JP2001051720A - Vehicle position detection device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To detect a vehicle position by performing transmission and reception. SOLUTION: Transmission / reception devices 6j and 6i are attached to a front end A and a rear end B of a vehicle, respectively. Return devices 8a, 8b, 8c, 8d are respectively installed at fixed points a, b, c, d at predetermined distances in the parking space. The transmission / reception device 6j communicates with the reply devices 8a and 8b to obtain the distance ΔL
1. Detect ΔL2. The transmitting / receiving device 6i is a reply device 8
The communication is performed with c and 8d to detect the distances ΔL3 and ΔL4. The control unit 7 recognizes the vehicle position from the detected distance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle position detecting device for detecting a distance to a predetermined fixed point to recognize a vehicle position.

[0002]

2. Description of the Related Art In conventional vehicle position detection, for example, a distance sensor or a camera is used to detect a vehicle position based on distance detection information from a distance sensor or image information from a camera. For example, when detecting vehicle position in a parking space surrounded by walls and white lines, a distance sensor attached to the front or rear end of the vehicle detects the distance to the wall, and cameras attached to both sides of the vehicle draw white lines drawn on the ground Is imaged, and the vehicle position is recognized from the distance information and the position of the white line projected on the image.

[0003]

However, in the above-mentioned conventional apparatus, for example, the vehicle is obliquely moved.
When approaching a wall, there is a problem that an error occurs in position recognition when the distance sensor detects a long distance position, even though the distance to the wall is short. In order to solve such a problem, for example, a large number of distance sensors must be mounted in a row at the front end or the rear end of the vehicle, and there is a problem that the configuration is complicated and the cost increases.

[0004] Further, since illumination is required for imaging by a camera, there is a problem that it cannot be used in a place without illumination such as at night. SUMMARY OF THE INVENTION The present invention has been made in consideration of the above-described conventional problems, and has as its object to provide a vehicle position detection device that has a simple configuration, can detect a vehicle position over a wide range at low cost.

[0005]

According to a first aspect of the present invention, there is provided a transmission / reception means installed at two predetermined positions on a vehicle, and at least three transmission / reception means in a parking space of the vehicle.
And four control means connected to each of the transmitting and receiving means, wherein each of the transmitting and receiving means communicates with two different ones of the reply means to reduce a distance therebetween. The vehicle position detecting device detects the vehicle position based on the distance detected by each of the transmitting and receiving units.

[0006] Each of the transmitting / receiving means adds an identification code for identifying the transmitting means to the transmission signal and transmits the signal. Each replying means recognizes the transmission signal from the corresponding transmitting / receiving means based on the identification code and transmits a reply signal. , Can communicate.

According to a third aspect of the present invention, a target position of the vehicle is stored in the control means, and the control means compares the detected vehicle position with the target position to detect a position shift. The movement information of the vehicle is created so as to eliminate the displacement, and is output to the control system of the vehicle.

[0008]

[Effect] A plane coordinate system is constituted by three fixed points. If the distance between two predetermined positions on the object whose orientation is known and the three fixed points is determined, the position of the object in the plane coordinate system is determined. Based on the positional relationship between all positions on the object and the predetermined position, the position in the plane coordinate system can be obtained by coordinate conversion. According to the first aspect of the present invention, the distance from two predetermined positions on the vehicle to two different fixed points in the parking space can be obtained by the two transmitting / receiving means and the four reply means provided at the fixed points. Then, the vehicle position is detected as described above. Further, the distance to the fixed point can be obtained by coordinate conversion at other positions on the vehicle, based on the positional relationship with the two predetermined positions. As a result, the vehicle position can be detected over a wide range with a simple configuration, at low cost, and with low cost. Also,
Since this vehicle position detection does not depend on lighting, it can be used in an environment without lighting such as at night.

According to the third aspect of the present invention, the control means detects a deviation of the vehicle position from the target position, creates movement information of the vehicle so as to eliminate the deviation, and outputs the information to the control system of the vehicle. If you move the vehicle based on that information,
The vehicle can move following the set trajectory.
This makes it possible, for example, to park automatically.

