JP3707308B2 - Vehicle position detection device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle position detection device that recognizes a vehicle position by detecting a distance to a predetermined fixed point.
[0002]
[Prior art]
In conventional vehicle position detection, for example, a distance sensor or a camera is used, and the vehicle position is detected from distance detection information by the distance sensor or image information of the camera. For example, when detecting the vehicle position in a parking space surrounded by a wall and a white line, 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 are drawn on the ground. The vehicle position is recognized from the distance information and the position of the white line shown in the image.
[0003]
[Problems to be solved by the invention]
However, in the conventional apparatus as described above, for example, when the vehicle approaches the wall obliquely, the distance sensor detects a long distance position even though the distance to the wall is short. In addition, there is a problem that an error occurs in position recognition.
In order to solve such a problem, for example, a number of distance sensors must be mounted in a line 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]
In addition, since illumination is necessary for imaging by the camera, there is a problem that it cannot be used in a place where there is no illumination such as at night.
An object of the present invention is to provide a vehicle position detection device that is simple in configuration, low in cost, and capable of detecting a vehicle position over a wide range in view of the above-described conventional problems.
[0005]
[Means for Solving the Problems]
For this reason, the invention according to claim 1 is characterized in that transmission / reception means respectively installed at two predetermined positions on the vehicle, four return means installed at four fixed points in the parking space of the vehicle, and each of the transmission / reception means. Control means connected to the communication means, and each of the transmission / reception means communicates with two different reply means to detect the distance between them, and the control means detects the distance detected by each of the transmission / reception means. The vehicle position detecting device is characterized in that the vehicle position is calculated based on the above.
[0006]
Each transmission / reception means transmits a transmission signal with an identification code for identifying the transmission means, and each reply means recognizes the transmission signal from the transmission / reception means corresponding to the identification code and transmits a reply signal to perform communication. It can be carried out.
[0007]
According to a third aspect of the present invention, the 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 positional deviation, and detects the positional deviation. The movement information of the vehicle is created so as to be eliminated, and is output to the control system of the vehicle.
[0008]
【effect】
A plane coordinate system is constituted by four fixed points. If the distance between the two predetermined positions on the object whose direction is known and the four fixed points are obtained, the position of the object in the plane coordinate system is determined. All positions on the object are in a positional relationship with a predetermined position, and the position in the plane coordinate system can be obtained by coordinate transformation.
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 transmission / reception means and the four return means installed at the fixed points. The vehicle position is detected as described above. Furthermore, other positions on the vehicle can also determine the distance from the fixed point by coordinate conversion based on the positional relationship between the two predetermined positions.
As a result, the vehicle position can be detected in a wide range with a simple configuration and low cost.
Moreover, since this vehicle position detection does not depend on illumination, it can be used in an environment without illumination such as nighttime.
[0009]
In the invention according to claim 3, the control means detects the deviation of the vehicle position with respect to the target position, creates the movement information of the vehicle so as to eliminate the deviation, and outputs it to the control system of the vehicle. If the vehicle is moved based on the above, the vehicle can move following the set locus. This makes it possible for example to park automatically.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described by way of examples.
FIG. 1 is a conceptual diagram showing the configuration of the embodiment.
A transmission / reception device 6j is installed on the right side of the front end A of the vehicle 5, and a transmission / reception device 6i is installed on the left side of the rear end B. The transmission / reception devices 6 i and 6 j are connected to the control unit 7. On the other hand, parking spaces are set in the parking lots at fixed points a, b, c, and d. The distance between the fixed points a and b and 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, and 8d are respectively installed in the fixed points a, b, c, and d in a semi-embedded manner. The transmission / reception device 6i communicates with the return devices 8c and 8d, and the transmission / reception device 6j communicates with the return devices 8a and 8b, respectively, to detect the distance.
[0011]
FIG. 2 shows details of the configuration of the transmission / reception devices 6i and 6j.
The transmission / reception device 6i includes a reception unit 9, a code identification unit 10, a delay time detection unit 11, a distance detection unit 12, a transmission unit 14, a selection unit 15, a first identification code generation unit 17, and a second identification code generation unit 18. Composed.
The first identification code generator 17 generates an identification code 1 signal, and the second identification code generator 18 generates an identification code 2 signal. The selection unit 15 selects the identification code and outputs it to the transmission unit 14. The transmitter 14 adds the identification code signal to the transmission signal and transmits it.
[0012]
The receiving unit 9 receives a reply signal from the reply device. In the received signal, the identification code 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. When 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 detector 12 detects the distance from the reply device that has sent the reply signal from the time delay. The detected value is output to the control unit 7.
[0013]
The transmission / reception device 6j has the same configuration as that of the transmission / reception device 6i, and transmits a transmission signal to which an identification code is added and detects the distance from the response device by receiving a return signal. In the transmission / reception device 6j, the identification codes are the identification code 3 and the identification code 4 so that they can be distinguished from the transmission / reception device 6i.
[0014]
