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

Abstract

To provide a vehicle control device capable of preventing the occurrence of a situation where a driver's visibility is not ensured, even if there arises a need to shift a control entity to the driver during automatic driving control of a vehicle.SOLUTION: A vehicle control device comprises: a situation determination unit 31 which determines whether a situation around a vehicle 1 during manual driving control is a situation where automatic driving control of the vehicle 1 can be started; and a transition determination unit 32 which, when the situation around the vehicle 1 is the situation where the automatic driving control can be started, shifts control of the vehicle 1 from the manual driving control to the automatic driving control, in a case where an operation mode of a device (16, 17, or 19) related to ensuring the visibility of a driver of the vehicle 1 is set to an automatic mode to automatically control the device, and which, on the other hand, continues the manual driving control as it is, in a case where the operation mode of the device (16, 17, or 19) related to ensuring the visibility of the driver is set to a manual mode to manually control the device and where the visibility of the driver is not ensured unless the device operates.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] In a vehicle to which autonomous driving control can be applied, the control entity of the vehicle may be transferred from an electronic control device mounted on the vehicle to the driver. In such a case, in order to enable the driver to appropriately take over the driving control of the vehicle, a technology for controlling in-vehicle devices has been proposed so as to ensure the driver's field of vision when the control entity is transferred (see, for example, Patent Documents 1 and 2).

[0003] The vehicle control device disclosed in Patent Document 1 activates an anti-fogging unit that prevents fogging of the vehicle windows when the driving control unit switches from automatic driving to manual driving. On the other hand, the vehicle control device controls a removal unit that removes dirt from the surrounding information detection unit when the driving control unit switches from manual driving to automatic driving.

[0004] Furthermore, a method for controlling driving state components of an autonomous vehicle disclosed in Patent Document 2 determines whether a current state will limit a driver's visibility and predicts whether the driver will enable a manual driving mode during the current state, and then controls the driving state components to alleviate the current state before the driver enables the manual mode. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-179767 [Patent Document 2] Japanese Patent Publication No. 2020-175884 Summary of the Invention [Problem to be solved by the invention]

[0006] In the above technology, while the vehicle is under automatic driving control, the control device automatically operates the in-vehicle devices so that the driver's visibility is ensured when control is transferred to the driver. However, the wiper operation mode may be set to a manual mode in which the driver manually controls the wipers, and the wipers may be stopped. In such a case, depending on the circumstances around the vehicle, even if it becomes difficult for the driver to maintain visibility while the vehicle is under automatic driving control, the control device may not be able to cause the in-vehicle devices to operate to maintain the driver's visibility.

[0007] Therefore, the present invention aims to provide a vehicle control device that can prevent a situation in which the driver's field of vision is not secured even when a situation arises in which control needs to be transferred to the driver while the vehicle is under automatic driving control. [Means for solving the problem]

[0008] According to one embodiment, there is provided a vehicle control device that includes a situation determination unit that determines whether a situation around a vehicle under manual driving control is such that automatic driving control of the vehicle can be started, and a transition determination unit that, when the situation around the vehicle is such that automatic driving control can be started, transitions vehicle control from manual driving control to automatic driving control if the operation mode of an apparatus related to ensuring the driver's field of view of the vehicle is set to an automatic mode that automatically controls the apparatus, and continues vehicle control under manual driving control if the operation mode of an apparatus related to ensuring the driver's field of view of the vehicle is set to a manual mode that manually controls the apparatus and the driver's field of view cannot be ensured unless the apparatus operates.

[0009] In this vehicle control device, the transition determination unit predicts the period during which automatic driving control can be applied when the control of the vehicle is transitioned from manual driving control to automatic driving control, and determines whether a situation will arise in which the driver's field of vision of the vehicle will not be secured when that period ends.If such a situation does not arise, it is preferable to transition the control of the vehicle from manual driving control to automatic driving control even if the operating mode of the equipment related to securing the driver's field of vision is set to manual mode when the vehicle situation is such that automatic driving control of the vehicle can be started.

[0010] In addition, if a situation arises in which the driver's visibility of the vehicle is not secured when the period in which automatic driving control can be applied ends, it is preferable for the transition determination unit to continue controlling the vehicle with manual driving control, even if the driver's visibility of the vehicle is secured when the conditions around the vehicle are such that automatic driving control of the vehicle can be started, if the operating mode of the equipment related to securing the driver's visibility is set to a manual mode in which the equipment is manually controlled, and if the driver's visibility cannot be secured unless the equipment operates.

[0011] In addition, in this vehicle control device, the device related to ensuring the driver's visibility is the wipers, and if the amount of rain measured by a rain sensor installed in the vehicle is above a predetermined threshold, or if the current position of the vehicle is included in a rainy area indicated by weather information received from another device, it is preferable that the transition determination unit determines that the driver's visibility will not be ensured unless the device operates.

[0012] Alternatively, if the device related to ensuring the driver's visibility is a headlight, and the illuminance measured by an illuminance sensor installed in the vehicle is below a predetermined threshold, or the current time is after sunset and before sunrise, it is preferable that the transition determination unit determines that the driver's visibility will not be ensured unless the device is operating.

[0013] Alternatively, if the equipment related to ensuring the driver's visibility is an air conditioning system and the humidity inside the vehicle's cabin measured by a humidity sensor installed in the vehicle is equal to or higher than a predetermined threshold, it is preferable that the transition determination unit determines that the driver's visibility will not be ensured unless the equipment is operating.

[0014] According to another embodiment, there is provided a vehicle control method including: determining whether a situation around a vehicle under manual driving control is such that automatic driving control of the vehicle can be started; and, if the situation around the vehicle is such that automatic driving control can be started, transitioning control of the vehicle from manual driving control to automatic driving control if an operation mode of an equipment related to ensuring the driver's visibility of the vehicle is set to an automatic mode that automatically controls the equipment; and, on the other hand, continuing control of the vehicle under manual driving control if the operation mode of an equipment related to ensuring the driver's visibility is set to a manual mode that manually controls the equipment and the driver's visibility cannot be ensured unless the equipment is operated.

