JP7471900B2 - Vehicle driving support method and driving support device - Google Patents

Description

The present invention relates to a vehicle driving assistance method and driving assistance device.

A driving assistance device is known that, while assisting the host vehicle in changing lanes from a first lane to a second lane, monitors in real time the time required for the host vehicle to catch up with a vehicle ahead of the host vehicle that is traveling in the second lane, and when the required time falls below a predetermined threshold, recalculates the target trajectory when the host vehicle changes lanes so that the final destination point of the target trajectory moves backward along the traveling direction of the host vehicle (Patent Document 1).

JP 2014-61792 A

However, in the above conventional technology, the target trajectory is corrected during a lane change, which can cause the vehicle's behavior to become unstable, especially when the vehicle ahead is traveling at a low speed, or the vehicle may stop while straddling lanes because it is unable to secure the distance required to change lanes.

The problem that this invention aims to solve is to provide a vehicle driving assistance method and device that can stabilize the behavior of the vehicle when changing lanes.

In the present invention, when autonomously controlling a lane change from the own lane to an adjacent lane, first, when a first preceding vehicle traveling on an adjacent lane is detected in front of the own vehicle, a first estimated stop position is calculated as a stop position when it is estimated that the first preceding vehicle will decelerate and stop before autonomous control of the lane change is started. Next, using the first estimated stop position, a first area on the own lane and the adjacent lane in which the own vehicle can travel to change lanes to the adjacent lane behind the first preceding vehicle is calculated, and a position where the lane change is completed within the first area is set as a first lane change completion position. Then, a first trajectory is generated as a travel trajectory for completing the lane change by the first lane change completion position, and after generating the first trajectory, autonomous control of the lane change along the first trajectory is started.

Furthermore, in the present invention, after starting autonomous control of lane changing along the first trajectory, a first stop position which is the stop position of the first preceding vehicle is detected, and the first stop position is used to determine whether the host vehicle will complete the lane change at the first lane change completion position.If it is determined that the lane change will not be completed at the first lane change completion position, the first stop position is used to calculate the position where the host vehicle will stop, and the first trajectory is corrected so that the host vehicle will be able to enter the adjacent lane at the position where the host vehicle will stop, thereby solving the above problem.

The present invention makes it possible to stabilize the vehicle's behavior when changing lanes.

1 is a block diagram showing a driving assistance system including a vehicle driving assistance method and a driving assistance device according to the present invention; 4 is a flowchart showing an information processing procedure in the driving assistance system of FIG. 1 . FIG. 3A is a plan view (part 1) showing an example of a driving scene in which autonomous control of driving operation is performed by the first embodiment of the driving assistance system shown in FIG. 1 . FIG. 3B is a plan view (part 2) showing an example of a driving scene in which autonomous control of driving operation is performed by the first embodiment of the driving assistance system shown in FIG. 1 . FIG. 4A is a plan view (part 1) showing another example of a driving scene in which autonomous control of driving operation is performed by the first embodiment of the driving assistance system shown in FIG. 1 . FIG. 4B is a plan view (part 2) showing another example of a driving scene in which autonomous control of driving operation is performed by the first embodiment of the driving assistance system shown in FIG. 1 . FIG. 5 is a flowchart showing an example of a subroutine of step S6 shown in FIG. 2 according to the first embodiment. FIG. 6 is a flowchart showing an example of a subroutine of step S7 shown in FIG. 2 according to the first embodiment. FIG. 7 is a flowchart showing another example of the subroutine of step S7 shown in FIG. 2 according to the first embodiment. FIG. 8A is a plan view (part 1) showing an example of a driving scene in which autonomous control of driving operation is performed by the second embodiment of the driving assistance system shown in FIG. 1 . FIG. 8B is a plan view (part 2) showing an example of a driving scene in which autonomous control of driving operation is performed by the second embodiment of the driving assistance system shown in FIG. 1 . FIG. 9 is a flowchart showing an example of a subroutine of step S6 shown in FIG. 2 according to the second embodiment. FIG. 10 is a flowchart showing an example of a subroutine of step S7 shown in FIG. 2 according to the second embodiment. FIG. 11A is a plan view (part 1) showing an example of a driving scene in which autonomous control of driving operation is performed by a driving assistance system according to a comparative example of the present invention. FIG. 11B is a plan view (part 2) showing an example of a driving scene in which autonomous control of driving operation is performed by a driving assistance system according to a comparative example of the present invention. FIG. 11C is a plan view (part 3) showing an example of a driving scene in which autonomous control of driving operation is performed by a driving assistance system according to a comparative example of the present invention.

The following describes an embodiment of the present invention with reference to the drawings.

The vehicle driving support method and vehicle driving support device according to the present invention can be applied to autonomous driving control that autonomously executes vehicle speed control and vehicle steering control, and can also be applied to a navigation system that presents an appropriate driving route when the driver is driving manually to support the driver's manual driving. When applied to autonomous vehicle driving control, it can be applied to cases where both speed control and steering control are autonomously controlled, or where one of speed control and steering control is autonomously controlled and the other is manually controlled. An example of applying the vehicle driving support method and vehicle driving support device according to the present invention to a vehicle equipped with an autonomous driving control function is described below.

The following explanation of the embodiment is based on the assumption that in countries with left-hand traffic regulations, vehicles drive on the left side of the road. In countries with right-hand traffic regulations, vehicles drive on the right side of the road, so the right and left in the following explanation should be interpreted as symmetrical.

Figure 1 is a block diagram showing the configuration of a driving assistance system 1000. The driving assistance system 1000 of this embodiment includes a driving assistance device 100 and a vehicle control device 200. The driving assistance device 100 of this embodiment includes a communication device 111, and the vehicle control device 200 also includes a communication device 211. The driving assistance device 100 and the vehicle control device 200 exchange information with each other via wired communication or wireless communication.

More specifically, the driving assistance system 1000 of this embodiment includes a detection device 1, a navigation device 2, map information 3 stored in a readable recording medium, a vehicle information detection device 4, an environment recognition device 5, an object recognition device 6, a driving assistance device 100, and a vehicle control device 200. As shown in FIG. 1, the detection device 1, the navigation device 2, the map information 3 stored in a readable recording medium, the vehicle information detection device 4, the environment recognition device 5, the object recognition device 6, and the driving assistance device 100 are connected to each other by a CAN (Controller Area Network) or other in-vehicle LAN to exchange information with each other.

The detection device 1 of this embodiment detects information about the driving environment including the presence of obstacles located around the host vehicle, such as the entire periphery in front of, to the sides of, and behind the host vehicle, and other conditions around the host vehicle. The detection device 1 of this embodiment includes an imaging device for recognizing environmental information around the host vehicle, such as a camera equipped with an imaging element such as a CCD, an ultrasonic camera, or an infrared camera. The imaging device of this embodiment is installed on the host vehicle, captures images of the surroundings of the host vehicle, and obtains image data including target vehicles that are present around the host vehicle.

The detection device 1 of this embodiment includes a distance measuring device, which calculates the relative distance and relative speed between the vehicle and an object. Information on the object detected by the distance measuring device is output to the processor 10. The distance measuring device may be a type known at the time of filing, such as a laser radar, a millimeter wave radar (LRF, etc.), a LiDAR (light detection and ranging) unit, or an ultrasonic radar.

The detection device 1 of this embodiment can employ one or more imaging devices and a distance measuring device. The detection device 1 of this embodiment has a sensor fusion function that integrates or synthesizes information from multiple different devices, such as detection information from the imaging device and detection information from the distance measuring device, to supplement information that is missing in the detection information and generate environmental information around the vehicle. This sensor fusion function may be incorporated into the environment recognition device 5, object recognition device 6, or other controllers or logic.

The objects detected by the detection device 1 include lane boundaries, center lines, road markings, medians, guardrails, curbs, side walls of expressways, road signs, traffic lights, crosswalks, construction sites, accident sites, and traffic restrictions. The objects detected by the detection device 1 include automobiles (other vehicles) other than the host vehicle, motorcycles, bicycles, and pedestrians. The objects detected by the detection device 1 include obstacles. Obstacles are objects that may affect the running of the host vehicle. The detection device 1 detects at least information about obstacles. The position information of the object detected by the detection device 1 can be detected based on self-position information, such as GPS, which is the position where the host vehicle is running, and the relative position (distance and direction) between the host vehicle and the object. The object detected by the detection device 1 can also be detected by correlating the position information of the object with map information based on map information, self-position information, which is the position where the host vehicle is running using odometry, and the relative position (distance and direction) between the host vehicle and the object.

The navigation device 2 of this embodiment refers to map information 3 and calculates the driving lane/driving route from the current position detected by the vehicle information detection device 4 to the destination. The driving lane or driving route is a linear diagram that identifies the road, direction (uphill/downhill) and lane on which the vehicle is traveling. The driving route includes information about the driving lane. Hereinafter, the driving lane may be abbreviated to lane.

The map information 3 of this embodiment is stored in a readable state in a recording medium provided in the driving support device 100, the in-vehicle device, or the server device, and is used for route generation and/or driving control. The map information 3 of this embodiment includes road information, facility information, and their attribute information. The road information and road attribute information include information such as road width, curvature radius, road shoulder structures, road traffic regulations (speed limit, lane change permission or not), road merging points, branching points, and positions where the number of lanes increases or decreases. The map information 3 of this embodiment is so-called high-definition map information, and the high-definition map information makes it possible to grasp the movement trajectory for each lane. The high-definition map information includes two-dimensional position information and/or three-dimensional position information at each map coordinate, road/lane boundary information at each map coordinate, road attribute information, lane uphill/downhill information, lane identification information, and destination lane information.

The map information 3 of this embodiment also includes information on lane boundaries that indicate the boundaries between the lane on which the vehicle is traveling and other lane boundaries. The lane on which the vehicle is traveling is the road on which the vehicle is traveling, and the form of the lane is not particularly limited. Lane boundaries exist on both the left and right sides of the traveling direction of the vehicle. The form of the lane boundary is not particularly limited, and examples include road markings and road structures. Examples of lane boundaries on road markings include lane boundaries and center lines. Examples of lane boundaries on road structures include median strips, guard rails, curbs, tunnels, or side walls of expressways. Note that lane boundaries are preset in the map information 3 for points where lane boundaries cannot be clearly identified (for example, within intersections). The preset lane boundaries are imaginary lane boundaries and are not actually existing road markings or road structures.

The host vehicle information detection device 4 of this embodiment acquires detection information related to the state of the host vehicle. The state of the host vehicle includes the current position, speed, acceleration, attitude, and vehicle performance of the host vehicle. These may be acquired from the vehicle control device 200 of the host vehicle, or from each device of the host vehicle. The host vehicle information detection device 4 of this embodiment acquires the current position of the host vehicle based on information acquired from the GPS (Global Positioning System) unit, gyro sensor, and odometry of the host vehicle. The host vehicle information detection device 4 of this embodiment also acquires the speed and acceleration of the host vehicle from the vehicle speed sensor of the host vehicle. The host vehicle information detection device 4 of this embodiment also acquires attitude data of the host vehicle from the inertial measurement unit (IMU) of the host vehicle.

