JPH02193014A - Magnetization corrector for body - Google Patents

Abstract

PURPOSE:To enable automatic correction of a magnetized component of a body by determining the current position of a vehicle based on an ongoing direction of the vehicle detected with an earth magnetism sensor and a running distance detected with a distance sensor. CONSTITUTION:As a vehicle advances, an earth magnetism sensor 2 carried on the vehicle checks an earth magnetism to detect an ongoing direction of a vehicle. When a distance sensor 3 detects a running distance of the vehicle, a position locator 4 updates a current position data of the vehicle by an autonomous navigation method. Then, when a body is magnetized, a detection error of the sensor 2 is generated and an error is generated in the current position data of the vehicle. Moreover, the vehicle advances and comes near a transmitter and when a position signal receiver 1 carried on the vehicle receives a position signal from the transmitter, the device 4 corrects the current position data of the vehicle by the position signal thereby enabling automatic correction of a magnetization signal of the body.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a vehicle body magnetization correction device used in a navigation system using a geomagnetism detection sensor, a car locator system, and the like.

Conventional Technology In general, navigation systems and car locator systems that detect their own position using self-contained navigation include a geomagnetism detection sensor that detects the direction of travel of a vehicle by detecting the geomagnetism, and a distance sensor that detects the distance traveled by the vehicle. It is equipped with sensors, etc., and is configured to evaluate the current position of the vehicle based on the traveling direction and travel distance.

However, when the direction of movement of a vehicle or the like is detected by this geomagnetism detection sensor, a detection error occurs if the vehicle body is magnetized, so the magnetization component of the vehicle body must be corrected.

FIG. 3 is an explanatory diagram showing a conventional method for correcting the magnetization component of the vehicle body. Let the magnetization component of the vehicle body be the magnetization vector 00' and the actual geomagnetic component be the geomagnetic vector OH. , the component detected by the geomagnetism detection sensor becomes the sensor detection vector OP.

This correction method utilizes the fact that the magnetized component of the car body is fixed relative to the car body, and that when the car body rotates in a horizontal plane, the actual geomagnetic component draws a circular trajectory centered on point 0. .

Therefore, in order to know the magnitude and direction of the magnetized component of the vehicle body, it is necessary to find the center point 0 of the circular trajectory, and the user must periodically or By rotating the vehicle body each time and measuring the center point O of the circular locus, the magnetization component of the vehicle body can be corrected.

Problems to be Solved by the Invention However, in the conventional car body magnetization correction method described above, the user has to rotate the car body periodically or each time while being aware of the magnetization of the car body, so the operation is troublesome. There is a problem.

SUMMARY OF THE INVENTION In view of the above conventional problems, it is an object of the present invention to provide a vehicle body magnetization correction device that can automatically correct the magnetization component of a vehicle body.

Means for Solving the Problems In order to achieve the above object, the present invention arranges a transmitter that wirelessly transmits an absolute position along a road, etc., and a geomagnetic sensor detects the transmitter installed in the vehicle. The current position of the vehicle is evaluated based on the traveling direction of the vehicle and the travel distance detected by the distance sensor, and when the absolute position is received from the transmitter, the current position of the vehicle is evaluated based on the evaluated current position and the absolute position. The error in the traveling direction due to magnetization is calculated, and the current position is corrected based on this error.

According to the above-described configuration, the present invention calculates the error in the traveling direction due to the magnetization of the vehicle body every time the on-vehicle device receives the absolute position from the transmitter, so that the magnetization component of the vehicle body can be automatically corrected. can.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic block diagram showing an embodiment of the vehicle-mounted device of the vehicle body magnetization correction device according to the present invention, and FIG. 2 shows an embodiment of the transmitter of the vehicle body magnetization correction device according to the present invention. FIG. 2 is a schematic block diagram.

In FIG. 1, 1 is a position signal receiver that receives a position signal from a transmitter as shown in FIG. , a distance sensor that detects the distance traveled by the vehicle, 4
As will be described later, based on the position signal received by the position signal receiver 1, the traveling direction detected by the geomagnetic sensor 2, and the traveling distance detected by the distance sensor 3,
This is a position evaluation device that evaluates the current position of a vehicle.

