Vehicle control device

Abstract

To provide a vehicle control device that can suppress a road from deteriorating.SOLUTION: A vehicle control device according to one embodiment comprises: a target route setting part that sets a target route; an offset amount determining part that determines an amount of offset with respect to the target route; a target route correcting part that generates a corrected target route offset in a lateral direction by the mount of the offset with respect to the target route; and a control part that controls a steering angle of a vehicle so that a vehicle travels along the corrected target route.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle control device. [Background technology]

[0002] There is known a device that controls the steering angle of a vehicle so that the vehicle travels along a target route. For example, Patent Document 1 listed below describes a driving assistance device that corrects the steering angle of the vehicle so as to reduce the lateral error between a target point on a target trajectory and a future travel point of the vehicle, thereby causing the vehicle to travel along a driving lane. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-126077 Summary of the Invention [Problem to be solved by the invention]

[0004] When a driver manually drives a vehicle, the vehicle's driving position varies to a certain extent. On the other hand, when the steering angle is automatically controlled, as in the above-mentioned driving assistance device, the reproducibility of the vehicle's driving position within the lane is high, so the vehicle's driving position is less likely to vary. Therefore, when a large number of vehicles are automatically controlled, they will repeatedly drive in the same position, and road deterioration will progress locally in that position.

[0005] Therefore, an object of the present disclosure is to provide a vehicle control device that can suppress road deterioration. [Means for solving the problem]

[0006] In one aspect, the system includes a target route setting unit that sets a target route, an offset amount determination unit that determines an offset amount for the target route, a target route correction unit that generates a corrected target route that is offset laterally by the offset amount from the target route, and a control unit that controls the steering angle of the vehicle so that the vehicle travels along the corrected target route.

[0007] In this aspect, the vehicle travels along a corrected target route that is offset laterally from the target route by the offset amount. In other words, the vehicle travels at a position deviated from the target route, thereby preventing local deterioration of the road at positions on the target route.

[0008] In one embodiment, the offset amount determination unit may generate random numbers according to a normal distribution with the lateral position of the target route as the mean value, and determine the offset amount based on the random numbers. By determining the offset amount based on random numbers generated according to a normal distribution, the vehicle's traveling position can be made to vary as in manual driving, thereby suppressing road deterioration.

[0009] In one embodiment, the control unit controls the steering angle of the vehicle when the vehicle travels through a specific section so that the vehicle travels along the target route instead of the corrected target route. The specific section may be a section including an intersection, a section under construction, or a section including a narrow road with a lane width narrower than a threshold. In these specific sections, more careful consideration of the lateral position of the vehicle is required for safety. By having the vehicle travel along the target route instead of the corrected target route when traveling through the specific section, driving safety can be ensured. [Effects of the Invention]

[0010] According to one aspect and various embodiments of the present invention, road deterioration can be reduced. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a block diagram showing a functional configuration of a vehicle control device according to an embodiment; [Figure 2] FIG. 10 is a diagram illustrating a corrected target route. [Figure 3] 4 is a flowchart showing a flow of processing by a vehicle control device. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, vehicle control devices according to various embodiments will be described in detail with reference to the drawings. Note that the same or corresponding parts in each drawing will be denoted by the same reference numerals, and duplicate descriptions of the same or corresponding parts will be omitted.

[0013] Fig. 1 is a block diagram showing the functional configuration of a vehicle control device according to an embodiment. The vehicle control device 10 shown in Fig. 1 is mounted on a vehicle 1 and controls the steering angle of the vehicle 1 so that the vehicle 1 travels along a driving lane.

[0014] The vehicle 1 equipped with the vehicle control device 10 is a large vehicle such as a truck, trailer, or bus. However, the vehicle 1 may also be a small vehicle. As shown in FIG. 1, the vehicle 1 includes a camera 2, a GPS (Global Positioning System) receiving unit 3, a map database 4, a steering actuator 5, and the vehicle control device 10.

