Operation control method and operation control device

Abstract

A processor 10 of a driving control device 100 compares the speed V1 of a host vehicle 1 which travels in a first lane L1 to the speed of an adjacent vehicle which travels in a second lane L2, determines whether or not the relative speed of an adjacent vehicle 3 with respect to the host vehicle 1 is less than or equal to a prescribed speed difference threshold, and, when the relative speed is less than or equal to the speed difference threshold, relaxes travelling conditions for permitting the host vehicle 1 to travel with a prescribed driving assistance level.

Description

[Technical Field]

[0001] The present invention relates to an operation control method and an operation control device. [Background technology]

[0002] In the driving control method described in Patent Document 1, the driving of the vehicle is controlled at a predetermined driving assistance level so that the vehicle follows the preceding vehicle, and if the lateral movement of the preceding vehicle is greater than a predetermined value, the driving assistance level is lowered. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2020-104802 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the driving control method described in Patent Document 1 sets a driving assistance level according to only the driving environment of the vehicle's own lane, which causes a problem in that there are limited opportunities to set a predetermined driving assistance level.

[0005] The problem to be solved by the present invention is to provide a driving control method and a driving control device that can increase the opportunities to set a predetermined driving assistance level. [Means for solving the problem]

[0006] The present invention compares the vehicle speed of the subject vehicle with the vehicle speed of an adjacent vehicle traveling in an adjacent lane, and when the relative speed of the adjacent vehicle to the subject vehicle is equal to or less than a predetermined speed difference threshold, performs a predetermined driving assistance level. , when the vehicle avoids obstacles The above problem is solved by relaxing the driving conditions for permitting driving. [Effects of the Invention]

[0007] According to the present invention, when the relative speed of an adjacent vehicle to the vehicle is equal to or less than the speed difference threshold, the driving conditions are relaxed, thereby providing the effect of increasing the opportunities to set a predetermined driving assistance level. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a block diagram showing the configuration of an operation control device according to an embodiment of the present invention; [Figure 2] FIG. 10 is a diagram illustrating an example of a host vehicle avoiding an obstacle ahead. [Figure 3] FIG. 2 is a diagram illustrating an example of the positional relationship between a host vehicle, a preceding vehicle, and other adjacent vehicles. [Figure 4] FIG. 10 is a diagram illustrating an example of the positional relationship between the host vehicle, an adjacent vehicle, and a rear vehicle. [Figure 5] 2 is a flowchart showing the steps of an operation control method executed by the operation control device shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 is a block diagram showing the configuration of a host vehicle 1 and a driving control device 100 that controls autonomous driving of the host vehicle 1. The host vehicle 1 includes the driving control device 100, a detection device 101, a host vehicle position acquisition unit 102, a map database 103, an in-vehicle device 104, an input device 105, and a drive control device 106.

[0010] The driving control device 100 autonomously controls the speed and steering of the host vehicle 1 using an autonomous driving control function by executing a program stored in ROM using a CPU. The driving control device 100 can set a driving mode according to the driving assistance level and can assist the driving of the host vehicle according to the set driving mode. The driving assistance level indicates the degree of intervention when the driving control device 100 assists the driving of the vehicle using the autonomous driving control function. The higher the driving assistance level, the lower the driver's contribution to the driving of the vehicle. Specifically, the driving assistance level can be set to levels 0 to 5 using definitions based on SAE J3016 of the Society of Automotive Engineers (SAE). At level 0, the driving operation of the host vehicle is entirely performed manually by the driver. At level 1, the driving operation of the host vehicle is mainly performed manually by the driver, but the driving control device 100 appropriately assists the driver's manual driving using any of functions such as automatic braking, following, and lane keeping. At level 2, the driver is primarily responsible for manual driving of the vehicle, but under certain conditions, the driving control device 100 can perform driving assistance by combining multiple functions, such as automatic braking, following, and lane keeping. At level 3, the driving control device 100 performs all driving tasks, but the driver must regain control and prepare to drive manually when requested by the driving control device 100. At level 4, manual driving by the driver is not required, and the driving control device 100 can perform all driving tasks and monitor the surrounding conditions of the vehicle under certain conditions. At level 5, the driving control device 100 can perform all driving tasks under all conditions.