[0015] According to yet another embodiment, there is provided a computer program for controlling a vehicle, the computer program including instructions for causing a processor mounted on the vehicle to execute the following: determine whether a situation around the vehicle under manual driving control is such that automatic driving control of the vehicle can be started; and, if the situation around the vehicle is such that automatic driving control can be started, transition control of the vehicle from manual driving control to automatic driving control if the operation mode of an equipment related to ensuring the driver's field of view of the vehicle is set to automatic mode in which the equipment is automatically controlled; and continue control of the vehicle under manual driving control if the operation mode of an equipment related to ensuring the driver's field of view is set to manual mode in which the equipment is manually controlled and the driver's field of view cannot be ensured unless the equipment is operated. [Effects of the Invention]

[0016] The vehicle control device of the present disclosure has the effect of preventing a situation in which the driver's field of vision is not secured, even if a situation arises in which control needs to be transferred to the driver while the vehicle is under automatic driving control. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic configuration diagram of a vehicle control system including a vehicle control device. [Figure 2] FIG. 2 is a hardware configuration diagram of an ECU, which is an example of a vehicle control device. [Figure 3] FIG. 2 is a functional block diagram of a processor of an ECU related to vehicle control processing. [Figure 4] 4 is an operational flowchart of a vehicle control process. [Figure 5] FIG. 10 is a diagram illustrating an example of transition determination according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0018] A vehicle control device, a vehicle control method, and a vehicle control computer program executed by the vehicle control device will be described below with reference to the drawings. The vehicle control device is capable of performing automatic driving control of a vehicle under predetermined circumstances. The vehicle control device determines whether the situation around the vehicle during manual driving control is a predetermined situation in which automatic driving control of the vehicle can be initiated. When the situation around the vehicle is the predetermined situation and the operation mode of an equipment related to ensuring the driver's visibility of the vehicle is set to an automatic mode that automatically controls the equipment, the vehicle control device transitions vehicle control from manual driving control to automatic driving control. On the other hand, when the operation mode of an equipment related to ensuring the driver's visibility is set to a manual mode that manually controls the equipment and the driver's visibility cannot be ensured unless the equipment operates, the vehicle control device continues to control the vehicle in manual driving control.

[0019] FIG. 1 is a schematic diagram of a vehicle control system including a vehicle control device. The vehicle control system 10 mounted on a vehicle 1 includes an external sensor 11, an illuminance sensor 12, a rainfall sensor 13, a notification device 14, and an electronic control unit (ECU) 15, which is an example of a vehicle control device. The external sensor 11, the illuminance sensor 12, the rainfall sensor 13, the notification device 14, and the ECU 15 are communicatively connected to each other via an in-vehicle network conforming to a communication standard such as a controller area network. Furthermore, the ECU 15 is connected via the in-vehicle network to an electronic control unit (BODY-ECU) 18 for controlling headlights 16 and wipers 17, and an air conditioning unit 19 for adjusting the temperature and humidity in the passenger compartment of the vehicle 1. The headlights 16, the wipers 17, and the air conditioning unit 19 are examples of devices related to ensuring the driver's visibility. Furthermore, the vehicle control system 10 may have a navigation device (not shown), a wireless communication device (not shown), and a receiver (not shown), such as a GPS receiver, that receives signals from a satellite positioning system to determine the position of the vehicle 1.

[0020] The exterior sensor 11 generates an exterior sensor signal representing the situation around the vehicle 1 at predetermined intervals. The exterior sensor 11 may be, for example, a camera installed inside the vehicle 1 to capture an image of a predetermined area outside the vehicle 1 (for example, the area in front of the vehicle 1). In this case, the exterior sensor signal is an image representing the predetermined area. Alternatively, the exterior sensor 11 may be a distance measurement sensor, such as a LiDAR or radar, that measures the distance to an object around the vehicle 1. In this case, the exterior sensor signal is a distance measurement signal representing the distance to an object in each direction within a predetermined distance measurement range. Note that the vehicle 1 may be provided with multiple exterior sensors 11 of the same type, such as multiple cameras or multiple distance measurement sensors. In this case, the exterior sensors 11 are installed so that their image capturing directions, image capturing ranges, or distance measurement ranges are different from one another. Alternatively, the vehicle 1 may be provided with multiple exterior sensors 11 of different types, such as cameras and distance measurement sensors.

[0021] Every time the vehicle exterior sensor 11 generates a vehicle exterior sensor signal, the vehicle exterior sensor 11 outputs the generated vehicle exterior signal to the ECU 15 via the in-vehicle network.

[0022] The illuminance sensor 12 is provided, for example, near the windshield inside the vehicle 1, and measures the brightness (illuminance) around the vehicle 1. The illuminance sensor 12 outputs an illuminance signal representing the measured brightness to the ECU 15 via the in-vehicle network at predetermined intervals.

[0023] The rainfall sensor 13 is provided, for example, on the windshield of the vehicle 1, and measures the amount of rainfall around the vehicle 1. The rainfall sensor 13 outputs a rainfall signal representing the measured amount of rainfall to the ECU 15 via the in-vehicle network at predetermined intervals.

[0024] The illuminance sensor 12 and the rainfall sensor 13 may be connected to the BODY-ECU 18. In this case, the ECU 15 may acquire the illuminance signal and the rainfall signal via the BODY-ECU 18.

[0025] The notification device 14 is provided in the passenger compartment of the vehicle 1 and provides a predetermined notification to the driver by light, sound, text display, or image display. To achieve this, the notification device 14 has, for example, at least one of a speaker, a light source, or a display device. When the notification device 14 receives a notification for the driver from the ECU 15, it notifies the driver of the notification by sound from the speaker, by emitting or flashing light from the light source, or by displaying a notification on the display device.

