Vehicle driving control method and driving control device

Abstract

To provide a vehicle travel control method and a travel control device capable of recognizing a lane marker after changing lanes when changing lanes through autonomous travel control.SOLUTION: A vehicle travel control method which executes autonomous lane change control from a lane L1 on which a vehicle is currently traveling to a target lane L2: detects a travel state of an own vehicle V1; estimates a shape of a road on which the own vehicle is currently traveling on the basis of lateral lane marker information to be detected at a side of the own vehicle; generates a target trajectory when executing the autonomous lane change control on the basis of a start instruction through the autonomous lane change control; and generates a control command value for the autonomous lane change control on the basis of the detected travel state of the own vehicle, the estimated shape of the road and the generated target trajectory.SELECTED DRAWING: Figure 6

Description

[Technical field]

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

[0002] A conventional method for recognizing road information is known in which lane markers for the lane in which the vehicle is traveling are detected, and then lane markers and lane widths for lanes adjacent to this lane are detected, and the lane marker that pairs with the nearby lane marker for the lane after the lane change is estimated based on lane markers common to both the lane before and after the lane change, and the lane width of the lane after the lane change (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-134664 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the above-mentioned conventional road information recognition method, when estimating the lane marker of the lane after a lane change, if a closer lane marker cannot be detected, the corresponding distant lane marker cannot be estimated either.

[0005] The problem to be solved by the present invention is to provide a vehicle driving control method and driving control device that are capable of recognizing lane markers after a lane change when changing lanes under autonomous driving control. [Means for solving the problem]

[0006] The present invention solves the above problem by estimating the shape of the road on which the vehicle is currently traveling based on lateral lane marker information detected on the side of the vehicle, and generating a control command value for autonomous lane change control based on the estimated road shape, the detected traveling state of the vehicle, and the generated target trajectory. Effect of the Invention

[0007] According to the present invention, when changing lanes under autonomous driving control, it is possible to recognize lane markers after the lane change. [Brief description of the drawings]

[0008] [Figure 1] 1 is a block diagram showing an embodiment of a vehicle cruise control device according to the present invention; [Diagram 2] 2 is a front view showing a part of the input device of FIG. 1. [Diagram 3] 2 is a plan view showing an example of lane change control of the driving control device of FIG. 1. [Figure 4] 2 is a plan view showing an example of mounting a front camera, a side camera, and a rear camera included in the sensor of FIG. 1. [Diagram 5] 1A and 1B are plan views showing an example of lane change control using a forward camera. [Figure 6] 2 is a block diagram showing an example of a lane change control unit included in the control device of FIG. 1. [Figure 7] 7 is a diagram illustrating an example of processing executed by a lane change target trajectory generating unit in FIG. 6. [Figure 8] 1A and 1B are plan views showing an example of lane change control using a front camera and a side camera, respectively. [Figure 9] 7 is a diagram illustrating an example of processing executed by a road curvature estimation unit in FIG. 6; [Figure 10] 7 is a diagram illustrating an example of processing executed by a first follow-up command value generating section and a second follow-up command value generating section in FIG. 6. FIG. [Figure 11] 7 is a flowchart showing an example of a control process executed by the lane change control unit of FIG. 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Configuration of the driving control device Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a block diagram showing the configuration of a vehicle cruise control device 1 according to this embodiment. The cruise control device 1 of this embodiment is also an embodiment for carrying out a vehicle cruise control method according to the present invention.

[0010] 1, the driving control device 1 of this embodiment includes a sensor 11, a vehicle position detection device 12, a map database 13, an in-vehicle device 14, a navigation device 15, a presentation device 16, an input device 17, a drive control device 18, and a control device 19. These devices are connected, for example, by a CAN (Controller Area Network) or other in-vehicle LAN, and can transmit and receive information to and from each other.

[0011] The sensor 11 detects the traveling state of the vehicle. For example, the sensor 11 may be a front camera that captures an image in front of the vehicle, a side camera that captures an image of the left and right sides of the vehicle, a rear camera that captures an image of the rear of the vehicle, a front radar that detects an obstacle in front of the vehicle, a rear radar that detects an obstacle behind the vehicle, a side radar that detects an obstacle on the left and right sides of the vehicle, a vehicle speed sensor that detects the vehicle speed of the vehicle, a touch sensor (capacitive sensor) that detects whether the driver is holding the steering wheel, and an in-vehicle camera that captures an image of the driver. The sensor 11 may be configured to use one of the above-mentioned multiple sensors, or may be configured to use a combination of two or more types of sensors. The detection result of the sensor 11 is output to the control device 19 at a predetermined time interval.

[0012] The vehicle position detection device 12 includes a GPS unit, a gyro sensor, a vehicle speed sensor, and the like. The vehicle position detection device 12 detects radio waves transmitted from a plurality of satellite communications by the GPS unit, and periodically acquires position information of a target vehicle (the vehicle itself). The vehicle position detection device 12 also detects the current position of the target vehicle based on the acquired position information of the target vehicle, angle change information acquired from the gyro sensor, and vehicle speed acquired from the vehicle speed sensor. The position information of the target vehicle detected by the vehicle position detection device 12 is output to the control device 19 at predetermined time intervals.

[0013] The map database 13 is a memory that stores three-dimensional high-precision map information including position information of various facilities and specific points and is accessible from the control device 19. The three-dimensional high-precision map information is three-dimensional map information based on road shapes detected when an actual road is traveled using a data acquisition vehicle. The three-dimensional high-precision map information is map information in which detailed and highly accurate position information such as curved roads and the magnitude of the curve (e.g., curvature or curvature radius), junctions, branching points, toll gates, and positions where the number of lanes decreases is associated as three-dimensional information along with the map information. However, the map information stored in the map database of the present invention is not limited to only three-dimensional high-precision map information, and may be other map information.