[0011] The driving mode corresponding to level 2 is eyes-on mode. In other words, when the driving assistance level is set to level 2, the driver needs to visually monitor the situation around the vehicle 1. When the driving assistance level is set to level 2, the direction of the driver's face and eye movements are monitored by an in-vehicle camera, etc., and the vehicle 1 is allowed to drive when the driver is looking ahead. The driving mode corresponding to level 2 is hands-on mode. In hands-on mode, the driver uses the steering wheel 104a If the driver does not have a steering wheel, the autonomous steering control by the processor 10 does not operate. 104a Whether you have a steering wheel or not 104a The torque is detected by a touch sensor (not shown) provided in the EPS or a steering torque sensor (not shown) of the EPS. In addition, "the driver 104a "Having" the driver at the steering wheel 104a Not only is the driver holding the steering wheel firmly, 104a This also includes the state of lightly placing your hand on the

[0012] On the other hand, the driving mode corresponding to level 3 is the eyes-off mode. That is, when the driving assistance level is set to level 3, the processor 10 controls the driving of the host vehicle 1 in the eyes-off mode, which allows the host vehicle 1 to travel when the driver is not looking ahead. At this time, the system of the driving control device 100 autonomously monitors the surroundings of the host vehicle using a camera, radar, etc. Also, the driving mode corresponding to level 3 is the hands-off mode. In the hands-off mode, the driver does not use the steering wheel 104a In this mode, the processor 10 continues to control the steering even when the driver takes their hands off the steering wheel. That is, when the driving assistance level is set to level 3, the processor 10 controls the driving of the vehicle 1 in a hands-off mode that allows the vehicle 1 to travel when the driver takes their hands off the steering wheel of the vehicle 1.

[0013] The classification of driving assistance levels is not limited to the classification according to the definition of the Society of Automotive Engineers, and may be defined based on ISO / TC204 of the International Organization for Standardization (ISO). Furthermore, the classification of driving assistance levels may be defined according to other standards as long as they are appropriately classified according to the degree of intervention by the driving control device 100.

[0014] The detection device 101 has either an on-board camera that captures images of the surroundings of the vehicle 1 or a radar that detects other vehicles and obstacles around the vehicle 1, or both. The detection results of the detection device 101 are output to the driving control device 100 at predetermined time intervals.

[0015] The vehicle position acquisition unit 102 is composed of a GPS unit, a gyro sensor, a vehicle speed sensor, etc. The vehicle position acquisition unit 102 detects radio waves transmitted from multiple satellite communications using the GPS unit, periodically acquires position information of the vehicle 1, and detects the current position of the vehicle 1 based on the acquired position information of the vehicle 1, angle change information acquired from the gyro sensor, and vehicle speed acquired from the vehicle speed sensor. The position information of the vehicle 1 detected by the vehicle position acquisition unit 102 is output to the driving control device 100 at predetermined time intervals.

[0016] The map database 103 is a memory configured to store three-dimensional high-precision map information including position information of various facilities and specific points, and to be accessible from the driving control device 100. The map database 103 stores high-precision digital map information (high-precision maps, dynamic maps). The high-precision map information includes identification information of multiple lanes that a road has. The map information in the map database 103 includes three-dimensional position information about roads and / or lane curves and the magnitude of the curves (e.g., curvature or curvature radius), merging points, branching points, and positions where the number of lanes decreases. The high-precision map information also includes information about facilities such as service areas and parking areas.

[0017] The in-vehicle devices 104 are various devices mounted on the vehicle and are operated by the driver. The in-vehicle devices 104 include a steering wheel 104a. Other in-vehicle devices 104 include an accelerator pedal, a brake pedal, a navigation device, a turn signal, wipers, lights, a horn, and other specific switches. When the in-vehicle devices 104 are operated by the driver, the information is output to the driving control device 100.

[0018] The input device 105 is, for example, a button switch that allows the driver to manually input, a touch panel arranged on a display screen, or a microphone that allows the driver to input by voice.

