Vehicle driving control method and driving control device

Abstract

A processor 10 references a switchover condition C in which vehicle speed and input form information of an input command are correlated in advance, determines whether or not an input form of the input command satisfies the switchover condition C in accordance with the vehicle speed, and in a case of determining that the input form of the input command satisfies the switchover condition C in accordance with the vehicle speed, switches a control mode of a vehicle from autonomous driving control over to manual driving control, and causes driving of the vehicle to be executed by manual driving control, on the basis of the input command.

Description

[Technical field]

[0001] The present invention relates to a vehicle driving control method and a driving control device capable of executing autonomous driving control and manual driving control. [Background technology]

[0002] A technology is known that determines whether a steering intervention operation performed during autonomous driving is an override command based on the driver's intention or an erroneous operation, based on a steering transition pattern obtained via a steering wheel touch sensor at low speeds (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-214241 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, while the above-described conventional technology can determine whether an operation at low speeds is an erroneous operation, it cannot determine the driver's intention with respect to operations at speeds other than low speeds.

[0005] The problem that the present invention aims to solve is to provide a driving control method and a driving control device that appropriately determine the intention of the driver's input operation requesting switching from autonomous driving control to manual driving control according to the vehicle speed. [Means for solving the problem]

[0006] The present invention solves the above problem by determining the input mode of an input command, referring to switching conditions that are pre-matched between vehicle speed and input mode information of the input command, and if the input mode of the input command satisfies the switching condition pre-matched with the vehicle speed, switching the vehicle's control mode from autonomous driving control to manual driving control and executing vehicle driving. Effect of the Invention

[0007] According to the present invention, the intention of the driver who inputs an input command is determined according to the speed based on switching conditions according to the vehicle speed, thereby improving the accuracy when handing over the initiative in driving control to the driver. [Brief description of the drawings]

[0008] [Figure 1] 1 is a block diagram showing an embodiment of an operation control device; [Diagram 2] FIG. 2 illustrates an example of an input device. [Diagram 3] FIG. 13 is a diagram illustrating an example of a combination of input devices. [Figure 4] FIG. 13 is a diagram showing an example of a switching condition C. [Diagram 5] 11 is a diagram showing an example of a switching condition in which a vehicle speed is associated with an evaluation threshold value related to the number of operations of an input system; FIG. [Figure 6] FIG. 11 is a diagram showing an example of a switching condition in which a vehicle speed is associated with a torque threshold value; [Figure 7] FIG. 13 is a diagram illustrating an example of correction of a switching condition. [Figure 8] 4 is a flowchart showing an example of a control procedure of an operation control process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] FIG. 1 is a block diagram showing a configuration of a driving control system 100 including a vehicle driving control device 1 according to this embodiment. As shown in FIG. 1, the vehicle driving control system 100 according to this embodiment includes a driving control device 1, a sensor 11, a vehicle position detection device 12, a map database 13, an in-vehicle device 14, an input device 15, a presentation device 16, and a drive control device 17. The driving control device 1 includes a processor 10 and a communication device 20. These devices are connected to each other by, for example, a controller area network (CAN) or other in-vehicle LAN in order to transmit and receive information to and from each other. The vehicle driving control device 1 according to this embodiment is one form of a device that implements a vehicle driving control method according to the present invention.

[0010] The sensor 11 detects the running state of the host vehicle used for driving control of the vehicle. Examples of the sensor 11 include one or more cameras that capture images of the front, side, and rear of the host vehicle, one or more radars, laser scanners, and ultrasonic sonars that detect obstacles in front, side, and rear of the host vehicle, a vehicle speed sensor that detects the vehicle speed of the host vehicle, a sensor that detects the rotation direction of the steering wheel, a sensor that detects the steering torque (input torque) applied to the steering wheel, a sensor that detects the accelerator or brake pedal depression torque (input torque) of the host vehicle, a touch sensor (capacitive sensor) that detects whether the driver is holding the steering wheel, a touch sensor that detects that the driver has touched a touch switch arranged on a touch panel display screen, and an in-vehicle camera that captures the driver and his / her actions. One of the above-mentioned multiple sensors 11 or a combination of two or more types of sensors 11 may be used. The detection result of the sensor 11 is output to the processor 10 at a predetermined period.

[0011] The vehicle position detection device 12 is composed of a GPS unit, a gyro sensor, a vehicle speed sensor, etc. The vehicle position detection device 12 detects radio waves transmitted from multiple satellite communications by the GPS unit, periodically acquires position information of the vehicle that is the subject of driving control, and detects the current position of the vehicle based on the acquired vehicle position information, angle change information acquired from the gyro sensor, and vehicle speed acquired from the vehicle speed sensor. The vehicle position information detected by the vehicle position detection device 12 is output to the processor 10 at a predetermined cycle.

