JPH01221687A - Guiding method for vehicle - Google Patents

Abstract

PURPOSE:To accurately find the relative position of a vehicle to a fixed reference station by finding the relative position of the vehicle to the fixed reference station with distance measurement data based upon position data on the vehicle and position data on the fixed reference station. CONSTITUTION:A controller 6 mounted on the vehicle finds the current position data on the vehicle by a GPS receiver 14. A transmitter receiver 16 sends a command and the distance measurement data based upon the position data to the fixed reference station. The fixed reference station 18 receives the command and distance measurement data from the vehicle by a transmitter receiver 21. A GPS receiver 20 finds the current position data on the fixed reference station. A computer 19 finds the relative position of the vehicle to the fixed reference station with the distance measurement data based upon the position data on the vehicle and the position data on the fixed reference station. Then the position of the vehicle is accurately found because the fixed reference station is provided fixedly at a prescribed position.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for guiding a vehicle that runs unmanned outdoors, such as a lawnmower on a golf course.

2. Description of the Related Art Conventionally, when guiding an unmanned vehicle, a gyro, an encoder, or the like is used to detect the traveling direction and distance to control the vehicle's speed, steering angle, etc. At this time, positional errors due to errors of each detection sensor accumulate, so the errors are corrected by providing markers here and there that serve as positional references. Alternatively, the vehicle can travel without accumulating errors by constantly receiving signals from traffic signs without using a gyro or the like.

Issues to be Solved by the Invention However, with such conventional systems, signs must be placed accurately to correct for errors, and it is difficult to move the signs, resulting in a lack of flexibility. There's a problem. Another problem is that when this sign is installed outdoors, it must be able to withstand sunlight, wind, rain, and other environments.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve such problems and to enable vehicles to be guided with high accuracy without installing conventional signs.

Means for Solving the Problems In order to solve the above problems, the present invention provides the following features: When the vehicle is driven while communicating between a fixed reference station and the vehicle,
A first GPS receiver mounted on the vehicle obtains position data of the vehicle, and distance measurement data based on this position data is transmitted from the vehicle to a fixed reference station, and a second GPS receiver installed at the fixed reference station is transmitted. The position data of this fixed reference station is determined by a receiver, and the relative position of the vehicle with respect to the fixed reference station is determined from the position data of the vehicle and distance measurement data based on the position data of the fixed reference station.

In addition, the present invention uses GPS to determine the relative position of the vehicle with respect to a fixed reference station, then moves the vehicle straight a certain distance, determines the relative position of the vehicle with respect to the fixed reference station after traveling straight through GPS, and calculates the relative position of the vehicle with respect to the fixed reference station before and after traveling straight. The direction of travel of the vehicle is determined from the position data at .

Further, in the present invention, when the vehicle is driven toward a measurement point set at an appropriate location while communicating between the fixed reference station and the vehicle, the travel map and travel program are used until the vehicle reaches the measurement point. Calculate the driving route according to the following, drive the vehicle, and when you reach the measurement point,
Determine the relative position of the vehicle with respect to a fixed reference station using GPS, determine the error between the position of the measurement point and the position of the vehicle,
Next, the vehicle is driven straight for a certain distance, and the traveling direction of the vehicle is determined from the difference between the position after going straight and the position before going straight, which is determined by GPS. Based on the traveling direction data, the traveling route toward the next measurement point is corrected, and then the vehicle is driven toward the next measurement point.

Further, in the present invention, the vehicle is moved to a position to be set as a measurement point, the relative position of this position to be set with respect to a fixed reference station is determined by GPS, and the data of this relative position is registered as measurement point data.

Global Positionin
gSysten) is a system that receives ranging signals from ranging satellites launched all over the world and detects positions.

The absolute position detection accuracy is about 10 to 20 m, but the relative position can be detected on the order of several square meters.

Therefore, according to the present invention, the relative position of the vehicle with respect to the fixed reference station can be determined with high accuracy, and the traveling direction of the vehicle can also be determined. Furthermore, the vehicle can be guided toward the measurement point with high accuracy without installing specific signs outdoors, and cumulative errors in position during driving can be eliminated. Furthermore, setting and changing measurement points can be done very easily since it is only necessary to move the vehicle to the point and register it.

In the above, "position data" refers to data sent from ranging satellites, and its contents include satellite position, time, distance measurement correction data, etc. On the receiver side,
From them, the absolute position of the receiver is calculated. Also"
"Distance measurement data" refers to data on the absolute position of the receiver.

Embodiment In FIG. 6, reference numeral 1 denotes a fixed reference station, which is fixedly provided at a predetermined position. 2 is an unmanned vehicle,
It is possible to communicate with the fixed reference station 1. At any position where the vehicle 2 can travel, there are a plurality of measurement points 3a,
3b, . . . are set.

