JP2000356526A - Measuring system for running route of moving body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring system for the running route of a moving body, in which the accuracy of a positioning operation is enhanced and whose cooperation with other measuring devices is easy. SOLUTION: A GPS positioning means 2 which finds the situated latitude and the situated longitude of a moving body by receiving satellite radio waves and which outputs positioning information in which the positioning time at the reception of the satellite radio waves and the present time are added to the latitude and the longitude is provided. A positioning- information storage means 6 which stores the positioning information is provided. A sensors 3 and 4 which detect the angle and the movement distance of the moving body are provided. An autonomous positioning means 5 which finds a position change within a described time on the basis of information detected by the sensors is provided. Then, when the reception state of the satellite radio waves in the GPS positioning means 2 becomes bad, a latitude and a longitude are found in such a way that a position change due to an autonomous positioning operation at a time agreeing with the positioning time is added to the latitude and the longitude, by a GPS positioning operation, stored in the positioning-information storage means 6 by adding a positioning time immediately before the reception state becomes bad. The latitude and the longitude by the autonomous positioning operation are stored in the positioning-information storage means 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for measuring a traveling route of a mobile body using both GPS positioning and autonomous positioning, and more particularly to a mobile body having improved positioning accuracy and easy cooperation with other measuring devices. The present invention relates to a travel route measurement system.

[0002]

2. Description of the Related Art The position of a moving object (for example, represented by latitude and longitude)
As a positioning method (or navigation) for measuring GPS, a global positioning system (GPS) using artificial satellites is used.
A combination of GPS positioning using em) and autonomous positioning performed by detecting the angle and moving distance of a moving object by a sensor is known. For example, the conventional moving object position detecting device can obtain the latitude and longitude using the position change obtained by autonomous positioning while the latitude and longitude cannot be obtained by GPS positioning.

[0003] In the conventional mobile object position detecting device, when satellite radio wave reception by the GPS positioning means is interrupted, autonomous positioning is switched to the autonomous positioning from the interrupted time point to obtain latitude and longitude, and the current time is added to the latitude and longitude. Creating information.

[0004] By storing the positioning information output by the mobile object position detecting device for each time, the route traveled by the mobile object can be measured.

[0005]

The prior art has the following problems.

[0006] (1) The latitude and longitude by GPS positioning are obtained later than the time when the latitude and longitude were actually measured (the time when the GPS positioning means received the satellite radio wave). This is because it takes time to obtain the latitude and longitude from the radio wave reception information and to output the obtained latitude and longitude by serial transmission. On the other hand, in autonomous positioning, latitude and longitude are obtained from a position change at the current time. Therefore, the time synchronization between the latitude and longitude based on the GPS positioning and the position change based on the autonomous positioning is shifted. If a position change due to autonomous positioning is used for interpolation of latitude and longitude by GPS positioning without time synchronization, an error corresponding to the movement of the moving body during the synchronization deviation time occurs.

(2) The latitude and longitude information output from the moving object position detecting device does not include the output time and the positioning time. For this reason, the correlation between the measurement information output by measuring devices other than the moving object position detecting device, for example, the measured values such as the radio wave intensity of the communication device and the condition of the road surface, and the latitude and longitude information output by the moving object position detecting device, Difficult to take. Therefore, it is difficult to make the moving object position detecting device cooperate with another measuring device.

(3) Since there is no means to add post-processing to information (position change, etc.) obtained by autonomous positioning and to correct the information,
The positioning accuracy cannot be improved.

An object of the present invention is to solve the above-mentioned problems, to provide a moving body traveling route measuring system which improves the positioning accuracy and can easily cooperate with other measuring instruments.

[0010]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention obtains a latitude and longitude where a mobile object is located by receiving a satellite radio wave, and determines the positioning time and time when the satellite radio wave was received at the latitude and longitude. GPS positioning means for outputting positioning information to which the current time is added, positioning information storage means for storing the positioning information, sensors for detecting the angle and the moving distance of the moving body, Autonomous positioning means for obtaining a change in the position of the GPS positioning means, when the reception state of the satellite radio wave in the GPS positioning means becomes poor,
The positioning information storage means is added with the positioning time immediately before the reception state becomes bad and stored, and the latitude and longitude are calculated by adding the position change by autonomous positioning at the time corresponding to the positioning time to the latitude and longitude by GPS positioning. The latitude and longitude obtained by the autonomous positioning are stored in the positioning information storage means.