[0019] The drive control device 106 controls the driving of the host vehicle 1 based on the control commands of the driving control device 100. For example, the drive control device 106 controls the operation of the drive mechanism for adjusting acceleration / deceleration and vehicle speed (including the operation of the internal combustion engine in an engine vehicle, the operation of the traction motor in an electric vehicle, and the torque distribution between the internal combustion engine and the traction motor in a hybrid vehicle) and the brake operation using an autonomous speed control function. The drive control device 106 also controls the steering of the host vehicle by controlling the operation of the steering actuator using an autonomous steering control function. For example, the drive control device 106 detects lane markers of the lane in which the host vehicle is traveling and controls the traveling position (lateral position) of the host vehicle in the width direction so that the host vehicle travels in the center of the lane in which the host vehicle is traveling. The drive control device 106 also controls the host vehicle to overtake a preceding vehicle, change traveling direction, etc. Furthermore, the drive control device 106 performs driving control to turn right or left at an intersection, etc. Other well-known methods can also be used as driving control methods by the drive control device 106. 2, the drive control device 106 executes steering control of the host vehicle 1 so that the host vehicle 1 avoids an obstacle X ahead, based on a control command from the processor 10. That is, the driving control device 100 controls the driving of the host vehicle 1 using the processor 10 so that the host vehicle 1 avoids an obstacle X ahead.

[0020] Next, the configuration of the operation control device 100 will be described in detail with reference to FIGS. In the following description, the "predetermined driving assistance level" is assumed to be level 3, but is not limited to this. The processor 10 can set a driving mode according to another driving assistance level other than level 3.

[0021] As shown in FIG. 1, the driving control device 100 includes a processor 10. The processor 10 includes a read-only memory (ROM) that stores a program for controlling the driving of the host vehicle 1, a central processing unit (CPU) that executes the program stored in the ROM, and a random access memory (RAM) that functions as an accessible storage device. Note that, as the operating circuit, a microprocessing unit (MPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or the like may be used instead of or in addition to the central processing unit (CPU). The processor 10 includes an evaluation value calculation unit 11, a relative speed determination unit 12, a driving condition setting unit 13, an evaluation value determination unit 14, and a vehicle control unit 15. The evaluation value calculation unit 11, the relative speed determination unit 12, the driving condition setting unit 13, the evaluation value determination unit 14, and the vehicle control unit 15 execute programs for implementing the respective functions of the processor 10. In FIG. 1, the driving control device 100 is mounted on the vehicle 1, but the invention is not limited to this, and the driving control device 100 may be a device that remotely controls the vehicle 1.

[0022] The evaluation value calculation unit 11 calculates an evaluation value indicating the degree of fulfillment of a driving condition for permitting the host vehicle 1 to travel at a predetermined driving assistance level (for example, level 3). The driving condition is, for example, that the host vehicle 1 travels at a speed equal to or lower than a predetermined set speed. In this example, the evaluation value calculation unit 11 calculates the evaluation value so that the evaluation value corresponding to a second vehicle speed lower than the first vehicle speed of the host vehicle 1 is higher than the evaluation value corresponding to the first vehicle speed. In other words, the evaluation value calculation unit 11 calculates a higher evaluation value as the vehicle speed V1 of the host vehicle 1 is lower.

[0023] Furthermore, the driving condition for permitting the host vehicle 1 to drive at a predetermined driving assistance level may be, for example, that the host vehicle 1 is driving behind the preceding vehicle 2, as shown in FIG. 3 . In this example, the evaluation value calculation unit 11 calculates the evaluation value based on the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2, such 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. That is, the shorter the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2, the higher the evaluation value calculated by the evaluation value calculation unit 11. Furthermore, the evaluation value calculation unit 11 may calculate the evaluation value based on the elapsed time since the preceding vehicle 2 was detected, such 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. That is, the evaluation value calculation unit 11 calculates the evaluation value higher the shorter the elapsed time since the preceding vehicle 2 was detected, because there is less likelihood that an obstacle exists on the route already traveled by the preceding vehicle 2. In addition, "the subject vehicle 1 is traveling behind the preceding vehicle 2" does not only mean that the subject vehicle 1 is traveling following the preceding vehicle 2, but also means that the subject vehicle 1 is not following the preceding vehicle 2, but is traveling behind the preceding vehicle 2 on the route that the preceding vehicle 2 has already traveled.

[0024] In addition to the above-mentioned conditions, the driving conditions for permitting the host vehicle 1 to travel at a predetermined driving assistance level may include the following: the host vehicle 1 is traveling on a road for which high-precision map information is available; signals from a global navigation satellite system (GNSS) are available; the driver is viewing the road ahead; there are no toll booths, motorway exits, merging points, intersections, or points where the number of lanes decreases near the current location (for example, within approximately 800 meters ahead); and there are no sharp curves with an R of 100 or less near the current location (for example, within approximately 500 meters ahead). The evaluation value calculation unit 11 calculates an evaluation value indicating the degree of fulfillment of the driving conditions for permitting the host vehicle 1 to travel at a predetermined driving assistance level based on one or more of the above-mentioned conditions. For example, the evaluation value calculation unit 11 may calculate the degree of fulfillment for each of the above-mentioned conditions and calculate the evaluation value by adding up the calculated degrees of fulfillment.