[0015] The camera 2 captures an image of the area ahead of the vehicle 1. The camera 2 may be a monocular camera or a stereo camera. The stereo camera has two imaging units arranged to reproduce binocular parallax. The imaging information of the stereo camera includes information in the depth direction. The image information captured by the camera 2 is output to the vehicle control device 10.

[0016] The GPS receiver 3 receives signals from three or more GPS satellites to acquire location information indicating the location of the vehicle 1. The location information includes, for example, information regarding latitude and longitude. The GPS receiver 3 outputs the measured location information of the vehicle 1 to the vehicle control device 10. Note that, instead of the GPS receiver 3, the vehicle 1 may be equipped with another device that acquires the location information of the vehicle 1, such as an inertial navigation system.

[0017] The map database 4 is a storage device that stores map information. The map database 4 is configured, for example, by an HDD (Hard disk drive) mounted on the vehicle 1. The map information includes, for example, road position information, information about road shape, information about road construction, and position information about intersections, toll booths, etc. The information about road shape includes, for example, information about lane width, type of road shape (curved section or straight section), and lane curvature. The map database 4 does not have to be mounted on the vehicle 1, but may be located in a facility such as an information processing center that can communicate with the vehicle 1.

[0018] The steering actuator 5 controls the driving of the electric power steering system in response to a control signal from the vehicle control device 10. The steering angle of the vehicle 1 is controlled by controlling the driving of the electric power steering system.

[0019] The vehicle control device 10 is an electronic control unit having a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), CAN (Controller Area Network) communication circuit, etc. The vehicle control device 10 is connected to a network that communicates using, for example, the CAN communication circuit, and is communicatively connected to each component of the vehicle 1. For example, the vehicle control device 10 operates the CAN communication circuit based on a signal output by the CPU to input and output data, stores the data in RAM, loads a program stored in the ROM into the RAM, and executes the program loaded into the RAM, thereby realizing various functions described below. The vehicle control device 10 may be composed of multiple electronic control units.

[0020] The vehicle control device 10 executes steering assist control to control the steering angle of the vehicle 1 so that the vehicle 1 does not deviate from the driving lane. The steering assist control is a control in which the vehicle control device 10 controls the steering to make the vehicle 1 travel along the driving lane without relying on the steering operation of the driver. Note that the vehicle control device 10 may also perform automatic driving control to make the vehicle travel autonomously without relying on the driving operation of the driver.

[0021] As shown in FIG. 1, the vehicle control device 10 has, as its functional configuration, a lane detection unit 11, a target route setting unit 12, an offset amount determination unit 13, a target route correction unit 14, a specific section determination unit 15, and a control unit 16.

[0022] The lane detection unit 11 detects the driving lane ahead of the vehicle 1 based on the image captured by the camera 2. The driving lane is the lane on which the vehicle 1 is traveling. For example, the lane detection unit 11 extracts a pair of lane markings (e.g., white lines) on the left and right sides of the road on which the vehicle 1 is traveling from the image ahead of the vehicle 1 captured by the camera 2, and recognizes the area between the pair of lane markings as the driving lane. Note that the lane detection unit 11 may detect the driving lane based on the position information of the vehicle 1 measured by the GPS receiving unit 3 and the map information stored in the map database 4, without using the image captured by the camera 2.

[0023] The target route setting unit 12 sets a target route that is a target for steering assist control of the vehicle 1. The target route is a trajectory that is set within the driving lane and that the vehicle 1 should travel along. For example, the target route setting unit 12 sets a trajectory that follows the lateral centerline of the driving lane as the target route. The lateral direction is the direction that coincides with the width direction of the driving lane. In other words, the target route is a trajectory that connects points that are equidistant from a pair of left and right lane markings in the lateral direction. The target route setting unit 12 may also set the target route at a position offset from the centerline of the driving lane. For example, when turning right or left at an intersection, it is preferable to travel at a position offset from the centerline of the driving lane, taking into account the influence of inside wheel difference. In such a case, the target route setting unit 12 sets the target route at a position offset from the centerline of the driving lane.

