Driving control method and driving control device

Abstract

To suppress the creation of the necessity of an excessive approach of an own vehicle and an on-coming vehicle, and the abrupt deceleration of the own vehicle caused by a delay of the recognition of the on-coming vehicle when avoiding an obstacle existing on an own vehicle lane by protruding to an on-coming vehicle lane following a preceding vehicle.SOLUTION: A controller 18 performs: processing (S1) for detecting an obstacle existing on an own vehicle lane in which an own vehicle travels, and in front of the own vehicle; processing (S2) for creating an avoidance track in which the own vehicle passes a sideway of the obstacle while protruding to an on-coming vehicle lane from the own vehicle lane; processing (S4) for setting a gaze zone on the on-coming vehicle lane and in front of the own vehicle; processing (S8) for increasing an inter-vehicle distance between the own vehicle and a preceding vehicle by decelerating a traveling speed of the own vehicle when the gaze zone of the own vehicle cannot be recognized by the preceding vehicle; and processing (S6) for making the own vehicle travel along the avoidance track when the gaze zone can be recognized by decelerating the traveling speed of the own vehicle.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to a cruise control method and a cruise control device. [Background technology]

[0002] Patent Document 1 proposes a collision prevention device that determines the possibility of a collision between a vehicle that is overtaking an oncoming vehicle and performs a collision prevention operation if the possibility of a collision is equal to or greater than a set value. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-023399 Summary of the Invention [Problem to be solved by the invention]

[0004] When a vehicle avoids an obstacle in its own lane by following a preceding vehicle into the oncoming lane, the driver may be late in recognizing the oncoming vehicle due to a blind spot created by the preceding vehicle. If the driver is late in recognizing the oncoming vehicle, the driver's vehicle may get too close to the oncoming vehicle or may need to suddenly decelerate. To prevent a vehicle from coming too close to an oncoming vehicle or from having to suddenly decelerate its own vehicle due to a delay in recognizing the oncoming vehicle when the vehicle avoids an obstacle in its own lane by following a preceding vehicle into an oncoming lane. [Means for solving the problem]

[0005] In one aspect of the driving control method of the present invention, a controller performs the following processes: detecting an obstacle in the lane in which the vehicle is traveling and in front of the vehicle; generating an avoidance trajectory in which the vehicle extends from the lane into the oncoming lane and passes beside the obstacle; setting a gaze zone in the oncoming lane and in front of the vehicle; slowing down the vehicle to increase the distance between the vehicle and the preceding vehicle when the gaze zone cannot be recognized by the vehicle preceding the vehicle; and driving the vehicle along the avoidance trajectory when the gaze zone can be recognized by slowing down the vehicle. [Effects of the Invention]

[0006] According to the present invention, when an obstacle in one's own lane is avoided by following a preceding vehicle into the oncoming lane, it is possible to prevent the vehicle from coming too close to the oncoming vehicle or the need to suddenly decelerate the vehicle due to a delay in recognizing the oncoming vehicle. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a schematic configuration diagram of an example of a travel control device according to an embodiment; [Figure 2] 1 is a schematic diagram illustrating an example of a situation in which a cruise control method according to an embodiment is executed; [Figure 3] 1 is a schematic diagram illustrating an example of a situation in which a cruise control method according to an embodiment is executed; [Figure 4] FIG. 2 is a block diagram illustrating an example of a functional configuration of a controller. [Figure 5] FIG. 10 is a schematic diagram for explaining an example of a method for generating an avoidance trajectory. [Figure 6] FIG. 2 is a schematic diagram showing an example of an empty space ahead of a leading vehicle. [Figure 7] FIG. 10 is a schematic diagram illustrating an example of a method for calculating a deceleration rate for increasing the inter-vehicle distance from a preceding vehicle. [Figure 8] 10A and 10B are diagrams illustrating an example of a vehicle speed profile when decelerating to increase the distance between the host vehicle and a preceding vehicle, and a vehicle speed profile when stopping the host vehicle. [Figure 9]FIG. 10 is a schematic diagram illustrating an example of a case where it is possible to determine that there is no oncoming vehicle in the fixation zone even if part of the fixation zone cannot be recognized. [Figure 10] 10A and 10B are schematic diagrams showing an example of an avoidance trajectory when only an obstacle is avoided, and an example of an avoidance trajectory when both a preceding vehicle and an obstacle are avoided. [Figure 11] 3 is a flowchart illustrating an example of a driving control method according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the drawings are schematic and may differ from the actual product. Furthermore, the embodiments of the present invention shown below are examples of devices and methods for embodying the technical concept of the present invention, and the technical concept of the present invention does not limit the structure, arrangement, etc. of component parts to those described below. The technical concept of the present invention can be modified in various ways within the technical scope defined by the claims.

[0009] (composition) 1 is a schematic diagram of an example of a cruise control device according to an embodiment. A host vehicle 1 is equipped with a cruise control device 10. The cruise control device 10 controls the cruise of the host vehicle 1. For example, the driving control by the driving control device 10 may be autonomous driving control that causes the vehicle 1 to autonomously drive to a set destination based on the driving environment around the vehicle 1. Furthermore, for example, the driving control by the driving control device 10 may be driving assistance control that assists the driver in driving the vehicle 1 by controlling the acceleration, deceleration, and steering of the vehicle 1.