[0011] Of the latitude and longitude stored in the positioning information storage means, the latitude and longitude by autonomous positioning are the latitude and longitude by GPS positioning before the reception state becomes poor and the latitude and longitude by GPS positioning after the reception state is successfully restored. The correction may be made with the longitude.

An azimuth difference and a distance difference are obtained from a latitude and longitude based on GPS positioning after the reception state has been restored satisfactorily and a latitude and longitude based on autonomous positioning immediately before the reception state has been restored satisfactorily. By averaging, the detection error of the sensor over the period in which the reception state was bad was obtained, and the reception was performed using the detection information of the sensor corrected by the detection error and the latitude and longitude by the GPS positioning before the reception state became bad. The latitude / longitude of the autonomous positioning during the period in which the state is bad may be obtained again, and the latitude / longitude may be stored again in the positioning information storage means.

The positioning information may be added with information for determining whether the latitude and longitude are based on GPS positioning or the latitude and longitude based on autonomous positioning, and stored in the positioning information storage means.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

The moving object traveling route measurement system shown in FIG. 1 is mounted on a vehicle 1, and includes a GPS receiver 2, a vehicle speed sensor 3, an optical gyro 4, and an autonomous navigation unit 5.
And a host computer 6. 7 is a battery, 8 is an antenna.

The GPS receiver 2 constitutes a GPS positioning means, and obtains the latitude and longitude of the receiving position by receiving satellite radio waves at fixed time intervals, and obtains the time when the satellite radio waves were received at the obtained latitude and longitude (hereinafter, referred to as the GPS receiver). , Positioning time) and the current time for output. The GPS receiving device 2 calculates the azimuth and speed of the movement trajectory of the GPS receiving device 2 from changes in latitude and longitude at the two most recent positioning times, and outputs the azimuth and speed together with the latitude and longitude and time. it can. Further, the GPS receiver 2 outputs reliability information indicating the reliability of the output latitude and longitude based on the reception state of satellite radio waves (for example, the number of captured satellites). Also, it outputs a synchronization pulse PPS synchronized with the positioning time.

The vehicle speed sensor 3 detects a wheel rotation pulse. The optical gyro 4 detects an angular velocity occurring in the vehicle 1 from a change in light passing through the optical fiber.

The autonomous navigation unit 5 constitutes an autonomous positioning means, and always calculates the traveling distance l _i of the vehicle at regular time intervals by counting the rotation pulses of the vehicle speed sensor 3, thereby obtaining the optical gyro 4. from the angular velocity calculating an angle theta _i of the vehicle at predetermined time intervals. The time interval is the same as the positioning time interval of the GPS receiver 2. The angle θ _i and the traveling distance l _i are stored in the autonomous navigation unit 5 as detection information of each sensor.

The autonomous navigation unit 5 includes the GPS receiver 2
Can be analyzed to determine whether the reception status of the satellite radio wave is good or bad.

The autonomous navigation unit 5 outputs the positioning information from the GPS receiver 2 to the host computer 6 without processing when the reception condition is good, but when the reception condition is bad, the reception condition is good. The autonomous positioning is performed using the detection information of each sensor that has been traced to the proper positioning time, and the positioning information is output to the host computer 6. Information for determining whether the positioning information is a latitude / longitude by GPS positioning or a latitude / longitude by autonomous positioning is added to the positioning information.

The host computer 6 is provided with positioning information storage means for storing positioning information received from the autonomous navigation unit 5.

The autonomous positioning in the present invention is performed as follows.

It is assumed that the azimuth determined by the GPS positioning at the positioning time immediately before the reception state becomes bad is α, and that n times of positioning time intervals have passed since the positioning time at which the reception state became poor. Assuming that the azimuth after passing the n positioning time intervals is φ _n ,

[0024]

(Equation 1)

## EQU1 ##

As shown in the above equation (1), the azimuth φ _n is obtained by summing the previous azimuth α and the angle change θ _i −θ _i−1 for each positioning time interval for n times.

