eye warning, the determination unit 33 may determine that the driver has ignored the closed-eye warning.

[0081] Also, when the ECU 9 receives a signal indicating that the steering wheel is not being held from a touch sensor provided on the steering wheel, the determination unit 33 determines that the driver is in a released state where they are not holding the steering wheel. And when the released state continues for a predetermined time or more in a state where the ECU 9 is automatically controlling the vehicle 10 at a level where holding of the steering wheel by the driver is required, the determination unit 33 notifies the driver of a released warning via the notification device 7. When the ECU 9 receives a signal indicating that the steering wheel is being held from the touch sensor after the notification of the released warning, the determination unit 33 determines that the released state has been resolved. On the other hand, if the ECU 9 does not receive a signal indicating that the steering wheel is being held from the touch sensor even after the notification of the released warning, the determination unit 33 may determine that the driver has ignored the released warning.

[0082] The determination unit 33 may determine whether all of the participation requirement conditions in the above-described embodiment or modification are satisfied, or may determine whether any one or two or more of those participation requirement conditions are satisfied.

[0083] (Second Embodiment) Next, a second embodiment will be described. In the second embodiment, after the processor 23 starts the lane change process for the vehicle 10, the interruption condition for whether to interrupt the lane change process is changed according to whether the vehicle 10 is towing a towed vehicle.

[0084] FIG. 7 is a functional block diagram of the processor 23 regarding the vehicle control process according to the second embodiment. The processor 23 includes a towing detection unit 31, a lane change determination unit 35, an other vehicle detection unit 36, a lane change control unit 37, a determination unit 38, and an interruption instruction unit 39. Each of these units included in the processor 23 is, for example, a functional module realized by a computer program operating on the processor 23. Alternatively, each of these units included in the processor 23 may be a dedicated arithmetic circuit provided in the processor 23. Also, for those performing the same processing in the first embodiment and the second embodiment, the same reference numerals are given in the first embodiment and the second embodiment. Further, for the details of those corresponding ones among these units in the second embodiment that exist in the first embodiment, refer to the description of the first embodiment.

[0085] The towing detection unit 31 detects, in the same manner as in the first embodiment, that the vehicle 10 is towing the towed vehicle 11. Then, the towing detection unit 31 notifies the lane change control unit 37 and the determination unit 38 of the detection result of towing.

[0086] The lane change determination unit 35 determines whether a predetermined condition for applying lane change control to the vehicle 10 is satisfied. For example, when the driver operates the turn signal, the lane change determination unit 35 determines that the predetermined condition is satisfied. Then, the lane change determination unit 35 determines to apply lane change control to an adjacent lane adjacent to the direction indicated by the turn signal with respect to the own lane. Alternatively, the lane change determination unit 35 may determine that the predetermined condition is satisfied and determine to apply lane change control when the own lane is different from the lane toward the destination of the vehicle 10, when overtaking a preceding vehicle, or when returning from the overtaking lane to the traveling lane.

[0087] The lane change determination unit 35 refers to the driving route to the destination of the vehicle 10, the current position of the vehicle 10, and the high-precision map received by the ECU 9 from a navigation device (not shown) in order to determine whether the own lane is different from the lane toward the destination of the vehicle 10. Then, the lane change determination unit 35 determines whether there is a branch point where the lane toward the destination branches from the road on which the vehicle 10 is currently traveling in a section from the current position of the vehicle 10 to a predetermined distance ahead. When there is a branch point, the lane change determination unit 35 determines whether the own lane is different from the lane toward the destination. Then, when the own lane is different from the lane toward the destination, the lane change determination unit 35 determines that lane change control is to be applied one or more times with the lane toward the destination as the target lane. Note that, as described for the control unit 32 in the first embodiment, the lane change determination unit 35 measures the exact position of the vehicle 10 by collating the image generated by the camera 2 with the high-precision map, and among the lanes represented in the high-precision map, the lane including the measured position of the vehicle 10 may be specified as the own lane.