[0010] For example, the driving assistance control may include lane keeping control, which controls the steering of the vehicle 1 so that the vehicle 1 does not deviate from the driving lane, obstacle avoidance control, which controls the steering of the vehicle 1 so that the vehicle 1 avoids obstacles ahead of the vehicle 1, and leading vehicle following control, which controls the acceleration and deceleration of the vehicle 1 so that the vehicle 1 follows the leading vehicle. In the following explanation, an example will be described in which the driving control by the driving control device 10 is autonomous driving control that causes the host vehicle 1 to autonomously drive to a set destination, and lane keeping control, obstacle avoidance control, and preceding vehicle following control are executed as part of the autonomous driving control. However, the present invention is not limited to this, and can also be applied to a case in which lane keeping control, obstacle avoidance control, and preceding vehicle following control are executed individually without setting a destination.

[0011] The driving control device 10 includes an object sensor 11, a vehicle sensor 12, a positioning device 13, a map database (map DB) 14, a communication device 15, a navigation device 16, an actuator 17, and a controller 18. The object sensor 11 includes a plurality of different types of object detection sensors mounted on the vehicle 1, such as a laser radar, a millimeter wave radar, a camera, and a LIDAR (Light Detection and Ranging, Laser Imaging Detection and Ranging) that detect objects around the vehicle 1. Vehicle sensor 12 is mounted on host vehicle 1 and detects various information (vehicle signals) obtained from host vehicle 1. Vehicle sensor 12 includes, for example, a vehicle speed sensor that detects the vehicle speed of host vehicle 1, a wheel speed sensor that detects the rotational speed of the tires of host vehicle 1, a three-axis acceleration sensor that detects the acceleration and deceleration in three axial directions of host vehicle 1, a steering angle sensor that detects the steering angle of the steering wheel, a turning angle sensor that detects the turning angle of the steered wheels, a gyro sensor that detects the angular velocity of host vehicle 1, a yaw rate sensor that detects the yaw rate, an accelerator sensor that detects the accelerator opening of the host vehicle, and a brake sensor that detects the amount of brake operation by the driver.

[0012] The positioning device 13 includes a Global Navigation System (GNSS) receiver and receives radio waves from multiple navigation satellites to measure the current position of the vehicle 1. The GNSS receiver may be, for example, a Global Positioning System (GPS) receiver. The positioning device 13 may also be, for example, an inertial navigation system. The map database 14 stores road map data. The map database 14 may store map data for navigation (hereinafter, sometimes referred to as "navigation map data") as the road map data. The navigation map data includes information for each road. For example, the navigation map data includes information on road nodes that indicate reference points on road reference lines and information on road links that indicate the section configurations of roads between the road nodes. The road node information includes position coordinates, the number of connected road links, and identification information of the connected road links.

[0013] The map database 14 may store high-precision map data as road map data. High-precision map data is map data suitable as map information for automated driving, and includes more detailed information on a lane-by-lane basis than information on a road-by-road basis. As information for each lane, for example, high-precision map data includes information on lane nodes that indicate reference points on lane reference lines (e.g., the center line within a lane), information on lane links that indicate the section configuration of the lane between lane nodes, and information on lane speed limits. The lane node information includes the position coordinates of the lane node, the number of connected lane links, and the identification information of the connected lane links. The lane link information includes the lane type, lane width, lane boundary line type, lane shape, lane marking shape, and lane reference line shape.

[0014] The communication device 15 performs wireless communication with a communication device outside the vehicle 1. The communication method used by the communication device 15 may be, for example, wireless communication using a public mobile phone network, vehicle-to-vehicle communication, road-to-vehicle communication, or satellite communication. The navigation device 16 recognizes the current position of the vehicle using the positioning device 13 and obtains navigation map data for the current position from the map database 14. The navigation device 16 sets a target driving route to the destination input by the occupant and provides route guidance to the occupant along the target driving route. The navigation device 16 also outputs information about the set target driving route to the controller 18. During autonomous driving control, the controller 18 automatically drives the vehicle 1 so that it travels along the target driving route set by the navigation device 16.

[0015] The actuator 17 operates the steering wheel, accelerator opening, and brake device of the host vehicle in response to control signals from the controller 18 to generate vehicle behavior of the host vehicle. The actuator 17 includes a steering actuator, an accelerator opening actuator, and a brake control actuator. The steering actuator controls the steering direction and steering amount of the steering of the host vehicle. The accelerator opening actuator controls the accelerator opening of the host vehicle. The brake control actuator controls the braking operation of the brake device of the host vehicle.

[0016] The controller 18 is an electronic control unit that controls the running of the host vehicle 1. The controller 18 includes a processor 18a and peripheral components such as a storage device 18b. The processor 18a may be, for example, a CPU or an MPU. The storage device 18b may include a semiconductor storage device, a magnetic storage device, an optical storage device, etc. The storage device 18b may include memories such as a register, a cache memory, and a ROM and a RAM used as a main storage device. The functions of the controller 18 described below are realized by, for example, the processor 18a executing a computer program stored in the storage device 18b. The controller 18 may be formed of dedicated hardware for executing the various information processes described below. For example, the controller 18 may include a functional logic circuit configured in a general-purpose semiconductor integrated circuit. For example, the controller 18 may include a PLD such as an FPGA.

[0017] Next, an example of driving control by the controller 18 will be described. Fig. 2 is a schematic diagram of an example of a situation in which the driving control method of the embodiment is executed. Reference character L1 indicates the lane in which the host vehicle 1 is traveling, and reference character L2 indicates the oncoming lane of the host lane L1. The oncoming lane L2 is provided adjacent to the host lane L1. When the controller 18 detects an obstacle Ob that exists on the own lane L1 and ahead of the own vehicle 1, the controller 18 starts obstacle avoidance control to avoid the obstacle Ob. In the obstacle avoidance control, the controller 18 generates an avoidance trajectory Ta for the own vehicle 1 to travel while avoiding the obstacle Ob. In the example of Fig. 2, the controller 18 generates an avoidance trajectory Ta that extends from the own lane L1 into the oncoming lane L2, passes by the side of the obstacle Ob, and returns to the own lane L1 after passing by the side of the obstacle Ob.