[0014] The in-vehicle devices 14 are various devices mounted on the vehicle and are operated by the driver. Examples of such in-vehicle devices include a steering wheel, an accelerator pedal, a brake pedal, a turn signal, wipers, lights, a horn, and other specific switches. When the in-vehicle devices 14 are operated by the driver, they output operation information to the control device 19.

[0015] The navigation device 15 acquires the current position information of the vehicle from the vehicle position detection device 12, and displays the vehicle's position on a display or the like by superimposing it on map information for guidance. The navigation device 15 also has a navigation function that, when the driver inputs a destination, calculates a route to the destination and guides the driver along the set route. With this navigation function, the navigation device 15 displays the route to the destination on the map on the display, and notifies the driver of recommended driving behavior along the route by voice or the like.

[0016] The presentation device 16 includes various displays such as a display provided in the navigation device 15, a display built into a rearview mirror, a display built into a meter section, a head-up display projected on the windshield, etc. The presentation device 16 also includes devices other than displays such as a speaker of an audio device, a seat device with a vibrator embedded therein, etc. The presentation device 16 notifies the driver of various presentation information according to the control of the control device 19.

[0017] The input device 17 is, for example, a button switch that allows input by manual operation by the driver, a touch panel arranged on a display screen, or a microphone that allows input by the driver's voice. In this embodiment, the driver can input setting information for the presentation information presented by the presentation device 16 by operating the input device 17. Fig. 2 is a front view showing a part of the input device 17 of this embodiment, and shows an example consisting of a group of button switches arranged on the spokes of a steering wheel, etc.

[0018] The illustrated input device 17 is a button switch used to set ON / OFF, etc., of the autonomous driving control function (autonomous speed control function and autonomous steering control function) equipped in the control device 19. Details of the autonomous driving control function including the autonomous speed control function and the autonomous steering control function will be described later. The input device 17 of this embodiment includes a main switch 171, a resume / accelerate switch 172, a set / coast switch 173, a cancel switch 174, a vehicle distance adjustment switch 175, and a lane change assist switch 176.

[0019] The main switch 171 is a switch for turning on / off the power supply of the system that realizes the autonomous speed control function and the autonomous steering control function of the control device 19. The resume / accelerate switch 172 is a switch for performing a resume operation such as restarting the autonomous speed control function at the set speed before turning off the autonomous speed control function once and then turning it off, or restarting the autonomous speed control function by the control device 19 after following a preceding vehicle (another vehicle traveling ahead in the same lane as the host vehicle. The same applies hereinafter in this specification) and accelerating the set speed. The set / coast switch 173 is a switch for performing a set operation to start the autonomous speed control function at the traveling speed and a coast operation to lower the set speed. The cancel switch 174 is a switch for turning off the autonomous speed control function. The vehicle distance adjustment switch 175 is a switch for setting the vehicle distance from the preceding vehicle, and is a switch for selecting one of multiple settings such as short distance, medium distance, and long distance. The lane change assistance switch 176 is a switch for accepting the start of a lane change when the control device 19 confirms with the driver that the lane change will be started. After accepting the start of a lane change, the lane change assistance switch 176 can be pressed for longer than a predetermined time to cancel the acceptance of the lane change suggestion made by the control device 19.

[0020] In addition to the button switches shown in FIG. 2, a turn signal lever of a turn signal or other switches of the in-vehicle device 14 can be used as the input device 17. For example, when the control device 19 suggests whether or not to change lanes by autonomous control, the driver can turn on the turn signal switch to input consent or permission to the lane change. Also, when the control device 19 suggests whether or not to change lanes by autonomous control, the driver can operate the turn signal lever to change lanes in the direction in which the turn signal lever is operated, rather than the proposed lane change. The setting information input by the input device 17 is output to the control device 19.

[0021] The drive control device 18 controls the running of the host vehicle in various ways. For example, when the host vehicle runs at a constant speed at a set speed due to the autonomous speed control function, the drive control device 18 controls the operation of the drive mechanism (including the operation of the internal combustion engine in an engine vehicle, the operation of the driving motor in an electric vehicle system, and the torque distribution between the internal combustion engine and the driving motor in a hybrid vehicle) and the brake operation in order to accelerate and decelerate the host vehicle to the set speed and to maintain the running speed. In addition, when the host vehicle runs following a preceding vehicle due to the autonomous speed control function, the drive control device 18 controls the operation of the drive mechanism and the brake operation to achieve the acceleration / deceleration and running speed so that the distance between the host vehicle and the preceding vehicle is constant.

[0022] Further, the drive control device 18 performs steering control of the host vehicle by controlling the operation of the steering actuator in addition to the operation control of the drive mechanism and the brake by the autonomous steering control function. For example, when lane keeping control is performed by the autonomous steering control function, the drive control device 18 detects lane markers of the host lane (the lane in which the host vehicle is traveling. The same applies hereinafter in the present specification) and controls the traveling position of the host vehicle in the width direction so that the host vehicle travels at a predetermined position within the host lane. Furthermore, when lane change assistance is performed by a lane change assistance function described later, the drive control device 18 controls the traveling position of the host vehicle in the width direction so that the host vehicle changes lanes. Furthermore, when right / left turn assistance is performed by the autonomous steering control function, the drive control device 18 performs driving control to turn right or left at an intersection or the like. Note that the drive control device 18 controls the traveling of the host vehicle according to an instruction from the control device 19 described later. Other known methods may also be used as the driving control method by the drive control device 18.

[0023] The control device 19 includes a ROM (Read Only Memory) that stores a program for controlling the traveling of the vehicle, a CPU (Central Processing Unit) that executes the program stored in the ROM, and a RAM (Random Access Memory) that functions as an accessible storage device. Note that, as the operating circuit, an MPU (Micro Processing Unit), a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), etc. can be used instead of or in addition to the CPU (Central Processing Unit).