[0088] In addition, when the speed of the vehicle 10 becomes equal to or lower than a predetermined speed threshold value, and a period during which the inter-vehicle distance between the preceding vehicle traveling ahead of the vehicle 10 and the vehicle 10 becomes equal to or shorter than a predetermined distance continues for a predetermined time, the lane change determination unit 35 determines that lane change control is to be applied to overtake the preceding vehicle. Note that the predetermined time can be, for example, several seconds to several tens of seconds. In this case, the lane change determination unit 35 preferably sets an overtaking lane among the lanes adjacent to the own lane as a target lane to be the lane to be changed. The lane change determination unit 35 may specify a peripheral vehicle represented by an object region located within a range corresponding to the front of the vehicle 10 on the image generated by the camera 2 among the peripheral vehicles detected by the other vehicle detection unit 36 as the preceding vehicle. Further, the predetermined speed threshold value is set to a speed obtained by subtracting a predetermined offset value (for example, 10 km / h to 20 km / h) from the legal speed or the speed limit of the road on which the vehicle 10 is traveling. Therefore, the lane change determination unit 35 may set the speed threshold value by specifying the legal speed or the speed limit of the road on which the vehicle 10 is currently traveling with reference to the current position of the vehicle 10 and the high-precision map. Furthermore, the lane change determination unit 35 may obtain the inter-vehicle distance between the vehicle 10 and the preceding vehicle based on the relative positional relationship between the vehicle 10 and the preceding vehicle detected by the other vehicle detection unit 36.

[0089] Furthermore, when the own lane is an overtaking lane and the vehicle 10 has been traveling in the overtaking lane over a recent predetermined period, the lane change determination unit 35 determines that lane change control is to be applied to return the vehicle 10 to the traveling lane. Note that the lane change determination unit 35 may determine whether the own lane is an overtaking lane by referring to the high-precision map. In this case, the lane change determination unit 35 sets any one of the traveling lanes on the road on which the vehicle 10 is traveling as a target lane to be the lane to be changed.

[0090] When the lane change determination unit 35 determines that lane change control is to be applied to the vehicle 10, it notifies the other vehicle detection unit 36, the lane change control unit 37, and the determination unit 38 of the determination result and the direction (right side or left side) of the adjacent lane as the target for the change as viewed from the road on which the vehicle 10 is traveling.

[0091] The other vehicle detection unit 36 detects other vehicles traveling around the vehicle 10 (hereinafter, for convenience of explanation, referred to as surrounding vehicles). Further, the other vehicle detection unit 36 detects the relative position and relative speed between the surrounding vehicle and the vehicle 10. In particular, the other vehicle detection unit 36 detects the relative position and relative speed between the surrounding vehicle traveling in the adjacent lane (hereinafter, may be simply referred to as the adjacent lane) that is the lane change destination and the vehicle 10. For this purpose, the other vehicle detection unit 36 detects the surrounding vehicle by inputting the image acquired from the camera 2 to the discriminator. As such a discriminator, the other vehicle detection unit 36 can use the same discriminator as described in the control unit 32 in the first embodiment. The discriminator outputs information for specifying an object region including the surrounding vehicle detected on the input image and information representing the vehicle type of the detected surrounding vehicle (for example, a passenger car, a large vehicle, a two-wheeled vehicle, etc.).

[0092] When there is a detected surrounding vehicle, the other vehicle detection unit 36 determines whether the surrounding vehicle travels in the adjacent lane. Here, it is assumed that the position of the lower end of the object region including the surrounding vehicle represents the position where the surrounding vehicle is in contact with the road surface. Also, as described above, the position on the image corresponds one-to-one with the orientation seen from the camera that generated the image. Therefore, the other vehicle detection unit 36 can estimate the distance from the camera 2 to the surrounding vehicle and the orientation from the vehicle 10 to the surrounding vehicle by referring to the position of the lower end of the object region on the image and parameters such as the installation height and shooting direction of the camera 2. Alternatively, the other vehicle detection unit 36 may estimate the distance from the camera 2 to the surrounding vehicle based on the reference number of pixels on the image when the inter-vehicle distance is the reference distance, which corresponds to the reference vehicle width corresponding to the vehicle type of the surrounding vehicle, and the horizontal width of the object region including the surrounding vehicle.