FIG. 1 shows the configuration of a control device 5 mounted on a vehicle 2. As shown in FIG. This control device 5 is provided with a controller 6 such as a CPU, and this controller 6 includes a speed controller 7 for controlling the speed of the vehicle 2 and a steering controller 8 for controlling the traveling direction of the vehicle 2. It is connected. Further, various sensors 9 such as a distance sensor for detecting the traveling distance of the vehicle 2, a gyrocator for detecting the traveling direction of the vehicle 2, and an ultrasonic sensor are connected to the controller 6. Reference numeral 10 denotes a memory for running data, which has a running map 11 that stores data related to running locations and a measurement point data section 12 that stores data related to measurement points, and is connected to the controller 6. . Reference numeral 13 denotes a memory for a driving program, which stores data for determining the driving route of the vehicle 2, and is connected to the controller 6.

A GPS receiver 14 is capable of receiving ranging signals from ranging satellites via an antenna 15, and is connected to the controller 6. A transceiver 16 is capable of communicating with the fixed reference station 1 via an antenna 17, and is connected to the controller 6.

FIG. 2 shows the configuration of a control device 18 provided in the fixed reference station 1. This control device 18 is provided with a calculation unit 319 for performing various calculations, and this computer 19 has a
An S receiver 20 and a transceiver 21 are connected. GP
The S receiver 20 transmits the ranging signal from the ranging satellite to the antenna 22.
The transmitter/receiver 21 can receive data via the antenna 23.
It is possible to communicate with the transceiver 16 on the vehicle 2 side via the transceiver 16 on the vehicle 2 side.

Next, a method for detecting the position of the vehicle 2 using GPS will be explained based on FIG. 4. When the controller 6 mounted on the vehicle 2 starts detecting the position by GPS in step 41, in step 42,
At step 43, the GPS reception 8114 determines the current position data of the vehicle 2. In step 43, the transceiver 16 transmits a command and ranging data based on the position data to the fixed reference station 1.

On the other hand, in the fixed reference station 1, once the relative position calculation is started in step 44, in step 45, the command and distance measurement data from the vehicle 2 are received by the transceiver 21. The position data of the fixed reference station 1 at that time is determined by the GPS receiver 20. Then, in step 47, the computer 19 calculates the relative position of the vehicle 2 with respect to the fixed reference station 1 based on the position data of the vehicle 2 and the distance measurement data based on the position data of the fixed reference station 1. Then, since the fixed reference station 1 is fixedly provided at a predetermined position, the position of the vehicle 2 can be accurately determined. Thereafter, in step 48, the transmitter/receiver 21 transmits relative position data toward the vehicle 2, and in step 49, the operation is completed.

In step 50, the vehicle 2 receives relative position data from the fixed reference station 1 through the transceiver fi 16, recognizes its own position, and ends the work in step 51.

Next, the operation of determining the traveling direction of the vehicle 2 will be explained based on FIG. 5. When the position of the vehicle 2 is detected by the operation shown in FIG. 4, and the detection of the traveling direction is started in step 61, the steering angle is set to 0 degrees by the steering controller 8 of the vehicle 2 in step 62. Next, in step 63, the vehicle 2 is made to go straight for several meters, and after going straight, in step 64, the position of the vehicle 2 is detected by GPS in the same manner as in FIG. 4 (see the virtual line in FIG. 6), and , by step 65,
The moving direction of the vehicle 2 is determined by the computer 19 of the fixed reference station 1 from the position data before and after going straight, and step 66
Finish the work.

Figure 3 shows measurement points 3a + 3b shown in Figure 6.
A method for guiding the vehicle 2 when the vehicle 2 is driven using the following will be explained.

First, when the work is started in step 71, in step 72, the controller 6 calculates the driving route based on the driving map 11 in the memory 10 of the vehicle 2 and the driving program in the memory 13.Next, in step 73, the controller 6 calculates the driving route. , the position of the vehicle 2 at that time is determined by GPS using the method shown in FIG. Further, in step 74, the traveling direction of the vehicle 2 at that time is determined by GPS using the method shown in FIG. Thereafter, using the data on the position and traveling direction of the vehicle 2 determined above, in step 75, the traveling route to the measurement point 3a (see FIG. 6) is corrected.

Once the travel path has been corrected, in step 7G the vehicle 2
is started, and in step 77 steering control and speed control are performed, and in step 7
At step 8, the vehicle 2 is driven toward the measurement point 3a while the position of the vehicle 2 is detected by the gyrocator and the distance sensor. Then, in step 79, measurement point 3
A determination is made as to whether a has been reached. If the measurement point 3a has not yet been reached, the vehicle continues traveling toward the measurement point 3a while repeating the steering control and speed control in step 77 and the position detection in step 78.