[0026] The ECU 15 is capable of performing automatic driving control of the vehicle 1 when the situation around the vehicle 1 is a predetermined situation. Therefore, when the vehicle 1 is being manually driven by the driver, the ECU 15 determines whether the situation around the vehicle 1 is a predetermined situation. When the situation around the vehicle 1 is a predetermined situation in which automatic driving control can be started, the ECU 15 determines whether the operation mode of the device related to ensuring the driver's field of view of the vehicle is set to automatic mode, and determines whether to transition to automatic driving control depending on the determination result.

[0027] Fig. 2 is a hardware configuration diagram of the ECU 15. As shown in Fig. 2, the ECU 15 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 integrated into a single integrated circuit.

[0028] The communication interface 21 has an interface circuit for connecting the ECU 15 to the in-vehicle network. Each time the communication interface 21 receives an external sensor signal from the external sensor 11, it passes the external sensor signal to the processor 23. Similarly, each time the communication interface 21 receives an illuminance signal from the illuminance sensor 12, it passes the illuminance signal to the processor 23. Each time the communication interface 21 receives a rainfall signal from the rainfall sensor 13, it passes the rainfall signal to the processor 23. When the communication interface 21 receives a signal indicating the operation mode of the headlights 16 or the wipers 17 from the BODY-ECU 18, it passes the signal to the processor 23. Furthermore, when the communication interface 21 receives a signal indicating the operation mode from the air conditioner 19, it passes the signal to the processor 23. Furthermore, when the communication interface 21 receives traffic information or weather information from another device (e.g., a traffic condition management server or a weather information reporting server) via a wireless communication device (not shown), it passes the traffic information or weather information to the processor 23. Furthermore, when the communication interface 21 receives a notification from the processor 23 to the driver, it outputs the notification to the notification device 14 .

[0029] The memory 22 is an example of a storage unit and includes, for example, a volatile semiconductor memory and a nonvolatile semiconductor memory. The memory 22 stores various algorithms and data used in the vehicle control process executed by the processor 23 of the ECU 15. For example, the memory 22 stores internal parameters indicating the installation position and measurement range of the external sensors 11, various parameters used to determine the vehicle's surroundings, and messages to notify the driver. The memory 22 may also store a high-precision map including information such as the position and shape of each road section within a predetermined area, road markings, road signs, and speed limits indicated on each road section. The high-precision map is used for autonomous driving control of the vehicle 1. The memory 22 also stores external sensor signals, illuminance signals, rainfall signals, traffic information, weather information, and operating modes currently applied to the headlights 16, windshield wipers 17, and air conditioner 19 received within a recent fixed period. The memory 22 also temporarily stores flags indicating the level of driving control currently applied to the vehicle 1 and various data generated during the vehicle control process. The vehicle exterior sensor signals, traffic information, and weather information are examples of situation information that indicates the situation around the vehicle 1.

[0030] The processor 23 includes one or more central processing units (CPUs) and their peripheral circuits. The processor 23 may further include other arithmetic circuits such as a logic unit, a numerical calculation unit, or a graphics processing unit. The processor 23 executes vehicle control processing.

[0031] 3 is a functional block diagram of the processor 23 related to vehicle control processing. The processor 23 has a situation determination unit 31, a transition determination unit 32, a notification unit 33, and a vehicle control unit 34. Each of these units included in the processor 23 is, for example, a functional module realized by a computer program running on the processor 23. Alternatively, each of these units included in the processor 23 may be a dedicated arithmetic circuit provided separately in the processor 23.

[0032] The situation determination unit 31 determines whether the vehicle 1 is under manual driving control by referring to a flag that indicates the level of driving control being applied to the vehicle 1. If the vehicle 1 is under manual driving control, the situation determination unit 31 determines whether the situation around the vehicle 1 is a predetermined situation in which automatic driving control of the vehicle 1 can be started.

[0033] In this embodiment, the predetermined situation in which automatic driving control of the vehicle 1 can be started is a situation in which there is traffic congestion around the vehicle 1. Therefore, the situation determination unit 31 determines whether there is traffic congestion around the vehicle 1 based on the situation information, and if there is traffic congestion around the vehicle 1, determines that automatic driving control of the vehicle 1 can be started.

[0034] For example, the situation determination unit 31 detects other vehicles traveling around the vehicle 1 based on a series of time-series external sensor signals obtained over a recent predetermined period and tracks the detected other vehicles. If the relative speed between the other vehicles and the vehicle 1 estimated based on the tracking results satisfies a predetermined congestion condition, the situation determination unit 31 determines that the area around the vehicle 1 is congested. In this case, the situation determination unit 31 detects other vehicles around the vehicle 1 by inputting the external sensor signals to a classifier that has been trained in advance to detect other vehicles traveling around the vehicle 1 from the external sensor signals. The situation determination unit 31 can use, as such a classifier, a so-called deep neural network (hereinafter simply referred to as DNN) with a convolutional neural network (hereinafter simply referred to as CNN) type architecture. Such a classifier is trained in advance using a learning method such as backpropagation using a large number of training images depicting other vehicles to be detected.