[0093] In addition, when the vehicle 10 is equipped with a ranging sensor (not shown), the other vehicle detection unit 36 may detect surrounding vehicles based on the ranging signal. In this case as well, the other vehicle detection unit 36 may detect the surrounding vehicles by inputting the ranging signal to a discriminator that has been pre-trained to detect surrounding vehicles from the ranging signal. As the discriminator for detecting surrounding vehicles from the ranging signal, the other vehicle detection unit 36 can use a DNN having a CNN-type or SAN-type architecture. Alternatively, the other vehicle detection unit 36 may detect the surrounding vehicles according to another method for detecting surrounding vehicles from the ranging signal. In this case, the other vehicle detection unit 36 may regard the direction in which a surrounding vehicle is detected on the ranging signal as the direction from the vehicle 10 to the surrounding vehicle. Also, the other vehicle detection unit 36 may regard the distance indicated by the ranging signal for that direction as the estimated distance from the vehicle 10 to the surrounding vehicle.

[0094] Based on the estimated direction and distance, the other vehicle detection unit 36 estimates the distance from the vehicle 10 to the surrounding vehicle along the direction orthogonal to the traveling direction of the vehicle 10 (hereinafter, for convenience of explanation, referred to as the lateral distance between vehicles). When the lateral distance between vehicles is included within a predetermined distance range corresponding to the width of the adjacent lane at the current position of the vehicle 10, and the direction from the vehicle 10 to the surrounding vehicle is the same as the direction of the adjacent lane to which the lane change destination with respect to the own lane, the other vehicle detection unit 36 determines that the surrounding vehicle is traveling in the adjacent lane. The other vehicle detection unit 36 may specify the predetermined distance range at the current position of the vehicle 10 by referring to the high-precision map.

[0095] Alternatively, the other vehicle detection unit 36 may detect the lane dividing lines represented in the image together with the surrounding vehicles by inputting the image to a discriminator. In this case, the discriminator is pre-trained so that it can also detect the lane dividing lines. Then, the other vehicle detection unit 36 specifies, as the area represented by the adjacent lane in the image, the area sandwiched between two lane dividing lines in order from the one closer to the position of the vehicle 10 in the image in the direction of the merging destination (right or left). When the lower end of the object area representing the surrounding vehicle is included in the area corresponding to the adjacent lane, the other vehicle detection unit 36 may determine that the surrounding vehicle is traveling in the adjacent lane.

[0096] The other vehicle detection unit 36 executes the above processing on a series of time-series images generated by the camera 2 or a series of time-series distance measurement signals generated by the distance measurement sensor, thereby estimating the relative position of the surrounding vehicles with respect to the vehicle 10 at the time of generating each image or each distance measurement signal. Further, the other vehicle detection unit 36 determines the change in the relative position from the relative positions of the surrounding vehicles with respect to the vehicle 10 at the time of generating individual images or distance measurement signals arranged in time series in a recent fixed period, and estimates the relative speed of the surrounding vehicles with respect to the vehicle 10 based on the change in the relative position.

[0097] When a plurality of surrounding vehicles are detected, the other vehicle detection unit 36 may track each individual surrounding vehicle over a series of time-series images or a series of time-series distance measurement signals by applying a predetermined tracking method such as KLT tracking. Then, the other vehicle detection unit 36 may estimate the relative position and relative speed of the surrounding vehicles with respect to the vehicle 10 for each of the surrounding vehicles being tracked.

[0098] The other vehicle detection unit 36 notifies the lane change control unit 37 and the determination unit 38 of the relative position and relative speed of each individual surrounding vehicle traveling in the adjacent lane of the lane change destination with respect to the vehicle 10.

[0099] When the lane change control unit 37 is notified of the determination result that lane change control is to be applied to the vehicle 10 from the lane change determination unit 35, the lane change control unit 37 executes lane change control to cause the vehicle 10 to enter the adjacent lane. Further, before the lane change control is completed, when the lane change control unit 37 is instructed to interrupt the lane change control from the interruption instruction unit 39, the lane change control unit 37 interrupts the execution of the lane change control. Then, the lane change control unit 37 controls each part of the vehicle 10 so that the vehicle 10 continues to travel in its own lane.

