JP2004102447A - Automatic steering apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To safely run a vehicle in a traffic lane with a width being smaller than that of the vehicle in an automatic steering apparatus for keeping vehicle travelling within the lane. <P>SOLUTION: When the width of a traffic lane, where driver's own vehicle is travelling is smaller than that of the vehicle, and also when one of the left and right parts of the travelling lane is closer to a road shoulder than the other part, an arithmetic part 4 decides the position in a target lane, by performing offset for the portion of a prescribed correction amount in the direction opposite to the road shoulder, through the use of traffic lane information base on a lane division line, which is detected by a lane division line detecting part 2. Thus, a steering actuator 5 is controlled in steering, on the basis of the position in the target lane. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an automatic steering device, and more particularly, to an automatic steering device that allows a vehicle to perform traveling in a lane.
[0002]
[Prior art]
Such an automatic steering device is provided with a lane detecting unit that detects a lane in which the vehicle travels. The lane detecting section includes: (1) a section for visually detecting a segmented lane using a camera or the like; and (2) a marker array comprising magnets and radio transmitters is laid in the lane, and this marker array is used as a magnetic sensor. And those detected by a radio wave antenna are generally known.
[0003]
The control by such an automatic steering device will be described with reference to FIG. 1 (1). In general, it is considered desirable to drive in the center of the lane. The lane width center position CL obtained from the detected left-side lane LL and right-side lane RL is controlled as the position in the target lane of the automatic steering system. A marker row is laid at the center position CL of the lane width as a position, and the automatic steering device controls this as a position in the target lane.
[0004]
Accordingly, the vehicle 10 on which the automatic steering control is being performed is controlled such that the vehicle center line CC, which is the center in the left-right direction of the vehicle, matches the in-lane center position CL (state A). That is, when the vehicle center line CC is closer to the left lane LL side as in the state B, the steering to the right is automatically performed. Conversely, when the vehicle center line CC is closer to the right lane RL as in the state C, the steering to the left is automatically performed.
[0005]
As described above, in each of the lane detecting sections (1) and (2), the control is performed by setting the center of the lane width as the position in the target lane of the automatic steering device.
[0006]
[Problems to be solved by the invention]
As described above, if the center in the lane is always controlled as the position in the target lane of the automatic steering device, the following problem occurs particularly in the case of a large vehicle.
FIG. 1 (2) shows a case where the vehicle 10 shown in FIG. 1 (1) is a large vehicle, and the overall width W2 of the vehicle 10 is wider than the lane width W1 of the traveling lane. is there. The state corresponding to the state A is the state D. As described above, when the automatic steering control is performed so that the vehicle center line CC, which is the center in the left and right direction of the host vehicle, coincides with the center position CL in the lane, the same applies. As shown in the state, the left and right sides of the vehicle 10 always protrude left and right by the same width from the left and right lane marking lines LL and RL.
[0007]
When the vehicle 10 travels in such a state, there is a risk that a part of the vehicle 10 protruding to the road shoulder side may come into contact with a roadside workpiece (a sign, a signboard, or the like). In addition, there is a risk that a road shoulder collapses or a wheel loses.
Accordingly, an object of the present invention is to provide an automatic steering system for a vehicle to perform traveling in a lane, so that the vehicle can travel in a lane narrower than the full width of the vehicle more safely.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, when a large vehicle runs on a narrow road, in the above-mentioned state D, for example, assuming that the left lane marking LL side is adjacent to the road shoulder, the lane as shown in the state E It is desirable to offset the position in the target lane to the right from the width center position CL by the offset amount q.
[0009]
From such a viewpoint, the automatic steering device according to the present invention uses a lane marking detection unit that detects a lane marking on the road surface, and lane information based on the lane marking detected by the lane marking detection unit. If the lane width of the lane in which the host vehicle is traveling is smaller than the entire width of the host vehicle and one of the left and right sides of the traveling lane is closer to the shoulder than the other, the offset is offset by a predetermined correction amount in the direction opposite to the shoulder. And an actuator for performing steering control based on the target lane position.
[0010]
That is, in the present invention, the calculation unit determines the position in the target lane by using the lane information based on the lane marking detected by the lane marking detection unit, and the lane width of the lane in which the own vehicle is running is the full width of the own vehicle. If the lane is narrower and one of the left and right lanes of the traveling lane is closer to the road shoulder than the other, a predetermined correction amount is applied in the direction opposite to the road shoulder (for example, a predetermined value is set to a half of the full width of the vehicle). After adding as a margin, the position in the target lane is determined by offsetting by a correction amount obtained by subtracting half of the lane width.