[0018] Symbol Sp indicates the section where the body of vehicle 1 extends into the oncoming lane L2 when vehicle 1 travels along the avoidance trajectory Ta (hereinafter referred to as the "extension section Sp"); symbol Pp1 indicates the start point of the extension section Sp; and symbol Pp2 indicates the end point of the extension section Sp. The controller 18 drives the actuator 17 so that the host vehicle 1 travels along the avoidance trajectory Ta, causing the host vehicle 1 to veer into the oncoming lane L2, pass by the side of the obstacle Ob, and then return to the host vehicle lane L1.

[0019] As shown in FIG. 2, it is assumed that a leading vehicle 2 is traveling ahead of the host vehicle 1, and the leading vehicle 2 also strays into the oncoming lane L2 to avoid an obstacle Ob. The presence of the preceding vehicle 2 causes a blind spot for the object sensor 11. In the following description, the area in which the object sensor 11 cannot recognize the surrounding environment due to the preceding vehicle 2 is referred to as a "blind spot area." The hatched areas in Figures 2, 3, 6, and 9 are blind spot areas Rd. When the host vehicle 1 follows the preceding vehicle 2 to avoid an obstacle Ob, the host vehicle 1 may be late in recognizing the oncoming vehicle 3 due to a blind spot Rd created by the preceding vehicle 2. If the host vehicle 1 is late in recognizing the oncoming vehicle 3, the host vehicle 1 and the oncoming vehicle 3 may become too close to each other, or the host vehicle 1 may need to suddenly decelerate in order to prevent the host vehicle 1 from getting too close to the oncoming vehicle 3.

[0020] Therefore, the controller 18 sets a gaze zone Sg on the oncoming lane L2 and ahead of the host vehicle 1, and determines whether the object sensor 11 can recognize the situation within the gaze zone Sg. When the situation in the gaze section Sg cannot be recognized due to the preceding vehicle 2, the controller 18 decelerates the host vehicle 1 to increase the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2.

[0021] When the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2 increases, the range in which the object sensor 11 cannot detect an object due to the preceding vehicle 2 (for example, the range of the camera's angle of view) becomes smaller. As a result, the blind spot area Rd decreases as shown in Fig. 3. Furthermore, if the preceding vehicle 2 completes avoidance of the obstacle Ob before the host vehicle 1 starts steering control to avoid the obstacle Ob (i.e., passes the side of the obstacle Ob and returns to the host vehicle's lane L1), the range of the oncoming lane L2 that enters the blind spot area Rd decreases further.

[0022] When the object sensor 11 becomes able to recognize the situation within the gaze section Sg, the controller 18 drives the actuator 17 to make the host vehicle 1 travel along the avoidance trajectory Ta, causing the host vehicle 1 to stray into the oncoming lane L2, pass by the side of the obstacle Ob, and then return to the host vehicle lane L1. On the other hand, if the situation within the gaze section Sg cannot be recognized even after decelerating the vehicle 1, the controller 18 sets a stop position Ps on the avoidance trajectory Ta just before the obstacle Ob and drives the actuator 17 to stop the vehicle 1 at the stop position Ps. After the host vehicle 1 has stopped, when the object sensor 11 becomes able to recognize the situation within the gaze section Sg, the controller 18 drives the actuator 17 so that the host vehicle 1 travels along the avoidance trajectory Ta.

[0023] As a result, when avoiding an obstacle Ob on the own lane L1 by drifting into the oncoming lane L2 following the leading vehicle 2, the own vehicle 1 can be prevented from drifting into the oncoming lane L2 until it becomes possible to recognize the situation in the gaze section Sg on the oncoming lane L2. As a result, it is possible to prevent the own vehicle 1 and the oncoming vehicle 3 from getting too close to each other or the need to suddenly decelerate the own vehicle 1 due to a delay in recognition of the oncoming vehicle 3.

[0024] The stop position Ps may be set at a position before the point where the tangent to the avoidance trajectory Ta starts to tilt toward the oncoming lane L2 (i.e., the point where the angle between the tangent to the avoidance trajectory Ta and a line parallel to the extension direction of the oncoming lane L2 becomes larger than 0 degrees and the avoidance trajectory Ta starts to approach the oncoming lane). This prevents the body of the host vehicle 1 from tilting with respect to the traveling direction of the oncoming lane L2 when the host vehicle 1 is stopped at the stop position Ps, making it possible to reduce the range of the gaze section Sg that enters the blind spot area Rd. In addition, in order to reduce the range of the gaze section Sg that falls within the blind spot area Rd, the stop position Ps may be set not on the avoidance trajectory Ta but at a position within the own lane L1 and closer to the oncoming lane L2 than the avoidance trajectory Ta.

[0025] Next, a detailed description will be given of the functions of the controller 18. Figure 4 is a block diagram showing an example of the functional configuration of the controller. The controller 18 includes a target route acquisition unit 30, a road boundary acquisition unit 31, an obstacle recognition unit 32, a preceding vehicle recognition unit 33, a vehicle position acquisition unit 34, a limited vehicle speed acquisition unit 35, an avoidance judgment unit 36, an avoidance plan generation unit 37, a preceding vehicle acquisition unit 38, a gaze section calculation unit 39, an empty section estimation unit 40, a blind spot area calculation unit 41, a deceleration calculation unit 42, a stop / start judgment unit 43, a target vehicle speed setting unit 44, and a vehicle control unit 45.