[0024] The offset amount determination unit 13 determines an offset amount relative to the target route set by the target route setting unit 12. The offset amount is the amount of lateral deviation relative to the target route. The offset amount may be a set value or may be determined randomly. For example, the offset amount determination unit 13 may determine the offset amount based on a normal distribution whose average value (peak value) is the lateral position of the target route. More specifically, the offset amount determination unit 13 generates random numbers that follow a normal distribution whose average value is the lateral position of the target route, and determines the offset amount according to the generated random numbers.

[0025] The vehicle control device 10 may be connected to a communication device capable of communicating with a management center or other vehicles, receive information indicating the offset amount from the management center or other vehicles, and determine the offset amount based on the information. For example, if multiple vehicles are equipped with the vehicle control device 10 and the multiple vehicles are traveling in the same lane, the management center may transmit information indicating different offset amounts to the multiple vehicles.

[0026] The target path correction unit 14 corrects the target path set by the target path setting unit 12 to generate a corrected target path. The corrected target path will be described with reference to a specific example shown in FIG. 2. In the example shown in FIG. 2, a pair of left and right lane markings L are provided on the road on which the vehicle 1 is traveling. The target path setting unit 12 sets a target path P1 along the center line of the traveling lane defined by the pair of lane markings L. In this case, the target path correction unit 14 generates a corrected target path P2 by laterally offsetting the target path P1 by the offset amount e determined by the offset amount determination unit 13. In other words, the corrected target path P2 is set at a position shifted in the left-right direction from the center line of the traveling lane by the offset amount e. The corrected target path P2 is set within the traveling lane.

[0027] The specific section determination unit 15 determines whether the vehicle is traveling in a specific section. A specific section is a section among sections that are subject to steering assist control, where the correction of the target route should be canceled. For example, a specific section is a section that includes an intersection, a section under construction, or a section that includes a narrow road. A narrow road is a section where the lane width is narrower than a threshold. Narrow roads include, for example, sections that include toll booths. The specific section determination unit 15 acquires position information of the specific section based on map information stored in the map database 4, for example. Then, the specific section determination unit 15 determines whether the vehicle 1 is traveling in a specific section by comparing the position information of the vehicle 1 measured by the GPS receiver 3 with the position information of the specific section.

[0028] The control unit 16 controls the steering angle of the vehicle 1 so that the vehicle 1 travels along the corrected target path P2. For example, the control unit 16 obtains the amount of lateral deviation between the corrected target path P2 and the center position of the vehicle 1 based on an image captured by the camera 2, and controls the steering angle of the vehicle so that the amount of lateral deviation becomes smaller. For example, when the vehicle 1 travels autonomously to a destination specified by the driver, the lateral position of the vehicle 1 is controlled so that the vehicle 1 travels along the corrected target path P2 from its current position until it arrives at the destination. Note that if the driver sets a new destination after arriving at the destination, the offset amount may be changed to set a new corrected target path P2, and the vehicle 1 may be steered and controlled along the new corrected target path P2.

[0029] By controlling the steering angle of vehicle 1 in this way, vehicle 1 travels at a position deviated left or right from the center line of the travel lane by offset amount e. By having vehicle 1 travel at a position deviated left or right from the center line of the travel lane, lateral variation in the travel position of vehicle 1 occurs, as in manual driving, and localized progression of road deterioration is suppressed.

[0030] When traveling through a specific section that includes an intersection, etc., careful consideration of the lateral position of the vehicle may be required to ensure safety, and in such cases, it may be preferable not to correct the target route. Therefore, when the specific section determination unit 15 determines that the vehicle is traveling through a specific section, the control unit 16 may control the steering angle of the vehicle 1 so that the vehicle travels along the target route P1 instead of the corrected target route P2. In other words, when traveling autonomously from the current location to the destination, the vehicle travels along the target route P1 in the specific section, and along the corrected target route P2 in sections other than the specific section. In this way, by traveling along the target route instead of the corrected target route when the vehicle 1 travels through a specific section, safety can be ensured.

