JP2001291196A - Device for detecting vehicle position - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle position detecting device capable of detecting that a vehicle position is deviated from a prescribed control range with high precision. SOLUTION: A plurality of magnetic sensors are arranged in the width direction of the vehicle, a level comparator 18 detects whether the output levels of the two prescribed magnetic sensors are equal to or more than a prescribed value or not, a differential arithmetic unit 20 judges whether the output level of the magnetic sensor at the outer side of the vehicle width direction between the two magnetic sensors is larger than the output level of the inner side magnetic sensor or not and an abnormality output is issued when the whole conditions are satisfied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a vehicle position detecting device,
In particular, the present invention relates to an improvement in a vehicle position detection device for detecting an abnormality in a vehicle position.

[0002]

2. Description of the Related Art Heretofore, there has been proposed a technique for detecting lane position in a width direction of a road and detecting lane keeping control by detecting a magnetic flux generated from a magnetic generating means such as a magnet embedded in the road with a magnetic sensor. Have been. For example, Japanese Patent Laid-Open No. 11-
No. 94567 also discloses a technique for detecting lane magnets on a road with a magnetic sensor and performing lane keeping control.

FIG. 5 shows an example of the conventional vehicle position detecting device. In FIG. 5, a magnetic generator 12 is embedded in a road 10. Further, the vehicle 14 has magnetic sensors 16a, 16b, 16c, 16d, and 1d at its bottom for detecting magnetic flux generated by the magnetic generator 12.
6e is provided. The position control of the vehicle during normal traveling is performed such that the detected value of the magnetic flux detected by the magnetic sensor 16c provided at the center position in the width direction of the vehicle 14 is maximized.

When the detection value from the center magnetic sensor 16c cannot be obtained, it is determined that the magnetic sensor is abnormal, and the left magnetic sensors 16a, 16b in the width direction of the vehicle are determined.
The control of the vehicle position is continued by calculating the difference between the detection value of the right side and the detection values of the right side magnetic sensors 16d and 16e.

[0005]

However, in the above-described conventional vehicle position detecting device, it is possible to cope with an abnormality of the magnetic sensor, but when the position of the vehicle deviates from the control range for some reason, There is no disclosure on how to determine this.

The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a vehicle position detecting device capable of detecting with high accuracy that a vehicle position has deviated from a predetermined control range. .

[0007]

To achieve the above object, the present invention relates to a vehicle position detecting device, comprising a plurality of magnetic sensors in a width direction of a vehicle for which lane keeping control is performed.
The output levels of the two predetermined magnetic sensors are equal to or higher than a predetermined value, and the output level of the magnetic sensor outside the vehicle in the width direction of the two magnetic sensors is higher than the output level of the magnetic sensor inside the vehicle in the width direction. When this happens, the vehicle control is determined to be abnormal.

In the above-mentioned vehicle position detecting device, the abnormality determination is performed by calculating a difference between output levels of the two magnetic sensors on an electric circuit.

Further, in the vehicle position detecting device, the output of the electric circuit is used as it is as a trigger signal for a treatment at the time of abnormality.

[0010]

Embodiments of the present invention (hereinafter referred to as embodiments) will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a vehicle position detecting device according to the present invention. In the present embodiment, a plurality of magnetic sensors 16 are provided on the bottom of the vehicle 14, for example, as shown in FIG. These magnetic sensors detect the magnetic flux generated from the magnet generating means 12 such as a magnet, detect the position of the vehicle 14, and perform vehicle position control based on the data.

[0012] Of the plurality of magnetic sensors 16, two predetermined magnetic sensors 16 are selected, and the outputs of the magnetic sensor 16 on the outside and the magnetic sensor 16 on the inside in the width direction of the vehicle are respectively sent to the level comparator 18. Is entered. The outputs of the outer magnetic sensor 16 and the inner magnetic sensor 16 are
It is also input to the difference calculator 20. In the difference calculator 20,
From the output of the inner magnetic sensor 16 to the outer magnetic sensor 16
The operation of subtracting the output of is performed.