[0026] The target route acquisition unit 30 acquires a target driving route from the current position of the vehicle 1 to a destination set by the occupant. For example, the target route acquisition unit 30 may acquire information on the target driving route from the navigation device 16. The lane boundary acquisition unit 31 acquires information on the position and shape of lane boundaries of the current lane L1. For example, the lane boundary acquisition unit 31 acquires the position and shape of the lane boundary line between the current lane L1 and an oncoming lane L2 adjacent to the current lane L1. Furthermore, for example, the lane boundary acquisition unit 31 acquires the position and shape of the lane boundary line on the opposite side of the oncoming lane L2 from the lane boundary lines on both the left and right sides of the current lane L1.

[0027] The lane boundary acquisition unit 31 may acquire information on the position and shape of lane boundaries from, for example, an image captured by a camera of the object sensor 11 of the area ahead of the vehicle 1. Alternatively, for example, the lane boundary information may be acquired based on the current position of the vehicle 1 acquired by a vehicle position acquisition unit 34 (described later) and high-precision map data in the map database 14. The obstacle recognition unit 32 recognizes obstacles present around the host vehicle 1 based on the captured image output by the camera of the object sensor 11 and the detection signals output from other sensors of the object sensor 11 .

[0028] The preceding vehicle recognition unit 33 recognizes the preceding vehicle 2 traveling ahead of the host vehicle 1 based on the captured image output by the camera of the object sensor 11 and the detection signals output from other sensors of the object sensor 11. The vehicle position acquisition unit 34 acquires the current position information of the vehicle 1 measured by the positioning device 13 . The vehicle speed limit acquisition unit 35 acquires vehicle speed limit information related to the vehicle speed limit vmax of the oncoming lane L2. For example, the vehicle speed limit information of the oncoming lane L2 may be read from high-precision map data in the map database 14 based on the current position information of the host vehicle 1 measured by the positioning device 13. Alternatively, for example, a vehicle speed limit sign specifying the vehicle speed limit for the host lane L1 may be recognized from an image captured by the camera of the object sensor 11, and the vehicle speed limit for the host lane L1 may be estimated to be the vehicle speed limit vmax for the oncoming lane L2.

[0029] The avoidance judgment unit 36 ​​judges whether or not an obstacle Ob exists on the lane L1 on which the vehicle 1 is traveling and ahead of the vehicle 1, based on the target driving route acquired by the target route acquisition unit 30, information on the lane boundary of the vehicle L1 acquired by the lane boundary acquisition unit 31, and information on obstacles recognized by the obstacle recognition unit 32. When an obstacle Ob exists, the avoidance determination unit 36 ​​determines to start obstacle avoidance control.

[0030] When obstacle avoidance control begins, the avoidance plan generation unit 37 generates an avoidance trajectory Ta along which the host vehicle 1 travels to avoid the obstacle Ob, and a target vehicle speed plan which is a plan of the speed at which the host vehicle 1 will travel along the avoidance trajectory Ta. The avoidance plan generating unit 37 includes a trajectory planning unit 37a that generates an avoidance trajectory Ta, and a vehicle speed planning unit 37b that generates a target vehicle speed plan.

[0031] Fig. 5 is a schematic diagram illustrating an example of a method for generating an avoidance trajectory Ta. The trajectory planning unit 37a determines the direction in which the host vehicle 1 moves laterally to avoid the obstacle Ob (hereinafter referred to as the "avoidance direction Da"). Then, the lane boundary B1, which is the boundary of the range in which the host vehicle 1's lane is set, is expanded to include an adjacent lane adjacent to the avoidance direction Da (the oncoming lane L2 in the example of Fig. 5). The trajectory planning unit 37a generates a candidate avoidance trajectory T1 that passes through the lane width center position of the lane boundary B1.

[0032] Next, the trajectory planning unit 37a sets a no-entry area around the obstacle Ob, and determines whether there is a gap in the lane width direction that is equal to or greater than a predetermined margin mrg between the boundary B2 of the no-entry area and the avoidance trajectory candidate T1. If there is a gap in the lane width direction that is equal to or greater than the predetermined margin mrg, the trajectory planning unit 37a sets the avoidance trajectory candidate T1 as the avoidance trajectory Ta. If there is no gap in the lane width direction greater than a predetermined margin mrg between the boundary B2 of the no-entry area and the avoidance trajectory candidate T1, the trajectory T2 obtained by offsetting the boundary B2 by the predetermined margin mrg is set as the avoidance trajectory Ta.

[0033] See Fig. 4. The trajectory planning unit 37a sets the stop position Ps at a position before the point where the tangent to the generated avoidance trajectory Ta starts to incline toward the oncoming lane L2. The preceding vehicle acquisition unit 38 acquires information about the preceding vehicle 2 based on the recognition result of the preceding vehicle 2 by the preceding vehicle recognition unit 33. The preceding vehicle acquisition unit 38 includes a preceding vehicle position acquisition unit 38a that acquires the position of the preceding vehicle 2, and a preceding vehicle speed acquisition unit 38b that acquires the vehicle speed of the preceding vehicle 2. The gaze section calculation unit 39 calculates the gaze section Sg on the oncoming lane L2 based on the limit vehicle speed vmax of the oncoming lane L2 acquired by the limit vehicle speed acquisition unit 35, the avoidance trajectory Ta generated by the avoidance plan generation unit 37, and the stopping position Ps.

