Driving control method and driving control device

Abstract

The processor (10) of the drive control device (100) controls driving of the host vehicle at a prescribed drive assist level, determines whether or not a transition request requesting transition of the drive assist level from a first drive assist level to a second drive assist level higher than the first drive assist level is input, and relaxes a transition condition for transitioning the drive assist level from the first drive assist level to the second drive assist level in the case where the transition request is input.

Description

TECHNICAL FIELD

[0001] The present application relates to a driving control method and a driving control device. BACKGROUND

[0002] The driving control method described in Patent Document 1 is a method in which a target travel path of the host vehicle is divided into a plurality of sections, and a criterion for allowing driving assist control is set for each section.

[0003] PRIOR ART DOCUMENTS

[0004] PATENT DOCUMENTS

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-170402

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] However, in the driving control method described in Patent Document 1, even if the occupant of the host vehicle desires to increase the driving assist level, depending on the section in which the host vehicle is traveling, the driving assist level can be difficult to increase compared to other sections. SUMMARY

[0008] The problem to be solved by the present application is to provide a driving control method and a driving control device in which the driving assist level is easily increased when a transition request to increase the driving assist level is input.

[0009] The present application solves the above problem by determining whether a transition request to transition the driving assist level from a first driving assist level to a second driving assist level higher than the first driving assist level is input, and relaxing (mitigating) a transition condition for transitioning the driving assist level from the first driving assist level to the second driving assist level when the transition request is input, relative to when the transition request is not input.

[0010] EFFECT OF THE INVENTION

[0011] According to the present application, the transition condition is relaxed when the transition request is input, so in the case where a transition request to increase the driving assist level is input, the effect of the driving assist level being easily increased is achieved. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 is a block diagram showing the structure of the driving control device of the present embodiment.

[0013] Figure 2 is a diagram showing an example of the positional relationship between the host vehicle and the preceding vehicle.

[0014] Figure 3is a graph indicating an example of a relationship between the vehicle speed of the host vehicle and a vehicle speed threshold value for changing the driving assist level.

[0015] Figure 4 is a graph indicating an example of a relationship between the vehicle speed of the host vehicle and a vehicle speed threshold value for changing the driving assist level, is a graph indicating an example in which the vehicle speed threshold value shown in Figure 3 is changed to a high value.

[0016] Figure 5 is a flowchart indicating the order of a driving control method executed by the driving control device shown in Figure 1 DETAILED DESCRIPTION

[0017] Hereinafter, an embodiment of the present application will be described based on the drawings.

[0018] Figure 1 is a block diagram indicating the structure of the host vehicle 1 and the driving control device 100 for controlling autonomous driving of the host vehicle 1. The host vehicle 1 is provided with: the driving control device 100, a detection device 101, a host vehicle position acquisition section 102, a map database 103, an in-vehicle device 104, an input device 105, a user interface 106, and a drive control device 107.

[0019] ​The drive control device 100 autonomously controls the vehicle speed and the steering of the host vehicle 1 by the autonomous driving control function by executing a program stored in the ROM by the CPU. The drive control device 100 can set a drive mode corresponding to a drive assist level, and can assist the driving of the host vehicle by the set drive mode. The drive assist level is a level indicating the degree of intervention when the drive control device 100 assists the driving of the vehicle by the autonomous driving control function. The higher the drive assist level, the lower the contribution of the driver to the driving of the vehicle. Specifically, the drive assist level can be set to levels 0 to 5 using the definition based on SAE J3016 of the Society of Automotive Engineers (SAE) or the like. In level 0, the driving operation of the host vehicle is performed entirely manually by the driver. In level 1, the driving operation of the host vehicle is mainly performed by manual driving of the driver, but the drive control device 100 appropriately assists the manual driving of the driver by any one of the functions of automatic braking, following, lane keeping, and the like. In level 2, the driving operation of the host vehicle is mainly performed by manual driving of the driver, but under specific conditions, the drive control device 100 can perform driving assistance by combining a plurality of functions of the functions of automatic braking, following, lane keeping, and the like. In level 3, the drive control device 100 performs all driving tasks, but the driver needs to take over the control with a request from the drive control device 100 and perform driving by hand. In level 4, manual driving of the driver is not required, and the drive control device 100 can perform all driving tasks under specific conditions and monitor the surrounding situation of the host vehicle. In level 5, the drive control device 100 can perform all driving tasks under all conditions.