[0024] <Functions realized by the control device 19> The control device 19 executes a program stored in the ROM by the CPU, thereby realizing a driving information acquisition function for acquiring information about the driving state of the vehicle, a driving scene determination function for determining the driving scene of the vehicle, and an autonomous driving control function for autonomously controlling the driving speed and / or steering of the vehicle. Each function of the control device 19 will be described below.

[0025] The driving information acquisition function of the control device 19 is a function for the control device 19 to acquire driving information related to the driving state of the vehicle. For example, the control device 19 acquires image information of the outside of the vehicle captured by the front camera, rear camera, and side camera of the sensor 11 as driving information. The control device 19 also acquires detection results by the front radar, rear radar, and side radar as driving information. Furthermore, the control device 19 acquires vehicle speed information of the vehicle detected by the vehicle speed sensor of the sensor 11, attitude angle and yaw rate of the vehicle detected by a gyro sensor, image information of the driver's face captured by an in-vehicle camera, and the like as driving information.

[0026] Furthermore, the control device 19 acquires current position information of the vehicle as driving information from the vehicle position detection device 12. The control device 19 also acquires a set destination and a route to the destination as driving information from the navigation device 15. The control device 19 also acquires position information such as curved roads and the magnitude of the curve (e.g., curvature or curvature radius), merging points, branching points, toll booths, and positions where the number of lanes is reduced as driving information from the map database 13. In addition, the control device 19 acquires operation information of the in-vehicle device 14 by the driver from the in-vehicle device 14 as driving information. The above is the driving information acquisition function realized by the control device 19.

[0027] The driving scene determination function of the control device 19 is a function for determining the driving scene in which the host vehicle is traveling by referring to a table stored in the ROM of the control device 19. In the table stored in the ROM of the control device 19, driving scenes suitable for, for example, lane changing and overtaking and their determination conditions are stored for each driving scene. The control device 19 refers to the table stored in the ROM to determine whether the driving scene of the host vehicle is suitable for, for example, lane changing and overtaking.

[0028] For example, four conditions are set as conditions for determining a "scene of catching up with a preceding vehicle", namely, "there is a preceding vehicle ahead", "the speed of the preceding vehicle is less than the set speed of the vehicle", "the vehicle reaches the preceding vehicle within a predetermined time", and "the direction of lane change does not meet the lane change prohibition condition". In this case, the control device 19 determines whether the host vehicle satisfies the above conditions based on, for example, the detection results of the front camera and the front radar included in the sensor 11, the vehicle speed of the host vehicle detected by the vehicle speed sensor, and the position information of the host vehicle by the host vehicle position detection device 12. If the above conditions are satisfied, the control device 19 determines that the host vehicle is in a "scene of catching up with a preceding vehicle". The above is the driving scene determination function realized by the control device 19.

[0029] The autonomous driving control function of the control device 19 is a function for the control device 19 to autonomously control the driving of the vehicle without relying on the driver's operation. The autonomous driving control function of the control device 19 includes an autonomous speed control function that autonomously controls the driving speed of the vehicle and an autonomous steering control function that autonomously controls the steering of the vehicle. Note that autonomous control without relying on the driver's operation also includes the driver performing some operations. In addition, the autonomous speed control function and the autonomous steering control function may be functions independent of each other, or may be functions related to each other. The autonomous speed control function and the autonomous steering control function of this embodiment will be described below.

[0030] The autonomous speed control function is a function that, when a preceding vehicle is detected, follows the preceding vehicle while controlling the vehicle distance so as to maintain a vehicle distance according to the vehicle speed with the vehicle speed set by the driver as the upper limit, and when a preceding vehicle is not detected, drives at a constant speed at the vehicle speed set by the driver. The former is also called vehicle distance control, and the latter is called constant speed control. The autonomous speed control function may include a function that detects the speed limit of the road being traveled from a road sign by the sensor 11, or obtains the speed limit from the map information in the map database 13, and automatically sets the speed limit to the set vehicle speed.

[0031] To activate the autonomous speed control function, the driver first operates the resume / accelerate switch 172 or the set / coast switch 173 of the input device 17 shown in FIG. 2 to input a desired driving speed. For example, if the driver presses the set / coast switch 173 while the vehicle is traveling at 70 km / h, the current driving speed is set as is. However, if the driver's desired speed is 80 km / h, the driver can press the resume / accelerate switch 172 multiple times to increase the set speed. The "+" mark on the resume / accelerate switch 172 indicates that the switch increases the set value. Conversely, if the driver's desired speed is 60 km / h, the driver can press the set / coast switch 173 multiple times to decrease the set speed. The "-" mark on the set / coast switch 173 indicates that the switch decreases the set value. The driver can adjust the desired distance by operating the distance adjustment switch 175 of the input device 17 shown in FIG. 2, and can select one of a number of settings, such as short distance, medium distance, or long distance.

[0032] Constant speed control, which drives the vehicle at a constant speed set by the driver, is executed when the forward radar of the sensor 11 or the like detects that there is no preceding vehicle ahead in the vehicle's own lane. In constant speed control, the drive control device 18 controls the operation of the drive mechanisms such as the engine and brakes while feeding back vehicle speed data from the vehicle speed sensor so as to maintain the set driving speed.

[0033] The vehicle distance control, which follows the preceding vehicle while performing the vehicle distance control, is executed when the forward radar of the sensor 11 detects the presence of a preceding vehicle ahead of the vehicle in the vehicle's lane. In the vehicle distance control, the drive control device 18 controls the operation of the drive mechanism such as the engine and the brake while feeding back the vehicle distance data detected by the forward radar so as to maintain the set vehicle distance with the set travel speed as the upper limit. If the preceding vehicle stops while traveling under the vehicle distance control, the vehicle stops following the preceding vehicle. Also, if the preceding vehicle starts to move within, for example, 30 seconds after the vehicle stops, the vehicle also starts to move and starts to follow the preceding vehicle under the vehicle distance control again. If the vehicle stops for more than 30 seconds, the vehicle does not start automatically even if the preceding vehicle starts to move, and if the resume / accelerate switch 172 is pressed or the accelerator pedal is depressed after the preceding vehicle starts to move, the vehicle starts to follow the preceding vehicle under the vehicle distance control again.