[0025] 3, when the detection device 101 detects an adjacent vehicle 3 traveling in the second lane L2, the relative speed determination unit 12 compares the vehicle speed V1 of the host vehicle 1 with the vehicle speed V3 of the adjacent vehicle 3 to determine whether the relative speed of the adjacent vehicle 3 to the host vehicle 1 is equal to or less than a predetermined speed difference threshold. The relative speed of the adjacent vehicle 3 to the host vehicle 1 is the absolute value of the speed difference between the vehicle speed V1 of the host vehicle 1 and the vehicle speed V3 of the adjacent vehicle 3. The speed difference threshold is set based on whether, when the host vehicle 1 changes lanes to the second lane L2, acceleration / deceleration control enables the host vehicle 1 to travel behind the adjacent vehicle 3 while maintaining a predetermined inter-vehicle distance within a predetermined time. When multiple adjacent vehicles 3 are detected, the relative speed determination unit 12 may calculate the average vehicle speed of the multiple adjacent vehicles 3 as the vehicle speed V3 of the adjacent vehicle 3. In addition, if there are adjacent lanes (second lanes) on either side of the first lane L1, the relative speed determination unit 12 selects the vehicle speed V3 of the adjacent vehicle 3 traveling at a speed closer to the vehicle speed V1 of the host vehicle 1 from among the multiple adjacent vehicles 3 traveling in the second lanes L2, and calculates the relative speed.

[0026] 4, when there is a rear vehicle 4 within a predetermined distance behind the host vehicle 1, the relative speed determination unit 12 selects and sets a second speed difference threshold that is lower than the first speed difference threshold when there is no rear vehicle 4 as the speed difference threshold. In other words, when there is a rear vehicle 4 within a predetermined distance behind the host vehicle 1, the relative speed determination unit 12 sets the speed difference threshold lower than when there is no rear vehicle 4. Note that the predetermined distance is the upper limit of the inter-vehicle distance at which acceleration or deceleration of the host vehicle 1 is predicted to affect the rear vehicle 4.

[0027] Furthermore, the driving condition setting unit 13 sets driving conditions for permitting the host vehicle 1 to drive at a predetermined driving assistance level depending on whether the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is equal to or less than a predetermined speed difference threshold. The driving condition setting unit 13 has an evaluation threshold setting unit 13a. The evaluation threshold setting unit 13a sets an evaluation threshold that serves as a criterion for determining whether the host vehicle 1 is allowed to change lanes from the first lane L1 to the second lane L2 at the predetermined driving assistance level. That is, the evaluation threshold setting unit 13a sets conditions for allowing the host vehicle 1 to change lanes from the first lane L1 to the second lane L2 at the predetermined driving assistance level, and sets a value corresponding to the set condition as the evaluation threshold. When the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is equal to or less than the speed difference threshold, the evaluation threshold setting unit 13a selects and sets a second evaluation threshold as the evaluation threshold that is lower than the first evaluation threshold when the relative speed is higher than the speed difference threshold. That is, when the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is equal to or less than the speed difference threshold, the evaluation threshold setting unit 13a relaxes the driving conditions for permitting the host vehicle 1 to drive at a predetermined driving assistance level, compared to when the relative speed is higher than the speed difference threshold. Specifically, when the evaluation threshold setting unit 13a sets that the vehicle speed V1 of the host vehicle 1 is equal to or less than a predetermined set speed as the driving condition for permitting the host vehicle 1 to drive at a predetermined driving assistance level, the evaluation threshold setting unit 13a sets the set speed (e.g., 65 km / h) when the relative speed is equal to or less than the speed difference threshold to be higher than the set speed (e.g., 60 km / h) when the relative speed is higher than the speed difference threshold. That is, when the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is equal to or less than the speed difference threshold, the driving condition setting unit 13 relaxes the driving conditions for permitting the host vehicle 1 to drive at a predetermined driving assistance level.