[0020] In addition, the drive mode corresponding to level 2 is an eyes-on mode. That is, in the case where the drive assist level is set to level 2, the driver needs to monitor the surrounding situation of the host vehicle 1 by vision. In the case where the drive assist level is set to level 2, the orientation of the face and the movement of the eyes of the driver are monitored by a camera in the vehicle or the like, and in the case where the driver visually confirms the front, the host vehicle 1 is allowed to travel. In addition, the drive mode corresponding to level 2 is a hands-on mode. The hands-on mode is a mode in which the autonomous steering control of the processor 10 does not operate in the case where the driver does not hold the steering wheel 104a. In addition, whether or not the driver holds the steering wheel 104a is detected by a touch sensor (not shown) provided on the steering wheel 104a or a steering torque sensor (not shown) of the EPS.

[0021] In addition, "the driver holds the steering wheel 104a" includes not only a state in which the driver tightly holds the steering wheel 104a, but also a state in which the driver lightly holds the steering wheel 104a with a hand.

[0022] On the other hand, the driving mode corresponding to level 3 is an eyes-off mode. That is, in a case where the driving assistance level is set to level 3, the processor 10 controls the driving of the host vehicle 1 by the eyes-off mode that allows the host vehicle 1 to travel in a state where the driver does not visually confirm the front. At this time, the system of the driving control device 100 autonomously monitors the surrounding situation of the host vehicle using a camera, a radar, or the like. In addition, the driving mode corresponding to level 3 is a hands-off mode. The hands-off mode is a mode in which the steering control of the processor 10 operates even if the driver moves the hands from the steering wheel 104a. That is, in a case where the driving assistance level is set to level 3, the processor 10 controls the driving of the host vehicle 1 by the hands-off mode that allows the host vehicle 1 to travel in a state where the driver releases the hands from the steering wheel of the host vehicle 1. In addition, the driving control device 100 can execute the driving mode corresponding to level 3 with the condition that the host vehicle 1 travels behind the preceding vehicle 2 as shown in FIG. 1. Figure 2

[0023] Here, "the host vehicle 1 travels behind the preceding vehicle 2" includes not only a case where the host vehicle 1 follows the preceding vehicle 2 but also a case where the host vehicle 1 does not follow the preceding vehicle 2 and travels on a travel path on which the preceding vehicle 2 has already traveled from behind the preceding vehicle 2. Thus, the driving control device 100 can confirm that there is no obstacle on the travel path on which the preceding vehicle 2 has already traveled, that is, in front of the host vehicle 1, and thereby control the driving of the host vehicle 1. In addition, "the host vehicle 1 follows the preceding vehicle 2" means a case where the host vehicle 1 travels in a state where the driving control device 100 controls the driving of the host vehicle 1 in conjunction with the motion of the preceding vehicle 2 and controls the vehicle speed VI of the host vehicle 1 in such a manner that the host vehicle 1 maintains a certain interval from the preceding vehicle 2

[0024] In addition, the classification of the driving assistance level is not limited to the classification according to the definition of the Society of Automotive Engineers of Japan, and the driving assistance level can be defined based on the ISO / TC204 of the International Organization for Standardization (ISO). In addition, the classification of the driving assistance level can be defined according to other standards as long as it is appropriately classified according to the degree of intervention of the driving control device 100.

[0025] The detection device 101 has either one or both of an on-vehicle camera that captures the surroundings of the host vehicle 1 or a radar that detects other vehicles or obstacles in the surroundings of the host vehicle. The detection result of the detection device 101 is output to the driving control device 100 at a predetermined time interval.

[0026] ​The host vehicle position acquisition section 102 is configured by a GPS unit, a gyro sensor, a vehicle speed sensor, and the like. The host vehicle position acquisition section 102 acquires position information of the host vehicle 1 periodically by detecting radio waves transmitted from a plurality of communication satellites by the GPS unit, and detects a current position of the host vehicle 1 based on the acquired position information of the host vehicle 1, angle change information acquired from the gyro sensor, and vehicle speed acquired from the vehicle speed sensor. The position information of the host vehicle 1 detected by the host vehicle position acquisition section 102 is output to the driving control device 100 at a predetermined time interval.

[0027] The map database 103 is a storage configured to store three-dimensional high-precision map information including position information of various facilities and specific locations, and is accessible from the driving control device 100. High-precision digital map information (high-precision map, dynamic map) is stored in the map database 103. The high-precision map information includes identification information of a plurality of lanes possessed by a road. The map information of the map database 103 includes three-dimensional position information about roads and / or curved roads and the size (for example, curvature or radius of curvature) of the curved roads, merging locations, branching locations, and positions of reduction in the number of lanes. Information about facilities such as service areas and parking areas is also included in the high-precision map information.

[0028] The on-vehicle equipment 104 is various equipment mounted on the vehicle and operated by the driver. The on-vehicle equipment 104 includes a steering wheel 104a. As other on-vehicle equipment 104, an accelerator pedal, a brake pedal, a navigation device, a direction indicator, a wiper, a lamp, a horn, or other specific switches, and the like are exemplified. In a case where the driver operates the on-vehicle equipment 104, the information is output to the driving control device 100.

