JPH0943336A - Relative position measurement method - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide a method for accurately measuring a relative position or a relative distance between vehicles using GPS signals from GPS satellites. SOLUTION: Vehicles 10 and 2 that travel back and forth on a road.
0 has GPS antennas 11 and 22, own vehicle position calculation devices 12 and 22, inter-vehicle communication devices 13 and 23, ground antennas 14 and 24, and follow-up traveling devices 15 and 25, respectively, and the GPS antenna 11 receives them. The vehicle position calculation device 12 calculates the current position of the vehicle 10 based on the GPS signal, and the ground antenna 14 transmits synchronization signal information of the current position and the GPS signal. 20 calculates the current position of the vehicle 20 by the own vehicle position calculation device 22 based on the same GPS signal, and calculates the relative position or relative distance between the vehicles 10 and 20 from both current positions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring relative positions between moving bodies such as vehicles using GPS satellites.

[0002]

2. Description of the Related Art GPS (groval positioning system)
As an apparatus for measuring the position of a moving body such as a vehicle using a satellite, as shown in Japanese Utility Model Publication No. 4-20808, the current position of the vehicle is measured by a positioning radio wave from a GPS satellite. A technology for displaying the current position information of the own vehicle to another vehicle and simultaneously displaying the current position information of the other vehicle received from the other vehicle on the navigation device of the own vehicle while displaying its position on the navigation device of the own vehicle Is known,
In this case, the GPS is used to measure the current position of the vehicle.
Since there is no synchronization between the positioning radio wave received from the satellite and the positioning radio wave received from the GPS satellite to measure the current position of another vehicle, an error may occur in the relative position measurement of both vehicles. Therefore, it is difficult to accurately perform relative control between the two vehicles based on these signals.

[0003]

SUMMARY OF THE INVENTION The present invention is intended to provide a method for accurately measuring a relative position or a relative distance between moving bodies such as vehicles using GPS signals from GPS satellites. .

[0004]

Therefore, in the relative position measuring method according to the present invention, the first moving body receives the positioning radio wave from the GPS satellite and calculates the current position of the first moving body. , The current position information and the synchronization information of the positioning radio wave are transmitted, the second mobile body receives the current position information and the synchronization information from the first mobile body, and the positioning of the synchronization information is performed. The current position of the second moving body is calculated by the positioning radio wave from the GPS satellite synchronized with the reception of the radio wave for use,
The relative position or the relative distance between the two moving bodies is calculated based on the received current position information of the first moving body and the calculated current position of the second moving body.

That is, the first mobile unit receives the positioning radio wave from the GPS satellite, calculates the current position thereof, and outputs the current position information transmitted from the first mobile unit and the synchronization information of the positioning radio wave reception. When the two moving bodies receive, the current position of the second moving body is calculated in synchronization with the current position information of the first moving body, and the relative position or the relative distance between the two moving bodies is calculated based on the both current positions. Since the current position of each moving body is calculated by the synchronous positioning radio wave, the relative position or the relative distance between both moving bodies can be accurately calculated.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention shown in the drawings will be described below. 1 and 2, the road 1
Vehicle 10 and vehicle 20 traveling in the same direction in front of and behind
Are equipped with GPS antennas 11 and 21, vehicle position calculation devices 12 and 22, inter-vehicle communication devices 13 and 23, ground antennas 14 and 24, and follow-up traveling devices 15 and 25, respectively.

The vehicle 10 has at least three GPS satellites A, B, C and D, usually four, by means of GPS antennas 11.
GPS signals that are positioning radio waves from
Based on this GPS signal, the vehicle position calculation device 12 presents the current position of the vehicle 10, that is, the three-dimensional absolute coordinates (x) indicating the longitude, latitude and altitude at which the vehicle 10 currently exists.
1, y1, z1) are calculated, and at the same time, the three-dimensional vehicle speed v1 is also measured.

Further, the vehicle 10 uses the GPS signal for the above calculation, the satellite numbers of the GPS satellites A, B, C, and D, the reception synchronization signal for each GPS signal, and the absolute coordinates indicating the current position of the vehicle 10. (X1, y1, z1), and
Information on the vehicle speed v1 is transmitted from the ground antenna 14 by the inter-vehicle communication device 13.