[0028] In addition, "making the vehicle 1 capable of changing lanes from the first lane L1 to the second lane L2 at a predetermined driving assistance level" means that the driving control device 100 controls the driving of the vehicle 1 traveling on the first lane L1 at a predetermined driving assistance level, and when a lane change becomes necessary, causes the vehicle 1 to change lanes from the first lane L1 to the second lane L2 while maintaining the predetermined driving assistance level.

[0029] Furthermore, 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 to determine whether the evaluation value is higher than the evaluation threshold. Specifically, if the evaluation threshold setting unit 13a sets the condition for permitting the host vehicle 1 to change lanes at a predetermined driving assistance level that the vehicle speed V1 of the host vehicle 1 is equal to or lower than a predetermined set speed, the evaluation value determination unit 14 determines that the evaluation value is higher than the evaluation threshold when the vehicle speed V1 of the host vehicle 1 becomes equal to or lower than the set speed.

[0030] Furthermore, the evaluation value determination unit 14 may determine whether the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2 is equal to or less than a predetermined set inter-vehicle distance, and determine that the evaluation value is higher than the evaluation threshold when the inter-vehicle distance is equal to or less than the predetermined set inter-vehicle distance. Note that the evaluation threshold setting unit 13a sets the set inter-vehicle distance when the relative speed is equal to or less than the speed difference threshold so that it is longer than the set inter-vehicle distance when the relative speed is higher than the speed difference threshold.

[0031] Furthermore, the evaluation value determination unit 14 may determine whether the time elapsed since the detection device 101 detected the preceding vehicle 2 is longer than a predetermined set elapsed time, and if the elapsed time is longer than the set elapsed time, determine that the evaluation value is higher than the evaluation threshold. Note that the evaluation threshold setting unit 13a sets the set elapsed time when the relative speed is equal to or less than the speed difference threshold so that it is shorter than the set elapsed time when the relative speed is higher than the speed difference threshold.

[0032] The vehicle control unit 15 shown in FIG. 1 permits the host vehicle 1 to travel at a predetermined driving assistance level when the evaluation value is higher than the evaluation threshold. That is, when the evaluation value is higher than the evaluation threshold, the vehicle control unit 15 allows the host vehicle 1 to change lanes from the first lane L1 to the second lane L2 at the predetermined driving assistance level. Specifically, when the evaluation value is higher than the evaluation threshold, the vehicle control unit 15 controls the driving of the host vehicle 1 traveling in the first lane L1 at the predetermined driving assistance level, regardless of whether or not there is a preceding vehicle 2. Then, as shown in FIG. 2, when an obstacle X is detected ahead of the host vehicle 1, the vehicle control unit 15 changes lanes from the first lane L1 to the second lane L2 while maintaining the predetermined driving assistance level. This allows the host vehicle 1 to avoid the obstacle X at the predetermined driving assistance level. Note that the vehicle control unit 15 executes lane change control of the host vehicle 1 so that the host vehicle 1 travels behind the adjacent vehicle 3 after changing lanes. However, the present invention is not limited to this, and the vehicle control unit 15 may control the host vehicle 1 to travel ahead of the adjacent vehicle 3. Furthermore, after executing lane change control for the host vehicle 1, the vehicle control unit 15 may again change lanes of the host vehicle 1 from the second lane L2 to the first lane L1. On the other hand, if the evaluation value is equal to or less than the evaluation threshold, the vehicle control unit 15 does not permit the host vehicle 1 to travel at a predetermined driving assistance level. Therefore, when an obstacle X is detected ahead, the host vehicle 1 avoids the obstacle X at a driving assistance level (for example, level 2) lower than the predetermined driving assistance level.

[0033] 3 and 4, when an adjacent vehicle 3 is traveling ahead of the host vehicle 1, the vehicle control unit 15 controls the vehicle speed V1 of the host vehicle 1 traveling in the first lane L1 so that the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is equal to or less than the speed difference threshold. That is, the vehicle control unit 15 controls the vehicle speed V1 of the host vehicle 1 so that the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is maintained at or less than the speed difference threshold. When controlling the vehicle speed V1 so that the relative speed is equal to or less than the speed difference threshold, the vehicle control unit 15 also controls the driving of the host vehicle 1 so that no other vehicle is traveling alongside the host vehicle 1.

