JP2002337714A - Automatic steering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To control a vehicle so that its rear does not protrude from an inner lane during traveling on a curved road in an automatic steering device for retaining traveling of the vehicle within a lane. SOLUTION: A steering actuator 5 is controlled by determining a relative position between the vehicle and the lane detected by a lane detecting part 1, and determining a target position within the lane by a calculating part 3 from an offset direction and amount determined in proportion to a direction and radius of curvature of the curved road detected by the lane detecting part 1 or a curved road detecting part 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic steering system, and more particularly to an automatic steering system for a vehicle to keep a vehicle in a lane.

[0002]

2. Description of the Related Art Such an automatic steering system is provided with a lane detecting section for detecting a lane in which a vehicle travels. As the lane detecting section, a section that visually detects a lane segment using a camera or the like, a marker row composed of a magnet or a radio transmitter is laid in the lane, and the marker row is detected by a magnetic sensor or a radio antenna. Things, etc. are generally known.

Normally, it is considered desirable to travel in the center of the lane, so in the case of the above-described lane detector, the center of the lane width is controlled as the position in the target lane of the automatic steering system. In the case of the above-described lane detection unit, a marker row is laid at the center of the lane width as a target lane position, and the automatic steering device controls the target lane position as a target lane position.

As a result, in any of the above-described lane detecting sections, control is performed by setting the center of the lane width as the position in the target lane of the automatic steering system.

[0005]

As described above, if the control is always performed by setting the center in the lane as the position in the target lane of the automatic steering system, a problem as shown in FIG. 1 (1) occurs. That is, usually, the lane detecting unit 1 is installed at the center of the front part of the vehicle 10, and as described above, control is performed by the automatic steering device so that the lane detecting unit 1 matches the lane width center position CL. However, since the automatic steering control is performed without considering the inner wheel difference, the rear portion of the vehicle 10 protrudes from the left lane (inside lane) LL of the curved road on the curved road as illustrated.

[0006] Since this problem occurs in a vehicle having a long wheelbase, it becomes a serious problem particularly in a large vehicle. SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an automatic steering device for controlling a vehicle to keep in a lane so that the rear of the vehicle does not protrude from an inner lane while traveling on a curved road.

[0007]

In order to achieve the above object, an automatic steering apparatus according to the present invention comprises a lane detecting section, a curve road detecting section, and a lane detecting means for detecting a lane between a vehicle and a vehicle. A calculating unit for determining a relative position and determining an offset direction and an amount according to a direction and a radius of curvature of the curved road detected by the curved road detecting unit to determine a position of the relative position in the target lane; And an actuator for performing steering control based on the inside position.

That is, in the present invention, the arithmetic unit obtains a relative position between the lane and the vehicle detected by the lane detecting unit (for example, a lane width center position, a sectioned lane position, or a vehicle reference position). At the same time, the calculation unit obtains an offset direction and an offset amount for correction according to the direction and the radius of curvature of the curved road detected by the curved road detecting unit.

Further, the arithmetic section corrects the relative position based on the offset direction and the offset amount thus obtained, and sets the corrected relative position as a position in the target lane. The actuator performs steering control based on the position in the target lane determined by the calculation unit.

In this case, the lane detecting section may be a single unit that also serves as a curved road detecting section. In addition, the calculation unit can increase the offset amount as the radius of curvature is smaller. As described above, in the present invention, the position in the target lane of the automatic steering on the curve road corresponds to the curve road. For example, when traveling on the right curve road, the position in the target lane is corrected to the left by the offset amount, and the left curve road is corrected. In the case of traveling, the position in the target lane is corrected to the right by the offset amount.

Therefore, as shown in FIG. 1 (2), for example, when the front center position of the vehicle 10 on which the lane detecting unit 1 is installed is set as the vehicle reference position, this vehicle reference position is a relative position. The vehicle is offset from the lane width center position CL or the section lane position by the offset amount q, thereby avoiding a state in which the rear portion of the vehicle 10 protrudes from the left lane LL.

[0012]

FIG. 2 shows the configuration of an embodiment of the automatic steering apparatus according to the present invention. The automatic steering device according to this embodiment includes a lane detecting section 1, a curve road detecting section 2, a calculating section 3, and a steering actuator 4.

The lane detecting section 1 outputs information relating to the relative position of the lane detected on the basis of the own vehicle.
A known device that can be configured by a combination of a camera and an image processing device or a combination of a lane marker sensor and a signal processing device may be used.

The curve road detector 2 receives, for example, a combination of a camera and an image processing device (which can also be used as the lane detector 1), a vehicle yaw rate sensor, and curve road information from the road infrastructure. A known device such as a navigation device that obtains curved road information from GPS and map information can be used.

The calculation unit 3 includes an input unit 31 that reads lane information from the lane detection unit 1 and information on a curve road from the curve road detection unit 2, and calculates an automatic steering control using the output signal of the input unit 31. A CPU 32 for making judgments, a RAM 33 used by the CPU 32 for calculations and the like, a ROM 34 for storing control programs and control parameters, an output unit 35 for driving the steering actuator 4 according to output data obtained by the CPU 32, and a vehicle. A power supply unit 36 for supplying necessary power to these units from a power supply.