[0034] See Figure 2. In the following description, the extension direction of the oncoming lane L2 will be simply referred to as the "extension direction." First, the gaze section calculation unit 39 sets the stop position Ps as the position of the near end of the gaze section Sg in the extension direction (the end closest to the host vehicle 1). Next, the gaze section calculation unit 39 calculates the time t1 required for the vehicle 1 to travel from the stop position Ps to the end point Pp2 of the protrusion section Sp according to the following equation (1). t1=(x2-x1) / v1 …(1) The variables x1 and x2 are the positions of the stop position Ps and the end point Pp2 in the extension direction, respectively. The variable v1 is the current vehicle speed of the host vehicle 1. The gaze section calculation unit 39 calculates the distance from the end point Pp2 to the position x3 of the far end (the end farthest from the host vehicle 1) of the gaze section Sg in the extension direction according to the following equation (2). Distance from the end point Pp2 to the far end x3 of the gaze section Sg = vmax × t1 ... (2)

[0035] 4, the vacant section estimation unit 40 estimates a vacant section Sf, which is a section on the oncoming lane L2 where no oncoming vehicle 3 exists ahead of the rear end of the leading vehicle 2, based on the position information and vehicle speed information of the leading vehicle 2 acquired by the leading vehicle acquisition unit 38. See Fig. 6. The empty section estimation unit 40 estimates the rear end position of the leading vehicle 2 as the position of the near end of the empty section Sf in the extension direction. The empty section estimation unit 40 selects the section length xpred of the empty section Sf according to the following equation (3). xpred=v2 2 / dmax1 …(3) The variable v2 is the current speed of the preceding vehicle 2, and the constant dmax1 is the set value of the upper limit value allowed as the deceleration of the preceding vehicle 2.

[0036] 4, the blind spot area calculation unit 41 calculates a blind spot area Rd where the object sensor 11 cannot recognize the surrounding environment due to the preceding vehicle 2, based on the position information of the preceding vehicle 2 acquired by the preceding vehicle acquisition unit 38, the current position of the host vehicle 1 acquired by the host vehicle position acquisition unit 34, and the known detection range of the object sensor 11. The deceleration calculation unit 42 calculates the deceleration d1 used when decelerating the host vehicle 1 to increase the inter-vehicle distance between the host vehicle 1 and the preceding vehicle 2. For example, the deceleration d1 is set so that the preceding vehicle 2 completes avoidance of the obstacle Ob (i.e., passes by the side of the obstacle Ob) and returns to the host vehicle lane L1 by the time the host vehicle 1 reaches the stop position Ps or before that.

[0037] An example of calculation of the deceleration d1 will be described with reference to Fig. 7. The deceleration calculation unit 42 calculates the time t2 required for the preceding vehicle 2 to complete avoidance of the obstacle Ob according to the following equation (4). t2=(x2-x4) / v2 …(4) The variable x4 is the current position of the leading vehicle 2 in the extension direction. 4, the deceleration calculation unit 42 calculates the deceleration d1 according to the following equation (5) based on the current vehicle speed v1 of the host vehicle 1, the current position of the host vehicle 1, the stop position Ps, and the time t2 required for the leading vehicle 2 to complete avoiding the obstacle Ob. x1-x5=v1×t2+(1 / 2)×d1×t2 2 …(5) The variable x5 is the current position of the vehicle 1 in the extension direction. However, the deceleration calculation unit 42 limits the deceleration d1 so that it does not exceed the upper limit value dmax2 that is permissible as the deceleration of the host vehicle 1.

[0038] The stop / start determination unit 43 determines whether or not to stop the host vehicle 1 at the stop position Ps based on the gaze section Sg calculated by the gaze section calculation unit 39, the vacant section Sf estimated by the vacant section estimation unit 40, and the blind spot area Rd calculated by the blind spot area calculation unit 41. After the host vehicle 1 has stopped at the stop position Ps, the stop / start determination unit 43 determines whether or not to start the host vehicle 1 from the stop position Ps based on the gaze section Sg, the vacant section Sf, and the blind spot area Rd.

[0039] Specifically, the stop / start determination unit 43 determines that the situation within the fixation section Sg can be recognized when the fixation section Sg and the blind spot area Rd do not overlap at all. In this case, the stop / start determination unit 43 determines not to decelerate the host vehicle 1 at the deceleration d1 and not to stop the host vehicle 1 at the stop position Ps. On the other hand, if a part or all of the gaze section Sg overlaps with the blind spot area Rd, the stop / start determination unit 43 determines that the situation within the gaze section Sg cannot be recognized. In this case, the stop / start determination unit 43 determines that, in principle, the host vehicle 1 is to be decelerated at a deceleration d1.

[0040] Furthermore, if it is determined that the situation within the gaze section Sg cannot be recognized even though the vehicle 1 has decelerated at the deceleration d1 calculated by the deceleration calculation unit 42, it is decided to stop the vehicle 1 at the stop position Ps. For example, if the stop / start judgment unit 43 determines that the situation within the gaze section Sg cannot be recognized even when the vehicle 1 reaches the stop control start position xc where the vehicle 1 can decelerate at a deceleration d2 (>d1) and stop at the stop position Ps, the stop / start judgment unit 43 may decide to stop the vehicle 1 at the stop position Ps as a general rule.

[0041] Figure 8 shows an example of a vehicle speed profile Prd when decelerating at a deceleration rate d1 to increase the distance between the host vehicle 1 and the preceding vehicle 2, and a vehicle speed profile Prs when decelerating the host vehicle 1 at a deceleration rate d2 to stop it at a stop position Ps. For example, the stop / start determination unit 43 calculates the point where the vehicle speed profile Prd and the vehicle speed profile Prs intersect as the stop control start position xc based on the vehicle speed of the host vehicle 1. The stop / start determination unit 43 may determine to decelerate the host vehicle 1 at a deceleration d1 until the host vehicle 1 reaches the stop control start position xc. If it is determined that the situation within the gaze section Sg cannot be recognized even when the vehicle 1 reaches the stop control start position xc, it may be determined that the situation within the gaze section Sg cannot be recognized despite deceleration, and it may be decided that, in principle, the vehicle 1 should be stopped at the stop position Ps.