[0035] The situation determination unit 31 performs a predetermined tracking process, such as the KLT algorithm, on other vehicles detected from each of the time-series series of exterior sensor signals to associate areas in which the same other vehicle is represented (hereinafter referred to as object areas) in each exterior sensor signal. Furthermore, the situation determination unit 31 estimates the relative position of the other vehicle being tracked relative to the vehicle 1 at the time of acquiring each exterior sensor signal. Here, if the exterior sensor 11 includes a camera and the exterior sensor signal is an image acquired by the camera, the bottom edge of the object area in which the other vehicle is represented is estimated to represent the position where the road surface and the other vehicle meet. Therefore, the situation determination unit 31 can estimate the distance from the vehicle 1 to the other vehicle at the time of acquiring each image based on the orientation from the camera corresponding to the bottom edge of the object area in which the other vehicle is represented and the height of the camera from the road surface, which is one of the camera's internal parameters. Furthermore, the position of the object area in the image (e.g., the center of gravity of the object area) corresponds one-to-one with the direction of the other vehicle included in the object area as seen from the camera. Therefore, based on the position of the object region on each image, the situation determination unit 31 can estimate the relative orientation of the other vehicle being tracked relative to the vehicle 1. Then, based on the estimated distance and orientation to the other vehicle at the time each image is acquired, the situation determination unit 31 can estimate the relative position of the other vehicle being tracked relative to the vehicle 1.

[0036] Furthermore, if the external sensor 11 includes a distance measurement sensor and the external sensor signal is a distance measurement signal obtained by the distance measurement sensor, the direction corresponding to the center of gravity of the object region and the distance value at that direction in each distance measurement signal represent the direction and distance to the other vehicle relative to vehicle 1. Therefore, the situation determination unit 31 can estimate the relative position of the other vehicle being tracked relative to vehicle 1, based on the direction corresponding to the center of gravity of the object region in each distance measurement signal and the distance to the other vehicle at that direction.

[0037] The situation determination unit 31 selects a preceding vehicle traveling ahead of the vehicle 1 from among the other vehicles being tracked, based on the relative positions of the other vehicles being tracked with respect to the vehicle 1. If there are multiple preceding vehicles, the situation determination unit 31 may select the preceding vehicle that is closest to the vehicle 1 from among the multiple preceding vehicles. Then, based on the change in the relative position to the selected preceding vehicle within the most recent predetermined period (for example, 3 to 5 seconds), the situation determination unit 31 calculates the change in the relative speed and inter-vehicle distance between the vehicle 1 and the preceding vehicle within the most recent predetermined period.

[0038] The situation determination unit 31 determines that there is congestion around vehicle 1 if the absolute value of the relative speed between vehicle 1 and the preceding vehicle over the most recent predetermined period is less than or equal to a predetermined relative speed threshold (e.g., 1 m / s) and the inter-vehicle distance between vehicle 1 and the preceding vehicle is within a predetermined distance range (e.g., 3 m or more and 25 m or less).

[0039] Alternatively, the situation determination unit 31 may calculate a change in the relative speed between the vehicle 1 and the other vehicles for all other vehicles being tracked over a recent predetermined period. Then, the situation determination unit 31 may determine that there is congestion around the vehicle 1 when the relative speed of all other vehicles being tracked to the vehicle 1 over the recent predetermined period is equal to or less than a predetermined relative speed threshold (for example, 3 m / s).

[0040] Furthermore, the situation determination unit 31 may determine that the area around the vehicle 1 is congested if the speed of the vehicle 1 measured by a vehicle speed sensor (not shown) mounted on the vehicle 1 satisfies a predetermined congestion condition. For example, if the speed of the vehicle 1 measured by the vehicle speed sensor has been equal to or less than a predetermined congestion upper limit speed for a recent certain period of time, the situation determination unit 31 determines that the area around the vehicle 1 is congested. The congestion upper limit speed may be, for example, a value obtained by subtracting a predetermined offset value from the speed limit of the road on which the vehicle 1 is traveling. The situation determination unit 31 may identify the road on which the vehicle 1 is traveling and its speed limit by referring to a high-precision map stored in the memory 22 and the current position of the vehicle 1 measured by a GPS receiver (not shown).

[0041] Alternatively, if the current position of vehicle 1 determined by a GPS receiver (not shown) is included in a congested section indicated in traffic information received via a wireless communication device (not shown), the situation determination unit 31 may determine that there is congestion around vehicle 1.

[0042] Alternatively, the situation determination unit 31 may determine that the area around the vehicle 1 is congested only when it is determined that the area around the vehicle 1 is congested using any two or more of the above congestion determination methods.

[0043] When the situation determination unit 31 determines that there is a traffic jam around the vehicle 1, it notifies the transition determination unit 32 and the vehicle control unit 34 that automatic driving control for the vehicle 1 can be started.

[0044] Note that the predetermined situation in which autonomous driving control of the vehicle 1 can be started is not limited to the situation shown in the example above. For example, the predetermined situation in which autonomous driving control of the vehicle 1 can be started may be a situation in which the current position of the vehicle 1 is included in an area covered by a high-precision map and the road on which the vehicle 1 is traveling is a road of a predetermined standard (e.g., a highway for motor vehicles). In this case, when the vehicle 1 is under manual driving control, the situation determination unit 31 refers to the high-precision map and the current position of the vehicle 1 measured by a GPS receiver (not shown) at predetermined intervals. Then, when the current position of the vehicle 1 is included in an area covered by a high-precision map and the current position is on a road of a predetermined standard, the situation determination unit 31 may determine that autonomous driving control of the vehicle 1 can be started and notify the transition determination unit 32 and the vehicle control unit 34 of the determination result.

[0045] Furthermore, when autonomous driving control is being applied to the vehicle 1, the situation determination unit 31 determines whether predetermined conditions for starting the autonomous driving control are no longer satisfied. If the predetermined conditions are no longer satisfied, the situation determination unit 31 notifies the notification unit 33 and the vehicle control unit 34 that autonomous driving control cannot be continued. For example, if the conditions for determining that there is traffic congestion around the vehicle 1 are no longer satisfied, the situation determination unit 31 determines that the situation around the vehicle 1 has resolved. The situation determination unit 31 then notifies the notification unit 33 and the vehicle control unit 34 that autonomous driving control cannot be continued. Alternatively, if the distance from the current position of the vehicle 1 to a point outside the area covered by the high-precision map along the traveling direction of the vehicle 1 is less than a predetermined distance, the situation determination unit 31 notifies the notification unit 33 and the vehicle control unit 34 that autonomous driving control cannot be continued.