[0011]
The actuator performs steering control based on the position in the target lane determined by the calculation unit.
Therefore, in the present invention, when the lane width of the traveling lane is smaller than the entire width of the vehicle, and only one of the right and left is adjacent to the road shoulder, the vehicle does not protrude to the road shoulder side, It becomes possible to drive more safely in a lane narrower than the full width of the own vehicle.
[0012]
In this case, the arithmetic unit determines that the number of lanes of the traveling road obtained from the lane information detected by the lane marking detection unit is 2, and when the vehicle is traveling in the right lane, the right side of the traveling lane is It is determined that the vehicle is traveling closer to the road shoulder than the left side. If the vehicle is traveling in the left lane, it may be determined that the left side of the traveling lane is closer to the road shoulder than the right side.
[0013]
That is, the calculation unit offsets the position in the target lane as described above only when the number of lanes of the road on which the vehicle is traveling is two.
This is because lane markings are not necessarily set in consideration of the overall width of the passing vehicle, but in the case of a lane design of three or more lanes, it can be assumed that the lane width is sufficiently secured. This is because there is no need to offset the position in the target lane while traveling on a road with three or more lanes.
[0014]
In the case of a road with only one lane, the left and right sides are adjacent to the road shoulder. In this case, it is not desirable to offset the position in the target lane to either the left or right, and the center of the lane width is targeted. It is desirable to perform automatic steering control as a position in the lane. In addition, the automatic steering device according to the present invention further includes a marker row detection unit that detects a marker row installed on a road, and while the marker row detection unit is detecting the marker row, the calculation unit is The position in the target lane may be determined by giving priority to the marker row.
[0015]
This is because the marker row is usually constructed by deciding the lane width assuming the full width of the large vehicle in advance when laying, so when performing the automatic steering control by detecting the marker row, This is because it is considered that no offset is required.
[0016]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 2 shows the configuration of an embodiment of the automatic steering apparatus according to the present invention. The automatic steering apparatus according to this embodiment includes an automatic steering switch 1, a lane marking detection unit 2, a marker row detection unit 3, a calculation unit 4, and a steering actuator 5.
[0017]
The automatic steering switch 1 is a dedicated switch for the driver to instruct the start and release of the automatic steering control by ON / OFF of the switch.
The lane marking detection section 2 and the marker row detection section 3 output information relating to the relative position of the lane detected based on the own vehicle, and each includes a combination of a camera and an image processing device, and a lane marker sensor. A known device that can be configured by a combination with a signal processing device or the like may be used.
[0018]
The calculation unit 4 reads an automatic steering switch signal from the automatic steering switch 1, lane information from the lane marking detection unit 2, and lane information from the marker row detection unit 3, and an output of the input unit 41. CPU 42 for performing calculations and determinations regarding automatic steering control using signals, RAM 43 used by CPU 42 for calculations and the like, ROM 44 for storing control programs and control parameters, and steering actuator 6 according to output data obtained by CPU 42. , And a power supply unit 46 for supplying necessary power from the vehicle power supply to these units.
[0019]
The steering actuator 5 may use a known device that automatically operates the steered wheels (not shown) of the vehicle based on the output from the output unit 45.
FIG. 3 shows the flow of the control program stored in the ROM 44 in the arithmetic unit 4 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 a predetermined time interval, and describes only a portion related to control of the control device, but omits initial processing when hardware such as a CPU is activated.
[0020]
In addition, the positions used in this flowchart are all expressed as "0" at the center line of the host vehicle in the left-right direction, + as the right side of the vehicle, and-as the left side of the vehicle. It is assumed that the lane marking detection unit 2 and the marker row detection unit 3 also express the lane information by setting the center line of the vehicle in the left-right direction to “0”.
[0021]
First, the CPU 42 reads the automatic steering switch signal from the automatic steering switch 1, the lane information from the lane marking detection unit 2, and the lane information from the marker row detection unit 3 via the input unit 41 (step S1).
Next, the CPU 42 confirms ON / OFF of the automatic steering switch 1 based on the automatic steering switch signal read in step S1 (S2). If the automatic steering switch 1 is OFF, the automatic steering control is not performed, so that the steering actuator 5 is set to the non-steering control (S3), and the process ends.
[0022]
If the automatic steering switch 1 is ON in step S2, the CPU 42 determines the presence or absence of a marker row based on the lane information from the marker row detecting unit 3 read in step S1 (S4). If there is a marker row in step S4, the lane width center position is calculated based on the lane information (marker row) from the marker row detecting section 3 (step S5). In this case, the position of the marker row is set as the lane width center position as it is, and “0” is substituted for the offset amount (S6).