[0034] The processor 10 may set the driving conditions depending on whether the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is equal to or less than a predetermined speed difference threshold, without setting an evaluation threshold. The processor 10 may also determine whether the driving environment of the host vehicle 1 satisfies the driving conditions, without calculating an evaluation value.

[0035] Next, the procedure of the operation control method executed by the operation control device 100 will be described with reference to the flowchart shown in FIG. As shown in FIG. 5, in step S1, the evaluation value calculation unit 11 of the processor 10 calculates an evaluation value indicating the degree of fulfillment of the driving conditions for permitting the host vehicle 1 to drive at a predetermined driving assistance level.

[0036] Next, in step S2, the relative speed determination unit 12 calculates the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 based on the vehicle speed V3 of the adjacent vehicle 3 acquired by the detection device 101.

[0037] Next, in step S3, the relative speed determination unit 12 determines whether the relative speed calculated in step S2 is equal to or less than the speed difference threshold. If it is determined in step S3 that the relative speed is not equal to or less than the speed difference threshold, that is, that the relative speed is higher than the speed difference threshold, then in step S4 the evaluation threshold setting unit 13a selects and sets the first evaluation threshold as the evaluation threshold. On the other hand, if it is determined in step S3 that the relative speed is equal to or less than the speed difference threshold, then in step S5 the evaluation threshold setting unit 13a selects and sets a second evaluation threshold that is lower than the first evaluation threshold as the evaluation threshold.

[0038] Next, in step S6, the evaluation value determination unit 14 determines whether the evaluation value is higher than the evaluation threshold. If the evaluation value is higher than the evaluation threshold, in step S7, the vehicle control unit 15 permits the host vehicle 1 to travel at a predetermined driving assistance level. That is, in step S7, the vehicle control unit 15 puts the host vehicle 1 in a state where the host vehicle 1 can change lanes from the first lane L1 to the second lane L2 at the predetermined driving assistance level. On the other hand, if the evaluation value is equal to or lower than the evaluation threshold, in step S8, the vehicle control unit 15 does not permit the host vehicle 1 to travel at the predetermined driving assistance level. That is, if the evaluation value is equal to or lower than the evaluation threshold, the driving control device 100 controls the driving of the host vehicle 1 at a level lower than the predetermined driving assistance level (for example, level 2) when the host vehicle 1 changes lanes from the first lane L1 to the second lane L2.

[0039] As described above, the processor 10 of the driving control device 100 in this embodiment compares the vehicle speed V1 of the host vehicle 1 traveling on the first lane L1 with the vehicle speed V3 of the adjacent vehicle 3 traveling on the second lane L2, and determines whether the relative speed of the adjacent vehicle 3 relative to the host vehicle 1 is equal to or less than a predetermined speed difference threshold. If the relative speed is equal to or less than the speed difference threshold, the processor 10 relaxes the driving conditions for allowing the host vehicle 1 to travel at a predetermined driving assistance level. This allows the driving control device 100 to perform driving control of the host vehicle 1 at a driving assistance level that corresponds to the driving environment of the second lane L2, which is the adjacent lane. In other words, the driving control device 100 can increase the opportunities to set a predetermined driving assistance level. For example, as shown in FIG. 2, in an emergency such as when there is an obstacle X ahead of the host vehicle 1 traveling on the first lane L1, the driving control device 100 can execute lane change control of the host vehicle 1 at a predetermined driving assistance level according to the driving environment of the second lane L2 (the relative speed of adjacent vehicles 3 relative to the host vehicle 1), thereby enabling the host vehicle 1 to smoothly avoid the obstacle X while traveling.

[0040] The processor 10 of the driving control device 100 also calculates an evaluation value indicating the degree of fulfillment of driving conditions for permitting the host vehicle 1 to drive at a predetermined driving assistance level. The processor 10 also selects a second evaluation threshold, which is lower than the first evaluation threshold when the relative speed of the adjacent vehicle 3 relative to the host vehicle 1 is higher than the speed difference threshold, as the evaluation threshold. If the evaluation value is higher than the evaluation threshold, the driving control device 100 permits the host vehicle 1 to drive at the predetermined driving assistance level. As a result, if the evaluation value is higher than the evaluation threshold, the driving control device 100 can enable the host vehicle 1 to change lanes from the first lane L1 to the second lane L2 at the predetermined driving assistance level. Therefore, as shown in FIG. 2 , if an obstacle X is located ahead of the host vehicle 1 traveling on the first lane L1, the host vehicle 1 can smoothly avoid the obstacle X while maintaining the predetermined driving assistance level. The driving control device 100 can also determine whether to permit the host vehicle 1 to drive at the predetermined driving assistance level based on a comparison between a specific evaluation value and the evaluation threshold.