If the relative positions (position changes) expressed in the XY orthogonal coordinate system when n positioning time intervals have passed from the positioning time immediately before the reception state becomes bad are X _n and Y _n , X _n, Y _n, as shown in equation (2), and n times of the sum of n times of the sum and Y components of the X component of the movement distance l _i for each positioning time interval. The X component and the Y component each time are obtained by a trigonometric function using the azimuth φ _i each time.

The relative positions X _n and Y _n are corrected for the GPS just before the reception state becomes poor by performing an elliptical spherical correction of the earth.
By adding to the latitude and longitude by the positioning, the latitude and longitude by the autonomous positioning after the positioning time when the reception state becomes poor can be obtained. The autonomous navigation unit 5 outputs positioning information obtained by adding the positioning time and the current time to the latitude and longitude.

The host computer 6 stores the positioning information received from the autonomous navigation unit 5 including the time, latitude and longitude, type of positioning method, and the like.

The correction of the autonomous positioning result in the present invention is performed as follows.

The positioning information stored in the host computer 6 is corrected and calculated by post-processing. The correction calculation is performed as follows.

The correction calculation targets latitude and longitude by autonomous positioning performed during a period in which the reception state is poor. The correction calculation is

[0033]

(Equation 2)

Is executed by using Here, the initial azimuth error Δα is obtained by linearly approximating the azimuth α by GPS positioning at the positioning time before the reception state becomes poor and the latitude and longitude by a plurality of times of GPS positioning before the reception state becomes poor. This is the difference from the true bearing indicated by the actual traveling locus. Since the azimuth α by GPS positioning is obtained from the two most recent positioning points, the azimuth α has an error Δα with respect to the true azimuth indicated by the actual traveling locus, and this error Δα affects subsequent autonomous positioning.
The angle drift Δθ of the optical gyro is the difference between the azimuth after return calculated from the latitude and longitude after the reception state has returned well and the final azimuth by autonomous positioning divided by the elapsed time during the autonomous positioning. It is. The distance error coefficient ε is Δα, Δ
The latitude and longitude corresponding to the relative positions X _n and Y _n are obtained by calculation using θ, and the distance difference between this latitude and longitude and the latitude and longitude after the reception state has been properly restored is divided by the travel distance. Δ
The latitude and longitude by the autonomous positioning are corrected by the calculation using α and Δθ, and the correction is completed by causing the host computer 6 to re-store the latitude and longitude.

The moving object traveling route measuring system of the present invention can easily cooperate with other measuring devices. The latitude / longitude stored in the host computer 6 is a latitude / longitude obtained by GPS positioning or a latitude / longitude corrected by post-processing.
This represents the position of the moving object at the PS positioning time. If the measurement data of the measurement device mounted on the moving object is stored together with the measurement time, the position where the data was measured from the latitude and longitude measured at the measurement time can be accurately specified. Further, for the time synchronization, if the synchronization pulse PPS output from the GPS receiver 2 every second is used, precise synchronization is possible.

Since the distance error coefficient ε of the vehicle speed sensor 3 changes depending on the tire pressure and the road surface condition, it is desirable to always calibrate with the GPS speed data.

In the above embodiment, the moving body traveling route measuring system mounted on the vehicle 1 has been described. In this case, the distance information may be obtained from a pedometer.

In the above embodiment, the angle drift Δθ of the optical gyro is corrected, but a scale error (rotation error) may be corrected. Further, by adding a tilt angle sensor and correcting the rotation angle and the distance based on the tilt angle detected by the tilt angle sensor, higher accuracy can be achieved.

The application of the present invention includes the following physical quantity distribution measurement.

(1) Detection of Gas Leakage Location In order to detect gas leaks such as public gas, a service vehicle equipped with a gas analyzer is patrolled, and gas detection is performed at each point on the patrol route. When displaying a detection point on an electronic map, when satellite radio wave reception by the GPS positioning means is interrupted as in the prior art, switching to autonomous positioning from the interrupted point and simply obtaining latitude and longitude simply requires the positioning time of both. Does not match. In addition, the measurement time of the gas analyzer does not always match the positioning time of latitude and longitude. Further, the position information obtained by autonomous positioning is inferior in accuracy to that obtained by GPS positioning. On the other hand, in the present invention, the GPS positioning, the autonomous positioning, and the measurement time of the measuring device all coincide. Also, the position information obtained by the autonomous positioning is corrected after the GPS reception is restored, so that the position accuracy is good. Therefore, it is possible to accurately detect a gas leak location.