[0012] The map database 13 readably stores map information such as high-precision map information including position information of various facilities and specific points. The high-precision map information includes lane identification information, and is information in which "static information" such as the road shape for each lane (for example, curvature or curvature radius), lane or road attributes (lane width, whether it is a vehicle-only road, speed limit), lane merging points, branching points, positions where the number of lanes is reduced, positions and contents of signs, positions of road structures such as road shoulders, positions of facilities such as toll booths, etc., and "dynamic information" such as congestion information for each lane and current or future weather in the area including the lane are associated with the lane identification information.

[0013] The in-vehicle devices 14 are various devices mounted on the vehicle and are operated by the driver. Such in-vehicle devices 14 include a steering wheel, an accelerator pedal, a brake pedal, a navigation device, a turn signal, wipers, lights, and a horn. When the in-vehicle devices 14 are operated by the driver, the information is output to the processor 10.

[0014] The input device 15 includes a plurality of input devices 15 (first input device 15-1, second input device 15-2, N-th input device 15-N: N≠1). The input device 15 accepts an input operation by the driver to the in-vehicle device 14. The input device 15 is, for example, a button switch that can be input by the driver's operation, a touch switch arranged on a touch panel display screen, a switch that can be input by steering operation, a switch that can be input by depressing the brake, or a microphone that can be input by the driver's voice. Note that an accelerator pedal of a drive mechanism 171 that controls the drive of the vehicle, a brake pedal of a braking mechanism 172, or a steering wheel of a steering mechanism 173 that controls the traveling direction of the vehicle functions as the input device 15. An input torque input via a steering operation of the steering wheel, or an input torque input via depressing the brake pedal or accelerator pedal is output to the processor 10.

[0015] FIG. 2 is a diagram showing an example of the input device 15 of the present embodiment. The input device 15 includes a button switch group 15A arranged on the spokes of the steering wheel, a steering switch 15B that allows input of an input command by rotating the steering wheel, a touch switch 15C provided on the display surface of a display as the presentation device 16, and a switch group 15D provided at a position different from the button switch group 15A. The switch group 15D can be provided on the spokes of the steering wheel, the center console, or the instrument panel. The switch may be a microphone that accepts voice input. An example of the button switch group 15A of the input device 15 shown in the figure is a button-type switch used to set ON / OFF of an autonomous speed control function and an autonomous steering control function, which are the control modes of the autonomous driving provided in the processor 10, and includes a main switch 151, a resume / accelerate switch 152, a set / coast switch 153, a cancel button 154 that releases the autonomous driving control, a vehicle distance adjustment switch 155, and a lane change support switch 156. 2, the brake pedal, turn signals, lights, and other switches of the in-vehicle equipment 14 can be used as the input device 15. A specific switch among the input devices 15 may function as a confirmation switch that is operated to confirm the driver's intention. The input device 15 sends to the processor 10 information on the type of input system that has accepted the input command (identification information of the input device 15-N) and information on the input mode including the input torque to the input device 15(N).

[0016] Each switch can be used for input operation in combination with one or more other switches. FIG. 3 is a diagram showing an example of a combination of the first input device 15-1 and the N-th input device 15-N. Each input device 15 and its combination can be defined arbitrarily. When a combination C12 of the cancel button 154 and the confirmation switch of the switch group 15D is detected, the type of the input system is the "cancel button 154" and the "confirmation switch", and the number of operations is 2. In this example, when an input is made via a common input device 15, the number of operations of the input system is not counted up. Therefore, when C12 and C13 are detected, the number of operations of the input system is 3. On the other hand, it is also possible to assign different identification information to the first input and the second input to the same input device 15, and count up the number of multiple input operations as the number of operations.

[0017] The presentation device 16 is a device for conveying information to a passenger, and is, for example, an information presentation device such as a display provided in a navigation device, a display built into a rearview mirror, a display built into a meter section, a head-up display projected on a windshield, a speaker provided in an audio device, and a seat device with an embedded vibrator. Under the control of the processor 10, the presentation device 16 notifies the driver of the acceptance or rejection of a switching command and the switching of the control mode.

[0018] The drive control device 17 controls the driving of the host vehicle according to instructions from the processor 10, which will be described later. The drive control device 17 has an autonomous speed control function that drives the host vehicle at a constant speed at a set speed, and an autonomous following drive control function that drives the host vehicle to follow the preceding vehicle. To achieve these functions, the drive control device 17 controls the operation of the drive mechanism 171 and the operation of the braking mechanism to achieve the acceleration / deceleration and running speed of the host vehicle. Furthermore, the drive control device 17 has a lane keeping driving function that detects lane markers of the lane in which the host vehicle is running, and controls the running position of the host vehicle in the width direction so that the host vehicle runs within the lane, and a driving support function that causes the host vehicle to autonomously overtake the preceding vehicle, change lanes, and turn right or left at an intersection. To achieve these functions, the drive control device 17 performs steering control of the host vehicle by controlling the operation of the steering actuator of the steering mechanism 173, in addition to the operation of the drive mechanism 171 and the braking mechanism 172 to achieve the acceleration / deceleration and running speed. The method of driving control by the drive control device 17 (method of autonomous driving control and manual driving control) is not particularly limited, and the technology at the time of filing of this application can be applied.