[0010]

Next, embodiments of the present invention will be described with reference to examples. FIG. 1 is a conceptual diagram showing the configuration of the embodiment. A transmitting / receiving device 6j is installed on the right side of the front end A of the vehicle 5, and a transmitting / receiving device 6i is installed on the left side of the rear end B. The transmission / reception devices 6i and 6j are connected to the control unit 7. On the other hand, a parking space is set in the parking lot at fixed points a, b, c, and d. The distance between the fixed points a and b, d and c is W, and the distance between the fixed points a and d and b and c is L. Reply devices 8a, 8b, 8c, 8d are respectively installed at the fixed points a, b, c, d in a semi-embedded manner. The transmission / reception device 6i is a reply device 8c, 8
d, The transmission / reception device 6j communicates with the reply devices 8a and 8b, respectively, to detect the distance.

FIG. 2 shows the details of the configuration of the transmission / reception devices 6i and 6j. The transmitting / receiving device 6i includes a receiving unit 9, a code identifying unit 1,
0, delay time detecting section 11, distance detecting section 12, transmitting section 1
4, the selection unit 15, the first identification code generation unit 17, the second
It comprises an identification code generation unit 18. The first identification code generation section 17 generates an identification code 1 signal, and the second identification code generation section 18 generates an identification code 2 signal. Selector 15
Selects an identification code and outputs it to the transmission unit 14. The transmitting unit 14 adds the identification code signal to the transmission signal and transmits the signal.

The receiving section 9 receives a reply signal from the reply device. The identification code of the received signal is detected by the code identification unit 10, and it is determined whether or not the identification code matches the identification code at the time of transmission. If they match, the delay time detection unit 11 operates to detect a time delay of the reception time with respect to the transmission time. The distance detecting unit 12 detects the distance from the reply device that has transmitted the reply signal from the time delay. If the detected value is
Is output to

The transmitting / receiving device 6j has a configuration similar to that of the transmitting / receiving device 6i. The transmitting / receiving device 6j transmits a transmission signal to which an identification code is added, and detects a distance from the response device by receiving a return signal. In the transmitting / receiving device 6j, the identification codes are the identification code 3 and the identification code 4, respectively, so as to be distinguishable from the transmitting / receiving device 6i.

The transmitting / receiving device 6 (6i, 6j) alternately transmits the signals a and b having different identification codes at time intervals T as shown in FIG. The duration of the transmission signal is t1, and the time delays Δt1 and Δt2 until the return signal is received and the processing time Δt for detecting the distance are set within the time interval T. The processing is started after the transmission signal transmission time t2 has elapsed. The time t2 is set so that the distance detection process is started after the return signal is reliably received corresponding to the assumed detection distance.

FIG. 4 shows a reply device 8 (8a, 8b, 8c, 8).
It is a figure which shows the structure of d). The transmission signal from the transmission / reception device 6 is received by the reception unit 19, and the identification code is identified by the code identification unit 20. The return signal creation unit 21 creates a return signal so as to return the received signal, and the transmission unit 22 sends the return signal.

The identification code that can be identified by the reply device 8 differs depending on the fixed point installed. That is, the fixed point a,
Reply devices 8a, 8b, 8c, 8 installed at b, c, d
d identifies the identification code 1, the identification code 2, the identification code # 3, and the identification code 4, respectively. As a result, the transmitting / receiving device 6i respectively returns the reply devices c and d.
And the distances ΔL3 and ΔL4 between them are detected. The transmission / reception device 6j communicates with the reply devices a and b, respectively, and detects the distances ΔL1 and ΔL2 therebetween.

As described above, the parking space 4 is set.
Since four distances are obtained from two predetermined positions on the vehicle for one fixed point, the vehicle position is detected. That is, as shown in FIG. 5, for example, if circles of the distances ΔL1 and ΔL2 obtained from the fixed points a and b are drawn, the intersection of the two points is the position of the transmitting / receiving device 6j that has communicated with the fixed points a and b. Becomes

Since the length H and the width Z of the vehicle 5 are known in advance as shown in FIG. 6, all positions on the vehicle can be determined on vehicle coordinates with the origin of the position of the transmitting / receiving device 6i, for example. . When the vehicle 5 is parked in the parking space,
As shown in FIG. 7, whether or not the vehicle has reached a predetermined position can be determined based on the position of the vehicle coordinate system and the position of the plane coordinate system constituted by, for example, fixed points b, c, and d. If it has not arrived, the displacement can be calculated.