The environment recognition device 5 of this embodiment recognizes object recognition information obtained from the position information acquired by the detection device 1, image information and distance measurement information around the host vehicle, and information about the environment constructed based on map information. The environment recognition device 5 of this embodiment generates environmental information around the host vehicle by integrating multiple pieces of information. The object recognition device 6 of this embodiment also uses the map information 3 and the image information and distance measurement information around the host vehicle acquired by the detection device 1 to predict the recognition and movement of objects around the host vehicle.

The vehicle control device 200 of this embodiment is an on-board computer such as an electronic control unit (ECU), and electronically controls the drive mechanism 210 that governs the driving of the vehicle. The vehicle control device 200 controls the drive device, braking device, and steering device included in the drive mechanism 210 to drive the host vehicle according to the target vehicle speed and target driving route. A control command based on the driving plan of the host vehicle is input to the vehicle control device 200 from the driving assistance device 100. The target vehicle speed, target driving route, and driving plan of the host vehicle will be described later.

The drive mechanism 210 in this embodiment includes an electric motor and/or an internal combustion engine as a driving source, a power transmission device including a drive shaft and an automatic transmission that transmits the output from these driving sources to the drive wheels, a drive device that controls the power transmission device, a braking device that brakes the wheels, and a steering device that controls the total steering wheel according to the steering angle of the steering wheel (so-called handle). A control signal corresponding to the target vehicle speed is input from the driving support device 100 to the vehicle control device 200. The vehicle control device 200 generates each control signal for these drive mechanisms 210 based on the control signal input from the driving support device 100, and executes driving control including acceleration and deceleration of the vehicle. By transmitting control information to the drive device of the drive mechanism 210, the vehicle speed control can be controlled autonomously.

The vehicle control device 200 of this embodiment also uses one or more of the lane information stored in the map information 3, the information recognized by the environment recognition device 5, and the information acquired by the object recognition device 6 to control the steering device of the drive mechanism 210 so that the vehicle travels while maintaining a predetermined lateral position (position in the left-right direction of the vehicle) with respect to the target travel route. The steering device has a steering actuator, and the steering actuator includes a motor attached to the steering column shaft. A control signal corresponding to the target travel route is input from the driving support device 100 to the vehicle control device 200. The steering device of the drive mechanism 210 performs steering control of the vehicle based on the control signal input from the vehicle control device 200. By transmitting control information to the steering device of the drive mechanism 210, the vehicle steering control can be controlled autonomously.

The driving support device 100 of this embodiment controls the driving of the vehicle to execute control to assist the driving of the vehicle. As shown in FIG. 1, the driving support device 100 of this embodiment includes a processor 10. The processor 10, which is a control device, is a computer that includes a ROM 12, which is a read only memory (ROM) that stores a program for executing driving control of the vehicle, a CPU 11, which is a central processing unit (CPU) that functions as the driving support device 100 by executing the program stored in the ROM 12, and a RAM 13, which is a random access memory (RAM) that functions as an accessible storage device. The processor 10 of this embodiment controls various functions through the cooperation of software for realizing the above functions and the above hardware. The processor 10 includes a communication device 111 and an output device 110, and outputs various output or input commands, information reading permission or information provision commands to the vehicle control device 200, the navigation device 2, the map information 3, the vehicle information detection device 4, the environment recognition device 5, and the object recognition device 6. The processor 10 exchanges information with the detection device 1, the navigation device 2, the map information 3, the vehicle information detection device 4, the environment recognition device 5, the object recognition device 6, and the vehicle control device 200.

The processor 10 of this embodiment includes a destination setting unit 120, a route planning unit 130, a driving plan unit 140, a driveable area calculation unit 150, a route calculation unit 160, and a driving behavior control unit 170, each of which performs its own function. The processor 10 of this embodiment is configured by software for realizing or executing the processing of each of the destination setting unit 120, the route planning unit 130, the driving plan unit 140, the driveable area calculation unit 150, the route calculation unit 160, and the driving behavior control unit 170, in cooperation with the hardware described above.

The control procedure by the processor 10 of this embodiment will be described with reference to FIG. 2. FIG. 2 is a flowchart showing the information processing procedure of the driving assistance system according to this embodiment. An overview of the autonomous driving control process executed by the driving assistance device 100 will be described with reference to FIG. 2.

2, the processor 10 executes a process of acquiring the current position of the vehicle based on the detection result of the vehicle information detection device 4 by the destination setting unit 120, and executes a process of setting the destination of the vehicle by the destination setting unit 120 in the following step S2. The destination may be input by the user or may be predicted by another device. In the following step S3, the processor 10 acquires various detection information including the map information 3 by the route planning unit 130. In the following step S4, the processor 10 sets a driving lane (or a driving route) for the destination set by the destination setting unit 120 by the route planning unit 130. The processor 10 sets the driving lane by the route planning unit 130 using the map information 3 and the self-position information as well as information obtained from the environment recognition device 5 and the object recognition device 6. The processor 10 sets the road on which the vehicle will travel by the route planning unit 130, but is not limited to the road, and sets the lane on which the vehicle will travel within the road.

In the next step S5, the processor 10 executes a process of planning the driving behavior of the vehicle at each point on the route using the driving plan unit 140. The driving plan specifies driving behavior such as proceed (GO) or stop (No-GO) at each point. For example, when turning right at an intersection, it executes a determination as to whether to stop at the stop line and a determination as to whether to proceed with respect to vehicles in the oncoming lane.

In the next step S6, in order to execute the driving action planned in step S5, the processor 10 executes a process in which the drivable area calculation unit 150 calculates the drivable area around the vehicle (also called the drivable area) using the map information 3, the vehicle's own position information, and information obtained from the environment recognition device 5 and the object recognition device 6. The drivable area is not limited to the lane in which the vehicle is traveling, but may be a lane adjacent to the lane in which the vehicle is traveling (also called an adjacent lane). In addition, the drivable area may be an area in which the vehicle can travel, and may be an area of the road other than that recognized as a lane.

In the next step S7, the processor 10 executes a process of generating a target driving route along which the vehicle will travel, using the route calculation unit 160. In addition, the processor 10 calculates a target vehicle speed and a profile of the target vehicle speed when traveling along the target driving route, using the driving behavior control unit 170. The processor 10 may calculate a target deceleration and target acceleration for the current vehicle speed, and their profiles, instead of or in addition to the target vehicle speed. The calculated target vehicle speed may be fed back to the target driving route generation process to generate a target driving route so as to suppress changes in the vehicle's behavior and movements (behaviors) that may cause the vehicle's occupants to feel uncomfortable. The generated target driving route may be fed back to the target vehicle speed calculation process to calculate the target vehicle speed so as to suppress changes in the vehicle's behavior and movements (behaviors) that may cause the vehicle's occupants to feel uncomfortable.

In step S8, the processor 10 executes a process of formulating a driving plan for driving the vehicle along the generated target driving route. The processor 10 also executes a process of formulating a driving plan for driving the vehicle at the calculated target vehicle speed. Then, in step S9, the output device 110 of the processor 10 outputs control commands and control command values based on the driving plan to the vehicle control device 200 via the communication device 111, and operates the drive mechanism 210, which is a variety of actuators.

The vehicle control device 200 inputs longitudinal and lateral forces that control the vehicle's driving position based on command values from the processor 10. In accordance with these inputs, the vehicle body behavior and wheel behavior are controlled so that the vehicle drives autonomously while following a target driving route. Based on these controls, at least one of the drive actuator and brake actuator of the vehicle body drive mechanism 210, and if necessary, the steering actuator of the steering device, operate autonomously, and autonomous driving control is performed to reach the destination. Of course, the drive mechanism 210 can also be operated according to command values based on manual operation.

First Embodiment
Now, the driving support device 100 sets a driving route from the current position of the vehicle acquired by the vehicle information detection device 4 to the destination set by the destination setting unit 120 using, for example, the map information 3 by the function of the route planning unit 130. In addition, the driving support device 100 plans the driving behavior of the vehicle at each point on the driving route by the function of the driving planner 140. The driving support device 100 calculates a target driving route and a target vehicle speed profile by the functions of the drivable area calculation unit 150 and the route calculation unit 160 based on the set driving route and driving behavior. Here, the driving support device 100 compares the set driving route and driving behavior with the current position of the vehicle acquired by the vehicle information detection device 4 to determine whether or not a lane change is necessary to drive along the set driving route, and when it is determined that a lane change is necessary, autonomously controls the lane change of the vehicle. Hereinafter, the autonomous control of the lane change of the vehicle by the driving support device 100 will be described using the driving scene shown in FIG. 11A as an example.

Figure 11A is a plan view showing a driving scene assuming driving in an urban area, and on the road shown in Figure 11, a vehicle is traveling from the left side to the right side of the drawing. In the driving scene shown in Figure 11A, the host vehicle V1 is currently traveling in the host lane L1, and the driving assistance device 100 has determined that the host vehicle V1 needs to change lanes from the host lane L1 to the adjacent lane L2. In addition, there is a traffic light ahead where the host vehicle V1 is traveling, and the light indicates a stop signal. Then, following the stop signal, other vehicles V3 and V4 are stopped in the host lane L1, and other vehicle V5 is stopped in the adjacent lane L2.

In this case, the driving support device 100 first uses the function of the drivable area calculation unit 150 to set an area Zx in which the host vehicle V1 can travel, as shown by a dashed line in FIG. 11A. The area Zx is set so as to avoid contact between the host vehicle V1 and the other vehicles V3 and V5 that are stopped. For example, in the driving scene shown in FIG. 11A, the end E1x on the host vehicle lane L1 side in the driving direction ahead of the area Zx is set at a position with a predetermined distance from the rear end of the other vehicle V3 in order to avoid contact between the rear end of the other vehicle V3 that is stopped and the front end of the host vehicle V1. Similarly, the end E2x on the adjacent lane L2 side in the driving direction ahead of the area Zx is set at a position with a predetermined distance from the rear end of the other vehicle V5 in order to avoid contact between the rear end of the other vehicle V5 that is stopped and the front end of the host vehicle V1. Next, the driving support device 100 uses the function of the route calculation unit 160 to set the position P2x where the lane change of the host vehicle V1 is completed to a position in the adjacent lane L2 within the area Zx. Then, the driving support device 100 generates a driving trajectory Tx along which the host vehicle V1 travels from the current position P1 to a position P2x, using the function of the route calculation unit 160. With the support of the driving support device 100, the host vehicle V1 travels along the driving trajectory Tx and stops at the position P2x.

Here, in the driving scene shown in FIG. 11A, there is no other vehicle traveling ahead of the host vehicle V1. However, as in the driving scene shown in FIG. 11B, when there is a first preceding vehicle V2a, which is another vehicle traveling ahead of the host vehicle V1 in the adjacent lane L2, the host vehicle V1 may approach or come into contact with the first preceding vehicle V2a when traveling along the traveling trajectory Tx. For example, the first preceding vehicle V2a currently traveling at position Q1x decelerates in front of the other vehicle V5 in response to a stop signal ahead and stops at position Q2x. In this case, the first preceding vehicle V2a stops at position Q2x before the host vehicle V1 reaches position P2x, so the host vehicle V1 cannot reach position P2x by traveling along the traveling trajectory Tx and cannot complete the lane change. Then, in order to avoid contact with the stopped first preceding vehicle V2a, the host vehicle V1 follows the first preceding vehicle V2a and stops at position P3x on the traveling trajectory Tx.