[0019] The processor 10 of the driving control device 1 controls the driving of the vehicle in an autonomous driving control mode A executed by the autonomous driving system and a manual driving control mode B executed by an operation input by the driver, and also controls switching between these control modes. The control mode switching from autonomous driving control to manual driving control is also called takeover processing. The processor 10 is composed of a ROM (Read Only Memory) that stores a program for controlling the driving of the vehicle, a CPU (Central Processing Unit) that executes the program stored in the ROM, and a RAM (Random Access Memory) that functions as an accessible storage device. The processor 10 transmits and receives information via a communication device 20.

[0020] The processor 10 executes a program stored in the ROM by the CPU, thereby realizing an autonomous driving control function for autonomously controlling the traveling of the vehicle, an input mode judgment function for judging the input mode of an input command input by an input operation of the driver, a condition judgment function for judging whether the input mode of the input command satisfies a switching condition associated with the vehicle speed, and a switching function for switching the control mode of the vehicle from autonomous driving control to manual driving control. Furthermore, the processor 10 may be provided with a correction function for correcting the switching condition and / or an input judgment function for judging whether an input operation has been input. Each function will be described below.

[0021] First, the input mode determination function will be described. The processor 10 determines the input mode of the input command input by the driver's input operation. The input mode includes one or more of the following, or a combination of a plurality of the following: the type of the input system to which the input command is input, the number of operations of the input system, and the input torque of the input operation of the input command.

[0022] The processor 10 extracts the identification information of the input device 15 indicating the input system from the information of the multiple input commands, and determines the type of the input system. The processor 10 compares the extracted identification information of the input device 15, and counts the number of input devices 15 that the driver has operated to input based on the number of non-identical pieces of identification information, thereby determining the number of operations of the input system.

[0023] The processor 10 acquires the input torque (amount) of the input operation when the user inputs an input command based on detection information obtained from sensors of each mechanism that controls the driving of the vehicle. The input torque is the amount of steering of the steering wheel or the amount of depression of the brake pedal. The steering torque of the driver applied to the steering wheel is detected by a torque sensor of the steering mechanism 173. The brake depression torque applied to the brake pedal is detected by a torque sensor of the braking mechanism 172.

[0024] The condition determination function will be described. The processor 10 determines whether or not the input mode of the input command satisfies a switching condition associated with the vehicle speed. FIG. 4 shows an example of the switching condition C. The switching condition C is stored in a storage device such as a ROM. This switching condition C is a condition in which the vehicle speed (including the vehicle speed range) and the input mode information of the input command are associated in advance. The input mode information in this example includes the type of the input system, an evaluation threshold value for the number of operations of the input system, the order of input operations of the input system, and an input torque threshold value.

[0025] The switching condition C shown in FIG. 4 defines four vehicle speed ranges, a first vehicle speed range VR1 to a fourth vehicle speed range VR4. The switching condition C defines one or more "types of input systems" for the input command required to execute the control mode switching command for each vehicle speed range. For example, the first vehicle speed range VR1 defined as the highest vehicle speed range (VX1≧V2) is associated with four types of input systems: (1) main switch 151, (2) cancel button 154, (3) touch switch 15C, and (4) brake pedal operation. The switching condition C may define the order of operation of the switches to be operated. The input operation may be required according to the above numbered order (1) to (4). The switching condition C requests an input operation via the input systems (1) to (4) to execute the control mode switching process when the vehicle is traveling at a speed within the range of the first vehicle speed range VR1. In this switching condition C, the number of types of input systems associated with a relatively high first vehicle speed range VR1 (e.g., V2 or higher) is greater than the number of types of input systems associated with a second vehicle speed range VR2 (e.g., less than V2) that is lower than the first vehicle speed range VR1. At a relatively high vehicle speed, a high input load is imposed to confirm the driver's intention. By requesting the driver to input via more types of input systems, the driver's intention is accurately determined.