[0046] When the transition determination unit 32 is notified that the situation around the vehicle 1 is such that automatic driving control can be started for the vehicle 1, the transition determination unit 32 determines whether or not to transfer the subject of control of the vehicle 1 from the driver to the ECU 15, depending on the operation modes of devices related to ensuring the driver's visibility and the state of visibility of the driver. For example, the transition determination unit 32 determines whether or not to transfer the subject of control of the vehicle 1 from the driver to the ECU 15, depending on the operation modes of the headlights 16 and the wipers 17 and the state of visibility of the driver.

[0047] In this embodiment, when the operation modes of the headlights 16 and the wipers 17 are automatic modes, the transition determination unit 32 determines that the subject of control of the vehicle 1 is to be transferred from the driver to the ECU 15. The automatic mode for the headlights 16 is a mode in which the headlights 16 are automatically turned on or off based on an illuminance signal. The automatic mode for the wipers 17 is a mode in which the operation of the wipers 17 is automatically controlled based on a rainfall signal.

[0048] On the other hand, when at least one of the operation modes of the headlights 16 and the wipers 17 is set to a manual mode in which the devices are manually controlled, the transition determination unit 32 determines whether the driver's visibility will be ensured if the devices set to the manual mode do not operate. If the driver's visibility will not be ensured if the devices set to the manual mode do not operate, the transition determination unit 32 determines not to transfer the subject of control of the vehicle 1 to the ECU 15 and to continue the driving control of the vehicle 1 as manual driving control.

[0049] For example, if the illuminance around the vehicle 1 represented by the latest illuminance signal is equal to or lower than a predetermined illuminance threshold, the transition determination unit 32 determines that the surroundings of the vehicle 1 are so dark that the driver's visibility cannot be ensured unless the headlights 16 are turned on. Alternatively, the transition determination unit 32 determines whether the current time is within the period from sunset to sunrise based on the current time and date represented by a clock (not shown) installed in the vehicle 1 and the latitude and longitude of the vehicle's current location measured by a GPS receiver (not shown). If the current time is within the period from sunset to sunrise, the transition determination unit 32 may determine that the surroundings of the vehicle 1 are so dark that the driver's visibility cannot be ensured unless the headlights 16 are turned on. In such a case, even if the control entity of the vehicle 1 is transferred to the ECU 15 and autonomous driving control is initiated, there is a possibility that the surroundings of the vehicle 1 are too dark to ensure the driver's visibility when the autonomous driving control cannot be continued thereafter. Therefore, the transition determination unit 32 does not transfer the control entity of the vehicle 1 to the ECU 15.

[0050] Furthermore, if the amount of rainfall indicated by the latest rainfall signal is equal to or greater than a predetermined rainfall threshold, the transition determination unit 32 determines that the driver's visibility will be impaired unless the wipers 17 are operated. Alternatively, if the current location of the vehicle, as determined by a GPS receiver (not shown), is included in a rainy area indicated in weather information received via a wireless communication device (not shown), the transition determination unit 32 may determine that the driver's visibility will be impaired unless the wipers 17 are operated. In such a case, even if the control entity of the vehicle 1 is transferred to the ECU 15 and autonomous driving control is started, there is a possibility that the driver's visibility will be impaired due to rain if the autonomous driving control cannot be continued thereafter. Therefore, the transition determination unit 32 does not transfer the control entity of the vehicle 1 to the ECU 15.

[0051] Even if the operation mode of the headlights 16 is set to the manual mode, the surroundings of the vehicle 1 may be bright enough that the driver's visibility is ensured even when the headlights 16 are turned off, such as when the illuminance is higher than the illuminance threshold. In such a case, the transition determination unit 32 may transfer control of the vehicle 1 to the ECU 15. Similarly, even if the operation mode of the wipers 17 is set to the manual mode, if the driver's visibility is ensured even when the wipers 17 are not operating, such as when the rainfall is less than the rainfall threshold, the transition determination unit 32 may transfer control of the vehicle 1 to the ECU 15. Furthermore, even if the operation mode of the headlights 16 is set to the manual mode, if the headlights 16 are manually controlled to be turned on, the driver's visibility is ensured when the autonomous driving control is terminated, so the transition determination unit 32 may transfer control of the vehicle 1 to the ECU 15. Similarly, even if the operation mode of the wiper 17 is set to manual mode, if the wiper 17 is manually controlled to operate, the driver's visibility will be secured when the automatic driving control is terminated, so the transition determination unit 32 may transfer the control entity of the vehicle 1 to the ECU 15.

[0052] Furthermore, the transition determination unit 32 may refer to the operation mode of the air conditioner 19 to determine whether to transfer control of the vehicle 1 from the driver to the ECU 15. For example, when the humidity in the vehicle cabin measured by a humidity sensor (not shown) provided in the vehicle 1 is equal to or higher than the fogging determination threshold, the transition determination unit 32 determines that the driver's visibility will not be ensured unless the air conditioner 19 performs a defogging operation. In such a case, even if the control of the vehicle 1 is transferred to the ECU 15 and automatic driving control is started, if the automatic driving control cannot be continued thereafter, the windshield may fog up and the driver's visibility may not be ensured. Therefore, when the operation mode of the air conditioner 19 is set to the manual mode and the humidity in the vehicle cabin is equal to or higher than the fogging determination threshold, the transition determination unit 32 may determine not to transfer control of the vehicle 1 to the ECU 15 but to continue the driving control of the vehicle 1 in manual driving control. On the other hand, if the operation mode of the air conditioner 19 is set to the automatic mode, the transition determination unit 32 may transfer the control of the vehicle 1 to the ECU 15 even if the humidity in the vehicle compartment is equal to or higher than the fogging determination threshold.

