JPS62226205A - Drive guiding device for unmanned carrier - Google Patents

Abstract

PURPOSE:To attain the autonomous drive of an unmanned carrier with high accuracy by an inexpensive gyroscope by correcting an error due to the drift of the gyroscope, etc. through the steering control based on two detecting means for gradient and position shift of the carrier. CONSTITUTION:An unmanned carrier 1 contains a pair of drive wheels 2, 3, drive motors 4 and 5, etc. While a drive guiding device consists of an angle detector 20 containing a gas rate gyroscope 10, etc., a drive position shift detector 11, a drive gradient detector 14, a drive control CPU 24, a driving path pattern memory 23, etc. and controls both motors 4 and 5 so that the reference direction is always coincident with the reference distance. Then both the gradient and the position shift of the carrier 1 are detected at a prescribed point every time the data on the travelled distance is equal to the prescribed value. The speed difference between both wheels 2 and 3 is calculated for corrected drive based on the results of detection of both detectors 11 and 14. Thus the gradient and position shift of the carrier 1 can be eliminated. Then the drive of the carrier 1 is corrected based on the results of said operations and the accumulation of errors can be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a travel guidance device for an unmanned vehicle that is introduced into factories, warehouses, etc. for the purpose of transporting goods.

[Conventional technology]

The guidance method for the above-mentioned unmanned vehicle (hereinafter simply referred to as unmanned vehicle) is to lay a guide wire such as an electromagnetic induction wire or optical tape on the driving route, and detect the position of the guide wire with a detector on the unmanned vehicle. Currently, there are many methods of controlling the steering of unmanned vehicles so that they follow the guidance lines, so-called fixed-route guidance methods for unmanned vehicles.

On the other hand, many routeless guidance systems have been developed and proposed in order to realize more free driving. Among the routeless guidance methods, there is an autonomous driving method using a gyro,
In other words, the gyro is used to detect azimuth data in the driving direction, and the steering is controlled while comparing the azimuth data and distance data calculated from the amount of wheel rotation with data previously stored in the unmanned vehicle. There is.

[Problem that the invention seeks to solve]

However, in the autonomous driving system using the above-mentioned gyros, high-precision ones are expensive and impractical, and on the other hand, the gyros that are currently available (e.g. gas rate gyros and vibration gyros) are not yet accurate enough. However, autonomous driving based only on gyros was difficult to achieve.

[Means for solving problems]

The present invention is an autonomous driving system using the above-mentioned gyro, and includes means for detecting the inclination of an unmanned vehicle every time it travels an arbitrary predetermined distance, means for detecting a positional shift of the unmanned vehicle, and a means for detecting the two detections. and means for performing steering control to correct a running error of the unmanned vehicle based on the output from the means.

[Effect]

Driving errors due to gyro drift, wheel slip, etc. are corrected by steering control based on the outputs of the two detection means.

〔Example〕

FIG. 5 is a diagram schematically showing an embodiment of an unmanned vehicle to which the present invention is applied, and this unmanned vehicle (1) has a pair of drive wheels (2) on the left and right sides of the approximately central position in the longitudinal direction of the vehicle body. 3) is provided, and the drive wheels (2) (3) are provided with a travel motor (4).
) (5) are directly connected to each other. This unmanned car (1)
The vehicle enables cornering by making the rotation speeds of the left and right drive wheels (2) and (3) different. (6) and (7) respectively indicate the brakes for decelerating or stopping the drive wheels (2) and (3), and (8) and (9) respectively indicate the brakes for the drive wheels (2) and (3).
2) Shows the pulse generator that detects the rotation speed in (3). (10) shows a known gas rate gyro, which makes it possible to detect angular velocity using Coriolis acceleration, and the direction of the unmanned vehicle (1) while traveling is determined every unit time. (For example, every second) is measured by the gas rate gyro and compared with a pre-stored reference direction, and the speed of both drive transports (2) and (3) is controlled so that it always matches the reference direction. conduct.

(11) is the light emitter (12) and the light receiving element array C
A running position deviation detector consisting of CD (13) is shown, (
Reference numeral 14) indicates a travel inclination detector consisting of a COD, which is a light receiving element array, and the CCD (14) receives light projected from a light projector (15) installed on the ground side. In addition, (16
) indicates a driven wheel supported on the vehicle body in a caster-like manner.

FIG. 1 shows a block diagram of the travel control system of the unmanned vehicle (1), in which (20) is an angle detector;
A gas rate gyro (10) that measures the direction while driving, an A/D converter (21) that converts the analog output output from the gyro (10) into a digital output, and an unmanned vehicle ( 1) and an angle calculation CPU (22) that calculates the orientation. Direction data (il) of the unmanned vehicle (1) sent from the angle detector (20) every unit time (for example, every second) and every unit time stored in advance in the travel path pattern memory (23) The reference direction data (12) of the travel control CPU (2
4) and similarly pulse generator (8)
The distance data (i3) (i4) detected in (9) and the reference distance data (i5) (i6) stored in advance in the travel route pattern memory (23) are sequentially transmitted to the travel control CP t.
J (24), the speed ratio of both drive transports (2) and (3) is controlled so that it always matches the reference direction and reference distance, and the control command (17) is transmitted to the above-mentioned traveling agent '4it.
It is sent from the CPU (24) to the servo CPU (25). (26) and (27) indicate the servo driver, (
4) (5) each indicates a drive motor.

Next, the principle of detection by the traveling position deviation detector (11) will be explained based on FIG. The solid line indicates the detector (11) when the unmanned vehicle (1) is not deviated from its driving position, and the dashed line (lla) indicates the case where the unmanned vehicle (1) is deviated from the solid line position.
(llb) respectively. When in a predetermined position, the light projected from the light projector (12) is reflected by the side wall (W) and enters the light receiving element (rl) of the COD (13).