[0029] The input device 105 is, for example, a button switch capable of input by manual operation of the driver, a touch panel provided on a display screen, or a microphone capable of input by the voice of the driver, or the like.

[0030] The user interface 106 outputs information by image, text, or sound. The user interface 106 is, for example, a display or a microphone. In addition, one touch panel display can function as the input device 105 and the user interface 106.

[0031] The drive control device 107 controls the driving of the host vehicle 1 based on the control command of the driving control device 100. For example, the drive control device 107 controls the operation of a drive mechanism (including the operation of an internal combustion engine in an engine vehicle, the operation of a traveling electric motor in an electric vehicle system, and the torque distribution of an internal combustion engine and a traveling electric motor in a hybrid vehicle) for adjusting the acceleration / deceleration and the vehicle speed and the operation of a brake by an autonomous speed control function. In addition, the drive control device 107 performs steering control of the host vehicle by controlling the operation of a steering wheel actuator by an autonomous steering control function. For example, the drive control device 107 detects a lane marker on a lane in which the host vehicle is traveling, and controls the travel position (lateral position) of the host vehicle in the width direction so that the host vehicle travels in the center of the lane. In addition, the drive control device 107 controls the host vehicle to overtake a preceding vehicle, change the travel direction, and the like. Furthermore, the drive control device 107 performs travel control for right or left turns at intersections and the like. In addition, as the travel control method of the drive control device 107, other publicly known methods can be used.

[0032] Next, the use of the Figures 1 to 4 The configuration of the driving control device 100 will be described in detail.

[0033] In addition, in the following description, the first driving assistance level is set to level 2, and the second driving assistance level is set to level 3. In addition, the relationship between the first driving assistance level and the second driving assistance level is only that the second driving assistance level is relatively higher than the first driving assistance level. The respective driving assistance levels are not limited to level 2 and level 3. In addition, the processor 10 can set a driving mode corresponding to other driving assistance levels in addition to level 2 and level 3.

[0034] As described above, the processor 10 sets the driving mode corresponding to the second driving assistance level when the second driving assistance level is set to level 3. Figure 1As shown, the drive control device 100 is provided with a processor 10. The processor 10 is constituted by a ROM (Read Only Memory) in which a program for controlling driving of the host vehicle is stored, 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. In addition, as an action circuit, instead of or in addition to the CPU (Central Processing Unit), an MPU (Micro Processing Unit), a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or the like can be used. The processor 10 is provided with an evaluation value calculation section 11, a conversion request determination section 12, a conversion condition setting section 13, an evaluation value determination section 14, and a vehicle control section 15. The evaluation value calculation section 11, the conversion request determination section 12, the conversion condition setting section 13, the evaluation value determination section 14, and the vehicle control section 15 execute programs for realizing the respective functions of the processor 10.

[0035] In addition, in Figure 1 the drive control device 100 is mounted on the host vehicle 1, but is not limited thereto, and the drive control device 100 can be a device that remotely operates the host vehicle 1.

[0036] The evaluation value calculation section 11 calculates an evaluation value that indicates the sufficiency (degree of satisfaction) of a conversion condition for converting the driving assistance level from the first driving assistance level to the second driving assistance level that is higher than the first driving assistance level. The conversion condition is, for example, that the host vehicle 1 is traveling at or below a prescribed set speed. In this example, the evaluation value calculation section 11 calculates the evaluation value in such a manner that the evaluation value corresponding to the second vehicle speed that is lower than the first vehicle speed is higher than the evaluation value corresponding to the first vehicle speed. That is, the lower the vehicle speed of the host vehicle 1, the higher evaluation value the evaluation value calculation section 11 calculates and sets.

[0037] In addition, the conversion condition can also be, for example, that the host vehicle 1 is traveling behind the preceding vehicle 2. In this example, as shown in FIG. 2, the evaluation value calculation section 11 calculates the evaluation value in such a manner that the evaluation value corresponding to the distance between the host vehicle 1 and the preceding vehicle 2 is higher than the evaluation value corresponding to the distance between the host vehicle 1 and the preceding vehicle 2. Figure 2As shown, the evaluation value calculation portion 11 calculates the evaluation value in such a manner that the evaluation value corresponding to a second inter-vehicle distance shorter than the first inter-vehicle distance is higher than the evaluation value corresponding to the first inter-vehicle distance, based on the inter-vehicle distance D between the host vehicle 1 and the preceding vehicle 2. That is, the shorter the inter-vehicle distance D between the host vehicle 1 and the preceding vehicle 2, the higher the evaluation value calculated and set by the evaluation value calculation portion 11. In addition, the evaluation value calculation portion 11 can calculate the evaluation value in such a manner that the evaluation value corresponding to a second elapsed time shorter than the first elapsed time is higher than the evaluation value corresponding to the first elapsed time, based on the elapsed time after the preceding vehicle 2 is detected. That is, the shorter the elapsed time after the preceding vehicle 2 is detected, the less likely it is that there is an obstacle on the path on which the preceding vehicle 2 has traveled, and thus the higher the evaluation value calculated and set by the evaluation value calculation portion 11.