[0034] On the other hand, the autonomous steering control function is a function for controlling the operation of the steering actuator to execute steering control of the vehicle. The autonomous steering control function of this embodiment includes: (1) a lane keeping function (lane width direction maintaining function) that controls the steering to drive, for example, near the center of the lane and assists the driver in steering operation; (2) a lane change assist function that controls the steering when the driver operates the turn signal lever and assists the steering operation required for lane change; (3) an overtaking assist function that, when a vehicle slower than a set vehicle speed is detected ahead, asks the driver through a display whether to perform an overtaking operation, and when the driver operates an acceptance switch, controls the steering and assists the overtaking operation; and (4) a route driving assist function that, when the driver has set a destination in a navigation device or the like, asks the driver through a display whether to perform a lane change when the lane change point required for driving according to the route is reached, and controls the steering and assists the lane change when the driver operates an acceptance switch. When autonomous steering control is executed, autonomous speed control is also executed at the same time, but speed control may be executed by the driver's accelerator / brake operation.

[0035] Here, the lane change assist function of the autonomous steering control function will be described. In addition to the lane change assist, autonomous speed control is also executed at the same time. FIG. 3 is a plan view showing an example of lane change control (lane change assist function) executed by the control device 19 of this embodiment. As shown in FIG. 3, when the driver operates the turn signal lever of the vehicle V1, the control device 19 turns on the turn signal, and starts the lane change operation LCP (Lane Change Process, which refers to a series of processes for autonomous lane change) when a preset lane change start condition is satisfied. The control device 19 judges whether the lane change start condition is satisfied based on various driving information acquired by the sensor 11. The lane change start condition is not particularly limited, but may be exemplified as follows: (1) lane keeping mode, (2) the driver is holding the steering wheel, (3) the vehicle is traveling at a speed of 60 km / h or more, (4) there is a lane in the direction of lane change, (5) there is space in the lane to which the lane is to be changed for lane change, (6) the type of lane marker indicates that lane change is possible, (7) the curvature radius of the road is 250 m or more, and (8) the driver has operated the turn signal lever within 1 second. Note that when the control device 19 determines that the lane change start condition is met by the lane change assistance function, even without the driver's instruction, it may suggest to the driver to change lanes by notifying the driver through the presentation device 16.

[0036] When the lane change start condition is satisfied, the control device 19 starts a lane change operation LCP. As shown in FIG. 3, the lane change operation LCP of this embodiment includes a lateral movement in which the vehicle V1 moves in the lane L1 toward the adjacent lane L2, and a lane change manipulation (LCM) in which the vehicle V1 moves from the lane L1 to the adjacent lane L2 across a lane marker. While the lane change operation LCP is being performed, the control device 19 presents information indicating that the lane change is being performed by autonomous control to the driver via the presentation device 16, and calls for the driver to pay attention to the surroundings. When the lane change maneuver LCM is completed, the control device 19 turns off the direction indicator and starts execution of a lane keeping function in the adjacent lane L2. In addition, the lane change operation LCP refers to the period from when the turn signal is turned on to when it is turned off by operating the turn signal lever, and the lane change maneuver LCM refers to the period from when the vehicle V1 starts to step on the boundary line between the vehicle's own lane L1 and the adjacent lane L2 to when it finishes stepping on it.

[0037] Now, when executing a lane change using the lane change assist function of the autonomous steering control function, the control device 19 needs to recognize the position of the own lane and the position of the adjacent lane to which the lane is to be changed and the curvature of the road, and then check whether or not there is a driving space for the own vehicle in this adjacent lane. In this case, if three-dimensional high-precision map information is stored in the map database 13, the position information of the own lane and the adjacent lane and the curvature information of the road are included, but for roads that do not include three-dimensional high-precision map information, it is necessary to capture an image of the actual road using the front camera, side camera, and rear camera of the sensor 11 and recognize the positions of the own lane and the adjacent lane and the curvature of the road.

[0038] 4 is a plan view showing an example of mounting the front camera 111, the side camera 112, and the rear camera 113 included in the sensor 11 of FIG. 1. In the mounting example shown in the figure, the front camera 111 is provided in the center of the front grill or the front bumper of the vehicle V, and captures a front scanning area FA of the vehicle V. The side camera 112 is provided in the door mirror of the vehicle V, and captures each of the left and right side scanning areas SA of the vehicle V. The rear camera 113 is provided in the center of the trunk lid, the back door, or the rear bumper, and captures a rear scanning area BA of the vehicle V. Although not particularly limited, the front scanning area FA captured by the front camera 111, the front scanning area SA captured by the side camera 112, and the rear scanning area BA captured by the rear camera 113 are fan-shaped with a radius of about 10 m.

[0039] FIG. 5 shows an example of autonomous lane change control using the front camera 111, side camera 112, and rear camera 113 thus mounted. FIG. 5(A) is a plan view showing a scene in which the host vehicle V1 changes lanes to an adjacent lane L2 to overtake or pass the preceding vehicle V2 while the host vehicle V1 and the preceding vehicle V2 are traveling in the host lane L1. In this case, the positions of the lane markers LM1 and LM2 in the host lane L1 and the positions of the lane markers LM2 and LM3 in the adjacent lane L2 to be changed to are included in the forward scanning area FA by the front camera 111 even if the attitude (yaw angle) of the host vehicle V1 is changed by the lane change. Therefore, the control device 19 can recognize the position of the host lane L1 and the position of the adjacent lane L2 to be changed to. After recognizing the positions of the host lane L1 and the adjacent lane L2, the front camera 111 can also confirm whether or not there is a driving space for the host vehicle V1 in the adjacent lane L2.