In FIG. 2, a plurality of transmitters are installed along a road, etc., and include a coordinate storage device 5 that stores in advance the coordinates (absolute position) of the installed narrow area, and a coordinate storage device 5 that stores coordinate position data from the coordinate storage device 5. The general configuration includes a signal transmitter 6 that modulates a wireless carrier wave, and an antenna 7 that radiates the carrier wave modulated by the signal transmitter 6 toward the road surface.

Next, the operation of the above embodiment will be explained.

In FIG. 1, as the vehicle advances, the geomagnetic sensor 2 of the on-vehicle device detects the geomagnetism to detect the traveling direction of the vehicle, and when the distance sensor 3 detects the traveling distance of the vehicle, the position evaluation device 4 updates the vehicle's current position data using autonomous navigation. Here, if the vehicle body is magnetized, a detection error of the geomagnetic sensor 2 occurs, so an error occurs in the current position data of the vehicle.

When the vehicle advances and reaches the vicinity of the transmitter, and the position signal receiver 1 of the onboard device receives the position signal from the transmitter, the position evaluation device 4 corrects the current position data of the vehicle using this position signal. .

Next, until the position signal is received from the next transmitter, the error that occurs each time the vehicle's current position data is updated using self-contained navigation is integrated using the amount of magnetization m of the vehicle body as a variable. The calculated error value E (m)
seek.

When the position signal from the next transmitter is received, the difference between the position signal and the current position data evaluated by self-contained navigation, that is, the absolute value ε of the error that frequently occurs during self-contained navigation is determined.

Here, since the calculated value E (m) and the absolute value ε are equal, the amount of magnetization m of the vehicle body, which was a variable, can be obtained, and this amount of magnetization m is used as a correction value for the vehicle body magnetization to evaluate the position. Update the constants of device 4.

Therefore, according to the above embodiment, each time the position evaluation device 4 receives the absolute position from the transmitter placed along the road, the position evaluation device 4 updates the correction value of the vehicle body magnetization. The correction can be made automatically, and therefore there is no need for the user to rotate the vehicle body periodically or each time with awareness of the magnetization of the vehicle body, as in the conventional example.

As described in detail, the present invention has a transmitter that wirelessly transmits an absolute position placed along a road, etc., and an in-vehicle device mounted inside the vehicle that detects the progress of the vehicle detected by a geomagnetic sensor. The current position of the vehicle is evaluated based on the direction and distance detected by the distance sensor, and when the absolute position is received from the transmitter, the traveling direction is determined by magnetizing the vehicle body based on the evaluated current position and the absolute position. Since the error is calculated and the current position is corrected using this error, the magnetization component of the vehicle body can be automatically corrected.

[Brief explanation of the drawing]

FIG. 1 is a schematic block diagram showing an embodiment of the vehicle-mounted device of the vehicle body magnetization correction device according to the present invention, and FIG. 2 shows an embodiment of the transmitter of the vehicle body magnetization correction device according to the present invention. The schematic block diagram in FIG. 3 is an explanatory diagram showing a conventional method for correcting the magnetization component of a vehicle body. 1...Position signal receiver, 2...Geomagnetic sensor, 3.
... Distance sensor, 4... Position evaluation device, 5... Coordinate storage device, 6... Signal transmitter, 7... Antenna.

Claims (1)

[Claims] A transmitter placed along the road etc. transmits its absolute position wirelessly, and a transmitter mounted inside the vehicle detects the vehicle's traveling direction detected by a geomagnetic sensor and the distance traveled detected by a distance sensor. In addition to evaluating the current location,
An on-vehicle unit comprising: an on-vehicle device that calculates an error in the traveling direction due to magnetization of the vehicle body based on the evaluated current position and the absolute position when the absolute position is received from the transmitter, and corrects the current position based on this error. Magnetic correction device.