[0038] In addition, the conversion condition can be, for example, that congestion has occurred around the host vehicle 1. In this example, the evaluation value calculation portion 11 calculates the evaluation value in such a manner that the evaluation value in the case where congestion has occurred is higher than the evaluation value in the case where congestion has not occurred. In addition, the evaluation value calculation portion 11 determines whether congestion has occurred around the host vehicle 1 based on the vehicle speed V2 of the preceding vehicle 2 and the vehicle speed of another vehicle (not shown) traveling on another lane L2 adjacent to the travel lane LI of the host vehicle 1.

[0039] In addition, the conversion condition can be, for example, that a predetermined time has elapsed after the host vehicle 1 passes through a branch road. In this example, the longer the predetermined time has elapsed after the host vehicle 1 passes through the branch road, the higher the evaluation value calculated and set by the evaluation value calculation portion 11.

[0040] In addition, the conversion condition for increasing the level of driving assistance can include, in addition to the above conditions, that the host vehicle 1 is traveling on a road on which valid high-precision map information is available, that a signal of a Global Navigation Satellite System (GNSS) is valid, that the driver is visually confirming the front, that there is no tollgate, exit of an expressway, merge, intersection, or place where the number of lanes decreases within a vicinity (for example, within about 800 m ahead) of the current position, and that there is no sharp curve of 100 R or less within a vicinity (for example, within about 500 m ahead) of the current position. The evaluation value calculation portion 11 calculates the evaluation value indicating the sufficiency of the condition for converting the level of driving assistance from the first level of driving assistance to the second level of driving assistance based on one or more of the above conditions. For example, the evaluation value calculation portion 11 can calculate the sufficiency for each of the above conditions separately, and calculate the evaluation value by aggregating the calculated sufficiencies.

[0041] In addition, Figure 1The illustrated conversion request determination part 12 determines whether or not a conversion request that requests a conversion of the driving assist level from the first driving assist level to the second driving assist level has been input to the input device 105. Specifically, the conversion request determination part 12 determines whether or not the running environment of the host vehicle 1 satisfies a prescribed convertible condition, and in the case where the running environment of the host vehicle 1 satisfies the convertible condition, outputs a notification that asks whether or not the driving assist level is to be raised to the user interface 106. The occupant of the host vehicle 1 decides whether or not to accept the conversion of the driving assist level based on the notification output to the user interface 106, and in the case where the conversion of the driving assist level is accepted, inputs the conversion request to the input device 105. The conversion request is input by the occupant of the host vehicle 1 operating the touch panel of the input device 105, or pressing a prescribed button switch. In addition, the occupant of the host vehicle 1 can also voice-input the conversion request to the microphone of the input device 105. In addition, the convertible condition is a necessary condition for becoming a state in which the driving assist level of the host vehicle 1 is able to be converted from the first driving assist level to the second driving assist level. In addition, the convertible condition is also a condition for notifying the occupant of the host vehicle 1 that the driving assist level is able to be converted from the first driving assist level to the second driving assist level. The convertible condition is constituted, for example, by any one or more of the conditions of the vehicle speed of the host vehicle 1 falling below a prescribed speed, a preceding vehicle being detected in front of the host vehicle 1, the distance of the host vehicle 1 from the preceding vehicle becoming a prescribed distance or less, congestion occurring within a prescribed distance in front of the host vehicle 1 on the running intended path of the host vehicle 1, and the like.

[0042] In addition, the conversion condition setting part 13 sets a conversion condition for converting the driving assist level from the first driving assist level to the second driving assist level. In addition, the conversion condition is set to be more strict than the convertible condition set by the conversion request determination part 12. In addition, the conversion condition setting part 13 has an evaluation threshold value setting part 13a. The evaluation threshold value setting part 13a sets an evaluation threshold value that becomes a criterion for determining whether or not to convert the driving assist level from the first driving assist level to the second driving assist level. That is, the evaluation threshold value setting part 13a sets a value corresponding to the conversion condition for converting the driving assist level from the first driving assist level to the second driving assist level as the evaluation threshold value. The evaluation threshold value setting part 13a sets the evaluation threshold value by selecting, in the case where the conversion request has been input, the second evaluation threshold value that is lower than the first evaluation threshold value in the case where the conversion request has not been input, out of the first evaluation threshold value and the second evaluation threshold value that are set in advance. That is, the evaluation threshold value setting part 13a relaxes the conversion condition for converting the driving assist level from the first driving assist level to the second driving assist level in the case where the conversion request has been input, compared to the case where the conversion request has not been input.