[0026] Moreover, the switching condition C shown in FIG. 4 defines an "evaluation threshold value AT for the number of operations of the input system" for the input command required to execute the control mode switching command for each vehicle speed range. In this switching condition C, the first evaluation threshold value AT1 for the number of operations of the input system associated with a relatively high first vehicle speed range VR1 (for example, V2 or higher) is a higher (larger) value than the second evaluation threshold value AT2 for the number of operations of the input system associated with a second vehicle speed range VR2 (for example, less than V2) lower than the first vehicle speed range VR1. FIG. 5 shows the relationship between the vehicle speed V and the evaluation threshold value AT for the number of operations of the input system. The evaluation threshold value AT associated with a high vehicle speed is a higher value than the evaluation threshold value AT' associated with a relatively low vehicle speed, and the higher the vehicle speed, the greater the number of operations of the input system required to execute the control mode switching command. At a relatively high vehicle speed, a high input load is imposed to confirm the driver's intention. By requesting the driver to perform more operations, the driver's intention is accurately determined. The evaluation threshold may be set so that the evaluation threshold increases stepwise as the vehicle speed range increases, as shown by the solid line in FIG. 5, or so that the evaluation threshold increases as the vehicle speed increases, as shown by the dashed line in the same figure. The evaluation threshold is experimentally set based on vehicle performance, etc. Although not particularly limited, the lower limit vehicle speed V1, which is the threshold of the second vehicle speed range VR2, may be set to 20-50 km / h, preferably 30-40 km / h. V0 in the fourth vehicle speed range VR4, which is an extremely low speed range where the vehicle can be stopped even by a sudden brake operation, may be set to 5-10 km / h. In the fourth vehicle speed range VR4 in this example, the type of the input system is set to only the brake pedal, and the evaluation threshold for the number of operations is set to "1".

[0027] As shown in Fig. 4, switching condition C defines the torque threshold of the input torque according to the vehicle speed as input mode information. The torque threshold defines the torque threshold that is the criterion for judging whether or not an input command has been executed when an input operation is performed to control the driving, braking, and steering of the vehicle. Switching condition C defines a torque threshold for each input operation that controls the driving, braking, and steering of the vehicle for each vehicle speed range. The torque threshold is defined based on the amount of depression of the brake pedal, the amount of depression of the accelerator pedal, and the amount of steering of the steering wheel.

[0028] In this switching condition C, the first torque threshold TT1 for the depression amount of the brake pedal associated with a relatively high first vehicle speed range VR1 (for example, V2 or more) is a value lower than the torque threshold TT2 associated with a second vehicle speed range VR2 (for example, less than V2) lower than the first vehicle speed range VR1. FIG. 6 shows the relationship between the vehicle speed V and the torque threshold TT of the input torque. As shown in the figure, the input torque threshold TT associated with a high vehicle speed is a value lower than the input torque threshold TT' associated with a relatively low vehicle speed, and the higher the vehicle speed, the lower the torque amount in the input operation required to execute the control mode switching command. The torque threshold may be set so that the torque threshold becomes gradually lower as the vehicle speed range becomes higher, as shown by the solid line in FIG. 6, or may be set so that the torque threshold becomes lower as the vehicle speed becomes higher, as shown by the dashed line in the figure. The torque threshold is experimentally set based on the vehicle performance and the like.

[0029] Here, the input determination function will be described. The processor 10 determines whether or not an input operation has been input. The processor 10 refers to the torque threshold value TT defined in the switching condition C in association with the vehicle speed. When the input torque is equal to or greater than the torque threshold value TT corresponding to the vehicle speed, the processor 10 determines that an input command has been "input". When it is determined that an input command has been input, the above-mentioned input mode determination function is used to obtain the type of the input command or the number of operations as the input mode. The processor 10 determines whether or not the switching condition C corresponding to the vehicle speed is satisfied based on the input mode. By setting a torque threshold value corresponding to the vehicle speed for each input operation and determining that an input operation has been performed when the torque threshold value is equal to or greater than the vehicle speed, it is possible to accurately determine whether or not an input command has been input, and to determine the driver's intention with high accuracy. In addition, since the vehicle behavior amount according to the input torque amount increases when the vehicle speed is high, this switching condition C does not require a large input torque for switching control when the vehicle speed is high. Therefore, while ensuring the stability of driving, it is possible to accurately determine whether an input command has been input, and the driver's intention can be determined with high accuracy. On the other hand, the input torque for moving the vehicle by a predetermined amount increases as the vehicle speed decreases. Therefore, even if the torque threshold is set high in the extremely low speed range as in the fourth vehicle speed range VR4 of FIG. 4, the driver's operational load is not increased by the switching condition C. In the extremely low speed range, the vehicle behavior amount does not change significantly even if a large input torque amount is input, so by requesting a relatively large input torque, the driver's intention can be accurately confirmed and the driver can reliably take over the initiative in driving control.

[0030] Next, the condition determination function will be described. The processor 10 determines whether or not the input mode of the input command satisfies the switching condition associated with the vehicle speed. The processor 10 refers to the switching condition C and extracts the threshold value (predetermined type of input system / evaluation threshold value of the number of operations / torque threshold value) of the input mode information to which the vehicle speed VX detected at the input timing of the input command belongs. The switching condition C according to the vehicle speed is a value for evaluating whether or not the input command input at that vehicle speed is based on the driver's intention. When the input mode information acquired by the input command satisfies the switching condition C according to the vehicle speed at the time when the input command is input, the processor 10 determines that the control mode switching command is a command that accurately reflects the driver's intention.