[0041] Furthermore, when there is another vehicle 4 behind within a predetermined distance Dx behind the host vehicle 1, the processor 10 of the driving control device 100 selects a second speed difference threshold that is lower than the first speed difference threshold when there is no other vehicle 4 behind as the speed difference threshold. As a result, when there is a possibility that the other vehicle 4 behind will be affected by the acceleration or deceleration of the host vehicle 1, the driving control device 100 tightens the conditions for determining that the relative speed is equal to or less than the speed difference threshold, thereby suppressing the driving of the host vehicle 1 at a predetermined driving assistance level.

[0042] Furthermore, when the adjacent vehicle 3 is traveling ahead of the host vehicle 1, the processor 10 of the driving control device 100 controls the vehicle speed V1 of the host vehicle 1 so that the relative speed of the adjacent vehicle 3 with respect to the host vehicle 1 is equal to or less than the speed difference threshold. In this way, the driving control device 100 controls the vehicle speed V1 of the host vehicle 1 while maintaining the relative speed equal to or less than the speed difference threshold, so that if an obstacle X is detected ahead, for example, the host vehicle 1 can change lanes to the second lane L2 without significant acceleration or deceleration.

[0043] Furthermore, the processor 10 of the driving control device 100 calculates the evaluation value so that the evaluation value corresponding to the second vehicle speed of the host vehicle 1, which is lower than the first vehicle speed, is higher than the evaluation value corresponding to the first vehicle speed of the host vehicle 1. As a result, the driving control device 100 is more likely to permit the host vehicle 1 to travel at a predetermined driving assistance level the lower the vehicle speed V1 of the host vehicle 1. In other words, when an obstacle X is detected ahead, for example, the lower the vehicle speed V1 of the host vehicle 1, the more likely the host vehicle 1 is to change lanes at a predetermined driving assistance level.

[0044] Furthermore, the processor 10 of the driving control device 100 may calculate an evaluation value based on the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2 so that an evaluation value corresponding to a second inter-vehicle distance that is shorter than the first inter-vehicle distance is higher than an evaluation value corresponding to a first inter-vehicle distance. This makes it easier for the driving control device 100 to permit the host vehicle 1 to travel at a predetermined driving assistance level the shorter the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2. In other words, when an obstacle X is detected ahead, for example, the host vehicle 1 is more likely to change lanes at a predetermined driving assistance level the shorter the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2.

[0045] Furthermore, the processor 10 of the driving control device 100 may calculate the evaluation value based on the elapsed time since the preceding vehicle 2 was detected ahead of the host vehicle 1 so 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. This makes it easier for the driving control device 100 to permit the host vehicle 1 to travel at a predetermined driving assistance level the shorter the time that has elapsed since the preceding vehicle 2 was detected. In other words, when an obstacle X is detected ahead, for example, the host vehicle 1 is more likely to change lanes at a predetermined driving assistance level the shorter the time that has elapsed since the preceding vehicle 2 was detected.

[0046] Furthermore, when multiple adjacent vehicles 3 are detected, the processor 10 of the driving control device 100 calculates the average vehicle speed of the multiple adjacent vehicles 3 as the vehicle speed of the adjacent vehicle 3. This allows the driving control device 100 to perform driving control of the host vehicle 1 at a driving assistance level that corresponds to the driving environment of the second lane L2, based on the vehicle speeds of the multiple adjacent vehicles 3.

[0047] When the processor 10 of the driving control device 100 is controlling the driving of the host vehicle 1 at a predetermined driving assistance level, it controls the driving of the host vehicle 1 in a hands-off mode that allows the host vehicle 1 to travel with the driver's hands off the steering wheel of the host vehicle 1. As a result, when the driving control device 100 is controlling the driving of the host vehicle 1 at a predetermined driving assistance level, it controls the driving of the host vehicle 1 in the hands-off mode, thereby reducing the driving burden on the driver.