[0040] On the other hand, when the attitude (yaw angle) of the vehicle V1 increases due to lane change as shown in FIG. 5(B), the positions of the lane markers LM1 and LM2 of the vehicle's lane L1 and the positions of the lane markers LM2 and LM3 of the adjacent lane L2 of the lane change destination are no longer included in the forward scanning area FA of the forward camera 111, so the control device 19 cannot recognize the positions of the vehicle's lane L1 and the adjacent lane L2 of the lane change destination. Therefore, the autonomous lane change control is interrupted or stopped, and the driver is forced to switch to manual operation. Such a situation often occurs when the distance between the vehicle V1 and the preceding vehicle V2 is short.

[0041] Therefore, in the vehicle driving control device 1 according to this embodiment, when the lane markers LM1, LM2 of the own lane L1 and the lane markers LM2, LM3 of the adjacent lane L2 to which the lane is to be changed are not included in the forward scanning area FA of the front camera 111, and therefore the autonomous lane change control cannot be continued, the lane markers LM1, LM2 of the own lane L1 and the lane markers LM2, LM3 of the adjacent lane L2 to which the lane is to be changed are recognized using the side camera 112. Hereinafter, an embodiment of lane change control using the front camera 111 and the side camera 112 will be described. FIG. 6 is a block diagram showing an example of a lane change control unit 190 included in the control device 19, and FIGS. 7(A) and 7(B) are plan views showing an example of lane change control using the front camera 111 and the side camera 112, respectively.

[0042] 6, the lane change control unit 190 of this embodiment includes a lane change target trajectory generating section 191, a front lane marker estimating section 192, a first following command value generating section 193, a road curvature estimating section 194, a second following command value generating section 195, and a command value switching section 196, into which signals or information are read from a front camera 111 as a front lane marker detecting section, a side camera 112 (and / or a rear camera 113) as a side lane marker detecting section, and a sensor 11 as a vehicle state detecting section, and further a final command value is output to the drive control device 18. Each section constituting the lane change control unit 190 is depicted for the sake of convenience, and is actually realized by a program stored in a ROM.

[0043] The lane change target trajectory generating unit 191 generates a target trajectory for lane change using a lane change start signal as a trigger. When the lane change is autonomously performed by the driving scene determination function described above or when a lane change command is given by the driver, a lane change start signal is input to the lane change target trajectory generating unit 191. FIG. 7 is a diagram showing an example of the generation process executed by the lane change target trajectory generating unit 191. The upper diagram is a plan view showing a scene in which the vehicle V changes lanes from the start position of lane L1 to the end position of lane L2, and the lower diagram is a diagram showing the target lateral position Y ref and the target attitude angle θ ref The attitude angle θ is a yaw angle with respect to the traveling direction of the vehicle V.

[0044] The lane change target trajectory generating unit 191 stores in advance the distance from the reference start position to the end position and the reference lateral position at this distance, and generates a lane change target trajectory based on these reference distances and reference lateral positions. For example, for the start position to the end position set according to the driving speed, the following distance-target lateral position Y ref As shown in the graph of FIG. 1, a relaxation curve that smoothly connects these start positions and end positions is generated, such as a trigonometric function, a polynomial function, a clothoid curve, a Bezier curve, etc. Also, a target attitude angle θ ref is the distance - target attitude angle θ ref As shown in the graph, distance vs. target lateral position Y ref Target horizontal position Y of the graph ref The lane change target trajectory generating unit 191 calculates the target lateral position Y ref and the target attitude angle θ ref to the first following command value generator 193.

[0045] The front lane marker estimation unit 192 extracts front lane markers from the captured image of the front scanning area FA captured by the front camera 111, which is a front lane marker detection unit, and the captured image of the side scanning area SA captured by the side camera 112 (and / or rear camera 113), which is a side lane marker detection unit, and recognizes the lane markers of the lane in which the vehicle is currently traveling and the lane markers of the adjacent lane to which the vehicle will change lanes. Fig. 8(A) is a plan view showing an example of lane change control using the front camera 111 and the side camera 112. Since the vehicle V1 can capture lane markers LM1, LM2 of the lane L1 in which the vehicle is currently traveling and lane markers LM2, LM3 of the adjacent lane L2 in the forward scanning area FA of the forward camera 111 and the side scanning area SA of the side camera 112, the forward lane marker estimation unit 192 recognizes the lane markers LM1, LM2, L3, calculates the road curvature ρ from the forward lane marker information (i.e., lateral position Y, attitude angle θ) of the recognized forward lane markers LM1, LM2, L3, and outputs this lane marker information Y, θ and the road curvature ρ to the first following command value generation unit 193.

[0046] The side camera 112 (and / or rear camera 113) which is a side lane marker detection unit recognizes the lane markers of the lane in which the host vehicle is currently traveling and the lane markers of the adjacent lane to which the host vehicle will change lanes from the captured image of the side scanning area SA. In Fig. 8(A), the host vehicle V1 can capture the lane markers LM1 and LM2 of the lane L1 in which the host vehicle is currently traveling and the lane markers LM2 and LM3 of the adjacent lane L2 in the side scanning area SA of the side camera 112. The resulting side lane marker information of the side lane markers LM1, LM2, and LM3 (i.e., the lateral position Y and the attitude angle θ) is output to the second following command value generation unit 195 and the road curvature estimation unit 194. However, the lateral lane marker information only refers to the lane markers LM1, LM2, and LM3 detected in the lateral scanning area SA of the host vehicle V1, and not to lane markers detected in the forward area of ​​the adjacent lane L2 into which the host vehicle V1 is about to change lanes. Therefore, the curvature of the road cannot be detected directly from the captured image.