In this way, in the driving assistance by the driving assistance device 100 according to the comparative example of the present invention, when the first preceding vehicle V2a is present, the host vehicle V1 may be unable to secure a distance between itself and the stopped first preceding vehicle V2a, and may be forced to stop in the middle of changing lanes. As a result, the behavior of the host vehicle V1 during the lane change may become unstable, and the host vehicle V1 may stop at position P3x that straddles the host lane L1 and the adjacent lane L2. In addition, when the host vehicle V1 stops at position P3x, the host vehicle V1 cannot move from position P3x unless the first preceding vehicle V2a stopped at position Q2x resumes traveling. Therefore, the host vehicle V1 will be in an unstable state of being stopped at position P3x until the first preceding vehicle V2a resumes traveling.

In consideration of these points, the present inventors have invented a driving support device 100 that stabilizes the behavior of the host vehicle V1 during lane change from the host lane L1 to the adjacent lane L2 when a first preceding vehicle V2a is detected in the adjacent lane L2. That is, the driving support device 100 according to the first embodiment of the present invention detects the first preceding vehicle V2a, which is another vehicle traveling on the adjacent lane L2, in front of the host vehicle V1 when autonomously controlling the lane change from the host lane L1 to the adjacent lane L2. When the driving support device 100 detects the first preceding vehicle V2a, it calculates a first estimated stop position, which is a stop position when it is assumed that the first preceding vehicle V2a will decelerate and stop, before starting autonomous control of the lane change from the host lane L1 to the adjacent lane L2. After calculating the first estimated stop position, the driving support device 100 uses the calculated first estimated stop position to calculate a first area on the own lane L1 and the adjacent lane L2 in which the own vehicle V1 can travel to change lanes to the adjacent lane L2 behind the first preceding vehicle V2a. The driving support device 100 then sets the position where the lane change is completed within the first area as the first lane change completion position, generates a first trajectory, which is a driving trajectory for completing the lane change by the first lane change completion position, and after generating the first trajectory, starts autonomous control of lane change along the first trajectory. The autonomous lane change control of the driving support device 100 according to the first embodiment will be described below using the driving scenes shown in Figures 3A to 3B as examples.

Figures 3A and 3B are plan views showing a driving scene similar to that shown in Figure 11A. That is, in the driving scene shown in Figure 3A, the host vehicle V1 is traveling at a current position P1 in the host lane L1, and needs to change lanes from the host lane L1 to the adjacent lane L2. In addition, there is a traffic light ahead of the host vehicle V1, which indicates a stop signal, and other vehicles V3 and V4 are stopped in the host lane L1, and other vehicle V5 is stopped in the adjacent lane L2 in accordance with the signal.

[Calculation of first region Z1]
When autonomously controlling a lane change from the own lane L1 to the adjacent lane L2, the driving support device 100 according to the first embodiment of the present invention first detects a first preceding vehicle V2a in the adjacent lane L2 by using the detection device 1, such as an image capture device or a distance measurement device, the environment recognition device 5, and the object recognition device 6, through the function of the route calculation unit 160. In the driving scene shown in Fig. 3A, the driving support device 100 detects the first preceding vehicle V2a traveling at the current position Q1a.

When the first preceding vehicle V2a is detected, the driving support device 100 detects the traveling position and vehicle speed of the first preceding vehicle V2a using a detection device 1 such as an imaging device or a distance measuring device by the function of the route calculation unit 160. In addition, the driving support device 100 detects the traveling position and vehicle speed of the host vehicle V1 by the function of the route calculation unit 160 using map information 3 and a host vehicle information detection device 4 such as a vehicle speed sensor. Then, the driving support device 100 uses the function of the route calculation unit 160 to determine whether the host vehicle V1 will change lanes to a position behind the first preceding vehicle V2a based on the vehicle speed difference between the host vehicle V1 and the first preceding vehicle V2a and the positional relationship between the host vehicle V1 and the first preceding vehicle V2a using the environment recognition device 5 and object recognition device 6. For example, in a driving scene in which the host vehicle V1 is traveling at a speed faster than the first preceding vehicle V2a and the host vehicle V1 is traveling side by side with the first preceding vehicle V2a, the driving support device 100 determines that the host vehicle V1 will change lanes to a position in front of the first preceding vehicle V2a. In this case, the behavior of the host vehicle V1 is more stable when the host vehicle V1 changes lanes by overtaking the first preceding vehicle V2a while maintaining the vehicle speed, rather than decelerating and changing lanes to a position behind the first preceding vehicle V2a. On the other hand, in a driving scene in which the host vehicle V1 is traveling at a speed slower than the first preceding vehicle V2a and the first preceding vehicle V2a is traveling ahead of the host vehicle V1, the driving support device 100 determines that the host vehicle V1 will change lanes to a position behind the first preceding vehicle V2a. This is because the behavior of the host vehicle V1 becomes unstable when the host vehicle V1 simultaneously overtakes the first preceding vehicle V2a with acceleration and changes lanes from the host vehicle lane L1 to the adjacent lane L2.

Next, the driving support device 100 uses the function of the route calculation unit 160 to calculate a first estimated stop position Q2a when it is assumed that the first preceding vehicle V2a will decelerate and stop before starting autonomous control of lane change from the own lane L1 to the adjacent lane L2. The method of calculating the first estimated stop position Q2a is not particularly limited, but for example, when the first preceding vehicle V2a is detected, the current vehicle speed of the first preceding vehicle V2a detected by a detection device 1 such as a distance measuring device is used to calculate the position where the first preceding vehicle V2a is estimated to stop and stop when it is assumed that the first preceding vehicle V2a has decelerated from the current position Q1a at a predetermined deceleration (for example, 0.1 G) as the first estimated stop position Q2a. The predetermined deceleration may be constant or may be a deceleration estimated from the behavior of the detected first preceding vehicle V2a. In addition, when the first preceding vehicle V2a has actually started to decelerate, the detected deceleration of the first preceding vehicle V2a may be used.

Alternatively, the first estimated stop position Q2a can be calculated from the driving scene of the vehicle V1 and the first preceding vehicle V2a. For example, if it is known from the map information 3 and the detection results of the vehicle information detection device 4 that an intersection exists ahead of the vehicle V1 on the driving route, and the detection results of the detection device 1 such as an imaging device and the environment recognition device 5 are used to detect that the traffic light at the intersection is presenting a stop signal to the vehicle V1, it is estimated that the first preceding vehicle V2a will stop in front of the stop line, and the first estimated stop position Q2a is calculated.

Alternatively, or in addition, the first estimated stop position Q2a may be calculated when the current vehicle speed of the detected first preceding vehicle V2a is equal to or lower than a predetermined vehicle speed. For example, when the first preceding vehicle V2a is traveling at high speed, the first estimated stop position Q2a of the first preceding vehicle V2a will be located away from the host vehicle V1, and it is considered that the host vehicle V1 can secure a distance to travel in order to change lanes from the host lane L1 to the adjacent lane L2. The predetermined vehicle speed can be set to an appropriate value that can secure a distance to travel in order to change lanes from the host vehicle V1 to the adjacent lane L2, based on the relationship between the vehicle speed and the vehicle braking distance.

In addition, when a plurality of first preceding vehicles are detected by the detection device 1 such as an imaging device and a distance measuring device, the first estimated stop position Q2a is calculated assuming that the plurality of first preceding vehicles will stop with a predetermined vehicle distance D1 between them. Specifically, assuming that the plurality of first preceding vehicles will decelerate and stop, the stop positions of the plurality of first preceding vehicles are estimated, and the estimated stop position of the first preceding vehicle closest to the vehicle among these estimated stop positions is set as the first estimated stop position Q2a. For example, in the driving scene of FIG. 3A, it is assumed that the other vehicle V5 is not stopped but is running, and the other vehicles V2a and V5 are detected as the first preceding vehicles. In this case, the driving support device 100 uses the function of the route calculation unit 160 to estimate the stop positions when the first preceding vehicles V2a and V5 decelerate and stop, assuming that the two first preceding vehicles V2a and V5 will stop with a predetermined vehicle distance D1 between them. Then, the driving support device 100 calculates the estimated stop position of the first leading vehicle V2a, which is the first leading vehicle that is closer to the vehicle of the two first leading vehicles, as the first estimated stop position Q2a. The predetermined inter-vehicle distance D1 can be set to an appropriate distance that can avoid contact between multiple first leading vehicles.

After calculating the first estimated stop position Q2a, the driving support device 100 uses the first estimated stop position Q2a to calculate the first area Z1 in which the host vehicle V1 can travel to change lanes to a position behind the first preceding vehicle V2a, using the function of the drivable area calculation unit 150. The first area Z1 shown by the dashed line in FIG. 3A is set to avoid contact between the host vehicle V1 and the other vehicle V3 that is stopped and the first preceding vehicle V2a that is assumed to stop at the first estimated stop position Q2a. For example, in the driving scene shown in FIG. 3A, the end E1a on the host vehicle lane L1 side ahead of the driving direction of the first area Z1 is set at a position with a predetermined distance from the rear end of the other vehicle V3 in order to avoid contact between the rear end of the other vehicle V3 that is stopped and the tip of the host vehicle V1. In addition, the end E2a of the first area Z1 on the adjacent lane L2 side in the forward driving direction is set at a position with a predetermined distance from the rear end of the first preceding vehicle V2a, which is assumed to stop at the first estimated stop position Q2a, in order to avoid contact between the rear end of the first preceding vehicle V2a, which is assumed to stop at the first estimated stop position Q2a, and the front end of the host vehicle V1. The predetermined distance can be set to an appropriate value that can avoid contact between the host vehicle V1 and the other vehicle V3 and the first preceding vehicle V2a.

[Generation of first locus T1]
3B, after calculating the first area Z1, the driving support device 100 sets the position where the lane change is completed in the first area Z1 in the adjacent lane L2 as the first lane change completion position P2a by the function of the route calculation unit 160. The first lane change completion position P2a can be set to an appropriate position where the host vehicle V1 can change lanes with stable behavior as long as it is within the first area Z1. Then, the driving support device 100 generates a first trajectory T1 along which the host vehicle V1 travels from the current position P1 to the first lane change completion position P2a by the function of the route calculation unit 160. When the first lane change completion position P2a is set to the position shown in FIG. 3B, the driving support device 100 generates, for example, the first trajectory T1 shown in FIG. 3B by the function of the route calculation unit 160. After generating the first trajectory T1, the driving assistance device 100, through the function of the driving behavior control unit 170, uses the vehicle control device 200 to operate the drive mechanism 210, which is an actuator such as a drive actuator and a braking actuator, and begins assisting the host vehicle V1 in changing lanes along the first trajectory T1.