[0100] When the lane change control unit 37 starts executing the lane change control, it sets a planned travel route for the vehicle 10 to move from its own lane to an adjacent lane. After setting the planned travel route, the lane change control unit 37 controls each part of the vehicle 10 so that the vehicle 10 travels along the planned travel route. For this purpose, the lane change control unit 37 measures the position of the vehicle 10 at a predetermined cycle, and compares the measured position of the vehicle 10 with the planned travel route. Note that, as described for the control unit 32 in the first embodiment, the lane change control unit 37 may measure the accurate position of the vehicle 10 by collating the image obtained by the camera 2 with the high-precision map. And if the measured position of the vehicle 10 is on the planned travel route, the lane change control unit 37 determines the steering angle of the vehicle 10 so that the vehicle 10 advances along the planned travel route, and controls the steering of the vehicle 10 so that it becomes the determined steering angle. Also, if the measured position of the vehicle 10 is away from the planned travel route, the lane change control unit 37 determines the steering angle of the vehicle 10 so that the vehicle 10 approaches the planned travel route, and controls the steering of the vehicle 10 so that it becomes the determined steering angle.

[0101] Furthermore, when there are surrounding vehicles traveling in front of or to the side of the vehicle 10 in the adjacent lane, the lane change control unit 37 sets the acceleration and deceleration of the vehicle 10 so that the distance between the surrounding vehicle and the vehicle 10 becomes equal to or greater than a predetermined distance threshold when the vehicle 10 enters the adjacent lane. At this time, the lane change control unit 37 refers to the relative position and relative speed with the surrounding vehicle detected by the other vehicle detection unit 36. And if the distance between the vehicle 10 and the surrounding vehicle in the traveling direction of the vehicle 10 obtained from the relative position between the vehicle 10 and the surrounding vehicle is less than the distance threshold, the lane change control unit 37 decelerates based on the relative speed so that the speed of the vehicle 10 becomes lower than the speed of the surrounding vehicle. Also, if the distance between the vehicle 10 and the surrounding vehicle in the traveling direction of the vehicle 10 is equal to or greater than the distance threshold, the lane change control unit 37 may set the acceleration and deceleration based on the relative speed so that the speed of the vehicle 10 becomes the same as or lower than the speed of the surrounding vehicle.

[0102] The lane change control unit 37 sets the accelerator opening or the brake amount according to the set acceleration and deceleration. The lane change control unit 37 obtains the fuel injection amount according to the set accelerator opening and outputs a control signal corresponding to the fuel injection amount to the fuel injection device of the engine of the vehicle 10. Alternatively, the lane change control unit 37 obtains the amount of electric power supplied to the motor according to the set accelerator opening and controls the drive circuit of the motor so that the amount of electric power is supplied to the motor. Alternatively, the lane change control unit 37 outputs a control signal corresponding to the set brake amount to the brake of the vehicle 10.

[0103] When the vehicle 10 comes to completely travel in the adjacent lane, the lane change control unit 37 ends the lane change control. At this time, the lane change control unit 37 may determine whether the entire vehicle 10 is included in the adjacent lane by referring to the position of the vehicle 10 measured as described above and the high-precision map, or by referring to two lane dividing lines that divide the adjacent lane detected from the image. When the entire vehicle 10 is included in the adjacent lane, the lane change control unit 37 determines that the vehicle 10 has come to completely travel in the adjacent lane.

[0104] While the lane change control unit 37 is executing the lane change control, the determination unit 38 determines whether at least one of the relative position and the relative speed between the vehicle 10 and the surrounding vehicle traveling in the adjacent lane of the lane change destination detected by the other vehicle detection unit 36 satisfies a predetermined interruption condition.