[0047] Therefore, the road curvature estimation unit 194 accumulates over time side lane marker information of lane markers LM1, LM2, LM3 detected in the side scanning area SA of the host vehicle V1 by the side camera 112, calculates the road curvature ρ from the lateral position Y and attitude angle θ of the accumulated side lane marker information and the vehicle speed and yaw rate of the host vehicle V1 detected by the sensor 11, which is a vehicle state detection unit, and outputs this to the first following command value generation unit 193. Fig. 9 is a diagram showing an example of the estimation process in the road curvature estimation unit 194, and lane marker information located behind the vehicle V (lateral position Y and attitude angle θ, shown by white circles in Fig. 9) corresponds to the accumulated side lane marker information.

[0048] The road curvature estimation unit 194 accumulates side lane marker information, which is a past detection result, by dead reckoning using odometry (a method of measuring a path) based on the vehicle speed and yaw rate of the vehicle V. Then, (1) using the accumulated most recent lateral position Y information, function approximation to a polynomial function or the like is performed by regression analysis such as the least squares method, and the road curvature is estimated from this. Alternatively or in addition, (2) using the accumulated most recent attitude angle θ information, an average value of the attitude angle change amount with respect to the distance may be calculated, and the road curvature may be estimated from this. Furthermore, instead or in addition, (3) from the vehicle speed and yaw rate included in the traveling state of the host vehicle V1 detected by the sensor 11, the curvature of the traveling trajectory T of the vehicle V shown in FIG. 9 may be estimated, and the road curvature may be estimated from this. The method (3) of estimating the curvature of the road from the curvature of the driving trajectory of the vehicle V may be adopted only when the function approximation error by the regression analysis (1) above is greater than a predetermined threshold value, or when the variance of the average value of the relative angle change amount (2) above is greater than a predetermined threshold value.

[0049] The first following command value generating unit 193 generates the target lateral position Y ref and target attitude angle θ ref and the lateral position Y sens , attitude angle θ sens , the curvature of the road ρ roadFrom this, a first control command value for lane changing to be actually output to the drive control device 18 is calculated. Fig. 10 is a diagram showing an example of the generation process executed by the first following command value generator 193 and the second following command value generator 195, where the upper diagram is a plan view showing a scene in which the vehicle V changes lanes from the start position of lane L1 to the end position of lane L2, and the lower diagram is a circuit diagram showing an example of a control circuit that compensates for the lateral position Y, attitude angle θ, and road curvature ρ in the scene shown in the upper diagram.

[0050] In the control circuit diagram shown in the lower diagram of FIG. 10, a lateral position compensation unit 197 calculates the target lateral position Y ref and the lateral position Y estimated by the front lane marker estimation unit 192. sens The attitude angle compensation unit 198 calculates the difference ΔY between the target attitude angle θ and the target attitude angle θ , and outputs a lateral position control command value that brings the difference ΔY closer to zero by feedback control. ref and the attitude angle θ estimated by the front lane marker estimation unit 192 sens The road curvature compensation unit 199 calculates the difference Δθ between the road curvature ρ road The first following command value generator 193 adds the target lateral position Y ref and target attitude angle θ ref The road curvature ρ estimated by the front lane marker estimation unit 192 road The first control command value that follows the target trajectory and takes into account the above is output to the drive control device 18.

[0051] The road curvature ρ road When the front lane marker information can be detected by the front camera 111, it is updated successively with the passage of time. However, when the front lane marker information becomes undetectable from a detectable state, the last estimated road curvature ρ road It is more preferable to hold the above-mentioned and use it for generating the first control command value in the first following command value generating unit 193.

[0052] In response to this, the second following command value generating unit 195 generates the target lateral position Y ref and target attitude angle θ ref and the lateral position Y detected by the side camera 112 (and / or the rear camera 113) which is the side lane marker detection unit. sens and attitude angle θ sens and the road curvature ρ estimated by the road curvature estimation unit 194. road 10. In other words, the lateral position compensation unit 197 uses the control circuit diagram shown in the lower diagram of FIG. 10 in the same manner as the first following command value generation unit 193 described above, and calculates the second control command value for lane change to be actually output to the drive control unit 18. ref and the lateral position Y detected by the side camera 112. sens The attitude angle compensation unit 198 calculates the difference ΔY between the target attitude angle θ and the target attitude angle θ , and outputs a lateral position control command value that brings the difference ΔY closer to zero by feedback control. ref and the attitude angle θ detected by the side camera 112 sens The road curvature compensation unit 199 calculates the difference Δθ between the road curvature ρ estimated by the road curvature estimation unit 194 and outputs a control command value for the attitude angle that brings the difference Δθ closer to zero by feedback control. road The second following command value generator 195 adds the target lateral position Y ref and target attitude angle θ ref The road curvature ρ estimated by the road curvature estimation unit 194 road The second control command value that follows the target trajectory and takes into account the above is output to the drive control device 18.

[0053] The command value switching unit 196 selectively switches between the first control command value generated by the first following command value generating unit 193 and the second control command value generated by the second following command value generating unit 195, and outputs either one of them to the drive control device 18. The control command value output to the drive control device 18 may be either the first control command value or the second control command value. However, preferably, the command value switching unit 196 outputs the first control command value of the first following command value generating unit 193 to the drive control device 18 when the forward lane marker information can be detected, that is, when the forward camera 111 can recognize the lateral position, attitude angle, and road curvature of the forward lane marker. On the other hand, when the forward lane marker information cannot be detected, that is, when the forward camera 111 cannot recognize the lateral position, attitude angle, and road curvature of the forward lane marker, the command value switching unit 196 outputs the second control command value of the second following command value generating unit 195 to the drive control device 18.

[0054] Although not particularly limited, when command value switching unit 196 switches between the control command value of first following command value generation unit 193 and the control command value of second following command value generation unit 195, it is preferable that the command value switching unit 196 performs low-pass filter processing on the control command value or executes processing to suppress the amount of change in the control command value over time.