The control unit 7 recognizes the vehicle position based on the distance information from the transmission / reception devices 6i and 6j. Whether or not the vehicle 5 has reached the predetermined position is detected by detecting the vehicle position in the plane coordinate system formed by the fixed points b, c, and c. The detected position is compared with the stored set position to detect a position shift, and based on the position shift, movement information for the vehicle to come to the set position is created and output to the control system of the vehicle 5. Since the positions of the vehicle coordinate system and the plane coordinate system are determined, an arbitrary position on the vehicle can be detected by the coordinate conversion. Therefore, it is possible to manage the trajectory of each position on the outer periphery of the vehicle.
If the vehicle moves according to the movement information, the vehicle can reach the set position while following a predetermined locus.

Next, the operation flow of the above configuration will be described with reference to the flowchart of FIG. First, the control unit 7
Activates the transmitting / receiving device 6j. Accordingly, in step 110, the transmitting / receiving device 6j transmits a transmission signal to which the identification code 1 has been added, and the transmission signal is received by each return device. Since the reply device 8a installed at the fixed point a can identify the identification code 1, it sends a reply signal. In step 111, the transmission / reception device 6j calculates the distance to the fixed point a from the time delay between the return signal and the transmission signal.

In steps 112 and 113, the transmission / reception device 6j transmits the transmission signal of the identification code 2, and calculates the distance to the fixed point b. When the transmission / reception of the transmission / reception device 6j is completed, the control unit 7 operates the transmission / reception device 6i. The transmitting / receiving device 6i performs Step 11 in the same manner as described above.
In steps 4 to 117, the distance between the fixed points c and d is calculated and detected. In step 118, the control unit 7 recognizes the vehicle position with respect to the fixed point from the detected four distances. In step 119, the control unit 7 detects a deviation between the vehicle position and the set position.

In step 120, the control section 7 determines whether or not there is a deviation. If there is a deviation, in step 121, movement information relating to the direction and distance to which the vehicle should move is created in step 121 based on the deviation amount, output to the control system of the vehicle, and the process returns to step 110. Thus, the vehicle can move according to the movement information. On the other hand, if there is no deviation, it is determined that the vehicle has reached the set position, and the loop is ended.

This embodiment is configured as described above. The vehicle position is detected by two transmitting / receiving devices installed on the vehicle,
Since it is obtained based on the distance information obtained by transmission and reception with the four reply devices installed at the fixed points, the position can be detected and the vehicle position can be detected in a wide range as long as transmission and reception are possible. In addition, if the detected vehicle position is shifted from the set position, the shift can be detected, and the direction and distance in which the vehicle moves so as to eliminate the shift can be obtained, so that the vehicle can be automatically parked. Become.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a configuration of an embodiment.

FIG. 2 is a diagram illustrating details of a configuration of a transmission / reception device.

FIG. 3 is a time chart of transmission / reception and processing.

FIG. 4 is a diagram showing a configuration of a reply device.

FIG. 5 is an explanatory diagram of position recognition.

FIG. 6 is an explanatory diagram of a vehicle coordinate system.

FIG. 7 is a diagram showing a vehicle position in a plane coordinate system.

FIG. 8 is a flowchart for creating movement amount information.

[Explanation of symbols]

 Reference Signs List 5 vehicle 6i, 6j transmission / reception device (transmission / reception means) 7 control unit (control means) 8a, 8b, 8c, 8d reply device (reply means) 9 reception unit 10 transmission unit 11 delay time detection unit 12 distance detection unit 14 transmission unit 15 Selector 17 First identification code generator 18 Second identification code generator a, b, c, d Fixed points

Claims (3)

[Claims] 1. A transmission / reception unit installed at two predetermined positions on a vehicle, four return units installed at at least three fixed points in a parking space of the vehicle, and connected to the transmission / reception units. Control means, wherein each of the transmitting and receiving means communicates with two different reply means, respectively, to detect a distance therebetween, and the control means determines a vehicle position based on the distance detected by each of the transmitting and receiving means. A vehicle position detecting device for calculating the position. 2. Each of the transmitting and receiving means transmits a transmission signal with an identification code for identifying the transmission means added thereto, and each of the reply means recognizes a transmission signal from the corresponding transmission and reception means from the identification code and returns a response signal. The vehicle position detecting device according to claim 1, wherein 3. The control means stores a target position of the vehicle, and the control means compares the detected vehicle position with the target position, detects a position shift, and eliminates the position shift. The vehicle position detecting device according to claim 1 or 2, wherein the vehicle movement information is generated and output to a control system of the vehicle.