The first trajectory T1 generated by the driving support device 100 can be a driving trajectory in which the host vehicle V1 enters the adjacent lane L2 completely before the host vehicle V1 reaches the position E3a of the adjacent lane L2 by setting the first lane change completion position P2a behind the position E3a of the adjacent lane L2 adjacent to the end E1a of the first area Z1 in the host vehicle L1 in the forward driving direction. In the first embodiment, the host vehicle V1 entering the adjacent lane L2 completely means that the entire body of the host vehicle V1 is included in the adjacent lane L2 when the host vehicle V1 is viewed from above. In addition to this, or instead of this, the first trajectory T1 generated by the driving support device 100 can be a driving trajectory in which the host vehicle V1 enters the adjacent lane L2 completely before the host vehicle V1 reaches a position a predetermined distance behind the position E3a of the adjacent lane L2 in the driving direction. The predetermined distance can be set to an appropriate position where the host vehicle V1 can change lanes with stable behavior.

In addition, when the driving support device 100 generates the first trajectory T1 by the function of the route calculation unit 160, the shorter the distance between the current position P1 of the vehicle V1 and the first lane change completion position P2a, the closer the position of the vehicle V1 to start autonomous steering control on the first trajectory T1. In the case of the first trajectory T1 shown in FIG. 3B, the vehicle V1 starts steering control to the right from position S1a, changes the steering direction from the right to the left at position S2a, completes steering control at position S3a, and returns the steering wheel to a neutral position. In the driving scene shown in FIG. 3B, if the first lane change completion position P2a is set to a position behind the position shown in FIG. 3B (i.e., closer to the current position P1), the position S1a where the autonomous steering control to the right is started on the first trajectory T1 is set to a position behind the position shown in FIG. 3B (i.e., closer to the current position P1).

In addition to this, or instead of this, when generating the first trajectory T1 by the function of the route calculation unit 160, the driving support device 100 may set the distance from the position S1a where the steering control of the autonomous control is started to the position S3a where the steering control is completed to the same distance as the distance required from the start to the completion of the steering control of the autonomous control of the lane change when the host vehicle V1 changes lanes from the host vehicle lane L1 to the adjacent lane L2 when the first preceding vehicle V2a is not detected. For example, in the driving trajectory Tx generated when the first preceding vehicle V2a is not detected as shown in FIG. 11A, the host vehicle V1 starts steering control to the right from position S1x, changes the steering direction from the right to the left at position S2x, completes steering control at position S3x, and stops at position P2x. The driving support device 100 sets the distance from the position S1a where the autonomous steering control starts to the position S3a where the steering control ends on the first trajectory T1 shown in FIG. 3B to the same distance as the distance from the position S1x where the autonomous steering control starts to the position S3x where the steering control ends on the driving trajectory Tx. In order to set the distance from the position S1a to the position S3a to the same distance from the position S1x to the position S3x, the driving support device 100 adjusts the distance from the current position P1 to the position S1a where the steering control starts on the first trajectory T1, for example, by setting the position S1a.

In addition to this, or instead of this, when generating the first trajectory T1 by the function of the route calculation unit 160, the driving support device 100 may set the distance from the position S1a where the steering control of the autonomous control of the lane change is started to the position S3a where the steering control is completed to a distance greater than or equal to the distance required to generate the first trajectory T1 having a curvature that makes the centrifugal force generated in the host vehicle V1 when changing lanes less than a predetermined value, in order to make the centrifugal force generated in the host vehicle V1 when changing lanes less than a predetermined value. For example, the driving support device 100 can ensure the distance required to generate the first trajectory T1 having the curvature by setting the distance of the straight section from the current position P1 to the position S1a where the steering control of the autonomous control is started in the first trajectory T1 to be short. The predetermined value of the centrifugal force can be set to an appropriate value that does not cause discomfort to the occupants of the host vehicle V1 and allows the host vehicle V1 to change lanes with stable behavior.

[Correction of the first locus T1]
The driving support device 100 according to the first embodiment of the present invention calculates a first estimated stop position Q2a where the first preceding vehicle V2a is estimated to stop before starting the autonomous control of the driving operation of the lane change. Then, even if the first preceding vehicle V2a stops at the first estimated stop position Q2a, the autonomous control of the driving operation starts after generating a first trajectory T1 where the host vehicle V1 can complete the lane change from the host lane L1 to the adjacent lane L2. However, the first preceding vehicle V2a may stop at a position behind the first estimated stop position Q2a in the driving direction when, for example, another vehicle enters the adjacent lane L2 from a lane adjacent to the adjacent lane L2 or when an obstacle is found ahead in the driving direction of the adjacent lane L2.

In this case, the host vehicle V1 is unable to maintain a sufficient distance from the first preceding vehicle V2a, which has stopped at a position further back in the driving direction than the first estimated stop position Q2a, and may be forced to stop midway through the lane change to avoid contact with the first preceding vehicle V2a. As a result, the behavior of the host vehicle V1 becomes unstable during the lane change, and the host vehicle V1 may stop at a position straddling the host lane L1 and the adjacent lane L2. In that case, the host vehicle V1 must wait for the first preceding vehicle V2a to resume driving in order to resume driving, and the host vehicle V1 will be in an unstable state until the first preceding vehicle V2a resumes driving.

In view of these points, in order to further stabilize the behavior of the host vehicle V1 during lane change, the driving support device 100 according to the first embodiment of the present invention can correct the first trajectory T1. That is, after starting autonomous control of lane change along the first trajectory T1, the driving support device 100 detects a first stop position, which is the actual stop position of the first preceding vehicle V2a. From the detected first stop position, the driving support device 100 determines whether the host vehicle V1 completes the lane change at the first lane change completion position P2a, and if it determines that the lane change is not completed at the first lane change completion position P2a, it uses the detected first stop position to calculate the position where the host vehicle V1 stops and stops. Then, at the position where the host vehicle V1 stops and stops, the first trajectory T1 is corrected so that the host vehicle V1 enters the adjacent lane L2, and the driving of the host vehicle V1 is supported using the corrected new first trajectory T1. Below, we will explain how the driving assistance device 100 corrects the first trajectory T1 using the driving scenes shown in Figures 4A and 4B as examples.

Figures 4A-4B are plan views showing a driving scene after autonomous control of driving operation by the driving assistance device 100 is started after generating the first trajectory T1 shown in Figure 3B, and the host vehicle V1 has driven from position P1 before the lane change shown in Figure 3B to position P1a shown in Figure 4A. In the driving scene shown in Figure 4A, the host vehicle V1 is driving at position P1a in the host lane L1, and is in the process of changing lanes from the host lane L1 to adjacent lane L2. In addition, there is a traffic light ahead of the host vehicle V1, which indicates a stop signal, and other vehicles V3 and V4 are stopped in the host lane L1, and other vehicle V5 is stopped in the adjacent lane L2 in accordance with the signal. Furthermore, an obstacle O is present in the adjacent lane L2 behind the other vehicle V5, i.e., in front of the first leading vehicle V2a, and in order to avoid contact with the obstacle O, the first leading vehicle V2a stops at a stop position Q3a, which is a position behind the first estimated stop position Q2a in the driving direction.

In this case, the driving support device 100 uses the function of the route calculation unit 160 to detect the first stop position Q3a, which is the actual stop position of the first preceding vehicle V2a, using the detection device 1, such as an image capture device or a distance measurement device, the environment recognition device 5, and the object recognition device 6. In the driving scene shown in FIG. 4A, the first preceding vehicle V2a is stopped at the first stop position Q3a to avoid contact with the obstacle O, so position Q3a is detected as the first stop position.

After detecting the first stop position Q3a, the driving support device 100 uses the function of the route calculation unit 160 to determine whether the host vehicle V1 will complete the lane change at the first lane change completion position P2a. Whether the lane change is completed is determined by comparing the first stop position Q3a with the first lane change completion position P2a. In the driving scene shown in FIG. 4A, the stop position Q3a is included in the first area Z1 and overlaps with the first lane change completion position P2a, so the driving support device 100 determines that the lane change is not completed at the first lane change completion position P2a. In contrast, if the first lane change completion position P2a is located behind the first stop position Q3a in the driving direction, the driving support device 100 determines that the lane change is completed at the first lane change completion position P2a.

When it is determined that the lane change is not completed at the first lane change completion position P2a, the driving support device 100 uses the detected first stop position Q3a by the function of the route calculation unit 160 to calculate the position where the host vehicle V1 will stop because the vehicle distance from the first preceding vehicle V2a cannot be secured. The position where the host vehicle V1 will stop is calculated, for example, using the vehicle distance between the host vehicle V1 and the first preceding vehicle V2a. In the driving scene shown in FIG. 4A, the driving support device 100 uses the function of the route calculation unit 160 to calculate a position P3a on the first trajectory T1 where the vehicle distance between the host vehicle V1 and the first preceding vehicle V2a is equal to or less than a predetermined value from the vehicle distance between the host vehicle V1 and the first preceding vehicle V2a detected by the detection device 1 such as a distance measuring device and the object recognition device 6. The vehicle distance can be set to an appropriate value that can avoid contact between the host vehicle V1 and the first preceding vehicle V2a.

Moving on to FIG. 4B, the driving assistance device 100 corrects the first trajectory T1 by the function of the route calculation unit 160 so that the host vehicle V1 is completely within the adjacent lane L2 at position P3a where the host vehicle V1 stops. In the first embodiment, the host vehicle V1 being completely within the adjacent lane L2 means that the entire body of the host vehicle V1 is included in the adjacent lane L2 when the host vehicle V1 is viewed from above. Also, in the first embodiment, the host vehicle V1 being completely within the adjacent lane L2 at position P3a where the host vehicle V1 stops means that the host vehicle V1 is completely within the adjacent lane L2 when it reaches the same position as position P3a in the driving direction of the road.

To correct the first trajectory T1, the driving assistance device 100 sets a new first lane change completion position where the host vehicle V1 can enter the adjacent lane L2, for example, in a position in the same driving direction as position P3a, and generates a driving trajectory from the current driving position P1a to the new first lane change completion position. In the driving scene shown in FIG. 4B, the driving assistance device 100 sets a new first lane change completion position P4a where the host vehicle V1 can enter the adjacent lane L2, in a position in the same driving direction as position P3a. Then, the driving assistance device 100 generates a new first trajectory T1a traveling from position P1a to position P4a, as shown in FIG. 4B.

When the driving support device 100 can generate a new first trajectory T1a, the driving support device 100 uses the vehicle control device 200 to autonomously control the driving operation of the host vehicle V1 by the function of the driving behavior control unit 170 so that the host vehicle V1 drives along the new first trajectory T1a. In the driving scene shown in FIG. 4B, the host vehicle V1 drives from position P1a to position P4a along the first trajectory T1a and stops at position P4a. On the other hand, when the inter-vehicle distance between the host vehicle V1 and the first preceding vehicle V2a is already close, or when the first preceding vehicle V2a suddenly decelerates and stops, the driving support device 100 may not be able to set a new first lane change completion position P4a, or may only be able to generate the first trajectory T1a, which makes the behavior of the host vehicle unstable. In such a case, the driving support device 100 may, for example, interrupt the autonomous control of the driving operation of the host vehicle V1 and switch to manual driving by the driver.