[0042] However, even if the object sensor 11 cannot recognize the situation in part of the gaze section Sg because part of the gaze section Sg overlaps with the blind spot area Rd, the stop / start judgment unit 43 may decide not to decelerate the vehicle 1 at the deceleration d1 and not to stop the vehicle 1 at the stop position Ps if it can determine that there is no oncoming vehicle 3 in the gaze section Sg. 9 is a schematic diagram of an example of a case where it is possible to determine that there is no oncoming vehicle 3 in the gaze section Sg even if part of the gaze section Sg cannot be recognized. For example, even if part of the gaze section Sg and the blind spot area Rd overlap in the section Sg1, the stop / start determination unit 43 may determine that there is no oncoming vehicle 3 in the gaze section Sg if it can recognize a range that is half or more of the lane width of the oncoming lane L2 over the entire length of the section Sg1.

[0043] Further, for example, the stop / start determination unit 43 may store information on the situation in the gaze section Sg recognized by the object sensor 11 in the storage device 18b before the gaze section Sg overlaps with the blind spot area Rd, and determine whether or not there is an oncoming vehicle 3 in the gaze section Sg based on the stored information. Furthermore, the stop / start determination unit 43 may determine whether or not there is an oncoming vehicle 3 in the gaze section Sg based on vehicle-to-vehicle communication or road-to-vehicle communication by the communication device 15.

[0044] 6, the stop / start determination unit 43 determines whether the section where the gaze section Sg and the blind spot area Rd overlap is covered by the empty section Sf. That is, it determines whether the entire section where the gaze section Sg and the blind spot area Rd overlap is included in the empty section Sf. When the section where the gaze section Sg and the blind spot area Rd overlap is covered by the empty section Sf, the stop / start judgment unit 43 decides not to decelerate the vehicle 1 at the deceleration d1 and not to stop the vehicle at the stop position Ps.

[0045] Furthermore, if the stop / start determination unit 43 determines that the situation within the gaze section Sg can be recognized after the host vehicle 1 has stopped at the stop position Ps, it decides to start the host vehicle 1 from the stop position Ps.

[0046] The target vehicle speed setting unit 44 sets the target vehicle speed of the host vehicle 1 based on the target vehicle speed plan generated by the avoidance plan generation unit 37, the deceleration d1 set by the deceleration calculation unit 42, and the judgment result of the stop / start judgment unit 43. Specifically, when the stop / start determination unit 43 determines that the host vehicle 1 will not be decelerated at the deceleration rate d1 and will not be stopped at the stop position Ps, the target vehicle speed setting unit 44 determines the target vehicle speed of the host vehicle 1 based on the target vehicle speed plan generated by the avoidance plan generation unit 37. That is, the target vehicle speed of the host vehicle 1 is set so that the host vehicle 1 travels along the avoidance trajectory Ta without decelerating at the deceleration rate d1. The same applies when the stop / start determination unit 43 determines that the host vehicle 1 will be started from the stop position Ps.

[0047] Furthermore, when the stop / start determination unit 43 determines to decelerate the host vehicle 1 at the deceleration d1, the target vehicle speed setting unit 44 sets the target vehicle speed so that the host vehicle 1 decelerates at the deceleration d1 set by the deceleration calculation unit 42. When the stop / start determination unit 43 determines to stop the host vehicle 1 at the stop position Ps, the target vehicle speed setting unit 44 sets the target vehicle speed so that the host vehicle 1 decelerates at the deceleration d2 and stops at the stop position Ps. See Fig. 8. When the stop / start determination unit 43 determines that the host vehicle 1 is to be stopped at the stop position Ps, the target vehicle speed changes according to the vehicle speed profile Prd until the host vehicle 1 reaches the stop control start position xc. When the host vehicle 1 reaches the stop control start position xc, the deceleration switches from d1 to d2, and the target vehicle speed changes according to the vehicle speed profile Prs.

[0048] See Fig. 4. The vehicle control unit 45 drives the actuator 17 so that the host vehicle 1 travels on the avoidance trajectory Ta generated by the avoidance plan generation unit 37 at the target vehicle speed set by the target vehicle speed setting unit 44. When an obstacle Ob is detected during execution of the control for following the preceding vehicle 2, the controller 18 may stop the control for following the preceding vehicle 2 and start the obstacle avoidance control described above. This makes it possible to avoid accelerating by following the preceding vehicle 2 when the preceding vehicle 2 cannot recognize the situation in the gaze section Sg.

[0049] Furthermore, when the preceding vehicle 2 stops in front of an obstacle Ob, the avoidance plan generating unit 37 may determine whether the preceding vehicle is an avoidance target. For example, when the preceding vehicle 2 stops temporarily and the stopped state does not continue, the avoidance plan generating unit 37 may determine that the preceding vehicle is not an avoidance target. For example, the avoidance plan generating unit 37 may determine whether the preceding vehicle 2 is an avoidance target based on the stopping position of the preceding vehicle 2 in the lane width direction of the own lane L1. For example, if the distance between the shoulder of the own lane L1 and the preceding vehicle 2 is equal to or greater than a threshold, the avoidance plan generating unit 37 may determine that the preceding vehicle 2 is not an avoidance target.