When the measurement point 3a is reached, in step 80 the vehicle 2
to stop. Then, in step 73, the vehicle 2 at that time
Detects the position of the measurement point 3a and the true position of the vehicle 2.
Find the error from the actual stop position. Then, the running direction of the vehicle 2 at that time is determined again in step 74, and based on this running direction data and the above-mentioned position error data, in step 75, the running route to the next measurement point 3b is corrected. Thereafter, the vehicle 2 continues to run while repeating the same operations as above.

When setting or changing the measurement points 3a, 3b, etc., move the vehicle 2 to the position to be the new measurement point, calculate the relative position of this position with respect to the fixed reference station 1 by the method shown in FIG. This relative position data may be registered in the measurement point data section 12 of the memory 10 as measurement point data.

As described above, according to the present invention, by using GPS, the vehicle 2 is guided while correcting the cumulative errors of the gyrocator and distance sensor. Furthermore, since the calculation of the position by GPS is performed by the calculation tR19 provided in the fixed reference station 1, there is an advantage that there is no need to mount an expensive computer on the vehicle 2.

Note that if a high-precision gyro is used as the sensor 9 and the distance between the measurement points is set appropriately short, very highly accurate guidance is possible.

Effects of the Invention As described above, according to the present invention, it is not only possible to accurately determine the relative position of a vehicle with respect to a fixed reference station, it is also possible to determine the direction of travel of the vehicle, and it is also possible to direct the vehicle toward a measurement point. We were able to guide all vehicles 11 times without installing signs outdoors.
Accumulated errors in the position of the vehicle during driving can be removed.

Furthermore, measurement points can be set and changed very easily.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a block diagram of a control device mounted on a vehicle, Fig. 2 is a block diagram of a control device on the fixed reference station side, and Fig. 3 is a block diagram of a control device mounted on a vehicle. FIG. 4 is a flow diagram showing a method for detecting the relative position of a vehicle with respect to a fixed reference station; FIG. 5 is a flow diagram showing a method for detecting the running direction of a vehicle.
FIG. 6 is a plan view showing a method of guiding a vehicle traveling toward a measurement point. 1...Fixed reference station, 2...Vehicle, 3a, 3b...
Measurement point, 11... Driving map, 12... Measurement point data section, 14.20... GPS receiver, 1
6.21...transmitter/receiver, 19...total 'jL machines. Agent Yoshihiro MorimotoFigure 1Figure 3Figure 4Figure 5Figure 5

Claims (1)

[Claims] 1. When the vehicle is traveling while communicating between the fixed reference station and the vehicle, the position data of the vehicle is determined by a first GPS receiver mounted on the vehicle, and the position data of the vehicle is determined. The distance measurement data based on the data is transmitted from the vehicle toward the fixed reference station, the position data of this fixed reference station is obtained by a second GPS receiver installed in the fixed reference station, and the position data of the vehicle and the position of the fixed reference station are determined. A vehicle guidance method characterized by determining the relative position of the vehicle with respect to a fixed reference station using distance measurement data based on the data. 2. Determine the relative position of the vehicle with respect to the fixed reference station using GPS. Next, drive the vehicle straight a certain distance, determine the relative position of the vehicle with respect to the fixed reference station after traveling straight using GPS, and calculate the position of the vehicle from the position data before and after traveling straight. 2. The vehicle guidance method according to claim 1, further comprising determining the traveling direction of the vehicle. 3. While communicating between the fixed reference station and the vehicle, when driving the vehicle toward a measurement point set at an appropriate location, the vehicle must drive according to the driving map and driving program until it reaches the measurement point. After calculating the road and driving the vehicle, when it reaches the measurement point, the relative position of the vehicle to the fixed reference station is determined using GPS, the error between the position of the measurement point and the vehicle position is determined, and then the vehicle is kept at a constant position. The vehicle is driven straight for the same distance, and the traveling direction of the vehicle is determined from the difference between the position after going straight as determined by GPS and the position before going straight, and data on the error in the position between the measurement point and the vehicle and data on the traveling direction of the vehicle are obtained. 3. The method of guiding a vehicle according to claim 1, further comprising: correcting a travel route toward the next measurement point by the following steps; and then causing the vehicle to travel toward the next measurement point. 4. While communicating between the fixed reference station and the vehicle, when driving the vehicle toward the measurement point, move the vehicle to the position to be set as the measurement point, and set the position relative to the fixed reference station at this position to be set. 4. The vehicle guidance method according to claim 1, wherein the relative position is determined by GPS, and the data of this relative position is registered as measurement point data.