[0043] Further, the evaluation value determination unit 14 compares the evaluation value calculated by the evaluation value calculation unit 11 with the evaluation threshold set by the evaluation threshold setting unit 13a, and determines whether the evaluation value is higher than the evaluation threshold. Specifically, Figure 3 and Figure 4 indicates a comparison of the vehicle speed VI and the set speed Vx1, Vx2 in the case where the conversion condition is "the host vehicle 1 is traveling behind the preceding vehicle 2" and "the vehicle speed VI of the host vehicle 1 is equal to or lower than a prescribed set speed Vx1, Vx2". Further, in the example shown in FIG. 10, the evaluation threshold setting unit 13a sets the set speed Vx2 (for example, 60 km / h) in the case where the conversion request is input higher than the set speed Vx1 (for example, 60 km / h) in the case where the conversion request is not input. That is, the evaluation value determination unit 14 determines that the evaluation value is higher than the evaluation threshold in the case where the vehicle speed VI of the host vehicle 1 becomes equal to or lower than the set speed Vx1, Vx2 after the time T11 at which the preceding vehicle 2 is detected. Figure 3 and Figure 4 indicates a comparison of the vehicle speed VI and the set speed Vx1, Vx2 in the case where the conversion condition is "the host vehicle 1 is traveling behind the preceding vehicle 2" and "the vehicle speed VI of the host vehicle 1 is equal to or lower than a prescribed set speed Vx1, Vx2". Further, in the example shown in FIG. 10, the evaluation threshold setting unit 13a sets the set speed Vx2 (for example, 60 km / h) in the case where the conversion request is input higher than the set speed Vx1 (for example, 60 km / h) in the case where the conversion request is not input. That is, the evaluation value determination unit 14 determines that the evaluation value is higher than the evaluation threshold in the case where the vehicle speed VI of the host vehicle 1 becomes equal to or lower than the set speed Vx1, Vx2 after the time T11 at which the preceding vehicle 2 is detected.

[0044] Further, the evaluation value determination unit 14 can determine whether the inter-vehicle distance D between the host vehicle 1 and the preceding vehicle 2 is equal to or lower than a prescribed set inter-vehicle distance, and determine that the evaluation value is higher than the evaluation threshold in the case where the inter-vehicle distance is equal to or lower than the set inter-vehicle distance. Further, the set inter-vehicle distance in the case where the conversion request is input is set longer than the set inter-vehicle distance in the case where the conversion request is not input by the evaluation threshold setting unit 13a.

[0045] Further, the evaluation value determination unit 14 can determine whether the elapsed time from the detection of the preceding vehicle 2 by the detection device 101 is longer than a prescribed set elapsed time, and determine that the evaluation value is higher than the evaluation threshold in the case where the elapsed time is longer than the set elapsed time. Further, the set elapsed time in the case where the conversion request is input is set shorter than the set elapsed time in the case where the conversion request is not input by the evaluation threshold setting unit 13a.

[0046] Further, in the case where congestion occurs around the host vehicle 1 and the conversion request is not input, the evaluation value determination unit 14 can determine that the evaluation value is higher than the evaluation threshold on the condition that the vehicle speed of the preceding vehicle 2 traveling on the same lane LI as the host vehicle 1 is equal to or lower than a prescribed vehicle speed, and the vehicle speed of other vehicles traveling on the adjacent lane L2 is equal to or lower than the prescribed vehicle speed. On the other hand, in the case where the conversion request is input, the evaluation value determination unit 14 can determine that the evaluation value is higher than the evaluation threshold on the condition that the vehicle speed of the preceding vehicle 2 traveling on the lane LI is equal to or lower than the prescribed vehicle speed, regardless of the vehicle speed of other vehicles traveling on the adjacent lane.

[0047] Further, the evaluation value determination unit 14 can determine whether the passing time of the host vehicle 1 after passing the branch road is longer than a prescribed set passing time, and determine that the evaluation value is higher than the evaluation threshold value in the case where the passing time is longer than the set passing time. Further, the passing threshold value setting unit 13a sets the set passing time in the case where the conversion request is input to be shorter than the set passing time in the case where the conversion request is not input.

[0048] Further, the processor 10 can not set the evaluation threshold value, but set the conversion condition depending on whether the conversion request is input. Further, the processor 10 can not perform the calculation of the evaluation value, but determine whether the running environment of the host vehicle 1 satisfies the conversion condition.

[0049] Next, Figure 1 The vehicle control unit 15 illustrated in the drawing controls the driving of the host vehicle 1 so that the driving assistance level is converted from the first driving assistance level to the second driving assistance level in the case where the evaluation value determination unit 14 determines that the evaluation value is higher than the evaluation threshold value and the first driving assistance level controls the host vehicle 1.