[0050] For example, if the stopped leading vehicle 2 has its turn signal on for the oncoming lane L2, it can be assumed that the leading vehicle 2 is waiting in front of the obstacle Ob to pass the oncoming vehicle 3, and therefore it may be determined that the leading vehicle 2 is not a target to be avoided. For example, if the stopped leading vehicle 2 has its hazard lamps (emergency flashers) on, it can be assumed that the leading vehicle 2 will remain stopped, and therefore it may be determined that the leading vehicle 2 is a target to be avoided. If the avoidance plan generating unit 37 determines that the preceding vehicle 2 is not an avoidance target, it may generate an avoidance trajectory that avoids only the obstacle Ob. If the avoidance plan generating unit 37 determines that the preceding vehicle 2 is an avoidance target, it may generate an avoidance trajectory that avoids both the obstacle Ob and the preceding vehicle 2. Referring to Fig. 10, the symbol Ta indicates an example of an avoidance trajectory in which the host vehicle 1 strays into the oncoming lane L2 and passes only over the obstacle Ob, and the symbol Ta2 indicates an example of an avoidance trajectory in which the host vehicle 1 strays into the oncoming lane L2 and passes beside both the leading vehicle 2 and the obstacle Ob.

[0051] (operation) FIG. 11 is a flowchart of an example of a driving control method according to an embodiment. In step S1, the avoidance plan generation unit 37 determines whether or not the avoidance determination unit 36 ​​has started obstacle avoidance control. If obstacle avoidance control has been started (step S1: Y), the process proceeds to step S2. If obstacle avoidance control has not been started (step S1: N), the process returns to step S1. In step S2, the avoidance plan generating unit 37 generates an avoidance trajectory Ta.

[0052] In step S3, the avoidance plan generating unit 37 sets a stop position Ps. In step S4, the gaze section calculation unit 39 sets a gaze section Sg ahead of the host vehicle 1 on the oncoming lane L2. In step S5, the stop / start determination unit 43 determines whether the situation within the gaze section Sg can be recognized by the object sensor 11. If the situation within the gaze section Sg can be recognized (step S5: Y), the process proceeds to step S6. If the situation within the gaze section Sg cannot be recognized (step S5: N), the process proceeds to step S7.

[0053] In step S6, the stop / start determination unit 43 determines not to decelerate the host vehicle 1 at the deceleration d1 and not to stop the host vehicle 1 at the stop position Ps. Alternatively, if the host vehicle 1 is waiting at the stop position Ps, it determines to start the host vehicle 1. The target vehicle speed setting unit 44 determines the target vehicle speed of the host vehicle 1 based on the target vehicle speed plan generated by the avoidance plan generation unit 37. The vehicle control unit 45 drives the actuator 17 so that the host vehicle 1 travels on the avoidance trajectory Ta at the target vehicle speed set by the target vehicle speed setting unit 44. The processing then ends.

[0054] In step S7, the stop / start determination unit 43 determines whether the section where the gaze section Sg and the blind spot area Rd overlap is covered by the empty section Sf. If it is covered by the empty section Sf (step S7: Y), the process proceeds to step S6. If it is not covered by the empty section Sf (step S6: N), the process proceeds to step S8. In step S8, the stop / start determining unit 43 determines whether or not the object sensor 11 has become able to recognize the situation within the gaze section Sg after the host vehicle 1 has been decelerated at the deceleration d1.

[0055] If the situation within the gaze section Sg can be recognized (step S8: Y), the process proceeds to step S6. If the situation within the gaze section Sg cannot be recognized (step S8: N), the process proceeds to step S9. In step S9, the stop / start determination unit 43 determines to stop the host vehicle 1 at the stop position Ps. The vehicle control unit 45 decelerates the host vehicle 1 at a deceleration d2 and stops the host vehicle 1 at the stop position Ps. Thereafter, the process returns to step S5.

[0056] (Effects of the embodiment) (1) The controller 18 performs the following processes: detecting an obstacle present in the lane in which the vehicle 1 is traveling and in front of the vehicle 1; generating an avoidance trajectory in which the vehicle 1 deviates from the lane into the oncoming lane and passes by the side of the obstacle; setting a gaze area in the oncoming lane and in front of the vehicle 1; slowing down the vehicle 1 to increase the distance between the vehicle 1 and the preceding vehicle when the gaze area cannot be recognized by the vehicle preceding the vehicle 1; and driving the vehicle 1 along the avoidance trajectory when the gaze area can be recognized by slowing down the vehicle 1. This prevents the vehicle 1 from coming too close to an oncoming vehicle or from having to suddenly decelerate due to a delay in recognizing the oncoming vehicle, even if the vehicle 1 is not stopped, when the vehicle avoids an obstacle on the vehicle's own lane by following the preceding vehicle into the oncoming lane.

[0057] (2) When the controller 18 cannot recognize the gaze section even after decelerating the host vehicle 1, the controller 18 may stop the host vehicle 1 at a stop position in front of the obstacle. This prevents the vehicle 1 from coming too close to the oncoming vehicle or from having to suddenly decelerate due to a delay in recognizing the oncoming vehicle when avoiding an obstacle on the vehicle's own lane by following the preceding vehicle into the oncoming lane. (3) The controller 18 may set the stop position to a position before the point where the tangent direction of the avoidance trajectory starts to incline toward the oncoming lane. This prevents the body of the vehicle 1 from tilting in the direction of travel in the oncoming lane when the vehicle 1 is stopped at a stop position, thereby reducing the range of the gaze zone that falls in the blind spot of the preceding vehicle.

[0058] (4) The controller 18 may set the stopping position within the own lane and closer to the oncoming lane than the avoidance trajectory. In this way, stopping the vehicle closer to the oncoming lane can reduce the range of the gaze zone that falls in the blind spot of the leading vehicle. (5) The controller 18 may set the length of the watch section based on the time that the host vehicle 1 strays into the oncoming lane when traveling at the speed limit along the avoidance trajectory. This makes it possible to prevent the host vehicle 1 from approaching an oncoming vehicle while traveling in an oncoming lane.