[0055] <Lane change control processing> Next, the lane change control process according to this embodiment will be described with reference to Fig. 11. Fig. 11 is a flowchart showing an example of the lane change control process executed by the control device 19 of this embodiment. The driving control process described below is executed by the control device 19 at a predetermined time interval. In the following, it is assumed that the autonomous driving control function of the control device 19 executes autonomous speed control and autonomous steering control, and performs lane keep control to control the driving position of the host vehicle in the width direction so that the host vehicle drives within the lane at a speed set by the driver.

[0056] In step S1 of Fig. 11, the control device 19 judges whether or not a start signal for lane change control has been input. The control device 19 repeats step S1 until the start signal for lane change control has been input. On the other hand, if the start signal for lane change control has been input, the control device 19 proceeds to step S2.

[0057] When a lane change control start signal is input, in step S2, the control device 19 judges whether or not the lane markers of the lane currently being traveled and the adjacent lane to which the lane is to be changed can be detected by the front camera 111, which is a front lane marker detection unit. For example, in the state shown in FIG. 8(A), the front camera 111 includes the lane markers LM1, LM2, and LM3 of the lanes L1 and L2 in the forward scanning area FA, so it is judged that the front lane marker information can be detected. In contrast, in the state shown in FIG. 8(B) where the attitude angle of the host vehicle V1 has increased, the front camera 111 does not include the lane markers LM1 and LM2 of the lanes L1 and L2 in the forward scanning area FA, so it is judged that the front lane marker information cannot be detected. If it is judged that the front lane marker information can be detected, the process proceeds to step S3, and if it is judged that the front lane marker information cannot be detected, the process proceeds to step S6.

[0058] If it is determined that the forward lane marker information can be detected, in step S3, the first following command value generator 193 generates a first control command value, and in the following step S4, lane change control is executed based on the first control command value.

[0059] On the other hand, when it is determined that the front lane marker information is not detectable as in the state shown in FIG. 8(B), in step S6, it is determined whether the lane markers of the lane currently being traveled and the adjacent lane to which the lane is to be changed are detectable by the side camera 112 (and / or the rear camera 113). In the state shown in FIG. 8(B), the lane markers LM1 and LM2 of the lanes L1 and L2 are not included in the forward scanning area FA of the front camera 111, but the lane markers LM1, LM2, and LM3 of the lanes L1 and L2 are included in the side scanning area SA of the side camera 112, so it is determined that the side lane marker information is detectable. Then, in step S7, the second following command value generator 195 generates a second control command value, and in the following step S4, lane change control is executed by the second control command value. If it is determined in step S6 that the side lane marker information is not detectable, the lane change control is terminated.

[0060] In step S5, it is determined whether or not the lane change is completed, and if not, the process returns to step S2 and the subsequent processes are repeated.

[0061] As described above, according to the vehicle driving control method and driving control device 1 of the present embodiment, the road shape on which the vehicle is currently traveling, specifically the road curvature ρ, is estimated based on the side lane marker information (lateral position Y and attitude angle θ) detected on the side of the vehicle V1, and a control command value for the autonomous lane change control is generated based on the estimated road shape, the target trajectory generated by the start command of the autonomous lane change control, and the detected driving state of the vehicle. This makes it possible to recognize the lane marker after the lane change when changing lanes by the autonomous lane change control. As a result, the autonomous lane change control can be continued even if the forward lane marker information cannot be detected.

[0062] According to the vehicle cruise control method and cruise control device 1 of the present embodiment, the shape of the road on which the vehicle is currently traveling is estimated based on forward lane marker information detected ahead of the vehicle V1, and autonomous lane change control is executed by selectively using a first control command value depending on the road shape estimated based on the forward lane marker information and a second control command value depending on the road shape estimated based on the side lane marker information. This makes it possible to expand the range of lane markers that can be detected around the vehicle V1.

[0063] In addition, according to the vehicle driving control method and driving control device 1 of this embodiment, when forward lane marker information is detectable, autonomous lane change control is executed using a first control command value based on this, and when forward lane marker information is undetectable, autonomous lane change control is executed using a second control command value based on lateral lane marker information, so that autonomous lane change control can be continued even when forward lane marker information is undetectable.

[0064] Furthermore, according to the vehicle driving control method and driving control device 1 of this embodiment, when switching between a first control command value based on forward lane marker information and a second control command value based on side lane marker information, low-pass filter processing of the control command value or processing to suppress the amount of change in the control command value over time is performed, thereby making it possible to suppress sudden fluctuations in the control command value when switching.

[0065] Furthermore, according to the vehicle cruise control method and cruise control device 1 of this embodiment, the road shape estimated based on the forward lane marker information is updated successively over time if the forward lane marker information is detectable, and if the forward lane marker information changes from detectable to undetectable, the last estimated road shape is held and used to generate the first control command value until it becomes detectable. This makes it possible to use the first control command value using the forward lane marker information, which has a high reliability for estimating the road shape, as much as possible.

[0066] In addition, according to the vehicle driving control method and driving control device 1 of this embodiment, the curvature of the road is estimated by performing regression analysis on the position information of the accumulated side lane marker information with a predetermined function, or by calculating the average value of the relative angle change per unit length from the relative angle information of the accumulated side lane marker information, thereby estimating the curvature of the road with high accuracy.

[0067] Furthermore, according to the vehicle driving control method and driving control device 1 of this embodiment, when the function approximation error by regression analysis is greater than a predetermined threshold value or the variance of the average value of the relative angle change amount is greater than a predetermined threshold value, the curvature of the vehicle's driving trajectory is estimated from the vehicle speed and yaw rate included in the detected driving state of the vehicle, and this estimated curvature of the vehicle's driving trajectory is estimated as the curvature of the road, so that the curvature of the road can be estimated as accurately as possible.

[0068] In addition, according to the vehicle driving control method and driving control device 1 of this embodiment, the target trajectory when executing autonomous lane change control is generated so as to smoothly connect the position and posture at which the vehicle starts changing lane and the position and posture at which the vehicle ends changing lane, and the target values ​​for the lateral position and attitude angle when executing autonomous lane change control are generated from the generated target trajectory, so that lane changes can be made along a smooth driving trajectory that provides a comfortable ride.