[0050] Specifically, in the case where the conversion request is not input, as illustrated in Figure 3 The vehicle control unit 15 illustrated in the drawing converts the driving assistance level from the first driving assistance level to the second driving assistance level at the conversion timing T11 at which the vehicle speed VI becomes the set speed Vx1 or less. On the other hand, in the case where the conversion request is input, as illustrated in Figure 4 The vehicle control unit 15 illustrated in the drawing converts the driving assistance level from the first driving assistance level to the second driving assistance level at the conversion timing T21 at which the vehicle speed V2 becomes the set speed Vx2 or less. Here, the conversion timing T21 in the case where the conversion request is input is earlier than the conversion timing T11 in the case where the conversion request is not input. Further, as illustrated in Figure 4 The vehicle control unit 15 illustrated in the drawing maintains the set speed at the speed Vx2 until the prescribed time Ta elapses after the conversion request is input. That is, the vehicle control unit 15 maintains the evaluation threshold value at the first evaluation threshold value in the case where the conversion request is input until the prescribed time Ta elapses after the conversion request is input. Thus, in the case where the conversion request is input, the set speed is maintained at the speed Vx2 even at the second conversion timing T22 at which the driving assistance level is converted to the second driving assistance level again after the driving assistance level is lowered to the first driving assistance level.

[0051] Further, the vehicle control unit 15 converts the driving assistance level from the first driving assistance level to the second driving assistance level after the prescribed conversion time Tb elapses after the evaluation value becomes a value higher than the evaluation threshold value. The vehicle control unit 15 sets the second conversion time Tb2 (refer to FIG. 6) in the case where the conversion request is input to be shorter than the conversion time Tb in the case where the conversion request is not input. Figure 4) is set to be shorter than the first transition time Tb1 (refer to Figure 3 ) in the case where the transition request is not input. That is, the vehicle control portion 15 causes the driving assist level to be rapidly transitioned from the first driving assist level to the second driving assist level in the case where the transition request is input.

[0052] Next, the steps of the driving control method executed by the driving control device 100 are explained with reference to the flowchart shown in Figure 5

[0053] As shown in Figure 5 , in step S1, the processor 10 determines whether or not the driving of the host vehicle 1 is controlled in the first driving assist level. In the case where the driving assist level is the second driving assist level, the processor 10 ends the processing.

[0054] In the case where the driving assist level is the first driving assist level, in step S2, the processor 10 calculates an evaluation value indicating the sufficiency of the transition condition for transitioning the driving assist level from the first driving assist level to the second driving assist level.

[0055] Next, in step S3, the processor 10 determines whether or not the transition request has been input to the input device 105. In the case where the transition request is not input, in step S4, the processor 10 selects and sets the first evaluation threshold value as the evaluation threshold value. On the other hand, in the case where the transition request has been input, in step S5, the processor 10 selects and sets the second evaluation threshold value lower than the first evaluation threshold value as the evaluation threshold value. That is, the processor 10 relaxes the transition condition in the case where the transition request is input, as compared with the case where the transition request is not input.

[0056] Next, in step S6, the processor 10 determines whether or not the evaluation value is higher than the evaluation threshold value set in step S4 or S5. In the case where the evaluation value is higher than the evaluation threshold value, in step S7, the processor 10 raises the driving assist level and changes from the first driving assist level to the second driving assist level. On the other hand, in the case where the evaluation value is equal to or lower than the evaluation threshold value, in step S8, the processor 10 maintains the driving assist level as the first driving assist level.

[0057] ​As described above, the processor 10 of the driving control device 100 of the present embodiment determines whether or not a transition request requesting a transition of the driving assist level from the first driving assist level to the second driving assist level is input. In a case where the transition request is input, the processor 10 relaxes the transition condition for transitioning the driving assist level from the first driving assist level to the second driving assist level. Thereby, the driving control device 100 can easily increase the driving assist level in a case where the transition request for increasing the driving assist level of the host vehicle 1 is input. Therefore, according to a request of the occupant to increase the driving assist level from the first driving assist level to the second driving assist level, the driving control device 100 can advance the transition timing T21 of the driving assist level from the first driving assist level to the second driving assist level, as shown in FIG. 6. In addition, in a case where the transition request is input, the transition condition for increasing the driving assist level is relaxed, so the frequency of switching the driving assist level becomes less than in a case where the transition request is not input, and the occupant of the host vehicle 1 becomes easy to grasp the timing of switching the driving assist level, as shown in FIG. 7. Figure 4 Figure 4 Figure 3

[0058] In addition, the processor 10 of the driving control device 100 calculates an evaluation value indicating the sufficiency of the transition condition. The driving control device 100 selects, as the evaluation threshold, a second evaluation threshold lower than the first evaluation threshold in a case where the transition request is not input, in a case where the transition request is input. Then, the driving control device 100 controls the driving of the host vehicle 1 so as to transition the driving assist level from the first driving assist level to the second driving assist level in a case where the evaluation value is higher than the evaluation threshold and in a case where the host vehicle 1 is controlled with the first driving assist level. Thereby, the driving control device 100 can set the evaluation threshold in such a manner that the second evaluation threshold in a case where the transition request is input is lower than the first evaluation threshold in a case where the transition request is not input, so the transition condition in a case where the transition request is input can be relaxed compared to the transition condition in a case where the transition request is not input. In addition, the driving control device 100 can determine whether or not to increase the driving assist level based on a comparison between the specific evaluation value and the evaluation threshold.