The steering actuator 4 may be a known device that automatically operates the steered wheels (not shown) of the vehicle based on the output from the output unit 35. FIG. 3 shows a flow of a control program stored in the ROM 34 in the arithmetic unit 3 shown in FIG. 2. Hereinafter, the operation of the embodiment of FIG. 2 will be described with reference to FIG. Note that this flowchart is started at predetermined time intervals, and describes only a part related to control of the control device, but omits initial processing when hardware such as a CPU is activated.

First, the CPU 32 reads the lane information of the lane detecting section 1 and the curve road information of the curved road detecting section 2 via the input section 31 (step S1). In this case, the lane information from the lane detecting unit 1 is information relating to the relative position of the lane detected with reference to the center line of the vehicle in the left-right direction. For detection,
Marker row position information). In addition, the curved road detector 2
The curved road information is information on the curved road direction and the radius of curvature of the traveling road.

Next, the CPU 32 calculates a lane width center position based on the lane information read in step S1. in this case,
If the lane information of lane detector 1 is lane information,
As shown in the figure, the left lane LL and the right lane RL (Fig.
Normally, the center of the lane width is set as the lane width center position CL when the marker row information is used.

Next, a curve direction is determined from the curve road information (step S3). If the road is a left curve road, the process proceeds to step S4. Ask for. This offset amount q
Is the vehicle wheelbase, tread, curve radius of curvature r
, And a value stored in the ROM 34 in advance may be read using the curve radius of curvature r as a parameter.

The radius of curvature r of the curve can be obtained as follows. When a combination of a camera and an image processing device is used as the lane detecting unit 1, since the front lane is detected by the camera, the lane is calculated from the detected lane.

When a combination of a lane marker sensor for detecting a marker row and a signal processing device is used as the lane detecting unit 1, the curve curvature radius r is calculated by the separately provided curve road detecting unit 2 as described above. What is necessary is just to detect. And
The offset q with respect to the curve radius of curvature r is set such that the smaller the radius of curvature r, the larger the offset q.

In this manner, the target in-lane position can be determined by adding the offset amount q obtained in steps S4 and S5 to the lane width center position CL calculated in step S2 (step S6). . Further, the offset amount obtained for the left curve road in step S4 acts to shift the target lane position to the right side, and in the case of the right curve road shown in step S5, the target lane position is shifted to the left. Since it acts to approach, the position in the target lane calculated in step S6 is
Since the reference is based on the center line of the vehicle in the left-right direction, the result is as follows.

(A) Target lane position = 0: The target lane position is on the center line of the vehicle in the left-right direction. (b) Target lane position> 0: The target lane position is on the right side of the vehicle center line in the left-right direction. (c) Target lane position <0: The target lane position is on the left side of the vehicle center line in the left-right direction.

It is determined whether the position in the target lane thus determined corresponds to any of the above cases (step S7). That is, when the position in the target lane = 0 (a),
Since the position in the target lane exists on the center line of the own vehicle in the left-right direction, in step S8, control is performed so that the steering actuator 4 is held neutral.

When the position in the target lane <0 (b),
Since the position in the target lane is on the left side of the center line of the host vehicle in the left-right direction, in step S9, the steering actuator 4 is turned left. Furthermore, when the position in the target lane is greater than 0 (c),
Since the position in the target lane is on the right side of the center line of the host vehicle in the left-right direction, in step S10, the steering actuator 4 performs right turning control.

In the above embodiment, the offset amount q is added to the lane width center position CL, but the position of the own vehicle and the position of the lane are relative positions. The same operation as described above can be realized even when the specific position of the own vehicle is relatively determined as the lane width center position) and the offset amount is added thereto.

[0027]

As described above, according to the automatic steering system of the present invention, the relative position between the lane detected by the lane detecting section and the vehicle is determined, and the lane detecting section or the curved road detecting section is used. The arithmetic unit is configured to determine the position of the relative position in the target lane and control the steering actuator based on the detected direction of the curved road and the offset direction and the amount determined according to the radius of curvature. As a result, a state in which the rear portion of the vehicle protrudes from the lane can be avoided, and the vehicle can be safely operated.

[Brief description of the drawings]

FIG. 1 is a schematic plan view for explaining an operational difference between an automatic steering device according to the present invention and a conventional technology.

FIG. 2 is a block diagram showing one embodiment of the automatic steering device according to the present invention.

FIG. 3 is a flowchart showing a control program used in the embodiment of the automatic steering device according to the present invention shown in FIG. 2;

[Explanation of symbols]

 1 Lane detecting section 2 Curve road detecting section 3 Computing section 4 Steering actuator 10 Vehicle CL Center lane width RL Right lane lane LL Left lane lane In the figures, the same reference numerals indicate the same or corresponding parts.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3D032 CC20 DA33 DA88 EB04 5H180 AA01 CC04 CC12 CC24 FF05 FF22 FF27

Claims (4)

[Claims] 1. A lane detector, a curved road detector, a relative position between a vehicle and a lane detected by the lane detector, and a direction and a radius of curvature of the curved road detected by the curved road detector. A calculation unit that determines a position in the target lane of the relative position by obtaining an offset direction and an amount according to the following: an actuator that performs steering control based on the position in the target lane. Steering gear. 2. The automatic steering system according to claim 1, wherein the lane detecting section is a single unit that also serves as the curve road detecting section. 3. The automatic steering apparatus according to claim 1, wherein the calculating section increases the correction offset amount as the radius of curvature decreases. 4. The automatic steering apparatus according to claim 1, wherein the calculation unit sets the relative position to a lane width center position, a segmented lane position, or a vehicle reference position.