[0105] For example, the determination unit 38 obtains the inter-vehicle distance between the host vehicle 10 and a surrounding vehicle traveling behind the host vehicle 10 in an adjacent lane based on the relative position between the surrounding vehicle and the host vehicle 10. When the inter-vehicle distance becomes less than a predetermined distance threshold, the determination unit 38 determines that the interruption condition is satisfied. Further, the determination unit 38 may predict the inter-vehicle distance between the surrounding vehicle and the host vehicle 10 up to a predetermined time in the future by applying prediction processing such as a Kalman filter to the change in the relative position between the surrounding vehicle and the host vehicle 10 in the most recent predetermined period. When the predicted inter-vehicle distance between the surrounding vehicle and the host vehicle 10 becomes less than the distance threshold at any point in time to be predicted, the determination unit 38 may determine that the interruption condition is satisfied. Note that the interruption condition may be set as a combination of the inter-vehicle distance and the relative speed between the surrounding vehicle and the host vehicle 10. For example, the distance threshold may be set to be smaller as the speed of the surrounding vehicle is faster than the speed of the host vehicle 10 and the relative speed between the surrounding vehicle and the host vehicle 10 is larger. Furthermore, when the speed of a surrounding vehicle traveling behind the host vehicle 10 in an adjacent lane is faster than the speed of the host vehicle 10 and the relative speed between the surrounding vehicle and the host vehicle 10 is larger than a predetermined speed threshold, the determination unit 38 may determine that the interruption condition is satisfied regardless of the inter-vehicle distance between the surrounding vehicle and the host vehicle 10. Further, the determination unit 38 may obtain the predicted time until the surrounding vehicle and the host vehicle 10 collide based on the prediction result of the inter-vehicle distance between the surrounding vehicle and the host vehicle 10. When the predicted time becomes less than or equal to a predetermined time threshold, the determination unit 38 may determine that the interruption condition is satisfied.

[0106] When there are a plurality of surrounding vehicles traveling behind the host vehicle 10 in the adjacent lane, the determination unit 38 may determine whether the interruption condition is satisfied by executing the above-described processing on the surrounding vehicle closest to the host vehicle 10.

[0107] Also, during the execution of the lane change control, the inter-vehicle distance between the vehicle 10 and its surrounding vehicles may suddenly decrease due to a sudden deceleration of a surrounding vehicle traveling ahead of the vehicle 10. Therefore, the determination unit 38 may determine whether the above interruption condition is satisfied for the surrounding vehicles traveling ahead of the vehicle 10 in the same manner as described above. However, regarding the condition related to the relative speed, unlike the condition for the subsequent surrounding vehicles, the determination unit 38 may determine that the interruption condition is satisfied when the relative speed of the surrounding vehicle with respect to the vehicle 10 is lower than a predetermined speed threshold. Also, the interruption condition for the surrounding vehicle traveling ahead of the vehicle 10 and the interruption condition for the surrounding vehicle traveling behind the vehicle 10 may be set separately.

[0108] In the present embodiment, the determination unit 38 relaxes the interruption condition when it is detected that the vehicle 10 is towing the towed vehicle 11 compared to the interruption condition when it is not detected that the vehicle 10 is towing the towed vehicle 11. For example, as described above, when the interruption condition is that the inter-vehicle distance between the vehicle 10 and the surrounding vehicle becomes shorter than the distance threshold, the determination unit 38 sets the distance threshold when it is detected that the vehicle 10 is towing the towed vehicle 11 to be larger than the distance threshold when it is not detected that the vehicle 10 is towing the towed vehicle 11. Also, when the interruption condition is that the relative speed of the surrounding vehicle with respect to the vehicle 10 becomes larger than the speed threshold, the determination unit 38 sets the speed threshold when it is detected that the vehicle 10 is towing the towed vehicle 11 to be smaller than the speed threshold when it is not detected that the vehicle 10 is towing the towed vehicle 11. Further, when the interruption condition is that the predicted time until the vehicle 10 and the surrounding vehicle collide becomes equal to or less than the time threshold, the determination unit 38 sets the time threshold when it is detected that the vehicle 10 is towing the towed vehicle 11 to be larger than the time threshold when it is not detected that the vehicle 10 is towing the towed vehicle 11.