[0031] The processor 10 reads the switching condition C associated with the vehicle speed range to which the acquired vehicle speed belongs, compares the input mode of the input command with the input mode information in the switching condition C, and judges whether the switching condition C associated with the vehicle speed range to which the vehicle speed belongs is satisfied. The processor 10 judges the type of the input system determined from the input mode of the input command, and judges that the switching condition C is satisfied when it includes all of the predetermined types of the input system corresponding to the vehicle speed in the switching condition C, that is, when all of the input commands via the input system defined in the switching condition C corresponding to the vehicle speed are complete (inputs can be confirmed). For example, in the switching condition C of FIG. 4, when the vehicle speed VX acquired from the vehicle speed sensor is VX2, the processor 10 refers to the switching condition C associated with the vehicle speed range VR2, compares it with the input mode of the input command, and judges that the switching condition C when the vehicle speed VX=VX2 is satisfied when it is confirmed that the input command has been input via the input system of (1) the main switch 151, (2) the cancel button 154, and (3) the brake operation. At this time, the operation sequence of the input systems may be taken into consideration.

[0032] The processor 10 also counts the number of operations of the input system determined from the input mode of the input command, and determines that the switching condition C is satisfied when the input command is input via an input system that is equal to or higher than the evaluation threshold value AT of the input system corresponding to the vehicle speed in the switching condition C. For example, when the vehicle speed VX acquired from the vehicle speed sensor is VX2, the processor 10 refers to the evaluation threshold value AT2 associated with the vehicle speed range VR2 in the switching condition C. The processor 10 determines that the switching condition C is satisfied when it is confirmed that the number of operations of the input system into which the input command is input is 3 or more. The number of operations of the input system to be counted can be, for example, the number of input commands input within a predetermined time DT from the timing G1 at which an input command via a predefined input system such as the cancel button 154 related to a switching command is first detected.

[0033] Next, the correction function of the switching condition C will be described. The processor 10 corrects the above-mentioned switching condition C according to the difficulty level of lane keeping driving. The processor 10 acquires information on the current position of the vehicle from the vehicle position detection device 12, refers to the map database 13, identifies the lane in which the vehicle is traveling or is scheduled to travel based on the current position of the vehicle, and calculates the difficulty level of lane keeping driving in that lane. The difficulty level of lane keeping driving is determined based on the curve curvature and / or lane width of the lane in which the vehicle is traveling or is scheduled to travel. The processor 10 refers to the map database 13 and calculates the curve curvature and / or lane width of the lane in which the vehicle is traveling or is scheduled to travel. The difficulty level of lane keeping driving may be determined based on the lane detection accuracy, lane recognition accuracy, weather (rainfall, snowfall), etc., using a technology known at the time of filing. If the lane detection accuracy, etc. is lower / worse than a preset standard value, the difficulty level of lane keeping driving becomes higher (more difficult). The degree of difficulty may be expressed as a ratio of the difficulty of lane keeping when driving in a reference lane (with a specified curvature and lane width) to 100, with the difficulty of lane keeping when driving in a target lane being expressed as a ratio to 100.

[0034] The processor 10 corrects the switching condition C associated with the vehicle speed according to the degree of difficulty of lane keeping driving. The processor 10 corrects (the switching condition C) so as to ease the switching condition C when the degree of difficulty of lane keeping driving is relatively high, and ease the switching condition C when the degree of difficulty of lane keeping driving is relatively low. The easing of the switching condition C is a change that reduces or lightens the input load of the input command required according to the vehicle speed when switching control of the control mode is executed. Specifically, the processor 10 can ease the switching condition C by making a correction to delete a part of the predetermined type of the input system in the switching condition C. The processor 10 can ease the switching condition C by correcting the evaluation threshold related to the number of operations of the input system in the switching condition C to a lower value. The processor 10 can ease the switching condition C by correcting the torque threshold for determining the presence or absence of an input operation in the switching condition C to a lower value.

[0035] FIG. 7 shows an example of the relationship between the relaxation of the switching condition C and the difficulty of lane keeping driving. The relaxation coefficient of the switching condition C with respect to the difficulty of lane keeping driving is shown. The relaxation coefficient indicates the ratio of the corrected "switching condition C'" to the reference "switching condition C" corresponding to the same vehicle speed (range). When four types of input systems are defined in the reference switching condition C, the relaxation coefficient when deleting one of the types of input systems is 0.75. When the evaluation threshold for the number of operations is defined as "4" in the reference switching condition C, the relaxation coefficient or correction coefficient when correcting the evaluation threshold to "2" is 0.50. As shown by the solid line in FIG. 7, the relaxation coefficient or correction coefficient may be changed stepwise according to the difficulty of lane keeping driving, or may be changed linearly as shown by the dashed line in the same figure. By relaxing the switching condition C in a situation where it is difficult to continue the control of lane keeping driving, the control mode can be switched to manual driving control with a relatively simple operation without requiring a high operational load from the driver. When it becomes difficult for the driver to continue lane keeping, the driver can easily switch to manual driving control with low-effort operations.