[0059] Figure 4 In addition, the processor 10 of the driving control device 100 maintains the evaluation threshold as the second evaluation threshold until a prescribed time Ta elapses from when the transition request is input, as shown in FIG. 8. Thereby, the driving control device 100 can again transition the driving assist level from the first driving assist level to the second driving assist level based on the second evaluation threshold during the prescribed time Ta after the transition request is input, even in a case where the driving assist level is returned from the second driving assist level to the first driving assist level.

[0060] ​​​​In addition, the processor 10 of the driving control device 100 sets the conversion time Tb from when the evaluation value becomes a value higher than the evaluation threshold value until the driving assist level is converted from the first driving assist level to the second driving assist level, so that the second conversion time Tb2 in a case where the conversion request is input is shorter than the first conversion time Tb1 in a case where the conversion request is not input. Thus, the driving control device 100 can shorten the time taken for the driving assist level to be converted, in accordance with a request from the occupant to increase the driving assist level from the first driving assist level to the second driving assist level, in a case where the conversion request is input.

[0061] In addition, the processor 10 of the driving control device 100 calculates the evaluation value in such a manner that the evaluation value corresponding to the second vehicle speed of the host vehicle 1 that is lower than the first vehicle speed is higher than the evaluation value corresponding to the first vehicle speed of the host vehicle 1. Thus, the lower the vehicle speed VI of the host vehicle 1, the more easily the driving control device 100 increases the driving assist level from the first driving assist level to the second driving assist level.

[0062] In addition, the processor 10 of the driving control device 100 can also calculate the evaluation value on the basis of the inter-vehicle distance D between the host vehicle 1 and the preceding vehicle 2, in such a manner that the evaluation value corresponding to the second inter-vehicle distance that is shorter than the first inter-vehicle distance is higher than the evaluation value corresponding to the first inter-vehicle distance. Thus, the lower the inter-vehicle distance D between the host vehicle 1 and the preceding vehicle 2, the more easily the host vehicle 1 travels behind the preceding vehicle 2, and the lower the possibility that there is an obstacle between the host vehicle 1 and the preceding vehicle 2, so the driving control device 100 can easily increase the driving assist level from the first driving assist level to the second driving assist level.

[0063] In addition, the processor 10 of the driving control device 100 can also calculate the evaluation value on the basis of the elapsed time after the preceding vehicle 2 is detected in front of the host vehicle 1, in such a manner that the evaluation value corresponding to the second inter-vehicle distance that is shorter than the first inter-vehicle distance is higher than the evaluation value corresponding to the first inter-vehicle distance. Thus, the shorter the elapsed time after the preceding vehicle 2 is detected, the lower the possibility that there is an obstacle or the like in front of the host vehicle 1, so the driving control device 100 can easily increase the driving assist level from the first driving assist level to the second driving assist level.

[0064] Further, the processor 10 of the drive control device 100 can determine whether congestion has occurred around the host vehicle 1 and calculate the evaluation value in such a manner that the evaluation value in a case where congestion has occurred is higher than the evaluation value in a case where congestion has not occurred. Thus, the drive control device 100 is likely to travel following the preceding vehicle 2 behind the preceding vehicle 2 in a case where congestion has occurred around the host vehicle 1 than in a case where congestion has not occurred, and thus can easily raise the driving assistance level from the first driving assistance level to the second driving assistance level.

[0065] The processor 10 of the drive control device 100 controls the driving of the host vehicle 1 when the driving of the host vehicle 1 is controlled at the second driving assistance level by a hand-off mode in which the host vehicle 1 is allowed to travel in a state where the driver has his hands off the steering wheel of the host vehicle 1. Thus, the drive control device 100 can reduce the driving burden on the driver when the driving of the host vehicle 1 is controlled at the second driving assistance level because the driving of the host vehicle 1 is controlled in the hand-off mode.

[0066] The processor 10 of the drive control device 100 controls the driving of the host vehicle 1 when the driving of the host vehicle 1 is controlled at the second driving assistance level by an eye-off mode in which the host vehicle 1 is allowed to travel in a state where the driver does not visually confirm the front. Thus, the drive control device 100 can reduce the driving burden on the driver when the driving of the host vehicle 1 is controlled at the second driving assistance level because the driving of the host vehicle 1 is controlled in the eye-off mode.