[0053] The transition determination unit 32 notifies the notification unit 33 and the vehicle control unit 34 of the determination result as to whether or not to transfer the control subject of the vehicle 1 to the ECU 15. Furthermore, when the transition determination unit 32 determines that the driving control of the vehicle 1 should continue as manual driving control, it notifies the notification unit 33 of the reason for the determination.

[0054] When the notification unit 33 receives from the transition determination unit 32 a determination result that the control subject of the vehicle 1 will not be transferred to the ECU 15, the notification unit 33 outputs to the notification device 14 a notification (hereinafter referred to as a mode change notification) urging the driver to perform an operation to set the operation mode of the device that caused the determination to automatic mode. At this time, the notification unit 33 may include in the mode change notification a message indicating that the vehicle 1 can be controlled autonomously by setting the operation mode of the device in question to automatic mode. For example, if the control subject of the vehicle 1 is not transferred to the ECU 15 because the operation mode of the wiper 17 is set to manual mode, the notification unit 33 displays or outputs by voice a message on the notification device 14 saying, "Please set the operation mode of the wiper 17 to automatic mode. After setting to automatic mode, automatic driving of the vehicle 1 will start." In this way, the notification unit 33 can notify the driver that the automatic driving control of the vehicle 1 can be started by performing an operation to change the operation mode of the notified device.

[0055] On the other hand, when the notification unit 33 receives a judgment result from the transition judgment unit 32 that the control entity of the vehicle 1 will be transferred to the ECU 15, it outputs a notification to the notification device 14 to start automatic driving control of the vehicle 1, thereby notifying the driver that automatic driving control will be started.

[0056] Furthermore, when the notification unit 33 is notified by the situation determination unit 31 that the autonomous driving control cannot be continued, the notification unit 33 outputs a notification to the notification device 14 indicating that the autonomous driving control will be terminated and the control entity will be transferred to the driver. The notification that the autonomous driving control will be started and the notification that the autonomous driving control will be terminated are each an example of a control entity transfer notification.

[0057] When the vehicle control unit 34 is notified by the transition determination unit 32 that the control entity of the vehicle 1 will be transferred from the driver to the ECU 15, the vehicle control unit 34 performs autonomous driving control of the vehicle 1 from the notification onward. Furthermore, the vehicle control unit 34 rewrites the flag that indicates the level of driving control currently being applied to the vehicle 1, which is stored in the memory 22, to a value that indicates that autonomous driving control is currently being performed.

[0058] For example, the vehicle control unit 34 detects lane markings that define the lane in which the vehicle 1 is traveling (hereinafter referred to as the host lane) and objects (other vehicles, pedestrians, etc.) that exist around the vehicle 1 from the external sensor signals obtained by the external sensor 11. Then, based on the detected lane markings and moving objects, the vehicle control unit 34 sets a planned travel trajectory along which the vehicle 1 is scheduled to travel in a section from the current position of the vehicle 1 to a predetermined distance ahead. The planned travel trajectory is set, for example, as a set of target positions of the vehicle 1 at each point in time. For example, the vehicle control unit 34 sets the planned travel trajectory so that the vehicle 1 will travel along the host lane without colliding with objects in its surroundings. Then, the vehicle control unit 34 controls each unit of the vehicle 1 so that the vehicle 1 travels along the set planned travel trajectory.

[0059] In this case, the vehicle control unit 34 can detect objects and lane markings around the vehicle 1 by inputting the external sensor signals to a classifier that has been trained in advance to detect objects and lane markings around the vehicle 1 from the external sensor signals. As with the situation determination unit 31, the vehicle control unit 34 can use, for example, a DNN with a CNN-type architecture as such a classifier. Such a classifier is trained in advance according to a learning method such as backpropagation using a large number of training images that depict the objects or lane markings to be detected.

[0060] Furthermore, when the vehicle control unit 34 is notified by the situation determination unit 31 that the automatic driving control cannot be continued, the vehicle control unit 34 terminates the automatic driving control when a predetermined time (e.g., several tens of seconds) has elapsed since the notification. After the automatic driving control is terminated, the ECU 15 controls each part of the vehicle 1 in accordance with manual driving control by the driver. Furthermore, the vehicle control unit 34 rewrites a flag stored in the memory 22 that indicates the level of driving control being applied to the vehicle 1 to a value that indicates that manual driving control is being performed.

[0061] 4 is an operational flowchart of the vehicle control process executed by the processor 23. The processor 23 may execute the vehicle control process in accordance with the following operational flowchart at predetermined intervals while the vehicle 1 is being manually driven and controlled by the driver.

[0062] The situation determination unit 31 of the processor 23 determines whether or not the situation around the vehicle 1 is a predetermined situation that allows for starting automatic driving control of the vehicle 1 (step S101). If it is determined that the situation around the vehicle 1 is not a predetermined situation (step S101-No), the vehicle control unit 34 of the processor 23 continues manual driving control by the driver (step S102).

[0063] On the other hand, if it is determined that the situation around the vehicle 1 is a predetermined situation (step S101—Yes), the transition determination unit 32 of the processor 23 refers to the operation modes of devices related to ensuring the driver's visibility of the vehicle 1, such as the headlights 16 or the wipers 17. Then, the transition determination unit 32 determines whether the operation modes of those devices are set to manual mode (step S103). If the operation mode of the device is set to manual mode (step S103—Yes), the transition determination unit 32 determines whether the driver's visibility can be ensured without operating that device (step S104). If it is determined that the driver's visibility cannot be ensured without operating that device (step S104—No), the notification unit 33 of the processor 23 notifies the driver of a mode change notification related to that device via the notification device 14 (step S105). Then, the vehicle control unit 34 continues manual driving control by the driver (step S102).