[0048] When the processor 10 of the driving control device 100 is controlling the driving of the vehicle 1 at a predetermined driving assistance level, it controls the driving of the vehicle 1 in an eyes-off mode that allows the vehicle 1 to travel when the driver is not looking ahead. As a result, when the driving control device 100 is controlling the driving of the vehicle 1 at a predetermined driving assistance level, it controls the driving of the vehicle 1 in the eyes-off mode, thereby reducing the driving burden on the driver. [Explanation of symbols]

[0049] 1...Own vehicle 3...Adjacent vehicles 4...Other vehicles behind 100...Operation control device 10...Processor 11...Evaluation value calculation unit 12...Relative speed determination unit 13...Driving condition setting section 15...Vehicle control unit L1...Lane 1 L2: Second lane

Claims

1. A driving control method for controlling driving of a host vehicle using a processor so that the host vehicle avoids an obstacle ahead, comprising: The processor: comparing a vehicle speed of the host vehicle traveling in a first lane with a vehicle speed of an adjacent vehicle traveling in a second lane adjacent to the first lane to determine whether the relative speed of the adjacent vehicle with respect to the host vehicle is equal to or less than a predetermined speed difference threshold; A driving control method that, when the relative speed is equal to or less than the speed difference threshold, relaxes driving conditions for allowing the host vehicle to travel when avoiding the obstacle at a predetermined driving assistance level.

2. The processor: calculating an evaluation value indicating the degree of fulfillment of the driving conditions; selecting a second evaluation threshold value lower than the first evaluation threshold value when the relative speed is higher than the speed difference threshold value; The driving control method according to claim 1 , wherein, when the evaluation value is higher than the evaluation threshold, the host vehicle is permitted to travel at the driving assistance level when avoiding the obstacle.

3. The processor:

3. The driving control method according to claim 2, wherein, when there is another vehicle behind the host vehicle within a predetermined distance behind the host vehicle, a second speed difference threshold lower than the first speed difference threshold when there is no other vehicle behind the host vehicle is selected as the speed difference threshold.

4. The processor:

4. The driving control method according to claim 2, wherein when the adjacent vehicle is traveling ahead of the host vehicle, the vehicle speed of the host vehicle is controlled so that the relative speed of the adjacent vehicle with respect to the host vehicle is equal to or less than the speed difference threshold.

5. A driving control method according to any one of claims 2 to 4, wherein the processor calculates the evaluation value so that the evaluation value corresponding to a second vehicle speed of the vehicle, which is lower than the first vehicle speed, is higher than the evaluation value corresponding to a first vehicle speed of the vehicle.

6. A driving control method as described in any one of claims 2 to 4, wherein the processor calculates the evaluation value based on the inter-vehicle distance between the vehicle and a preceding vehicle traveling in the first lane so 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. A driving control method according to any one of claims 2 to 4, wherein when a preceding vehicle is detected in front of the vehicle in the first lane, the processor calculates the evaluation value so that the evaluation value corresponding to a second elapsed time that is shorter than the first elapsed time is higher than the evaluation value corresponding to a first elapsed time.

8. The processor: The driving control method according to any one of claims 1 to 7, wherein, when a plurality of adjacent vehicles are detected, an average vehicle speed of the plurality of adjacent vehicles is calculated as the vehicle speed of the adjacent vehicle.

9. The driving control method according to any one of claims 1 to 8, wherein, when the driving of the vehicle is controlled at the driving assistance level, the processor controls the driving of the vehicle in a hands-off mode that allows the vehicle to travel when the driver releases their hands from the steering wheel of the vehicle.

10. The driving control method according to any one of claims 1 to 9, wherein, when the driving of the vehicle is controlled at the driving assistance level, the processor controls the driving of the vehicle using an eyes-off mode that allows the vehicle to travel when the driver is not looking ahead.

11. A driving control device that controls driving of a host vehicle using a processor so that the host vehicle avoids an obstacle ahead, The processor: a relative speed determination unit that compares a vehicle speed of the host vehicle traveling in a first lane with a vehicle speed of an adjacent vehicle traveling in a second lane adjacent to the first lane, and determines whether the relative speed of the adjacent vehicle with respect to the host vehicle is equal to or less than a predetermined speed difference threshold; A driving control device comprising: a driving condition setting unit that, when the relative speed is equal to or less than the speed difference threshold, relaxes driving conditions for allowing the host vehicle to travel when avoiding the obstacle at a predetermined driving assistance level.

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