[0036] The switching function of the processor 10 will be described. The control mode switching function is executed when an input command including a switching command for switching from autonomous driving control to manual driving control is input by a user operation while autonomous driving control is being executed (during execution) by the above-mentioned autonomous driving control function. When the processor 10 determines that the input mode of the input command satisfies a switching condition C according to the vehicle speed, it switches the control mode of the vehicle from autonomous driving control to manual driving control. Since the amount of change in the behavior of the vehicle differs depending on the speed, the handover of the control authority (control responsibility) accompanying the change of the control mode from autonomous driving control to manual driving control is required to be performed more accurately and reliably as the vehicle speed increases. The accurate handover of the initiative of the vehicle driving control means that the driver recognizes the handover of the initiative of the driving control and the timing of the handover, and immediately executes the handover of the control authority (the driver inputs an input command for manual driving control immediately after the control mode switching process).

[0037] In this embodiment, the control mode is changed depending on whether the input mode by the driver's input operation satisfies the switching condition C according to the vehicle speed, so that the control mode can be switched from autonomous driving control to manual driving control in accordance with the driver's will, and the initiative of the driving control can be reliably handed over to the driver. As a result, the occurrence of a time lag in the transfer of the initiative of the driving control can be suppressed, so that the handover from autonomous driving control to manual driving control can be reliably executed without imposing an excessive operational burden on the driver during low-speed driving while maintaining driving stability during high-speed driving. When an input command of an input mode that satisfies the switching condition C according to the vehicle speed is acquired, it can be determined with high accuracy that the input command requesting the switch input while driving at that vehicle speed is based on the driver's will. As a result, the switch from autonomous driving control to manual driving control can be executed in accordance with the driver's will, and the initiative of the driving control can be handed over in accordance with the driver's intention.

[0038] In addition, since the higher the vehicle speed, the greater the change in vehicle behavior per unit time, the higher the vehicle speed when changing the control mode to manual driving control, the more important it becomes to confirm the driver's intention. When the vehicle speed is relatively high and the control mode is switched to manual driving control, the processor 10 of this embodiment requests the driver to perform a relatively heavy operation load by increasing the number of types of input systems or increasing the evaluation threshold value for the number of operations of the input systems compared to when the vehicle speed is relatively low. When the vehicle speed is high, operations using more input systems are required to change the control mode (Take Over) than when the vehicle speed is low, so that the driver's intention can be clearly reflected in the operation (motion).

[0039] On the other hand, if it is determined that the input mode of the input command does not satisfy the switching condition C according to the vehicle speed, the control mode is prohibited from being switched from autonomous driving control to manual driving control. If the input input command does not satisfy the switching condition C that defines an input operation that involves a sufficient operational load in advance, it is determined that the input command is not based on the driver's intention. If the control mode is changed by a switching command that is not based on the driver's intention, the driver will not expect the initiative in driving control to be taken over and will be confused, so it takes time from the end of autonomous driving control to the start of manual driving control by the driver.

[0040] In this way, when the autonomous driving control is switched to the manual driving control by an operation (misoperation) that is not based on the driver's intention, the driver cannot grasp the situation in which he or she must take the initiative in driving, and therefore the driver cannot immediately start driving. For this reason, a time lag occurs between the end of the autonomous driving control and the start of the manual driving control by the driver. Since the movement amount per unit time of a vehicle traveling at high speed is large, the occurrence of a time lag during takeover while traveling at high speed is undesirable even if it is short, and the occurrence itself should be suppressed. In contrast, in this embodiment, the control mode is changed to the manual driving control after determining that the input command is based on the driver's intention based on the switching condition C, so that the initiative in driving control can be immediately handed over to the driver under the confirmed driver's intention.

[0041] In this embodiment, in the switching condition C, a relatively high operational load is stipulated when the vehicle speed is relatively high, so that the driver is required to perform a high-load input operation. By executing a high-load input operation when the vehicle speed is high, the driver's intention regarding the switching command can be confirmed. By transferring the initiative of the driving control based on the driver's recognition, the driver can start manual driving control immediately after the autonomous driving control ends, so that the initiative of the driving control can be handed over to the driver without causing a time lag between the driver's awareness and the change of the control mode. In this embodiment, the switching condition C specifies a relatively low operational load when the vehicle speed is relatively low. During low-speed driving, a situation where stopping and starting are repeated, such as driving in a traffic jam, is assumed, and there is a possibility that the control mode is frequently switched. In this example, the type of input system and the number of operations via the input system are reduced at low speeds compared to high speeds, so that the operational load on the driver at low speeds where start / stop are repeated can be reduced while the driver's intention is reliably confirmed by increasing the operational load at high speeds.