[0109] FIG. 8 is a diagram showing the relationship between the presence or absence of detection of the towing of the towed vehicle 11 and a time threshold value which is an example of an interruption condition. In FIG. 8, the horizontal axis represents time, and the vertical axis represents the predicted time to collision (TTC) until the vehicle 10 collides with surrounding vehicles. And chart 800 represents the change in TTC over time. In this example, it is assumed that surrounding vehicles gradually approach the vehicle 10, and as a result, the TTC becomes shorter as time elapses.

[0110] As shown in FIG. 8, the time threshold value Thp when the towing of the towed vehicle 11 is detected is set to a value larger than the time threshold value Thn when the towing of the towed vehicle 11 is not detected. Therefore, the timing t1 at which the TTC becomes equal to or less than the time threshold value Thp is earlier than the timing t2 at which the TTC becomes equal to or less than the time threshold value Thn. Therefore, the lane change control is interrupted earlier when the towing of the towed vehicle 11 is detected than when it is not detected. Thus, the vehicle control device according to the present embodiment can interrupt the lane change control at a timing earlier by the amount of dullness of the behavior of the vehicle 10 due to the towing of the towed vehicle 11. Therefore, this vehicle control device can appropriately set the timing at which the lane change control is interrupted so as to reduce the possibility of contact between the surrounding vehicles and the vehicle 10 when the towed vehicle 11 is being towed.

[0111] When the determination unit 38 determines that the interruption condition is satisfied, it notifies the interruption instruction unit 39 of the determination result.

[0112] When the interruption instruction unit 39 receives the determination result from the determination unit 38 that the interruption condition is satisfied, it notifies the lane change control unit 37 of an instruction to interrupt the lane change control.

[0113] FIG. 9 is an operation flowchart of vehicle control processing according to the second embodiment. When the lane change determination unit 35 determines to apply lane change control, the processor 23 executes vehicle control processing related to lane change control according to the following operation flowchart.

[0114] The towing detection unit 31 of the processor 23 determines whether or not it has detected the towing of the towed vehicle 11 by the vehicle 10 (step S201).

[0115] If the towing of the towed vehicle 11 is not detected (step S201 - No), the determination unit 38 of the processor 23 sets the interruption condition relatively strictly (step S202). On the other hand, if the towing of the towed vehicle 11 is detected (step S201 - Yes), the determination unit 38 sets the interruption condition relatively loosely (step S203).

[0116] The determination unit 38 of the processor 23 determines whether or not the interruption condition has been satisfied while the lane change control unit 37 of the processor 23 is executing lane change control for the vehicle 10 (step S204). If the interruption condition is not satisfied (step S204 - No), the lane change control unit 37 determines whether or not the movement of the vehicle 10 to the adjacent lane of the change destination has been completed (step S205). If the movement of the vehicle 10 to the adjacent lane has been completed (step S205 - Yes), the processor 23 ends the vehicle control process related to the lane change control. On the other hand, if the movement of the vehicle 10 to the adjacent lane has not been completed (step S205 - No), the processor 23 repeats the processes after step S204.

[0117] In step S204, when the interruption condition is satisfied (step S204 - Yes), the lane change control unit 37 interrupts the lane change control and controls the vehicle 10 to continue traveling in its own lane (step S206). Thereafter, the processor 23 ends the vehicle control process related to the lane change control.

[0118] As described above, the vehicle control device according to the second embodiment relaxes the interruption condition of the lane change control when the towing of the towed vehicle is detected compared to the interruption condition of the lane change control when the towing of the towed vehicle is not detected. Therefore, this vehicle control device can interrupt the lane change control earlier by the amount of the sluggishness of the vehicle behavior due to towing, so that it is possible to appropriately set the timing of interrupting the lane change control so as to reduce the possibility of contact between the surrounding vehicles and the vehicle when towing the towed vehicle.