[0069] Furthermore, according to the vehicle driving control method and driving control device 1 of this embodiment, when the autonomous lane change control is executed to change from the currently traveling lane to a target lane, a lateral position compensation process is executed to reduce the deviation between the target value of the lateral position and the actual lateral position, an attitude angle compensation process is executed to reduce the deviation between the target value of the attitude angle and the actual attitude angle, and an estimated road shape is added, so that the lane can be changed with accurate control. [Explanation of symbols]

[0070] 1...Drive control device 11…Sensor 12...Vehicle position detection device 13…Map database 14…In-vehicle equipment 15. Navigation device 16...Presentation device 17...Input device 18...Drive control device 19...Control device V1: Vehicle V2: Leading vehicle L1: Lane currently being driven L2: adjacent lane

Claims

1. A vehicle driving control method for performing autonomous lane change control from a current lane to a target lane, Detect the driving state of the vehicle, estimating a shape of a road on which the vehicle is currently traveling based on side lane marker information detected on the sides of the vehicle; generating a target trajectory for performing the autonomous lane change control based on a start command of the autonomous lane change control; A vehicle driving control method for generating a control command value for the autonomous lane change control based on the detected driving state of the host vehicle, the estimated road shape, and the generated target trajectory, A vehicle driving control method that selectively uses a first control command value based on a road shape estimated based on forward lane marker information and a second control command value based on a road shape estimated based on side lane marker information to perform the autonomous lane change control.

2. 2. The vehicle driving control method according to claim 1, wherein the lateral lane marker information is information about lane markers that divide lanes of a road, and includes position information of the lane markers and relative angle information of the lane markers with respect to the host vehicle.

3. When the forward lane marker information is detectable, the autonomous lane change control is executed using the first control command value; 3. The vehicle driving control method according to claim 1, wherein when the forward lane marker information cannot be detected, the autonomous lane change control is executed using the second control command value.

4. 4. The vehicle driving control method according to claim 1, wherein, when switching between the first control command value and the second control command value, a low-pass filter process of the control command value or a process of suppressing a time-dependent change amount of the control command value is executed.

5. The road shape estimated based on the forward lane marker information is When the forward lane marker information is detectable, the forward lane marker information is successively updated over time; 5. A vehicle driving control method according to claim 1, wherein, when the forward lane marker information changes from detectable to undetectable, the last estimated road shape is held and used to generate a first control command value until the forward lane marker information becomes detectable.

6. The road shape is a road curvature, 6. The vehicle driving control method according to claim 1, further comprising the step of: estimating a road curvature by performing a regression analysis of position information of the accumulated side lane marker information with a predetermined function.

7. A vehicle driving control method for performing autonomous lane change control from a current lane to a target lane, Detect the driving state of the vehicle, estimating a shape of a road on which the vehicle is currently traveling based on side lane marker information detected on the sides of the vehicle; generating a target trajectory for performing the autonomous lane change control based on a start command of the autonomous lane change control; A vehicle driving control method for generating a control command value for the autonomous lane change control based on the detected driving state of the host vehicle, the estimated road shape, and the generated target trajectory, The road shape is a road curvature, A vehicle driving control method for estimating road curvature by calculating an average value of a relative angle change amount per unit length from the relative angle information of accumulated side lane marker information.

8. A vehicle driving control method for performing autonomous lane change control from a current lane to a target lane, Detect the driving state of the vehicle, estimating a shape of a road on which the vehicle is currently traveling based on side lane marker information detected on the sides of the vehicle; generating a target trajectory for performing the autonomous lane change control based on a start command of the autonomous lane change control; A vehicle driving control method for generating a control command value for the autonomous lane change control based on the detected driving state of the host vehicle, the estimated road shape, and the generated target trajectory, The road shape is a road curvature, The road curvature is estimated by performing a regression analysis of the position information of the accumulated side lane marker information with a predetermined function; estimating a road curvature by calculating an average value of a relative angle change amount per unit length from the relative angle information of the accumulated side lane marker information; estimating a curvature of a travel path of the host vehicle from a vehicle speed and a yaw rate included in the detected travel state of the host vehicle; When the function approximation error by the regression analysis is larger than a predetermined threshold value, or when the variance of the average value of the relative angle change amount is larger than a predetermined threshold value, the curvature of the estimated vehicle travel trajectory is estimated as a road curvature.

9. a target trajectory when performing autonomous lane change control is generated so as to smoothly connect a position and posture at which the host vehicle starts changing a lane and a position and posture at which the host vehicle ends changing a lane; 9. The vehicle driving control method according to claim 1, further comprising generating a target value of a lateral position and a target value of an attitude angle when performing autonomous lane change control from the generated target trajectory.

10. When executing the autonomous lane change control from the current lane to the target lane, A lateral position compensation process is executed to reduce a deviation between the target value of the lateral position and an actual lateral position. Executing an attitude angle compensation process to reduce a deviation between the target value of the attitude angle and an actual attitude angle; The vehicle travel control method according to claim 9, further comprising adding the estimated road shape.

11. A vehicle cruise control device including a processor for executing autonomous lane change control from a current lane to a target lane, The processor, Detect the driving state of the vehicle, estimating a shape of a road on which the vehicle is currently traveling based on side lane marker information detected on the sides of the vehicle; generating a target trajectory for performing the autonomous lane change control based on a start command of the autonomous lane change control; A vehicle driving control device that generates a control command value for the autonomous lane change control based on the detected driving state of the host vehicle, the estimated road shape, and the generated target trajectory, A vehicle driving control device that selectively uses a first control command value based on a road shape estimated based on forward lane marker information and a second control command value based on a road shape estimated based on side lane marker information to perform the autonomous lane change control.

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