[0064] On the other hand, in step S103, if the operation mode of the device related to ensuring the driver's field of view is set to the automatic mode (step S103-No), the transition determination unit 32 transfers the subject of control of the vehicle 1 from the driver to the ECU 15 (step S106). Also, if it is determined in step S104 that the driver's field of view can be ensured without operating the device (step S104-Yes), the transition determination unit 32 also transfers the subject of control of the vehicle 1 from the driver to the ECU 15 (step S106).

[0065] After step S106, the vehicle control unit 34 starts the automatic driving control of the vehicle 1 (step S107). After step S102 or step S107, the processor 23 ends the vehicle control process.

[0066] As described above, this vehicle control device determines whether the situation around the vehicle during manual driving control by the driver is a predetermined situation in which automatic driving control of the vehicle can be started. If the predetermined situation is met, and the operation mode of a device related to ensuring the driver's field of view of the vehicle is set to manual mode and the driver's field of view cannot be ensured unless the device operates, this vehicle control device continues to control the vehicle in manual driving control. Thus, this vehicle control device does not start automatic driving control if a situation arises in which control must be transferred to the driver after automatic driving control of the vehicle is started and there is a possibility that the driver's field of view will not be ensured at the time the situation arises. Therefore, this vehicle control device can prevent a situation in which the driver's field of view is not ensured even if a situation arises in which control must be transferred to the driver while the vehicle is under automatic driving control.

[0067] According to a modified example, the transition determination unit 32 may predict a period during which autonomous driving control is applicable when the driving control of the vehicle 1 is transitioned from manual driving control to autonomous driving control (referred to as an autonomous driving application period). The transition determination unit 32 may then determine whether a situation in which the driver's visibility is not ensured will occur when the autonomous driving application period ends. If the transition determination unit 32 determines that such a situation will not occur, the transition determination unit 32 transfers control of the vehicle 1 from the driver to the ECU 15, even if the situation around the vehicle 1 is a predetermined situation in which autonomous driving control can be started and the devices related to ensuring the driver's visibility are set to manual mode. Conversely, the transition determination unit 32 may predict that a situation in which the driver's visibility is not ensured will occur when the autonomous driving application period ends. In such a case, even if the driver's visibility is ensured when the situation around the vehicle 1 is determined to be a predetermined situation, the transition determination unit 32 may determine to continue manual driving control if the operation mode of the devices related to ensuring the driver's visibility is set to manual mode.

[0068] For example, as described above, if the predetermined situation in which autonomous driving control can be initiated is a situation in which there is congestion around vehicle 1, the transition determination unit 32 predicts the period from the current time until the situation around vehicle 1 is resolved as the autonomous driving application period. In this case, the transition determination unit 32 sets the predicted time until the congestion is resolved, which is included in traffic information received via a wireless communication device (not shown), as the autonomous driving application period. Alternatively, the transition determination unit 32 may set the period obtained by dividing the distance from the current position of vehicle 1 measured by a GPS receiver (not shown) to the head point of the congestion, which is included in the traffic information, by the average speed of vehicle 1 over the most recent predetermined period, as the autonomous driving application period.

[0069] Furthermore, the predetermined situation in which autonomous driving control can be initiated is a situation in which the current position of vehicle 1 is included in an area covered by a high-precision map, and the road on which vehicle 1 is traveling is a road of a predetermined standard. In such a case, the transition determination unit 32 determines the predicted time until vehicle 1 reaches outside the area covered by the high-precision map as the autonomous driving application period. In this case, the transition determination unit 32 calculates the distance from the current position of vehicle 1 to the outer edge of the area covered by the high-precision map along the planned travel route set by a navigation device (not shown). The transition determination unit 32 then divides this distance by the average speed of vehicle 1 over the most recent predetermined period to predict the autonomous driving application period.

[0070] The transition determination unit 32 determines whether a situation in which the driver's visibility will be impaired will occur when the predicted autonomous driving application period ends. For example, if the time when the autonomous driving application period has elapsed from the current time is after sunset and before sunrise, the transition determination unit 32 determines that a situation in which the driver's visibility will be impaired will occur. If the autonomous driving application period ends after sunset and before sunrise, the transition determination unit 32 determines that manual driving control will continue if the headlights 16 are set to manual mode and are turned off. Conversely, if the autonomous driving application period ends before sunset, the transition determination unit 32 may transfer control of the vehicle 1 from the driver to the ECU 15 even if the headlights 16 are set to manual mode. Similarly, if the predicted location of the vehicle 1 when the autonomous driving application period ends is inside a tunnel, the transition determination unit 32 determines that a situation in which the driver's visibility will be impaired will occur when the autonomous driving application period ends. Therefore, in this case as well, if the headlights 16 are set to manual mode and are turned off, the transition determination unit 32 may determine to continue manual driving control. Note that the transition determination unit 32 may set, as the predicted position of the vehicle 1 during the autonomous driving application period, a position forward from the current position of the vehicle 1 along the planned driving route of the vehicle 1 by a predicted traveling distance obtained by multiplying the average speed of the vehicle 1 over the most recent predetermined period by the length of the autonomous driving application period, for example.

[0071] Alternatively, if the weather around vehicle 1 is predicted to be rainy when the autonomous driving application period has elapsed from the current time, transition determination unit 32 may determine that a situation will arise in which the driver's visibility will be impaired. More specifically, transition determination unit 32 may determine that a situation will arise in which the driver's visibility will be impaired when the predicted position of vehicle 1 when the autonomous driving application period has elapsed is included in an area where it will be rainy, which is indicated in weather information received via a wireless communication device (not shown).