[Calculation process of first area Z1]
Next, the autonomous control process for lane change according to the first embodiment will be described with reference to Fig. 5 to Fig. 7. Fig. 5 to Fig. 7 are flowcharts showing the autonomous control process in the processor 10 according to the present embodiment. Note that the autonomous control process described below is executed at predetermined time intervals by the driving assistance device 100 according to the present embodiment.

Figure 5 is an example of a subroutine of step S6 shown in Figure 2 according to the first embodiment. When calculating the first area Z1 in which the host vehicle V1 can travel in order to change lanes from the host lane L1 to the adjacent lane L2, step S6 performs processing, for example, according to the procedure shown in Figure 5.

In step S61a, the processor 10 uses the function of the route calculation unit 160 to determine whether or not the host vehicle V1 needs to change lanes from the host lane L1 to the adjacent lane L2 in order for the host vehicle V1 to travel along the travel route set in step S4 of FIG. 2 and the driving plan set in step S5. If it is determined that a lane change from the host lane L1 to the adjacent lane L2 is not necessary (step S61a: No), the process proceeds to step S66a. On the other hand, if it is determined that a lane change from the host lane L1 to the adjacent lane L2 is necessary (step S61a: Yes), the process proceeds to step S62a.

In step S62a, the processor 10 uses the detection device 1, the environment recognition device 5, and the object recognition device 6 through the functions of the path calculation unit 160 to determine whether or not a first preceding vehicle V2a of the host vehicle V1 traveling in the adjacent lane L2 is present. If the first preceding vehicle V2a is not detected, it is determined that the first preceding vehicle V2a is not present (step S62a: No) and the process proceeds to step S66a. On the other hand, if the first preceding vehicle V2a is detected, it is determined that the first preceding vehicle V2a is present (step S62a: Yes) and the process proceeds to step S63a.

In step S63a, the processor 10 uses the function of the route calculation unit 160 to determine whether the host vehicle V1 will change lanes to a position behind the first preceding vehicle V2a, using the detection device 1, the host vehicle information detection device 4, the environment recognition device 5, and the object recognition device 6, the driving route set in step S4, and the driving plan set in step S5. If it is determined that the host vehicle V1 will change lanes to a position in front of the first preceding vehicle V2a, not to a position behind the first preceding vehicle V2a (step S63a: No), the process proceeds to step S66a. On the other hand, if it is determined that the host vehicle V1 will change lanes to a position behind the first preceding vehicle V2a (step S63a: Yes), the process proceeds to step S64a.

In step S64a, the processor 10 uses the function of the route calculation unit 160 to calculate a first estimated stop position Q2a when it is estimated that the first preceding vehicle V2a will decelerate and stop. In the following step S65a, the processor 10 uses the function of the route calculation unit 160 to calculate a first area Z1 in which the host vehicle V1 can travel in order to change lanes from the host lane L1 to the adjacent lane L2. After calculating the first area Z1 as the drivable area in step S65a, the process proceeds to step S7 in FIG. 2, where the processor 10 uses the function of the route calculation unit 160 to calculate a first trajectory T1, which is a target travel route, for the first area Z1.

On the other hand, when the process proceeds from step S61a, step S62a, or step S63a to step S66a, the processor 10 calculates a drivable area that satisfies the predetermined conditions for the driving route set in step S4 and the driving plan set in step S5. Then, after calculating the drivable area in step S66a, the process proceeds to step S7 in FIG. 2, where the processor 10 uses the function of the route calculation unit 160 to calculate a target driving route for the drivable area in accordance with the predetermined conditions.

[Generation process of first locus T1]
Fig. 6 is an example of a subroutine according to the first embodiment of step S7 shown in Fig. 2. When generating a first trajectory T1 along which the host vehicle V1 travels when changing lanes from the host lane L1 to the adjacent lane L2, step S7 performs processing, for example, according to the procedure shown in Fig. 6.

In step S71a, the processor 10 uses the function of the path calculation unit 160 to set the position where the lane change of the host vehicle V1 from the host lane L1 to the adjacent lane L2 is completed within the first area Z1 as the first lane change completion position P2a. In the following step S72a, the processor 10 uses the function of the path calculation unit 160 to generate a first trajectory T1 that moves from the current position P1 of the host vehicle V1 to the first lane change completion position P2a.

After calculating the first trajectory T1 as the target driving route in step S72a, the process proceeds to step S8 in FIG. 2, where the processor 10 uses the function of the driving behavior control unit 170 to calculate the target vehicle speed and the target vehicle speed profile when the host vehicle V1 drives along the first trajectory T1. In the following step S9, the processor 10 uses the function of the driving behavior control unit 170 to autonomously control the driving operation of the host vehicle V1 using the vehicle control device 200.

[Correction process of first locus T1]
Fig. 7 is another example of a subroutine according to the first embodiment of step S7 shown in Fig. 2. When correcting the first trajectory T1 after starting the autonomous control of lane change from the own lane L1 to the adjacent lane L2, processing is performed in step S7, for example, according to the procedure shown in Fig. 7.

In step S73a, the processor 10 detects the first stop position Q3a, which is the actual stop position of the first preceding vehicle V2a, using the detection device 1, the environment recognition device 5, and the object recognition device 6 through the function of the path calculation unit 160. In the following step S74a, the processor 10 uses the detection device 1, the host vehicle information detection device 4, the environment recognition device 5, the object recognition device 6, the first trajectory T1, and the first stop position Q3a through the function of the path calculation unit 160 to determine whether the host vehicle V1 completes the lane change at the first lane change completion position P2a. If it is determined that the lane change of the host vehicle V1 is completed at the first lane change completion position P2a (step S74a: Yes), the process proceeds to step S8 in FIG. 2 and the subsequent step S9, and the autonomous control of the traveling operation along the first trajectory T1 is continued. On the other hand, if it is determined that the lane change of the host vehicle V1 is not completed at the first lane change completion position P2a (step S74a: No), the process proceeds to step S75a.

In step S75a, the processor 10 uses the function of the path calculation unit 160 to calculate a position P3a where the host vehicle V1 will stop, using the detection device 1, the host vehicle information detection device 4, the environment recognition device 5, and the object recognition device 6, as well as the first trajectory T1 and the first stop position Q3a. In the following step S76a, the processor 10 corrects the first trajectory T1 so that the host vehicle V1 can enter the adjacent lane L2 at the position P3a where the host vehicle V1 stops.

In the next step S77a, the processor 10 uses the function of the route calculation unit 160 to determine whether or not the first trajectory T1 can be corrected so that the host vehicle V1 can enter the adjacent lane L2 at the position P3a where the host vehicle V1 stops. If the first trajectory T1 can be corrected so that the host vehicle V1 can enter the adjacent lane L2 (step S77a: Yes), the process proceeds to step S8 in FIG. 2, where the traveling operation of the host vehicle V1 is autonomously controlled along the new first trajectory T1a. On the other hand, if the first trajectory T1 cannot be corrected so that the host vehicle V1 can enter the adjacent lane L2 (step S77a: No), the process switches to manual driving by the driver, for example, by interrupting the autonomous control of the traveling operation of the host vehicle V1.

Second Embodiment
In Figure 11B, there is a first preceding vehicle V2a, which is another vehicle traveling in front of the host vehicle V1 in the adjacent lane L2.However, even if there is a second preceding vehicle V2b, which is another vehicle traveling in front of the host vehicle V1 in the host lane L1, as in the driving scene shown in Figure 11C, the host vehicle V1 may approach or come into contact with the second preceding vehicle V2b.

Figure 11C is a plan view showing a driving scene similar to the driving scene shown in Figure 11A. That is, in the driving scene shown in Figure 11C, the host vehicle V1 is currently traveling in the host lane L1, and the driving assistance device 100 has determined that the host vehicle V1 needs to change lanes from the host lane L1 to the adjacent lane L2. Also, there is a traffic light ahead of the host vehicle V1, and the traffic light indicates a stop signal. Then, in accordance with the stop signal, other vehicles V3 and V4 are stopped in the host lane L1, and other vehicle V5 is stopped in the adjacent lane L2.

In this case, the driving support device 100 first uses the function of the drivable area calculation unit 150 to set an area Zy in which the host vehicle V1 can travel, as shown by a dashed line in FIG. 11C. The area Zy is set so as to avoid contact between the host vehicle V1 and the other vehicles V3 and V5 that are stopped. For example, in the driving scene shown in FIG. 11C, the end E1y on the host vehicle lane L1 side in the driving direction ahead of the area Zy is set to a position with a predetermined distance from the rear end of the other vehicle V3 in order to avoid contact between the rear end of the other vehicle V3 that is stopped and the front end of the host vehicle V1. Similarly, the end E2y on the adjacent lane L2 side in the driving direction ahead of the area Zy is set to a position with a predetermined distance from the rear end of the other vehicle V5 in order to avoid contact between the rear end of the other vehicle V5 that is stopped and the front end of the host vehicle V1. Next, the driving support device 100 uses the function of the route calculation unit 160 to set the position P2y where the lane change of the host vehicle V1 is completed to a position in the adjacent lane L2 within the area Zy. Then, the driving support device 100 generates a driving trajectory Ty along which the host vehicle V1 travels from the current position P1 to a position P2y, using the function of the route calculation unit 160. With the support of the driving support device 100, the host vehicle V1 travels along the driving trajectory Ty and stops at the position P2y.

Here, as shown in FIG. 11C, when the second preceding vehicle V2b of the host vehicle V1 exists in the host vehicle lane L1, the host vehicle V1 may approach or come into contact with the second preceding vehicle V2b when traveling along the travel trajectory Ty. For example, the second preceding vehicle V2b currently traveling at position Q1y follows a stop signal ahead and decelerates in front of the other vehicle V3 and stops at position Q2y. In this case, the second preceding vehicle V2b stops at position Q2y before the host vehicle V1 can enter the adjacent lane L2 completely, so when the host vehicle V1 travels along the travel trajectory Ty, it will come into contact with the second preceding vehicle V2b stopped at position Q2y when it reaches position P3y. Therefore, in order to avoid contact with the stopped second preceding vehicle V2b, the host vehicle V1 will follow the second preceding vehicle V2b and stop at position P3y on the travel trajectory Ty, and will not be able to complete the lane change.

In this way, in the driving assistance by the driving assistance device 100 according to the comparative example of the present invention, when the second preceding vehicle V2b is present, the host vehicle V1 may be unable to secure a distance between the stopped second preceding vehicle V2b and the host vehicle V1 may be forced to stop in the middle of changing lanes. As a result, the behavior of the host vehicle V1 during the lane change may become unstable, and the host vehicle V1 may stop at position P3y that straddles the host vehicle lane L1 and the adjacent lane L2. In addition, when the host vehicle V1 stops at position P3y, the host vehicle V1 cannot move from position P3y unless the second preceding vehicle V2b, which has stopped at position Q2y, resumes traveling. Therefore, the host vehicle V1 will be in an unstable state of being stopped at position P3y until the second preceding vehicle V2b resumes traveling.