[0031] The flow of processing executed by the vehicle control device 10 will be described below with reference to Fig. 3. Fig. 3 is a flowchart showing the flow of processing by the vehicle control device 10.

[0032] First, the lane detection unit 11 of the vehicle control device 10 detects the driving lane based on an image of the area ahead of the vehicle 1 captured by the camera 2 (step ST1). Next, the target route setting unit 12 sets a target route that is a target for steering assist control of the vehicle 1 (step ST2). For example, the target route setting unit 12 sets a trajectory that follows the center line of the detected pair of left and right lane markings, i.e., the center line of the driving lane, as the target route P1.

[0033] Next, the offset amount determination unit 13 determines an offset amount for the target route set by the target route setting unit 12 (step ST3). For example, the offset amount determination unit 13 determines the offset amount based on a normal distribution with the lateral position of the target route as the average value.

[0034] Next, the target route correction unit 14 corrects the set target route to generate a corrected target route (step ST4). For example, the target route correction unit 14 sets, as the corrected target route, a trajectory in the driving lane obtained by laterally offsetting the target route by the offset amount determined by the offset amount determination unit 13.

[0035] Next, the specific section determination unit 15 determines whether the vehicle 1 is traveling in a specific section (step ST5). For example, the specific section determination unit 15 determines that the vehicle 1 is traveling in a specific section when the vehicle is traveling in a section including an intersection, a section under construction, or a section including a narrow road.

[0036] If it is determined that the vehicle 1 is traveling in a specific section, the control unit 16 controls the steering angle of the vehicle 1 so that the vehicle 1 travels along the pre-correction target route (step ST6). In this case, for example, the vehicle 1 travels along the center line of the travel lane. On the other hand, if it is determined that the vehicle 1 is traveling in a section other than the specific section, the control unit 16 controls the steering angle of the vehicle 1 so that the vehicle 1 travels along the corrected target route (step ST7). In this case, the vehicle 1 travels, for example, at a position deviated to the left or right from the center line of the travel lane.

[0037] As described above, in the vehicle control device 10 of one embodiment, the vehicle travels along a corrected target route that is offset laterally from the target route by the offset amount determined by the offset amount determination unit 13. When the vehicle 1 travels at a position deviated from the target route, localized progression of road deterioration is suppressed. In particular, when multiple vehicles are equipped with the vehicle control device 10 and each vehicle control device 10 randomly determines the offset amount, variations occur in the lateral traveling positions of the multiple vehicles, as in manual driving, and road deterioration can be effectively suppressed.

[0038] The vehicle control device 10 according to various embodiments has been described above, but it is not limited to the above-described embodiments and various modifications can be made within the scope that does not change the gist of the invention.

[0039] For example, the vehicle control device 10 does not necessarily have to include the specific section determination unit 15, and may control the steering angle of the vehicle 1 so that the vehicle 1 travels along the corrected target route regardless of whether the vehicle is traveling through a specific section. Note that the various embodiments described above can be combined to the extent that no contradiction occurs. [Explanation of symbols]

[0040] 1...vehicle, 10...vehicle control device, 12...target route setting unit, 13...offset amount determination unit, 14...target route correction unit, 16...control unit, e...offset amount, P1...target route, P2...corrected target route

Claims

[Claim 1] a target route setting unit that sets a target route; an offset amount determination unit that determines an offset amount relative to the target route; a target path correction unit that generates a corrected target path that is offset laterally by the offset amount relative to the target path; a control unit that controls a steering angle of the vehicle so that the vehicle travels along the corrected target route; Equipped with the offset amount determination unit generates random numbers according to a normal distribution having a mean value corresponding to the position of the target route in the lateral direction, and determines the offset amount based on the random numbers; the control unit controls a steering angle of the vehicle so that the vehicle travels along the target route instead of the corrected target route when the vehicle travels through a specific section; A vehicle control device, wherein the specific section is a section including an intersection or a section under construction.

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