[0119] According to a modification example, similar to the modification example of the first embodiment, an interruption condition may be set for each situation around the vehicle 10. For example, separate interruption conditions may be set depending on whether the surrounding vehicle traveling in the adjacent lane of the destination is a large vehicle or other vehicles. However, even in this case, the determination unit 38 relaxes the interruption condition when it is detected that the vehicle 10 is towing the towed vehicle 11 compared to the interruption condition when it is not detected that the vehicle 10 is towing the towed vehicle 11, regardless of the type of the surrounding vehicle. Then, the determination unit 38 may determine whether to interrupt the lane change control based on the interruption condition corresponding to the vehicle type of the surrounding vehicle traveling in the adjacent lane of the destination detected by the other vehicle detection unit 36. When a plurality of surrounding vehicles traveling in the adjacent lane of the destination are detected, the determination unit 38 may use the interruption condition corresponding to the vehicle type of the surrounding vehicle closest to the vehicle 10.

[0120] Similarly, depending on the speed of the vehicle 10 at the time of executing the lane change control, the speed of the surrounding vehicles, the speed of the following vehicle following the vehicle 10, the lane width of the own lane or the adjacent lane, the type of the adjacent lane (overtaking lane, driving lane, etc.), the time zone or weather including the time of executing the lane change control, individual interruption conditions may be set. In this case, similar to the modification example of the first embodiment, by referring to the speed of the vehicle 10 measured by the vehicle speed sensor, the high-precision map or weather information, etc., the determination unit 38 may specify the interruption condition to be used. Further, depending on the event that triggered the lane change (lane change for overtaking the preceding vehicle, lane change for moving to the lane leading to the destination, etc.), individual interruption conditions may be set. In this case, the determination unit 38 may receive trigger information representing the event that triggered the lane change from the lane change determination unit 35 and select the interruption condition according to the trigger information. However, even in this case, the determination unit 38 relaxes the interruption condition when it is detected that the vehicle 10 is towing the towed vehicle 11 compared to the interruption condition when it is not detected that the vehicle 10 is towing the towed vehicle 11.

[0121] According to this modification example, the determination unit 38 can appropriately set the interruption condition according to not only the presence or absence of towing but also the situation around the vehicle 10.

[0122] Further, the processor 23 may be configured to execute both the vehicle control process according to the first embodiment or its modification example and the vehicle control process according to the second embodiment or its modification example. That is, the processor 23 may have each part shown in FIG. 3 and each part shown in FIG. 7.

[0123] A computer program for realizing the functions of the processor 23 of the ECU 9 according to the above embodiment or modification example may be provided in a form recorded on a computer-readable portable recording medium such as a semiconductor memory, a magnetic recording medium, or an optical recording medium.

[0124] As described above, those skilled in the art can make various changes according to the implemented forms within the scope of the present invention.

Explanation of Reference Numerals

[0125] 1 Vehicle control system 10 Vehicle 11 Towed vehicle 2 Camera 3 Driver monitoring camera 4 GPS receiver 5 Behavior sensor 6 Wireless communication terminal 7 Notification device 8 Storage device 9 Electronic control unit (ECU) 21 Communication interface 22 Memory 23 Processor 31 Towing detection unit 32 Control unit 33 Determination unit 34 Notification processing unit 35 Lane change determination unit 36 Other vehicle detection unit 37 Lane change control unit 38 Determination unit 39 Interrupt indication unit

Claims

[Claim 1] a towing detection unit that detects that a towed vehicle is being towed when the vehicle is under automatic driving control; a detection unit for detecting a relative position and a relative speed between the vehicle and another vehicle traveling in an adjacent lane adjacent to the lane in which the vehicle is traveling; a control unit that executes lane change control of the vehicle to change lanes from the own lane to the adjacent lane when a predetermined condition is satisfied; a determination unit that determines whether or not an interruption condition is satisfied based on at least one of a change in the relative position and the relative speed between the other vehicle and the vehicle during execution of the lane change control; an interruption instruction unit that causes the control unit to interrupt the lane change control when the interruption condition is satisfied; having the determination unit relaxes the interruption condition when it is detected that the vehicle is towing the towed vehicle, compared to the interruption condition when it is not detected that the vehicle is towing the towed vehicle. Vehicle control device.

Images