In view of these points, the present inventors have invented a driving support device 100 that stabilizes the behavior of the host vehicle V1 during lane change from the host lane L1 to the adjacent lane L2 when a second preceding vehicle V2b is detected in the host lane L1. That is, the driving support device 100 according to the second embodiment of the present invention detects the second preceding vehicle V2b, which is another vehicle traveling in the host lane L1, in front of the host vehicle V1 when autonomously controlling the lane change from the host lane L1 to the adjacent lane L2. When the second preceding vehicle V2b is detected, the driving support device 100 calculates a second estimated stop position, which is a stop position when it is assumed that the second preceding vehicle V2b will decelerate and stop, before starting the autonomous control of the lane change from the host lane L1 to the adjacent lane L2. After calculating the second estimated stop position, the driving support device 100 uses the calculated second estimated stop position to calculate a second area on the host lane L1 and the adjacent lane L2 in which the host vehicle V1 can travel to change lanes to the adjacent lane L2. Then, the driving assistance device 100 sets the position where the lane change is completed within the second area as the second lane change completion position, generates a second trajectory, which is a driving trajectory for completing the lane change by the second lane change completion position, and starts autonomous control of the lane change along the second trajectory after generating the second trajectory. The autonomous control of the lane change by the driving assistance device 100 according to the second embodiment will be described below using the driving scenes shown in Figures 8A and 8B as examples.

Figures 8A and 8B are plan views showing a driving scene similar to that of Figure 11A. That is, in the driving scene shown in Figure 8A, the host vehicle V1 is traveling at a current position P1 in the host lane L1, and needs to change lanes from the host lane L1 to the adjacent lane L2. In addition, there is a traffic light ahead of the host vehicle V1, which indicates a stop signal, and other vehicles V3 and V4 are stopped in the host lane L1, and other vehicle V5 is stopped in the adjacent lane L2 in accordance with the signal.

[Calculation of second region Z2]
When autonomously controlling a lane change from the own lane L1 to the adjacent lane L2, the driving support device 100 according to the second embodiment of the present invention first detects a second preceding vehicle V2b in the own lane L1 by using the detection device 1, such as an image capture device or a distance measurement device, the environment recognition device 5, and the object recognition device 6, by using the function of the route calculation unit 160. In the driving scene shown in Fig. 8A, the driving support device 100 detects the second preceding vehicle V2b traveling at the current position Q1b.

When the second preceding vehicle V2b is detected, the driving support device 100 uses the function of the route calculation unit 160 to calculate a second estimated stop position Q2b when the second preceding vehicle V2b is assumed to decelerate and stop before starting autonomous control of lane change from the own lane L1 to the adjacent lane L2. The method of calculating the second estimated stop position Q2b is not particularly limited, but for example, when the second preceding vehicle V2b is detected, the current vehicle speed of the second preceding vehicle V2b detected by the detection device 1 such as a distance measuring device is used to calculate the position where the second preceding vehicle V2b is estimated to stop and stop when it is assumed to decelerate from the current position Q1b at a predetermined deceleration (for example, 0.1 G) as the second estimated stop position Q2b. The predetermined deceleration may be constant or may be a deceleration estimated from the behavior of the detected second preceding vehicle V2b. In addition, when the second preceding vehicle V2b actually starts deceleration, the detected deceleration of the second preceding vehicle V2b may be used.

Alternatively, the second estimated stop position Q2b can be calculated from the driving scene of the vehicle V1 and the second preceding vehicle V2b. For example, if it is known from the map information 3 and the detection results of the vehicle information detection device 4 that an intersection exists ahead of the vehicle V1 on the driving route, and the detection results of the detection device 1 such as an imaging device and the environment recognition device 5 are used to detect that the traffic light at the intersection is presenting a stop signal to the vehicle V1, it is estimated that the second preceding vehicle V2b will stop in front of the stop line, and the second estimated stop position Q2b is calculated.

Alternatively or in addition, the second estimated stop position Q2b may be calculated when the current vehicle speed of the detected second preceding vehicle V2b is equal to or lower than a predetermined vehicle speed. For example, when the second preceding vehicle V2b is traveling at high speed, the second estimated stop position Q2b of the second preceding vehicle V2b will be located away from the host vehicle V1, and it is considered that the host vehicle V1 can secure a distance to travel in order to change lanes from the host lane L1 to the adjacent lane L2. The predetermined vehicle speed can be set to an appropriate value that can secure a distance to travel in order to change lanes from the host vehicle V1 to the adjacent lane L2, based on the relationship between the vehicle speed and the vehicle braking distance.

In addition, when a plurality of second preceding vehicles are detected by the detection device 1 such as an imaging device and a distance measuring device, the second estimated stop position Q2b is calculated assuming that the plurality of second preceding vehicles will stop with a predetermined vehicle distance D2. Specifically, assuming that the plurality of second preceding vehicles will decelerate and stop, the stop positions of the plurality of second preceding vehicles are estimated, and the estimated stop position of the second preceding vehicle closest to the vehicle among these estimated stop positions is set as the second estimated stop position Q2b. For example, in the driving scene of FIG. 8A, it is assumed that the other vehicles V3 and V4 are not stopped but are running, and the other vehicles V2b, V3, and V4 are detected as the second preceding vehicles. In this case, the driving support device 100 uses the function of the route calculation unit 160 to estimate the stop positions when the three second preceding vehicles V2b, V3, and V4 are stopped with a predetermined vehicle distance D2, and the second preceding vehicles V2b, V3, and V4 decelerate and stop. Then, the driving support device 100 calculates the estimated stop position of the second leading vehicle V2b, which is the second leading vehicle closest to the vehicle among the three second leading vehicles, as the second estimated stop position Q2b. The predetermined inter-vehicle distance D2 can be set to an appropriate distance that can avoid contact between multiple second leading vehicles.

After calculating the second estimated stop position Q2b, the driving support device 100 uses the function of the drivable area calculation unit 150 to calculate the second area Z2 in which the host vehicle V1 can travel to change lanes using the second estimated stop position Q2b. The second area Z2 shown by the dashed line in FIG. 8A is set to avoid contact between the host vehicle V1 and the second preceding vehicle V2b and the other vehicle V5 that is stopped, which are assumed to stop at the second estimated stop position Q2b. For example, in the driving scene shown in FIG. 8A, the end E1b on the host vehicle lane L1 side ahead of the driving direction of the second area Z2 is set at a position with a predetermined distance from the rear end of the second preceding vehicle V2b, which is assumed to stop at the second estimated stop position Q2b, in order to avoid contact between the rear end of the second preceding vehicle V2b, which is assumed to stop at the second estimated stop position Q2b, and the tip of the host vehicle V1. In addition, the end E2b of the second area Z2 on the adjacent lane L2 side in the forward driving direction is set at a position with a predetermined distance from the rear end of the other vehicle V5 in order to prevent contact between the rear end of the stopped other vehicle V5 and the front end of the host vehicle V1. The predetermined distance can be set to an appropriate value that can prevent contact between the host vehicle V1 and the second preceding vehicle V2b and the other vehicle V5.

[Generation of second trajectory T2]
8B, after calculating the second area Z2, the driving support device 100 sets the position where the lane change is completed in the second area Z2 in the adjacent lane L2 as the second lane change completion position P2b by the function of the route calculation unit 160. The second lane change completion position P2b can be set to an appropriate position where the host vehicle V1 can change lanes with stable behavior as long as it is within the second area Z2. Then, the driving support device 100 generates a second trajectory T2 along which the host vehicle V1 travels from the current position P1 to the second lane change completion position P2b by the function of the route calculation unit 160. When the second lane change completion position P2b is set to the position shown in FIG. 8B, the driving support device 100 generates, for example, the second trajectory T2 shown in FIG. 8B by the function of the route calculation unit 160. After generating the second trajectory T2, the driving assistance device 100, through the function of the driving behavior control unit 170, uses the vehicle control device 200 to operate the drive mechanism 210, which is an actuator such as a drive actuator and a braking actuator, and begins assisting the host vehicle V1 in changing lanes along the second trajectory T2.

The second trajectory T2 generated by the driving support device 100 can be a driving trajectory in which the host vehicle V1 enters the adjacent lane L2 completely by the time the host vehicle V1 reaches the position E3b of the adjacent lane L2 by setting the second lane change completion position P2b behind the position E3b of the adjacent lane L2 adjacent to the end E1b of the second area Z2 in the host lane L1 in the forward driving direction. In the second embodiment, the host vehicle V1 entering the adjacent lane L2 completely means that the entire body of the host vehicle V1 is included in the adjacent lane L2 when the host vehicle V1 is viewed from above. In addition to this, or instead of this, the second trajectory T2 generated by the driving support device 100 can be a driving trajectory in which the host vehicle V1 enters the adjacent lane L2 completely by the time the host vehicle V1 reaches a position a predetermined distance behind the position E3b of the adjacent lane L2 in the driving direction. The predetermined distance can be set to an appropriate position where the host vehicle V1 can change lanes with stable behavior.

In addition, when the driving support device 100 generates the second trajectory T2 by the function of the route calculation unit 160, the shorter the distance between the current position P1 of the vehicle V1 and the second lane change completion position P2b, the closer the position of the vehicle V1 to start autonomous steering control on the second trajectory T2. In the case of the second trajectory T2 shown in FIG. 8B, the vehicle V1 starts steering control to the right from position S1b, changes the steering direction from right to left at position S2b, completes steering control at position S3b, and returns the steering wheel to a neutral position. In the driving scene shown in FIG. 8B, if the second lane change completion position P2b is set to a position further back in the driving direction than the position shown in FIG. 8B (i.e., a position closer to the current position P1), the position S1b at which autonomous steering control to the right is started on the second trajectory T2 is set to a position further back in the driving direction than the position shown in FIG. 8B (i.e., a position closer to the current position P1).

In addition to this, or instead of this, when generating the second trajectory T2 by the function of the route calculation unit 160, the driving support device 100 may set the distance from the position S1b where the steering control of the autonomous control is started to the position S3b where the steering control is completed to the same distance as the distance required from the start to the completion of the steering control of the autonomous control of the lane change when the host vehicle V1 changes lanes from the host vehicle lane L1 to the adjacent lane L2 when the second preceding vehicle V2b is not detected. For example, in the driving trajectory Ty generated when the second preceding vehicle V2b is not detected as shown in FIG. 11C, the host vehicle V1 starts steering control to the right from position S1y, changes the steering direction from the right to the left at position S2y, completes steering control at position S3y, and stops at position P2y. The driving support device 100 sets the distance from position S1b where autonomous steering control starts to position S3b where steering control ends on the second trajectory T2 shown in FIG. 8B to the same distance as the distance from position S1y where autonomous steering control starts to position S3y where steering control ends on the driving trajectory Ty. In order to set the distance from position S1b to position S3b to the same distance from position S1y to position S3y, the driving support device 100 adjusts the distance from the current position P1 to position S1b where autonomous steering control starts on the second trajectory T2, for example, by setting position S1b.