Since the GPS signals from the GPS satellites A, B, C and D are transmitted at regular intervals, G
The sending of the reception synchronization signal for the PS signal is also interrupt-transmitted at the above-mentioned fixed time intervals, and the operation routine of the system mounted on the vehicle 10 is shown in FIG.

Vehicle 2 traveling behind vehicle 10
0 is at least three GPS satellites A, B, C, D by the GPS antenna 21 like the vehicle 10.
GPS signals are respectively fetched from the vehicle, and the current position of the vehicle 20 is calculated by the vehicle position calculation device 22 based on the GPS signals, that is, three-dimensional absolute coordinates indicating the longitude, latitude and altitude at which the vehicle 20 is currently present. (X2, y2, z2)
At this time, based on the reception synchronization signal of the vehicle 10 taken into the inter-vehicle communication device 23 by the ground antenna 24, the absolute coordinates (from the same GPS satellites from the same GPS satellites A, B, C, D) are calculated. x2, y2, z2)
Is calculated, the three-dimensional vehicle speed v2 is also measured.

The vehicle 20 is a vehicle 1 traveling in front.
Current position coordinates of 0 (x1, y1, z1) and vehicle speed v
The information of 1 is transmitted to the inter-vehicle communication device 2 by the ground antenna 24.
3, and the current position coordinates of the vehicle 20 (x2, y2,
z2) and the own vehicle speed v2, the relative position and / or the relative distance to the vehicle 10 and the relative speed can be calculated.

Further, the following traveling device 15 of the vehicle 20 is
Based on the relative position and / or the relative distance and the relative speed, the vehicle 20 while considering the vertical gradient and the left and right curves of the road 1 from the three-dimensional relative positions of the vehicle speeds v1, v2 and the vehicle 10 and the like. In the so-called follow-up traveling control, which keeps a constant distance from the vehicle 10 on a highway, a curved road, etc. by controlling the output of the engine, controlling the braking force, etc.
FIG. 4 shows an operation routine of a system mounted on the vehicle 20 for the purpose of saving the driver's labor.

Further, contrary to the above case, the vehicle 20 takes in GPS signals from the GPS satellites A, B, C and D by the GPS antenna 21, and the own vehicle position calculating device 22 makes the vehicle 20 based on the GPS signals. The current position coordinates (x2, y2, z2) of the vehicle 20 are calculated, the own vehicle speed v2 is measured, and the satellite numbers of the GPS satellites A, B, C, D using the GPS signals for the above calculation, their GPS Received synchronization signal about the signal, the current position coordinates of the own vehicle 20 (x2,
y2, z2) and the information of the vehicle speed v2 are transmitted from the ground antenna 24 by the inter-vehicle communication device 23,
The vehicle 10 has an inter-vehicle communication device 1 through a ground antenna 14.
Based on the reception synchronization signal of the vehicle 20 taken in
Synchronous GPS signals from the same GPS satellites A, B, C, D are fetched by the GPS antenna 11, and the current position coordinates (x1, y1, z of the own vehicle 10 are calculated by the own vehicle position calculation device 12.
At the same time as calculating 1), the own vehicle speed v1 is also measured, and the current position coordinates (x2, y2, z2) of the vehicle 20 and the own vehicle speed v2, which are taken into the inter-vehicle communication device 13 by the ground antenna 14, Current position coordinates of the car 10 (x1, y
1, z1) and the vehicle speed v1
The relative position and / or the relative distance to the vehicle 20 and the relative speed are calculated, and the following traveling device 25 controls the output of the engine in the vehicle 10, the braking force control, and the like based on the relative position and / or the relative distance and the relative speed. Thus, it is possible to perform follow-up running control for keeping a constant distance from the vehicle 20 on a highway or the like.

In these cases, GPS satellites A, B, C, D using GPS signals for calculating the current position of the vehicle
By receiving and transmitting not only the satellite numbers of the GPS signals but also the respective GPS reception synchronization signals, the current position coordinates (x1, y1, z1) and the current position coordinates (x2, y2, z2) of the vehicle 10 and the vehicle 20 are transmitted. ) Are calculated by synchronous GPS signals from the same GPS satellites A, B, C, D, respectively, so that their current position coordinates (x1, y1, z1),
A very accurate value can be obtained for the relative position and / or the relative distance of the vehicles 10, 20 calculated from (x2, y2, z2).