[0042] The switching function will be described. When the control mode is switched to manual driving control, the processor 10 sends a command to that effect to the drive control device 17 to cancel the autonomous driving control and starts driving by manual driving control according to the manual driving operation. In addition, the fact that the control mode has been switched to manual driving control may be presented on the presentation device 16.

[0043] FIG. 8 is a flowchart showing the procedure of the driving control according to the present embodiment. The processor 10 acquires the current position via the vehicle position detection device 12 at a predetermined cycle (S1), acquires an input command from the driver via the input device 15 (S1a), acquires the vehicle speed via the sensor 11 (S1b), and acquires information on the driving situation by referring to the map database 13 (S1c). The processor 10 calculates the route along which the vehicle will travel based on the acquired information (S2). The processor 10 judges whether or not autonomous driving control is possible (S3). The processor 10 judges that autonomous driving control is possible when predetermined autonomous driving execution conditions are satisfied, such as the ability to refer to high-precision map information of the driving route, the ability to accurately detect and identify lanes, and the ability of the driver to be awake. When it is judged that autonomous driving control is possible, an autonomous driving control command is calculated (S4), and the drive control device 17 is caused to execute autonomous driving control based on the autonomous driving control command (S5). The autonomous driving control is executed by the autonomous driving control function of the processor 10. If autonomous driving control is not possible, the process from step S1 onwards is repeated while continuing manual driving control.

[0044] The processor 10 acquires input mode information from the information of the input command acquired in S1a (S6). The processor 10 acquires, as the input mode information, the type (identification information) of the input system into which the input command was input. The processor 10 counts the types of input systems of a series of input commands input within a predetermined time from the timing at which the input of the first input command was detected, and acquires the number of operations of the input system as the input mode information.

[0045] The processor 10 reads the switching condition C according to the acquired vehicle speed (S7). The processor 10 may acquire the input torque of the input operation when the input command is input as the input mode information (S8). The processor 10 refers to the switching condition C according to the vehicle speed, and when the input torque of the input operation is equal to or greater than the torque threshold value in the switching condition C, determines that the input command has been input (S9: YES). The processor 10 extracts the input command input with an input torque equal to or greater than the torque threshold value, and determines whether the switching condition C is satisfied or not. If NO in S9, the process may return to step S1. Note that steps S8 and S9 may be skipped, and the process may proceed from step S7 to step S10 according to the flow indicated by the dashed line.

[0046] The processor 10 compares the input mode of the acquired input command with the input mode information (type of input system, number of operations) of the switching condition C according to the referenced vehicle speed (S10). As a result of the comparison, the processor 10 judges whether the input mode of the input command satisfies the switching condition C (S11). If it is judged that the switching condition C is satisfied (YES in S11), the processor 10 executes the switching control (S12). The processor 10 switches the control mode from autonomous driving control to manual driving control, and causes the vehicle to be driven by the manual driving control (S13). If it is judged that the manual driving control is to be switched back to autonomous driving control, the autonomous driving control is executed (S14). The processor 10 returns to step S1 and waits for the transition to manual driving control.

[0047] In step S7, a process may be performed to correct the switching condition C according to the referenced vehicle speed. The processor 10 acquires the degree of difficulty of continuing lane keeping driving control, specifically, the curve curvature and / or lane width of the driving lane (S21). The processor 10 corrects the content of the switching condition C associated with the vehicle speed according to the degree of difficulty of lane keeping driving in the lane in which the vehicle is driving or will be driving (S22). The processor 10 reads the corrected switching condition C as a new standard (S23). Steps S21-S23 can be skipped. [Explanation of symbols]

[0048] 100... driving control system, 1... driving control device, 10... processor, 11... sensor, 12... vehicle position detection device, 13... map database, 14... in-vehicle equipment, 15... input device, 16... presentation device, 17... drive control device, 20... communication device

Claims

1. A method for controlling a driving of a vehicle, the method including switching control of a control mode between an autonomous driving control of the vehicle and a manual driving control of the vehicle by a driver, The processor of the operation control device counting the number of operations of the input system into which the input command was input, the input command being determined from the input mode of the input command input by the driver's input operation; Acquire a vehicle speed of the vehicle; a switching condition that is pre-associated with the vehicle speed and an evaluation threshold for the number of operations of the input system as input mode information of the input command, such that the evaluation threshold for the number of operations of the input system required to execute the switching control of the control mode becomes higher as the vehicle speed becomes higher, and a determination is made as to whether or not the counted number of operations of the input system as the input mode satisfies the switching condition based on the evaluation threshold for the number of operations of the input system associated with the acquired vehicle speed; When the number of operations of the input system is equal to or greater than the evaluation threshold value corresponding to the vehicle speed, it is determined that the switching condition is satisfied; When it is determined that the input manner of the input command satisfies the switching condition, the control mode of the vehicle is switched from the autonomous driving control to the manual driving control; A driving control method for driving the vehicle through the manual driving control.