First, the two level comparators 18 determine whether or not the output levels of the two predetermined magnetic sensors 16 are each equal to or greater than a predetermined value n. Predetermined value n
This is because the smaller the value, the lower the detection accuracy. Also,
Whether the output level of the magnetic sensor 16 on the outside in the width direction of the vehicle is higher than the output level of the magnetic sensor 16 on the inside,
That is, it is determined whether or not the output of the difference calculator 20 has a negative value. When all of the above conditions are satisfied, the vehicle position detection device according to the present embodiment determines that the vehicle position control is in an abnormal state, and outputs an abnormal output.

FIG. 2 is an operation explanatory diagram of the block diagram shown in FIG. FIG. 2 shows an example in which two magnetic sensors 16 on the outside in the width direction of the vehicle are provided and one magnetic sensor 16 on the inside is provided. When the position of the vehicle 14 is within the normal control range, the inner magnetic sensor 16
Are the highest and the outputs of the two outer magnetic sensors 16 are lower than this. On the other hand, if the position of the vehicle 14 shifts to the right or left due to any cause, the distance between the outer magnetic sensor 16 and the magnetic generation unit 12 on the opposite side to the direction in which the vehicle position shifts becomes shorter. , The output of the outer magnetic sensor 16 increases. Also, the output of the inner magnetic sensor 16 decreases.
When the position of the vehicle 14 shifts by a certain amount in the lateral direction, the output of the inner magnetic sensor 16 and the output of the outer magnetic sensor 16 become the same, and when the position of the vehicle 14 further shifts, the magnitude relationship between the outputs is reversed. This relationship is monitored by the difference calculator 20 shown in FIG. That is, when the output of the difference calculator 20 becomes negative, it means that the output of the outer magnetic sensor 16 which is a condition for the vehicle position detecting device to output an abnormal output is higher than the output of the inner magnetic sensor 16. ing.

As described above, as a condition for the vehicle position detecting device according to the present embodiment to output an abnormal output, the output of the outer magnetic sensor 16 and the output of the inner magnetic sensor 16 are determined by the level comparator 18 shown in FIG. Must also be equal to or greater than the predetermined value n.

As described above, in the vehicle position detecting device according to the present embodiment, the output levels of the two predetermined magnetic sensors 16 are both equal to or higher than the predetermined value n, and
An abnormal output is generated when the output of the inner magnetic sensor 16 becomes higher than the output of the inner magnetic sensor 16, that is, when the output of the outer and inner magnetic sensors shown in FIG. Thus, the range in which the outputs of the outer and inner magnetic sensors 16 have the same value is the control range of the lateral position of the vehicle.

The above-described level comparator 18 and difference calculator 20 can be configured by software, but can also be realized on an electric circuit, that is, by hard logic. When realized on an electric circuit, an operation error of the vehicle position detecting device due to an abnormality of software or the like can be avoided, and high reliability can be secured.

Further, when an abnormal output is output from the vehicle position detecting device, it is preferable that the abnormal output be used to directly carry out a measure when the vehicle position is abnormal, for example, the operation of an emergency brake. In this way, the abnormal output of the vehicle position detecting device is used as it is as a trigger signal for a measure at the time of abnormality, so that an operation error of the vehicle position detecting device due to a software abnormality or the like can be avoided, and in addition, rapid vehicle position control can be performed. Can be dealt with.

FIG. 3 is a block diagram showing the configuration of a modified example of the vehicle position detecting device according to the present invention. In FIG. 3, a predetermined magnetic sensor 16 detects the intensity of the magnetic flux from the magnetic generating means 12 embedded in the road 10, and the output is input to a magnetic determination circuit 22. The magnetic determination circuit 22 determines whether the magnetic flux intensity detected by the magnetic sensor 16 is equal to or greater than a predetermined value. In addition, wheel pulses indicating the number of rotations of the wheels are input to the distance counter 24, and the traveling distance of the vehicle 14 is integrated.

The magnetic determination circuit 22 outputs a reset signal of the distance counter 24 when it determines that the intensity of the magnetic flux detected by the magnetic sensor 16 is equal to or greater than a predetermined value. The running distance of the vehicle 14 integrated by the distance counter 24 is reset by the reset signal.