[0059] (6) The controller 18 may perform the following processes: based on the vehicle speed of the preceding vehicle, estimate an empty section in the oncoming lane where there is no oncoming vehicle ahead of the preceding vehicle; determine whether a blind spot area where the preceding vehicle cannot recognize the gaze area is covered by an empty section; and, if the blind spot area is covered by an empty section, drive the host vehicle 1 along an avoidance trajectory. This allows the system to assume that there are no oncoming vehicles even if part of the gaze area is a blind spot, allowing the system to start avoiding obstacles quickly.

[0060] (7) The controller 18 may execute a process to make the vehicle 1 travel along an avoidance trajectory when it can determine that there is no oncoming vehicle in the gaze section, even if part of the gaze section cannot be recognized due to a preceding vehicle. This allows the system to start obstacle avoidance early if it can be determined that there are no oncoming vehicles even if part of the gaze area is in a blind spot. (8) When an obstacle is detected during execution of control to follow a preceding vehicle, controller 18 may stop the control to follow a preceding vehicle. This makes it possible to avoid accelerating to follow a preceding vehicle when the situation in the observation section cannot be recognized due to the preceding vehicle.

[0061] (9) When the preceding vehicle stops in front of an obstacle, the controller 18 may determine whether the preceding vehicle is a target for avoidance, and if it determines that the preceding vehicle is not a target for avoidance, may prohibit the host vehicle 1 from generating an avoidance trajectory that would cause the host vehicle 1 to veer into the oncoming lane and pass beside the preceding vehicle. This makes it possible to prevent the host vehicle 1 from approaching the preceding vehicle that has started to avoid the obstacle. [Explanation of symbols]

[0062] 1...own vehicle, 10...cruising control device, 11...object sensor, 12...vehicle sensor, 13...positioning device, 14...map database, 15...communication device, 16...navigation device, 17...actuator, 18...controller, 18a...processor, 18b...storage device, 30...target route acquisition unit, 31...road boundary acquisition unit, 32...obstacle recognition unit, 33...preceding vehicle recognition unit, 34...own vehicle position acquisition unit, 35...vehicle speed limit acquisition unit, 36...avoidance judgment unit, 37...avoidance plan generation unit, 37a...trajectory planning unit, 37b...vehicle speed planning unit, 38...preceding vehicle acquisition unit, 38a...preceding vehicle position acquisition unit, 38b...preceding vehicle speed acquisition unit, 39...gazing section calculation unit, 40...vacant section estimation unit, 41...blind spot area calculation unit, 42...deceleration calculation unit, 43...stop / start judgment unit, 44...target vehicle speed setting unit, 45...vehicle control unit

Claims

1. A process of detecting an obstacle present in a lane in which the host vehicle is traveling and ahead of the host vehicle; A process of generating an avoidance trajectory in which the host vehicle protrudes from the host lane into an oncoming lane and passes to the side of the obstacle; A process of setting a gaze zone on the oncoming lane and ahead of the host vehicle; a process of decelerating the host vehicle to increase the inter-vehicle distance between the host vehicle and the preceding vehicle when the gaze section cannot be recognized due to a vehicle preceding the host vehicle; a process of causing the host vehicle to travel along the avoidance trajectory when the host vehicle is able to recognize the gaze section by decelerating the host vehicle; A driving control method characterized by causing a controller to execute the above.

2. The driving control method according to claim 1, wherein the controller stops the host vehicle at a stopping position in front of the obstacle when the host vehicle cannot recognize the gaze section even after decelerating the host vehicle.

3. 3. The cruise control method according to claim 2, wherein the controller sets the stop position to a position before a point where a tangent direction of the avoidance trajectory starts to incline toward the oncoming lane.

4. 3. The cruise control method according to claim 2, wherein the controller sets the stop position within the own lane and at a position closer to the oncoming lane than the avoidance trajectory.

5. The driving control method according to any one of claims 1 to 4, characterized in that the controller sets the length of the gaze section based on the time that the vehicle strays into the oncoming lane when traveling at the limited vehicle speed along the avoidance trajectory.

6. The controller a process of estimating an empty section on the oncoming lane where no oncoming vehicle exists ahead of the leading vehicle based on a vehicle speed of the leading vehicle; a process of determining whether a blind spot area where the preceding vehicle cannot recognize the fixation section is covered by the vacant section; a process of causing the host vehicle to travel along the avoidance trajectory when the blind spot area is covered by the open section; 6. The method for controlling driving according to claim 1, further comprising the steps of:

7. The driving control method according to any one of claims 1 to 6, characterized in that the controller causes the vehicle to travel along the avoidance trajectory when it can be determined that there is no oncoming vehicle in the gaze section, even if the preceding vehicle cannot recognize part of the gaze section.

8. The cruise control method according to any one of claims 1 to 7, characterized in that the controller stops the control to follow the preceding vehicle when the obstacle is detected while the control to follow the preceding vehicle is being executed.

9. The cruise control method according to any one of claims 1 to 8, characterized in that, when the preceding vehicle stops in front of the obstacle, the controller determines whether the preceding vehicle is an avoidance target, and, when it is determined that the preceding vehicle is not an avoidance target, does not generate an avoidance trajectory in which the host vehicle strays into the oncoming lane and passes beside the preceding vehicle.

10. A driving control device characterized by comprising a controller that executes the following processes: a process of detecting an obstacle present in the lane in which the vehicle is traveling and in front of the vehicle; a process of generating an avoidance trajectory in which the vehicle deviates from the vehicle's lane into an oncoming lane and passes beside the obstacle; a process of setting a gaze zone in the oncoming lane and in front of the vehicle; a process of slowing down the vehicle to increase the inter-vehicle distance between the vehicle and the preceding vehicle when the gaze zone cannot be recognized by a vehicle preceding the vehicle; and a process of driving the vehicle along the avoidance trajectory when the gaze zone can be recognized by slowing down the vehicle.

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