2. the input mode is a type of the input system through which the input command is input, The driving control method according to claim 1 , wherein the processor determines a type of the input system of the input command, and determines that the switching condition is satisfied if the type of the input system includes a predetermined type corresponding to the vehicle speed.

3. 3. The driving control method according to claim 1, wherein the processor counts the number of operations of the input system, refers to the switching condition defined as the input mode information as an evaluation threshold for the number of operations of the input system corresponding to the vehicle speed, and determines that the switching condition is satisfied if the number of operations of the input system is equal to or greater than the evaluation threshold corresponding to the vehicle speed.

4. The driving control method described in claim 3, wherein the switching condition is defined so that a first evaluation threshold for the number of operations of the input system corresponding to the vehicle speed equal to or greater than a predetermined vehicle speed threshold is higher than a second evaluation threshold for the number of operations of the input system corresponding to the vehicle speed less than the predetermined vehicle speed threshold.

5. The driving control method according to any one of claims 1 to 4, wherein the processor refers to a map database, calculates the degree of difficulty of lane keeping in the lane in which the vehicle is traveling or is scheduled to travel based on the current position of the vehicle, and when it is determined that the degree of difficulty of lane keeping is equal to or greater than a predetermined threshold, makes a correction to relax the switching condition associated with the vehicle speed.

6. The driving control method according to any one of claims 1 to 5, wherein the processor refers to a map database, calculates a curve curvature of the lane in which the vehicle is traveling or is scheduled to travel based on the current position of the vehicle, and when it is determined that the curve curvature of the lane in which the vehicle is traveling or is scheduled to travel is equal to or greater than a curve threshold, makes a correction to relax the switching condition associated with the vehicle speed.

7. The driving control method according to any one of claims 1 to 6, wherein the processor refers to a map database, calculates the lane width of the lane in which the vehicle is traveling or is scheduled to travel based on the current position of the vehicle, and when it is determined that the lane width of the lane in which the vehicle is traveling or is scheduled to travel is less than a width threshold, makes a correction to relax the switching condition corresponding to the vehicle speed.

8. the input mode includes an input torque of the input operation by which the input command is input, The driving control method according to any one of claims 1 to 7, wherein the processor acquires the input torque of the input operation, refers to the switching condition in which a torque threshold value of the input torque corresponding to the vehicle speed is defined as the input mode information, and determines that the input operation has been input if the input torque is equal to or greater than the torque threshold value corresponding to the vehicle speed.

9. 9. The driving control method according to claim 8, wherein the switching condition is defined such that a first torque threshold of the input torque corresponding to the vehicle speed equal to or greater than a predetermined vehicle speed threshold is smaller than a second torque threshold of the input torque corresponding to the vehicle speed less than the predetermined vehicle speed threshold.

10. A driving control method as claimed in any one of claims 1 to 9, wherein the switching conditions are set to a first vehicle speed range VR1 (VX1≧V2), a second vehicle speed range VR2 (V2>VX2≧V1), a third vehicle speed range VR3 (V1>VX3≧V0), and a fourth vehicle speed range VR4 (V0>VX4), which are relatively high, and a first evaluation threshold AT1 (>AT2) is associated with the first vehicle speed range VR1, a second evaluation threshold AT2 (>AT3) is associated with the second vehicle speed range VR2, a third evaluation threshold AT3 (>AT4) is associated with the third vehicle speed range VR3, and a fourth evaluation threshold AT4 (=1) is associated with the fourth vehicle speed range VR4, so that the evaluation threshold for the number of operations of the input system required to execute the switching control of the control mode is higher for the higher vehicle speed ranges.

11. A driving control device for a vehicle that executes control mode switching between autonomous driving control of the vehicle and manual driving control of the vehicle by a driver, The processor of the operation control device a process of counting the number of operations of the input system through which the input command is input, the number being determined from an input mode of the input command input by the input operation of the driver; A process of acquiring a vehicle speed of the vehicle; a process of determining whether or not the counted number of operations of the input system as the input mode satisfies a switching condition based on an evaluation threshold for the number of operations of the input system associated with the vehicle speed, the switching condition being pre-associated with the vehicle speed such that the evaluation threshold for the number of operations of the input system required to execute the switching control of the control mode becomes higher as the vehicle speed becomes higher; determining that the switching condition is satisfied when the number of operations of the input system is equal to or greater than the evaluation threshold value corresponding to the acquired vehicle speed; When it is determined that the input manner of the input command satisfies the switching condition according to the vehicle speed, a process of switching the control mode of the vehicle from the autonomous driving control to the manual driving control; and a driving control device that executes a process of driving the vehicle through the manual driving control.

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