In addition to this, or instead of this, when generating the first trajectory T1 by the function of the route calculation unit 160, the driving support device 100 may set the distance from the position S1b where the steering control of the autonomous control of the lane change is started to the position S3b where the steering control is completed to a distance greater than or equal to the distance required to generate the second trajectory T2 having a curvature where the centrifugal force generated in the host vehicle V1 when changing lanes is less than a predetermined value in order to make the centrifugal force generated in the host vehicle V1 when changing lanes less than a predetermined value. For example, the driving support device 100 can ensure the distance required to generate the second trajectory T2 having the curvature by setting the distance of the straight section from the current position P1 to the position S1b where the steering control of the autonomous control is started in the second trajectory T2 to be short. The predetermined value of the centrifugal force can be set to an appropriate value that does not cause discomfort to the occupants of the host vehicle V1 and allows the host vehicle V1 to change lanes with stable behavior.

[Calculation process of second area Z2]
Next, the autonomous control process for lane change according to the second embodiment will be described with reference to Figures 9 and 10. Figures 9 and 10 are flowcharts showing the autonomous control process in the processor 10 of this embodiment. Note that the autonomous control process described below is executed at predetermined time intervals by the driving assistance device 100 of this embodiment.

Figure 9 is an example of a subroutine of step S6 shown in Figure 2 according to the second embodiment. When calculating the second area Z2 in which the host vehicle V1 can travel in order to change lanes from the host lane L1 to the adjacent lane L2, step S6 performs processing, for example, according to the procedure shown in Figure 9.

In step S61b, the processor 10 uses the function of the route calculation unit 160 to determine whether or not the host vehicle V1 needs to change lanes from the host lane L1 to the adjacent lane L2 in order for the host vehicle V1 to travel along the travel route set in step S4 of FIG. 2 and the driving plan set in step S5. If it is determined that a lane change from the host lane L1 to the adjacent lane L2 is not necessary (step S61b: No), the process proceeds to step S65b. On the other hand, if it is determined that a lane change from the host lane L1 to the adjacent lane L2 is necessary (step S61b: Yes), the process proceeds to step S62b.

In step S62b, the processor 10 uses the detection device 1, the environment recognition device 5, and the object recognition device 6 through the functions of the path calculation unit 160 to determine whether or not a second preceding vehicle V2b of the host vehicle V1 traveling in the host vehicle lane L1 is present. If the second preceding vehicle V2b is not detected, it is determined that the second preceding vehicle V2b is not present (step S62b: No) and the process proceeds to step S65b. On the other hand, if the second preceding vehicle V2b is detected, it is determined that the second preceding vehicle V2b is present (step S62b: Yes) and the process proceeds to step S63b.

In step S63b, the processor 10 uses the function of the route calculation unit 160 to calculate a second estimated stopping position Q2b when the second preceding vehicle V2b decelerates and stops. In the following step S64b, the processor 10 uses the function of the route calculation unit 160 to calculate a second area Z2 in which the host vehicle V1 can travel in order to change lanes from the host lane L1 to the adjacent lane L2. After calculating the second area Z2 as the drivable area in step S64b, the process proceeds to step S7 in FIG. 2, where the processor 10 uses the function of the route calculation unit 160 to calculate a second trajectory T2, which is a target driving route, for the second area Z2.

On the other hand, when the process proceeds from step S61b or step S62b to step S65b, the processor 10 calculates a drivable area that satisfies the predetermined conditions for the driving route set in step S4 and the driving plan set in step S5. Then, after calculating the drivable area in step S65b, the process proceeds to step S7 in FIG. 2, where the processor 10 uses the function of the route calculation unit 160 to calculate a target driving route for the drivable area in accordance with the predetermined conditions.

[Generation process of second locus T2]
Fig. 10 is an example of a subroutine according to the second embodiment of step S7 shown in Fig. 2. When generating a second trajectory T2 along which the host vehicle V1 travels when changing lanes from the host lane L1 to the adjacent lane L2, step S7 performs processing, for example, according to the procedure shown in Fig. 10.

In step S71b, the processor 10 uses the function of the path calculation unit 160 to set the position where the lane change of the host vehicle V1 from the host lane L1 to the adjacent lane L2 is completed within the second area Z2 as the second lane change completion position P2b. In the following step S72b, the processor 10 uses the function of the path calculation unit 160 to generate a second trajectory T2 that moves from the current position P1 of the host vehicle V1 to the second lane change completion position P2b.

After calculating the second trajectory T2 as the target driving route in step S72b, the process proceeds to step S8 in FIG. 2, where the processor 10 uses the function of the driving behavior control unit 170 to calculate the target vehicle speed and the target vehicle speed profile when the host vehicle V1 drives along the second trajectory T2. In the following step S9, the processor 10 uses the function of the driving behavior control unit 170 to autonomously control the driving operation of the host vehicle V1 using the vehicle control device 200.

[Embodiments of the invention]
As described above, according to the vehicle driving assistance method and assistance device of this embodiment, in driving assistance of a vehicle that autonomously controls a lane change from an own lane L1 in which the own vehicle V1 is traveling to an adjacent lane L2 of the own lane L1, a first preceding vehicle V2a traveling on the adjacent lane L2 in front of the own vehicle V1 is detected, and when the first preceding vehicle V2a is detected, a first estimated stop position Q2a, which is a stop position when it is estimated that the first preceding vehicle V2a will decelerate and stop, is calculated before starting the autonomous control of the lane change, and Using the first estimated stop position Q2a, a first area Z1 on the own lane L1 and the adjacent lane L2 in which the own vehicle V1 can travel to change lanes to the adjacent lane L2 behind the first preceding vehicle V2a is calculated, a position where the lane change is completed within the first area Z1 is set as a first lane change completion position P2a, a first trajectory T1 which is a travel trajectory for completing the lane change by the first lane change completion position P2a is generated, and after the first trajectory T1 is generated, autonomous control of lane change along the first trajectory T1 is started. As a result, since the first estimated stop position Q2a is calculated before the autonomous control of lane change from the own lane L1 to the adjacent lane L2 is started, and the autonomous control of lane change is started after the first trajectory T1 taking the first estimated stop position Q2a into consideration is generated, it is possible to prepare in advance for the possibility that the first preceding vehicle V2a will decelerate and stop, and it is possible to ensure a travel distance required for the own vehicle V1 to change lanes from the own lane L1 to the adjacent lane L2. In addition, even if the first preceding vehicle V2a in the adjacent lane L2 stops at the first estimated stopping position Q2a, the lane change can be completed without the host vehicle V1 changing lanes in an incomplete posture due to an inability to secure a sufficient inter-vehicle distance from the first preceding vehicle V2a, and it is possible to suppress the host vehicle V1 from encountering a driving scene in which correction of the first trajectory T1 is required in the middle of changing lanes. As a result, the behavior of the host vehicle V1 during the lane change is stabilized, and it is possible to prevent the host vehicle V1 from stopping at a position P3x that straddles the host vehicle L1 and the adjacent lane L2.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the first trajectory T1 is a driving trajectory that allows the host vehicle V1 to enter the adjacent lane L2 completely before reaching position E3a of the adjacent lane L2 adjacent to the forward end E1a of the first area Z1 in the host lane L1 in the driving direction. This makes it possible to secure a driving distance for correcting the stopping posture of the host vehicle V1 at the first lane change completion position P2a after the host vehicle V1 enters the adjacent lane L2, and to stop the host vehicle V1 in a stable posture at the first lane change completion position P2a.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the first trajectory T1 is a driving trajectory that the host vehicle V1 enters the adjacent lane L2 from position E3a of the adjacent lane L2 adjacent to the end E1a of the first area Z1 in the host lane L1 in the forward driving direction before reaching a position a predetermined distance behind in the driving direction. This makes it possible to secure a driving distance for correcting the stopping posture of the host vehicle V1 at the first lane change completion position P2a after the host vehicle V1 enters the adjacent lane L2, and to stop the host vehicle V1 in a stable posture at the first lane change completion position P2a.

In addition, according to the vehicle driving support method and support device of this embodiment, after starting autonomous control of lane change along the first trajectory T1, the first stop position Q3a, which is the stop position of the first preceding vehicle V2a, is detected, and using the first stop position Q3a, it is determined whether the host vehicle V1 completes the lane change at the first lane change completion position P2a. If it is determined that the lane change is not completed at the first lane change completion position P2a, the position P3a at which the host vehicle V1 stops is calculated using the first stop position Q3a, and the first trajectory T1 is corrected so that the host vehicle V1 enters the adjacent lane L2 at the position P3a at which the host vehicle stops. As a result, even if the first preceding vehicle V2a stops at the stop position Q3a behind the first estimated stop position Q2a in the driving direction, the lane change can be completed without changing lanes in an incomplete posture because the vehicle distance from the stopped first preceding vehicle V2a cannot be secured. As a result, the behavior of the vehicle V1 during lane change is stabilized, and the vehicle V1 can be prevented from stopping at position P3a that straddles the vehicle's lane L1 and adjacent lane L2.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the shorter the distance between the current position P1 of the host vehicle V1 and the first lane change completion position P2a on the first trajectory T1, the closer the position S1a at which steering control of the autonomous lane change control is started is set to a position that is closer to the current position P1 of the host vehicle V1. This makes it possible to ensure a sufficient distance for the host vehicle V1 to travel in order to change lanes, and to prevent the host vehicle V1 from changing lanes with unstable behavior.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the distance from position S1a where steering control of the autonomous lane change control is started to position S3a where steering control is completed is set to the same distance as the distance required from start to completion of steering control of the autonomous lane change control when the host vehicle V1 changes lanes from the host lane L1 to the adjacent lane L2 in the case where the first preceding vehicle V2a is not detected. This makes it possible to ensure a sufficient distance for the host vehicle V1 to travel in order to change lanes, and to prevent the host vehicle V1 from changing lanes with unstable behavior.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the distance from position S1a where steering control of the autonomous lane change control is started to position S3a where steering control is completed is set to be equal to or greater than the distance required to generate a first trajectory T1 with a curvature that makes the centrifugal force generated in the host vehicle V1 less than a predetermined value when changing lanes. This allows the host vehicle V1 to change lanes with stable behavior without causing discomfort to the occupants of the host vehicle V1.