[0072] In this case, if the wipers 17 are set to the manual mode and are set to stop operating, the transition determination unit 32 determines to continue manual driving control. Conversely, if the weather around the vehicle 1 is not predicted to be rainy when the autonomous driving application period ends, the transition determination unit 32 may transfer the subject of control of the vehicle 1 from the driver to the ECU 15 even if the wipers 17 are set to the manual mode.

[0073] Figure 5 is a diagram showing an example of transition determination by transition determination unit 32 according to this modified example. In Figure 5, the horizontal axis represents time. Also, assume that at time t1, the situation around vehicle 1 is determined to be a predetermined situation in which autonomous driving control can be started. Furthermore, assume that the period P from time t1 to time t2 is the autonomous driving application period.

[0074] 5, it is determined that a situation will not occur in which the driver's visibility will not be ensured at time t2, when it is predicted that the autonomous driving application period P will end. Therefore, the transition determination unit 32 determines that the driving control of the vehicle 1 will be transitioned from manual driving control to autonomous driving control, regardless of the operation modes of the headlights 16, wipers 17, etc.

[0075] 5, it is determined that the driver's visibility will not be ensured at time t2, when the autonomous driving application period P is predicted to end. Therefore, even if the driver's visibility is ensured at time t1, the transition determination unit 32 determines whether or not to transition the driving control of the vehicle 1 from manual driving control to autonomous driving control, depending on the operation modes of the headlights 16, wipers 17, etc.

[0076] According to this modified example, the transition determination unit 32 can more appropriately determine whether to start automatic driving control or continue manual driving control when a specified situation occurs, thereby further improving convenience for the driver.

[0077] In addition, a computer program that realizes the functions of the processor 23 of the ECU 5 according to the above embodiment or variant 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.

[0078] As described above, those skilled in the art can make various modifications to the embodiments within the scope of the present invention. [Explanation of symbols]

[0079] 1 vehicle 10 Vehicle Control System 11. Outside vehicle sensor 12 Illuminance sensor 13 Rainfall sensor 14 Notification device 15 Electronic Control Unit (ECU) 16 Headlight 17. Wiper 18 BODY-ECU 19 Air conditioner 21 Communication Interface 22 Memory 23 processors 31 Situation Judgment Section 32 Transition judgment section 33 Notification Department 34 Vehicle control unit

Claims

1. a situation determination unit that determines whether a situation around a vehicle under manual driving control is a situation in which automatic driving control of the vehicle can be started; a transition determination unit that, when the situation around the vehicle is such that automatic driving control can be started, transitions the control of the vehicle from manual driving control to automatic driving control if the operation mode of an equipment related to ensuring the driver's field of view of the vehicle is set to an automatic mode that automatically controls the equipment, and, on the other hand, continues the control of the vehicle as manual driving control if the operation mode of the equipment is set to a manual mode that manually controls the equipment and the driver's field of view cannot be ensured unless the equipment operates; A vehicle control device having the above.

2. 2. The vehicle control device according to claim 1, wherein the transition determination unit predicts a period during which automatic driving control can be applied when control of the vehicle is transitioned from manual driving control to automatic driving control, determines whether a situation will occur in which the driver of the vehicle's visibility will not be secured when the period ends, and if such a situation does not occur, transitions control of the vehicle from manual driving control to automatic driving control even if the operating mode of the equipment is set to manual mode when the situation around the vehicle is such that automatic driving control of the vehicle can be started.

3. 3. The vehicle control device of claim 2, wherein, when a situation arises in which the visibility of the driver of the vehicle is not ensured when the period in which the automatic driving control can be applied ends, the transition determination unit continues to control the vehicle under manual driving control even if the visibility of the driver of the vehicle is ensured when the situation around the vehicle is such that automatic driving control of the vehicle can be started, if the operating mode of the device is set to a manual mode in which the device is manually controlled, and if the visibility of the driver is not ensured unless the device operates.

4. A vehicle control device as described in any one of claims 1 to 3, wherein the device is a windshield wiper, and if the amount of rain measured by a rain sensor installed in the vehicle is equal to or greater than a predetermined threshold, or if the current location of the vehicle is included in a rainy area indicated in weather information received from another device, the transition determination unit determines that the driver's visibility will not be secured unless the device operates.

5. The vehicle control device according to any one of claims 1 to 3, wherein the device is a headlight, and if the illuminance measured by an illuminance sensor provided in the vehicle is below a predetermined threshold, or if the current time is after sunset and before sunrise, the transition determination unit determines that the driver's visibility will not be ensured unless the device is operated.

6. The vehicle control device according to any one of claims 1 to 3, wherein the device is an air conditioning device, and when the humidity inside the vehicle's cabin measured by a humidity sensor installed in the vehicle is equal to or higher than a predetermined threshold, the transition determination unit determines that the driver's visibility will not be ensured unless the device operates.

7. Determine whether the situation around the vehicle during manual driving control is such that automatic driving control of the vehicle can be started; When the situation of the vehicle is such that automatic driving control can be started, and the operation mode of the device related to ensuring the driver's visibility of the vehicle is set to an automatic mode that automatically controls the device, the control of the vehicle is transitioned from manual driving control to automatic driving control, If the operation mode of the device is set to a manual mode in which the device is manually controlled, and if the driver's visibility cannot be ensured unless the device operates, continue to control the vehicle in manual driving control. A vehicle control method comprising:

8. Determine whether the situation around the vehicle during manual driving control is such that automatic driving control of the vehicle can be started; When the situation of the vehicle is such that automatic driving control can be started, and the operation mode of the device related to ensuring the driver's visibility of the vehicle is set to an automatic mode that automatically controls the device, the control of the vehicle is transitioned from manual driving control to automatic driving control, If the operation mode of the device is set to a manual mode in which the device is manually controlled, and if the driver's visibility cannot be ensured unless the device operates, continue to control the vehicle in manual driving control. A computer program for vehicle control that causes a processor mounted on the vehicle to execute the above.

Images