[0023]
If there is no marker row in step S4, the lane width is calculated based on the lane information from the lane marking detection unit read in step S1 (S7), and then the lane width center position is calculated (S8). ). In this case, the center of the left lane and the right lane may be calculated as the lane width center position.
[0024]
Next, the lane width obtained in step S7 is compared with a set value T1 corresponding to the entire width of the vehicle (S9). If lane width <set value T1, the lane classification read in step S1 is determined. The number of lanes is calculated based on the lane information from the line detector 2 (S11).
If the number of lanes is 2 in step S11, a deviation that is the absolute value of the left and right offset amounts is obtained (step S12). In this case, the set value T2 is predetermined in order to allow a certain margin on the road shoulder side, and the lane width is calculated as a value obtained by adding the set value T2 to one half of the set value T1 corresponding to the entire width of the vehicle. The value obtained by subtracting one half is used as the deviation.
[0025]
Next, it is determined whether the traveling lane is the right side or the left side of the two lanes (S13). If the lane is on the right side, the sign of the deviation obtained in step S12 is inverted to offset to the left side. Substitute for the offset amount (S14). Conversely, if it is on the left side, the deviation obtained in step S12 is directly substituted for the offset amount to offset to the right side (step S15).
[0026]
If lane width ≧ set value T1 in step S9, and if lane number ≠ 2 in step S11, “0” is substituted for the offset amount (step S15).
After obtaining the offset amount by any one of steps S6, S14, and S15, the CPU 42 calculates the target lane position by adding the offset amount to the lane width center position calculated in step S5 or S8 (step S5). S16).
[0027]
Since the position in the target lane obtained in step S16 is based on the center line of the host vehicle in the left-right direction, the position 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 left side of the center line of the vehicle in the left-right direction.
[0028]
(C) Target lane position> 0: The target lane position is on the right side of the center line of the vehicle 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 S17).
[0029]
That is, when the target lane position = 0 (a), the target lane position is present on the center line of the host vehicle in the left-right direction. Therefore, in step S18, the steering actuator 5 is controlled to be held neutral.
When the target lane position is less than 0 (b), the target lane position is on the left side of the center line of the vehicle in the left-right direction, and thus the steering actuator 5 is turned left in step S19.
[0030]
Further, when the target lane position is greater than 0 (c), since the target lane position is on the right side of the center line of the host vehicle in the left-right direction, the steering actuator 5 is controlled to turn right in step S20.
[0031]
【The invention's effect】
As described above, according to the automatic steering device of the present invention, the arithmetic unit uses the lane information based on the lane marking detected by the lane marking detecting unit, and calculates the lane width of the lane in which the vehicle is traveling. Is narrower than the entire width of the vehicle and one of the left and right of the traveling lane is closer to the road shoulder than the other, offset by a predetermined correction amount in the opposite direction to the road shoulder to determine the position in the target lane, Since the steering actuator is configured to perform steering control based on the position in the target lane, it is possible to more safely travel in a lane narrower than the full width of the host vehicle.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining a position in a target lane in automatic steering control.
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 apparatus according to the present invention shown in FIG. 2;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 automatic steering switch 2 lane marking detection unit 3 marker row detection unit 4 calculation unit 5 steering actuator

Claims (4)

A lane marking detection unit that detects a lane marking on the road surface;
Using the lane information based on the lane marking detected by the lane marking detection unit, the lane width of the lane in which the own vehicle is traveling is smaller than the full width of the own vehicle, and either the left or right of the traveling lane is A calculation unit that determines a target lane position by offsetting by a predetermined correction amount in a direction opposite to the road shoulder when the vehicle is closer to the road shoulder than the other,
An actuator that performs steering control based on the position in the target lane;
An automatic steering device comprising: In claim 1,
The arithmetic unit is configured such that when the number of lanes of the traveling road obtained from the lane information detected by the lane marking detection unit is 2, and when the vehicle is traveling in the right lane, only the right side of the traveling lane is displayed. An automatic steering system characterized by judging that it is adjacent to a road shoulder, and judging that only the left side of the running lane is adjacent to the road shoulder when traveling in the left lane. In claim 1,
It further includes a marker row detection unit that detects a marker row installed on the road,
The automatic steering device, wherein the arithmetic unit determines the position in the target lane while giving priority to the marker row while the marker row detecting unit detects the marker row. In claim 1,
The calculation unit calculates a predetermined correction amount by adding a predetermined value to a half of the entire width of the host vehicle as a margin, and then subtracting a half of the lane width. Steering gear.

Images