In addition, according to the vehicle driving support method and support device of this embodiment, when multiple first leading vehicles V2a are detected, the multiple first leading vehicles V2a are assumed to stop with a predetermined inter-vehicle distance D1, and the stopping positions of the multiple first leading vehicles V2a when the multiple first leading vehicles V2a decelerate and stop are estimated, and the estimated stopping position of the first leading vehicle V2a that is closest to the host vehicle V1 among the multiple first leading vehicles V2a is set as the first estimated stopping position Q2a. As a result, when multiple first leading vehicles V2a are detected, an accurate first estimated stopping position Q2a can be calculated.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, in driving assistance for a vehicle that autonomously controls lane change from the own lane L1 in which the own vehicle V1 is traveling to an adjacent lane L2 of the own lane L1, a second preceding vehicle V2b traveling on the own lane L1 in front of the own vehicle V1 is detected, and when the second preceding vehicle V2b is detected, a second estimated stop position Q2b, which is the stop position when it is estimated that the second preceding vehicle V2b will decelerate and stop, is set before starting autonomous control of the lane change. and using the second estimated stop position Q2b, calculate a second area Z2 on the own lane L1 and the adjacent lane L2 in which the own vehicle V1 can travel to change lanes to the adjacent lane L2, set a position in the second area Z2 where the lane change is completed as a second lane change completion position P2b, generate a second trajectory T2 which is a travel trajectory for completing the lane change by the second lane change completion position P2b, and after generating the second trajectory T2, start autonomous control of lane change along the second trajectory T2. As a result, in particular, the second estimated stop position Q2b is calculated before starting autonomous control of lane change from the own lane L1 to the adjacent lane L2, and the autonomous control of lane change is started after generating the second trajectory T2 taking the second estimated stop position Q2b into consideration, so that it is possible to prepare in advance for the possibility that the second preceding vehicle V2b will decelerate and stop, and it is possible to ensure a travel distance required for the own vehicle V1 to change lanes from the own lane L1 to the adjacent lane L2. In addition, even if the second preceding vehicle V2b in the own lane L1 stops at the second estimated stop position Q2b, the lane change can be completed without the vehicle changing in an incomplete position due to an inability to secure a sufficient distance from the second preceding vehicle V2b, and the vehicle can be prevented from encountering a driving scene in which the second trajectory T2 needs to be corrected in the middle of the lane change. As a result, the behavior of the own vehicle V1 during the lane change is stabilized, and the own vehicle V1 can be prevented from stopping at a position P3y that straddles the own lane L1 and the adjacent lane L2.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the second trajectory T2 is a driving trajectory that allows the host vehicle V1 to enter the adjacent lane L2 completely before reaching position E3b of the adjacent lane L2 adjacent to the forward end E1b of the second area Z2 in the host lane L1 in the driving direction. This makes it possible to secure a driving distance for correcting the stopping posture of the host vehicle V1 at the second lane change completion position P2b after the host vehicle V1 enters the adjacent lane L2, and to stop the host vehicle V1 in a stable posture at the second lane change completion position P2b.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the second trajectory T2 is a driving trajectory that the host vehicle V1 enters the adjacent lane L2 completely before it reaches a position a predetermined distance behind position E3b of the adjacent lane L2 adjacent to the end E1b of the second area Z2 in the host lane L1 in the driving direction. This makes it possible to secure a driving distance for correcting the stopping posture of the host vehicle V1 at the second lane change completion position P2b after the host vehicle V1 enters the adjacent lane L2, and to stop the host vehicle V1 in a stable posture at the second lane change completion position P2b.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the shorter the distance between the current position P1 of the host vehicle V1 and the second lane change completion position P2b on the second trajectory T2, the closer the position S1b at which steering control of the autonomous lane change control is started is set. This makes it possible to ensure a sufficient distance for the host vehicle V1 to travel in order to change lanes, and to prevent the host vehicle V1 from changing lanes with unstable behavior.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the distance from position S1b where steering control of the autonomous lane change control is started to position S3b where steering control is completed is set to the same distance as the distance required from the start to the completion of steering control of the autonomous lane change control when the host vehicle V1 changes lanes from the host lane L1 to the adjacent lane L2 in the case where the second preceding vehicle V2b is not detected. This makes it possible to ensure a sufficient distance for the host vehicle V1 to travel in order to change lanes, and to prevent the host vehicle V1 from changing lanes with unstable behavior.

In addition, according to the vehicle driving assistance method and assistance device of this embodiment, the distance from position S1b where steering control of the autonomous lane change control is started to position S3b where steering control is completed is set to be equal to or greater than the distance required to generate a second trajectory T2 with a curvature that makes the centrifugal force generated in the host vehicle V1 less than a predetermined value when changing lanes. This allows the host vehicle V1 to change lanes with stable behavior without causing discomfort to the occupants of the host vehicle V1.

In addition, according to the vehicle driving support method and support device of this embodiment, when multiple second leading vehicles V2b are detected, the multiple second leading vehicles V2b are assumed to stop with a predetermined inter-vehicle distance D2, and the stopping positions of the multiple second leading vehicles V2b when the multiple second leading vehicles V2b decelerate and stop are estimated, and the estimated stopping position of the second leading vehicle V2b that is closest to the host vehicle V1 among the multiple second leading vehicles V2b is set as the second estimated stopping position Q2b. As a result, when multiple second leading vehicles V2b are detected, an accurate second estimated stopping position Q2b can be calculated.

REFERENCE SIGNS LIST 1000 Driving support system 1 Detection device 2 Navigation device 3 Map information 4 Vehicle information detection device 5 Environment recognition device 6 Object recognition device 100 Driving support device 10 Processor 11 CPU
12...ROM
13...RAM
Reference Signs List 110: Output device 111: Communication device 120: Destination setting unit 130: Route planning unit 140: Driving planning unit 150: Driving area calculation unit 160: Route calculation unit 170: Driving behavior control unit 200: Vehicle control device 210: Driving mechanism 211...Communication device D1, D2...Vehicle distance E1a...End E1b on the side of the own lane in the driving direction of the first region...End E1x on the side of the own lane in the driving direction of the second region...End E1y on the side of the own lane in the driving direction of the region Zx...End E2a on the side of the own lane in the driving direction of the region Zy...End E2b on the side of the adjacent lane in the driving direction of the first region...End E2x on the side of the adjacent lane in the driving direction of the region Zx...End E2y on the side of the adjacent lane in the driving direction of the region Zy...Position E3b of the adjacent lane adjacent to end E1a...Position L1 of the adjacent lane adjacent to end E1b...Own lane L2...Adjacent lane O...Obstacle P1, P1a...Current position (own vehicle)
P2a: first lane change completion position P2b: second lane change completion position P2x, P2y: position where lane change is completed P3a: position where the host vehicle stops P3x: position where the host vehicle stops (comparative example)
P3y: Position where the vehicle stops (comparison example)
P4a: new first lane change completion position Q1a, Q1x: current position (first preceding vehicle)
Q1b, Q1y: current position (second preceding vehicle)
Q2a...first estimated stop position Q2b...second estimated stop position Q3a...first stop position S1a, S1b, S1x, S1y...positions where steering control is started S2a, S2b, S2x, S2y...positions where the steering direction is changed from right to left S3a, S3b, S3x, S3y...positions where steering control is completed T1, T1a...first trajectory T2...second trajectory Tx, Ty...trajectory (comparative example)
V1: own vehicle V2a: first preceding vehicle V2b: second preceding vehicle V3, V4, V5: other vehicles Z1: first region Z2: second region Zx, Zy: region (comparative example)

Claims (8)

A vehicle driving support method for autonomously controlling a lane change from a lane in which a vehicle is traveling to an adjacent lane of the vehicle, comprising:
Detecting a first preceding vehicle traveling on the adjacent lane ahead of the host vehicle;
When the first preceding vehicle is detected, a first estimated stop position, which is a stop position when it is estimated that the first preceding vehicle will decelerate and stop, is calculated before starting the autonomous control of the lane change;
using the first estimated stop position, calculating a first area on the own lane and the adjacent lane in which the own vehicle can travel in order to change lanes to the adjacent lane at a position behind the first preceding vehicle;
A position where the lane change is completed within the first area is set as a first lane change completion position;
generating a first trajectory which is a travel trajectory for completing the lane change by the first lane change completion position;
After generating the first trajectory, starting an autonomous control of a lane change along the first trajectory;
After starting autonomous control of lane change along the first trajectory, a first stop position that is a stop position of the first preceding vehicle is detected;
Using the first stop position, it is determined whether or not the host vehicle completes a lane change at the first lane change completion position;
When it is determined that the lane change is not completed at the first lane change completion position, a position where the host vehicle will stop is calculated using the first stop position;
The vehicle driving support method includes correcting the first trajectory so that the host vehicle enters the adjacent lane at a position where the host vehicle stops . The method according to claim 1, wherein the first trajectory is a travel trajectory in which the host vehicle enters the adjacent lane before reaching a position of the adjacent lane adjacent to a forward end of the first region of the host lane in the travel direction. The method according to claim 1 or 2, wherein the first trajectory is a travel trajectory in which the host vehicle enters the adjacent lane from a position of the adjacent lane adjacent to the forward end of the first region of the host lane in the travel direction until the host vehicle reaches a position a predetermined distance behind the adjacent lane in the travel direction. The method according to any one of claims 1 to 3, wherein the shorter the distance between the current position of the vehicle and the first lane change completion position on the first trajectory, the closer the position to the current position of the vehicle is to set a position at which to start steering control of the autonomous lane change control. 5. The method according to claim 4, wherein the distance from the position where steering control of the autonomous control of lane change is started to the position where steering control is completed is set to the same distance as the distance required from the start to the completion of steering control of the autonomous control of lane change when the vehicle changes lanes from the vehicle's own lane to the adjacent lane when the first preceding vehicle is not detected. The method according to claim 4 or 5, wherein the distance from the position where steering control of the autonomous control of lane change is started to the position where steering control is completed is set to be equal to or greater than the distance required to generate the first trajectory having a curvature such that the centrifugal force generated in the vehicle when changing lanes is less than a predetermined value . The method according to any one of claims 1 to 6, wherein, when a plurality of the first leading vehicles are detected, the plurality of first leading vehicles are assumed to stop with a predetermined inter-vehicle distance therebetween, and stopping positions of the plurality of the first leading vehicles are estimated when the plurality of the first leading vehicles decelerate and stop, and the estimated stopping position of the first leading vehicle that is closest to the host vehicle among the plurality of the first leading vehicles is set as the first estimated stopping position. 1. A vehicle driving assistance device including a processor for autonomously controlling a lane change from a lane in which a vehicle is traveling to an adjacent lane of the vehicle,
The processor,
Detecting a first preceding vehicle traveling on the adjacent lane ahead of the host vehicle;
When the first preceding vehicle is detected, a first estimated stop position, which is a stop position when it is estimated that the first preceding vehicle will decelerate and stop, is calculated before starting the autonomous control of the lane change;
using the first estimated stop position, calculating a first area on the own lane and the adjacent lane in which the own vehicle can travel in order to change lanes to the adjacent lane at a position behind the first preceding vehicle;
A position where the lane change is completed within the first area is set as a first lane change completion position;
generating a first trajectory which is a travel trajectory for completing the lane change by the first lane change completion position;
After generating the first trajectory, starting an autonomous control of a lane change along the first trajectory;
After starting autonomous control of lane change along the first trajectory, a first stop position that is a stop position of the first preceding vehicle is detected;
Using the first stop position, it is determined whether or not the host vehicle completes a lane change at the first lane change completion position;
When it is determined that the lane change is not completed at the first lane change completion position, a position where the host vehicle will stop is calculated using the first stop position;
A vehicle driving assistance device that corrects the first trajectory so that the host vehicle enters the adjacent lane at a position where the host vehicle stops .

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