As shown in FIG. 3, the transmission / reception device 6 (6i, 6j) alternately transmits a signal and b signal having different identification codes at time intervals T. 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, respectively. The processing start time is performed after a time t2 after transmission of the transmission signal. The time t2 is set so that the distance detection process starts after the return signal is reliably received corresponding to the assumed detection distance.
[0015]
FIG. 4 is a diagram showing the configuration of the reply device 8 (8a, 8b, 8c, 8d). A transmission signal from the transmission / reception device 6 is received by the reception unit 19, and an 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.
[0016]
The identification code that can be identified by the reply device 8 varies depending on the fixed points installed. That is, the reply devices 8a, 8b, 8c, and 8d installed at the fixed points a, b, c, and d identify the identification code 1, the identification code 2, the identification code “3”, and the identification code 4, respectively. .
Thereby, the transmission / reception device 6i communicates with the reply devices c and d, respectively, and detects the distances ΔL3 and ΔL4 therebetween. The transmission / reception device 6j communicates with the return devices a and b, respectively, and detects the distances ΔL1 and ΔL2 therebetween.
[0017]
As described above, since the four distances are obtained from the two predetermined positions on the vehicle with respect to the four fixed points where the parking space is set, the vehicle position is detected. That is, as shown in FIG. 5, for example, if a circle of distances ΔL1 and ΔL2 obtained from each of the fixed points a and b is drawn, the position of the transmitting / receiving device 6j at which the intersection of the two communicates with the fixed points a and b It becomes.
[0018]
Since the vehicle 5 has the length H and the width Z known in advance as shown in FIG. 6, all the positions on the vehicle can be obtained on the vehicle coordinates with the position of the transmission / reception device 6i as the origin, for example.
When the vehicle 5 is parked in the parking space, it is determined whether or not the vehicle has reached a predetermined position based on the position of the vehicle coordinate system and the plane coordinate system composed of the fixed points b, c, and d as shown in FIG. can do. If it has not reached, the displacement can be calculated.
[0019]
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 a predetermined position is detected by detecting the vehicle position in the plane coordinate system constituted by the fixed points b, c, and c. The detected position is compared with the stored set position to detect a position shift. Based on the position shift, movement information for the vehicle to reach 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 coordinate conversion. Therefore, it is possible to manage the trajectory followed by each position on the outer periphery of the vehicle. If the vehicle moves according to this movement information, the vehicle can reach the set position while following a predetermined trajectory.
[0020]
Next, the operation flow of the above configuration will be described with reference to the flowchart of FIG.
First, the control part 7 operates the transmission / reception apparatus 6j. Accordingly, in step 110, the transmission / reception device 6j transmits a transmission signal to which the identification code 1 is 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 reply signal and the transmission signal.
[0021]
In step 112 and step 113, the transmission / reception device 6j transmits a transmission signal of the identification code 2, and calculates the distance from the fixed point b.
When transmission / reception of the transmission / reception device 6j is completed, the control unit 7 operates the transmission / reception device 6i. The transmitter / receiver 6i calculates and detects the distance between the fixed points c and d in steps 114 to 117 in the same manner as described above.
In step 118, the control unit 7 recognizes the vehicle position with respect to the fixed point from the four detected distances.
In step 119, the control unit 7 detects a deviation between the vehicle position and the set position.
[0022]
In step 120, the control unit 7 determines whether or not there is a deviation. If there is a deviation, in step 121, based on the deviation amount, movement information relating to the direction and distance to which the vehicle should move is created in step 121, output to the vehicle control system, and the process returns to step 110. As a result, the vehicle can move according to the movement information. On the other hand, if there is no deviation, the loop is terminated assuming that the vehicle has reached the set position.
[0023]
This embodiment is configured as described above, and the vehicle position is detected based on distance information obtained by transmission / reception between two transmission / reception devices installed on the vehicle and four return devices installed at fixed points. Therefore, the position can be detected within a range where transmission and reception are possible, and the vehicle position can be detected over a wide range.
In addition, if the detected vehicle position deviates from the set position, the deviation can be detected, and the direction and distance of movement of the vehicle so as to eliminate the deviation can be obtained, so that the vehicle can be parked automatically. 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 illustrating 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]
5 Vehicle 6i, 6j Transmission / reception device (transmission / reception means)
7 Control unit (control means)
8a, 8b, 8c, 8d Reply device (reply means)
9 receiving unit 10 transmitting unit 11 delay time detecting unit 12 distance detecting unit 14 transmitting unit 15 selecting unit 17 first identification code generating unit 18 second identification code generating unit a, b, c, d fixed point

Claims (3)

Transmission / reception means respectively installed at two predetermined positions on the vehicle;
Four reply means installed at four fixed points in the parking space of the vehicle;
Control means connected to each of the transmission / reception means,
Each of the transmission / reception means communicates with two different return means to detect a distance therebetween, and the control means calculates a vehicle position based on the distance detected by each of the transmission / reception means. A vehicle position detecting device. Each of the transmission / reception means transmits a transmission signal with an identification code identifying the transmission means, and each of the return means recognizes a transmission signal from the transmission / reception means corresponding to the identification code and transmits a reply signal. The vehicle position detection device according to claim 1, wherein The control means stores a target position of the vehicle, and the control means compares the detected vehicle position with the target position to detect a positional deviation and move the vehicle so as to eliminate the positional deviation. 3. The vehicle position detection apparatus according to claim 1, wherein information is generated and output to a control system of the vehicle.

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