[0067] Symbol Explanation

[0068] 1: Host vehicle

[0069] 2: Preceding vehicle

[0070] 100: Drive control device

[0071] 10: Processor

[0072] 11: Evaluation value calculation section

[0073] 12: Conversion request determination section

[0074] 13: Conversion condition setting section

[0075] 15: Vehicle control section

Claims

1. A driving control method, wherein a processor is used to control the driving of the vehicle at a predetermined driving assistance level, wherein, The processor performs the following processing: Determine whether a request has been entered to switch the driving assistance level from a first driving assistance level to a second driving assistance level, which is higher than the first driving assistance level. Compared to the case where no conversion request was entered, when the conversion request was entered, the conversion conditions related to the vehicle's driving environment for switching the driving assistance level from the first driving assistance level to the second driving assistance level are relaxed. When the driving environment of the vehicle meets the switching conditions, the driving of the vehicle is controlled to switch the driving assistance level from the first driving assistance level to the second driving assistance level. The conversion conditions are set to be more stringent than the conversion conditions used to notify the occupants of the vehicle that enable the driving assistance level to be converted from the first driving assistance level to the second driving assistance level.

2. The driving control method as described in claim 1, wherein, The processor performs the following processing: Calculate an evaluation value representing the sufficiency of the stated transition conditions. When the conversion request is entered, a second evaluation threshold, which is lower than the first evaluation threshold when the conversion request is not entered, is selected as the evaluation threshold. If the evaluation value is higher than the evaluation threshold and the vehicle is controlled at the first driving assistance level, the driving of the vehicle is controlled to switch the driving assistance level from the first driving assistance level to the second driving assistance level.

3. The driving control method as described in claim 2, wherein, The processor maintains the evaluation threshold at the second evaluation threshold from the time the conversion request is input until a predetermined time has elapsed.

4. The driving control method as described in claim 2 or 3, wherein, The processor sets the conversion time from when the evaluation value becomes higher than the evaluation threshold until the driving assistance level is converted from the first driving assistance level to the second driving assistance level, such that the second conversion time when the conversion request is input is shorter than the first conversion time when the conversion request is not input.

5. The driving control method as described in claim 2 or 3, wherein, The processor calculates the evaluation value in such a way that the evaluation value corresponding to the second speed of the vehicle, which is lower than the first speed, is higher than the evaluation value corresponding to the first speed of the vehicle.

6. The driving control method as described in claim 2 or 3, wherein, The processor calculates the evaluation value based on the inter-vehicle distance between the vehicle and a preceding vehicle, such that the evaluation value corresponding to a second inter-vehicle distance that is shorter than the first inter-vehicle distance is higher than the evaluation value corresponding to the first inter-vehicle distance.

7. The driving control method as described in claim 2 or 3, wherein, When the processor detects a vehicle traveling in front of the vehicle, it calculates the evaluation value based on the elapsed time after detecting the vehicle in front, in a manner that makes the evaluation value corresponding to a second elapsed time that is shorter than the first elapsed time higher than the evaluation value corresponding to the first elapsed time.

8. The driving control method as described in claim 2 or 3, wherein, The processor performs the following processing: Determine whether congestion has occurred around the vehicle. The evaluation value is calculated in such a way that the evaluation value under congestion conditions is higher than the evaluation value under non-congestion conditions.

9. The driving control method as described in any one of claims 1 to 3, wherein, When the processor controls the driving of the vehicle at the second level of driver assistance, it controls the driving of the vehicle by using a hands-off mode that allows the vehicle to drive while the driver has taken their hands off the steering wheel.

10. The driving control method according to any one of claims 1 to 3, wherein, When the processor controls the driving of the vehicle at the second level of driver assistance, it controls the driving of the vehicle in an eye-off mode that allows the vehicle to drive when the driver has not visually confirmed what is ahead.

11. A driving control device that uses a processor to control the autonomous driving of the vehicle at a predetermined driving assistance level, wherein, have: The conversion request determination unit determines whether a conversion request has been entered that requests the driving assistance level to be converted from a first driving assistance level to a second driving assistance level that is higher than the first driving assistance level. The conversion condition setting unit relaxes the conversion conditions related to the driving environment of the vehicle when the conversion request is input, in contrast to the case where no conversion request is input. The vehicle control unit, when the driving environment of the vehicle meets the switching conditions, controls the driving of the vehicle to switch the driving assistance level from the first driving assistance level to the second driving assistance level. The conversion conditions are set to be more stringent than the conversion conditions used to notify the occupants of the vehicle that enable the driving assistance level to be converted from the first driving assistance level to the second driving assistance level.

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