Distance (d) from the light emitter (12) to the light receiving element (rl)
) and the distance (14>) from the floodlight (12) or CCD (13) to the side wall (W) can be given in advance. Now, suppose the unmanned vehicle (1) deviates from the predetermined position by a distance (Δl). Naturally, the detector (lla) also deviates from the predetermined position by a distance (△β), and assuming that the light emitted from the light emitter (12a) is always parallel, the light receiving element (r2) of the CCD (13a) and the above If the distance to the light receiving element (rl) at a predetermined position is (△d), then d
Two △d; l: △l, and △β is △p=ZXΔd/d
It is given by the formula.

Next, based on Figure 3.4, the running inclination detector (14)
The principle of detection will be explained below. Floodlight installed on the side wall (
The COD (14) receives two lights emitted at a unit time (1) interval by 15). Even if the above time (1) interval is set on the timer on the projector (15), COD
You may also set the timer in (14). The above time (
1) During this period, the unmanned vehicle (1) travels for a predetermined length of l (m). Third.
For the sake of explanation, in Figure 4, the CCD (14) is fixed and the projector (15) is moved, but in reality it is the opposite. FIG. 3 shows a case where there is no tilt shift, and the distance at between the two light receiving elements (r3) (r4) is (m). Fig. 4 shows a case where a deviation in the slope (θ) occurs.
Although the above distance (m) does not change, the distance between the two light receiving elements (r5) (r6)) becomes (n). Therefore, the value of the slope (θ) is given by the formula cosθ=m/n.

Since the value of the inclination (θ) is given regardless of the positional deviation of the unmanned vehicle (1), the positional deviation value <Δl) is calculated and corrected based on the value of the inclination (θ).

In the present embodiment described above, the traveling position deviation detector (11
) and the travel inclination detector (14) are performed using the side walls of the travel path of the unmanned vehicle, but the floor surface of the travel path or the ceiling may be used depending on the case. .

The driving side of the unmanned vehicle (1) configured as above? B C
The processing operation flow of P U (24) will be explained using FIG. 6. First, when the driving of the unmanned vehicle (1) is started in step (2), steps (2) to (2) are executed as follows.

Step ■■: Simultaneously with the start of driving, the rotational speed of the driving wheels (2) and (3) is input from the pulse generators (8) and (9), respectively, and from the rotational speed, the traveling distance data of the unmanned vehicle (1) and the turning Angle data and velocity data are output. After a unit of time has elapsed due to the action of a timer, etc., the process proceeds to the next step.

Step ■■: After the above unit time has passed, the gyro (10
), and the direction data and the travel distance data are each compared with reference data.

Step ■■■: If the two match according to the above comparison, continue traveling without correction, and if they do not match, calculate the speed correction of both station driving wheels (2) and (3) so that they match, and Correct based on the calculation result.

Normally, as described above, the unmanned vehicle (1) performs guided running (te), but errors in running accumulate due to drift of the gyro (10), wheel slip, etc. Therefore, if! In order to correct the error, the following processing is performed. (Refer to the processing flow in Figure 7.) Step ■ [Phase] 0◎0: Pulse generator (8)
(9) Every time the travel distance data sent from
and positional deviation (△2) are detected, and based on the two detected values (θ) (△e), the two stations are determined for corrective travel to eliminate the deviation (△I). The speeding up of the driving wheels (2) and (3) is calculated, and the running of the unmanned vehicle (1) is corrected based on the 7Ei calculation result.

Step 0■: After the above correction, the traveling distance and traveling direction of the unmanned vehicle are set to prevent the accumulation of errors.

In addition, in the above embodiment, although the inclination and positional shift of the unmanned vehicle are detected using light, they may be detected using laser light, sound waves, or the like.

〔Effect of the invention〕

As explained above, according to the present invention, even if an inexpensive gyro with insufficient accuracy is used, reliable and reliable autonomous driving of an unmanned vehicle along a predetermined route is enabled.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a driving control system of an unmanned vehicle to which an embodiment of the present invention is applied, and Fig. 2 is a schematic diagram illustrating the principle of detecting positional deviation of an unmanned vehicle by a driving position deviation detector. , Fig. 3 is a schematic diagram for explaining the principle of detecting the inclination of an unmanned vehicle using a running inclination detector, Fig. 4 is also a schematic diagram, and Fig. 5 shows an embodiment of an unmanned vehicle to which the present invention is applied. FIG. 6 is a schematic plan view, FIG. 6 is a flowchart showing the processing operation flow of the driving control CPU of the unmanned vehicle, and FIG. 7 is a flowchart showing the processing operation flow for correcting cumulative errors caused by driving. <1)...Unmanned vehicle (8)(9)...Pulse generator (10)...
Gyro (11)... Traveling position deviation detector (14)... Traveling inclination detector (23)... Traveling path pattern memory (24)... Traveling control CPU Cold 2 Figure A7

Claims (1)

[Claims] A gyro mounted on the unmanned vehicle detects azimuth data of the unmanned vehicle, and the azimuth data and distance data calculated from the amount of wheel rotation are stored in advance in the unmanned vehicle. 2. A device for controlling the steering of an unmanned vehicle while comparing the data with data obtained by the unmanned vehicle, the device comprising: means for detecting the tilt of the unmanned vehicle every time it travels an arbitrary predetermined distance; and means for detecting a positional shift of the unmanned vehicle. 1. A driving guidance device for an unmanned vehicle, comprising: means for controlling steering to correct a traveling error of the unmanned vehicle based on outputs from two detection means.