Moreover, based on the GPS signals taken in by the vehicle 10 and the vehicle 20 by the GPS antennas 11 and 21, respectively, the own vehicle position calculating devices 12 and 22 respectively calculate the present position coordinates (x1, y1) by different calculation expressions.
, Z1), (x2, y2, z2) are calculated, even if there is a slight deviation between the coordinates of both current positions, the GPS satellites A, B, which are transmitted at regular intervals,
If the information is exchanged between the vehicles 10 and 20 based on the GPS signals from C and D or every plural times, and the calculation of the current position coordinates is repeated, the generated error will occur each time. Since the correction is performed, the calculated relative position and / or relative distance error is not accumulated, and the accuracy of the relative position and / or relative distance is ensured.

Therefore, the follow-up running devices 15 and 25 can easily perform follow-up running control of the vehicles 10 and 20 based on the accurate relative position and / or relative distance and relative speed between the vehicles 10 and 20. Become.

In the vehicle 10 and the vehicle 20, the current position coordinates (x1, y1, z1) and the current position coordinates (x2, y2, z2) respectively obtained, and the vehicle speed v1 and the vehicle speed v2 are respectively obtained. The current position coordinates (x1, y1, z1) obtained from the driver's seat, etc.
Needless to say, it can be used as a navigation system by displaying the current position coordinates (x2, y2, z2) on the display device in association with each other.

It should be noted that each vehicle cannot always receive GPS signals from the same GPS satellite according to its traveling position, but it does not always receive GPS signals from the same GPS satellite based on the reception synchronization signal. Since the current position coordinates of the vehicle are calculated, the position can be accurately calculated. Further, although the above-described embodiment has been described with respect to the front and rear two vehicles, the present invention is similarly applied to a larger number of vehicles. Further, the present invention can be applied not only to passenger cars and trucks as vehicles, but also to moving objects such as motorcycles, bicycles, and ships.

[0019]

As described above, according to the relative position measuring method of the present invention, the current positions of the first moving body and the second moving body are calculated in synchronization by using the positioning radio waves from the GPS satellites. By doing so, the relative position or the relative distance between the two moving bodies can be calculated extremely accurately, and therefore, the following traveling control of the moving body can be easily performed by an appropriate following traveling device. .

[Brief description of drawings]

FIG. 1 is a conceptual explanatory diagram according to an embodiment of the present invention.

FIG. 2 is a schematic layout diagram of the embodiment example.

FIG. 3 is an operation flowchart of a main part of the embodiment described above.

FIG. 4 is an operation flowchart of a main part of the embodiment described above.

[Explanation of symbols]

 1 Road 10 Vehicle 11 GPS Antenna 12 Vehicle Position Calculator 13 Inter-Vehicle Communication Device 14 Ground Antenna 15 Tracking Traveling Device 20 Vehicle 21 GPS Antenna 22 Vehicle Position Calculating Device 23 Inter-Vehicle Communication Device 24 Ground Antenna 25 Tracking Traveling Device A ~ D GPS satellite

Claims (5)

[Claims] 1. A first mobile unit receives positioning radio waves from GPS satellites to calculate a current position of the first mobile unit, and transmits the current position information and synchronization information for receiving the positioning radio waves. Then, the second mobile unit receives the current position information and the synchronization information from the first mobile unit and uses the positioning radio wave from the GPS satellite synchronized with the positioning radio wave reception of the synchronization information. The current position of the mobile unit is calculated, and the relative position or the relative distance between the two mobile units is calculated based on the received current position information of the first mobile unit and the calculated current position of the second mobile unit. The relative position measuring method. 2. The first moving body and the second moving body according to claim 1, wherein respective current positions of the first moving body and the second moving body are calculated based on positioning radio waves from the GPS satellites or every plural times, and A relative position measuring method in which a second moving body calculates a relative position or a relative distance between the two moving bodies based on the both current positions. 3. The GPS satellite according to claim 1 or 2, wherein the GPS satellite from which the first mobile body receives positioning radio waves and the GPS satellite from which the second mobile body receives positioning radio waves are the same. Is a relative position measuring method. 4. The relative position measuring method according to claim 1, wherein the second moving body follows the rear of the first moving body and moves. 5. In any one of claims 1 to 4, based on the calculated relative position or relative distance between the two moving bodies and / or the relative velocity measured thereby,
A follow-up movement control method for controlling the movement of the second moving body so that the second moving body follows the first moving body.