(2) Measurement of electric field strength distribution in a mobile communication system such as a mobile phone The electric field strength distribution brought by the base station of the mobile communication into the service area is cyclically measured by an on-vehicle electric field strength meter. Also in this case, the measurement position can be displayed on the electronic map with high accuracy according to the present invention, similarly to the case of detecting the gas leaking place.

(3) Detection of Road Surface Irregularities On a road, a vehicle is equipped with a measuring device for measuring road surface irregularities, the vehicle is driven on a road, and marked irregularities are displayed on an electronic map. Also in this case, the measurement position can be displayed with high accuracy according to the present invention, as in the case of detecting the gas leaking place.

(4) Measurement of Distribution of Environmental Values Environmental values such as the concentration of harmful gas in the atmosphere, noise, and radiation are measured by an onboard measuring instrument. Also in this case, the measurement position can be displayed with high accuracy according to the present invention, as in the case of detecting the gas leaking place.

[0044]

The present invention exhibits the following excellent effects.

(1) Since the positioning time based on the GPS positioning and the positioning time based on the autonomous positioning are unified with the GPS positioning time, there is no error when switching the positioning method.

(2) Since the positioning time is added to the obtained latitude and longitude and stored, it is possible to unify the time with the measurement information output from other measuring devices, and a route measurement suitable for measuring the physical quantity distribution can be performed. realizable.

(3) GP after the receiving state has been successfully restored
Since the correction by the S positioning is performed, it is possible to improve the low precision latitude and longitude by the autonomous positioning. Therefore, even if a relatively low-precision sensor is used for the autonomous positioning, the traveling route can be measured with high accuracy.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a moving body traveling route measurement system according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vehicle (moving body) 2 GPS receiver (GPS positioning means) 3 Vehicle speed sensor 4 Optical gyro 5 Autonomous navigation unit (autonomous positioning means) 6 Host computer (positioning information storage means)

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F002 AA00 AF01 BB04 FA16 GA06 2F029 AA02 AA07 AB01 AB07 AB09 AC02 AC14 AC16 AD01 5H180 AA01 AA21 BB15 CC01 FF04 FF05 FF07 FF22 FF32 5J062 AA01 AA13 BB01 FF00 DD03

Claims (4)

[Claims] 1. GPS positioning means for obtaining a latitude and longitude where a mobile body is located by receiving a satellite radio wave, and outputting positioning information obtained by adding the positioning time at which the satellite radio wave was received and the current time to the latitude and longitude, A positioning information storage unit that stores the positioning information; a sensor that detects an angle and a moving distance of the moving body; and an autonomous positioning unit that obtains a position change within a desired time from the detection information of the sensors. When the reception state of the satellite radio wave in the means becomes poor, the positioning information storage means adds the positioning time immediately before the reception state becomes poor and stores the latitude and longitude by GPS positioning, A moving body traveling route, wherein a latitude and longitude are obtained by adding a position change by autonomous positioning at a coincident time, and the latitude and longitude by autonomous positioning are stored in the positioning information storage means. Measurement system. 2. The method of claim 2, wherein the latitude / longitude of the autonomous positioning among the latitude / longitude stored in the positioning information storage means is the latitude / longitude of the GPS positioning before the reception state becomes poor, and the GPS positioning after the reception state is satisfactorily restored. 2. The moving body traveling route measuring system according to claim 1, wherein the correction is made by the latitude and longitude of the moving object. 3. An azimuth difference and a distance difference are obtained from a latitude and longitude based on GPS positioning after the reception state has been restored satisfactorily and a latitude and longitude based on autonomous positioning immediately before the reception state has been restored satisfactorily. Are averaged to determine the detection error of the sensor over the period during which the reception state is poor, and the detected information of the sensor corrected by the detection error and the latitude and longitude obtained by the GPS positioning before the reception state becomes poor are used. 3. The mobile object traveling route measurement system according to claim 1, wherein the latitude and longitude by autonomous positioning during a period in which the reception state is poor are calculated again, and the latitude and longitude are stored again in the positioning information storage means. . 4. A positioning information storage means, wherein information for discriminating between latitude and longitude based on GPS positioning and latitude and longitude based on autonomous positioning is added to positioning information and stored in said positioning information storage means.
3. The moving body traveling route measurement system according to any one of 3).