With this configuration, for example, when the output of the inner magnetic sensor shown in FIGS. 1 and 2 is taken as the magnetic sensor 16, as long as the position of the vehicle 14 is within the control range, the magnetic sensor 16 A detection output of a predetermined magnetic flux intensity is input to the magnetic determination circuit 22, whereby the traveling distance of the distance counter 24 is always reset.
On the other hand, when the position of the vehicle 14 is out of the control range in the lateral direction of the vehicle, the detection output of the magnetic sensor 16 is reduced, and the reset signal is not output from the magnetic determination circuit 22. Thereby, the vehicle 14 in the distance counter 24 is
The accumulated value of the mileage of the vehicle increases. A comparator 26 determines whether the integrated output of the distance counter 24 has exceeded a reference value m. In the comparator 26, the vehicle 1
If the travel distance of No. 4 is larger than the predetermined reference value m, it means that the vehicle has run out of the control range and has traveled the predetermined distance, and an abnormal output is output from the vehicle position detection device.

FIG. 4 is an operation explanatory diagram of a modified example of the vehicle position detecting device according to the present invention shown in FIG. FIG.
As shown in (2), the traveling distance of the vehicle 14 integrated by the distance counter 24 is reset at a predetermined cycle by a reset signal from the magnetic determination circuit 22. Therefore, while the magnetic flux detection output from the magnetic sensor 16 is equal to or greater than a predetermined value, that is, while the vehicle 14 is within the control range, the integrated value of the traveling distance of the vehicle 14 by the distance counter 24 is the reference value m.
Never exceed. On the other hand, when the position of the vehicle 14 is out of the control range, the detection output of the magnetic sensor 16 decreases, and the reset signal from the magnetic determination circuit 22 is not output. Will exceed the reference value m. At this point, an abnormal output is output from the vehicle position detecting device.

[0023]

As described above, according to the present invention,
When the vehicle position deviates beyond the control range in the width direction of the road (lateral direction of the vehicle), an abnormality in vehicle control can be detected with high accuracy.

If the above-described abnormality determination is performed not on the software but on the electric circuit, it is possible to avoid a problem due to the abnormality of the software and the like, and to secure high reliability.

Further, since an abnormal output from the vehicle position detecting device directly serves as a trigger signal for a measure in the event of an abnormality, an operation error of the vehicle position detecting device due to a software abnormality or the like can be avoided and, in addition, a quick response to abnormalities can be prevented. Response is possible.

[Brief description of the drawings]

FIG. 1 is a block diagram of a configuration of an embodiment of a vehicle position detection device according to the present invention.

FIG. 2 is an operation explanatory diagram of the vehicle position detecting device shown in FIG.

FIG. 3 is a block diagram showing a configuration of a modified example of the vehicle position detecting device according to the present invention.

FIG. 4 is an operation explanatory diagram of the vehicle position detecting device shown in FIG. 3;

FIG. 5 is an explanatory diagram of a configuration of a conventional vehicle position detecting device.

[Explanation of symbols]

10 road, 12 magnetism generating means, 14 vehicle, 16
Magnetic sensor, 18 level comparator, 20 difference calculator,
22 magnetic judgment circuit, 24 distance counter, 26 comparator.

Claims (3)

[Claims] A plurality of magnetic sensors are provided in a width direction of a vehicle for which lane keeping control is performed, and an output level of two predetermined magnetic sensors is equal to or more than a predetermined value, and the width of the vehicle among the two magnetic sensors is determined. A vehicle position detection device that determines that the vehicle control is abnormal when the output level of a magnetic sensor outside in the direction becomes larger than the output level of a magnetic sensor inside in the width direction of the vehicle. 2. The vehicle position detecting device according to claim 1, wherein the abnormality determination is performed by calculating a difference between output levels of the two magnetic sensors on an electric circuit. apparatus. 3. The vehicle position detection device according to claim 2, wherein the output of the electric circuit is used as it is as a trigger signal for a treatment when an abnormality occurs.