JPH03188512A - Obstacle detector for unattended carriage - Google Patents

Abstract

PURPOSE:To surely detect an obstacle on a running route even at the time of turning by shaking detecting sensors toward an advance target direction based on signals from difference detecting sensors in the case of the difference between the axle direction of an unattended carriage and the advance target direction. CONSTITUTION:When an unattended carriage 15 enters to a curved running course to cause the difference between the axel direction of the unattended carriage 15 and the advance target direction, the unattended carriage 15 is so turned that the axel direction coincides with the advance target direction. Meanwhile, difference detecting sensors 20 and 21 detect the difference between the axel direction and the advance target direction to send signals to a shaking means 36, and then, the shaking means 36 shakes detecting sensors 26 and 27 toward the advance target direction. Thus, obstacles on the running course which the unattended carriage 15 will run on are surely detected by detecting sensors 26 and 27 though the unattended carriage 15 is turned, and the unattended carriage is surely prevented from colliding with obstacles.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an obstacle detection device that detects obstacles that obstruct the travel of an automatic guided vehicle.

Conventionally, the automatic guided vehicle 1 is operated unmanned, so the third
As shown in the figure, the front of the vehicle in the axle direction is constantly detected by at least one, usually two, obstacle detection sensor 2 fixed to the automatic guided vehicle 1, and the presence of an obstacle 4 on the travel path of the automatic guided vehicle 1. In such a case, the automatic guided vehicle 1 is stopped from running based on the detection signal from the detection sensor 2.

However, such a detection sensor 2 is
Therefore, even when the automatic guided vehicle 1 is turning or, for example, in the middle of turning left as shown in FIG. However, it is not possible to detect the diagonally forward left direction where the automatic guided vehicle 1 is about to travel. As a result, even if an obstacle 5 exists on the travel route, the automatic guided vehicle 1
The vehicle continues to run and collides with the obstacle 5.

An object of the present invention is to provide an obstacle detection device for an automatic guided vehicle that can reliably detect obstacles on a traveling route both when traveling straight and when turning.

These purposes include a difference detection sensor that is attached to an automatic guided vehicle to detect the difference between the axle direction of the automatic guided vehicle and the target direction of travel, and a difference detection sensor that is attached to the automatic guided vehicle so that it can swing in the horizontal direction. A detection sensor that detects obstacles in front of the vehicle.

Achieved by including a swing means for swinging the detection sensor toward the target direction of travel based on a signal from the difference detection sensor when there is a difference between the axle direction of the automatic guided vehicle and the target direction of travel. can do.

Assume that the automatic guided vehicle is now traveling along a straight travel route. At this time, since the axle direction of the automatic guided vehicle is the same as the traveling target direction, the swinging means does not operate, and the detection sensor detects the presence or absence of an obstacle in front of the automatic guided vehicle in the axle direction.

Next, when the S person guided vehicle approaches a curved travel route and there is a discrepancy between the axle direction of the automated guided vehicle and the target traveling direction, the automated guided vehicle turns so that the axle direction matches the targeted traveling direction. . On the other hand, the difference detection sensor detects the difference between the axle direction and the target traveling direction and sends a signal to the swinging means, so the swinging means swings the detection sensor toward the target traveling direction. When the detection sensor swings in the direction of the target traveling direction in this manner, the detection area by the detection sensor shifts toward the future travel route of the automatic guided vehicle. As a result, even when the automatic guided vehicle is turning, obstacles on the future travel path of the automatic guided vehicle are reliably detected by the detection sensor, and collisions with obstacles are reliably prevented.

1 difference 1 Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1.2, reference numeral 11 denotes a traveling guide, such as a reflective tape, stuck on a floor surface 12, and this traveling guide 11 is laid along a predetermined traveling locus of the automatic guided vehicle 15. Automated guided vehicle! 5 has a frame 18, and the front part of this frame 1B has a steering shaft 1 extending vertically.
7 is rotatably supported. A steering wheel 18 that moves on the floor surface 12 is rotatably supported at the lower end of the steering shaft 17, and a plurality of rear wheels (not shown) that move on the floor surface 12 are supported at the rear of the frame H1. Rotatably supported. The rear wheels are driven and rotated by a motor 18 attached to the frame 1B, thereby allowing the automatic guided vehicle 15 to travel forward and backward. 20.
Reference numeral 21 denotes a pair of difference detection sensors, such as photoelectric sensors, attached to the steering shaft 17 via a bracket 22, and these difference detection sensors 20 and 21 are connected to a light source (not shown) attached to the lower part of the steering shaft 17. The traveling guide 11 receives the reflected light of the light irradiated to the traveling guide 11 from the
1 and the steering wheel 18, that is, when there is a difference between the axle direction G of the automatic guided vehicle 15 and the target traveling direction S, this is detected and a detection signal is generated. Output. Here, the axle direction G of the automatic guided vehicle 15 is the extending direction of a straight line passing through the center of the automatic guided vehicle i5 in the width direction, and the target traveling direction S of the automatic guided vehicle 15 is the direction in which the automatic guided vehicle 15 extends. is the direction in which we will proceed from now on. A bracket 25 attached to the upper end of the steering shaft 17 has a pair of detection sensors 2B, 2? For example, a reflective photoelectric sensor is attached, and when the automatic guided vehicle 15 is moving forward with the steering wheel 18 facing forward in the axle direction G, each detection sensor 2B, 27 faces forward in the axle direction G, that is, in the forward direction. An obstacle 28 in front of the automatic guided vehicle 15 is detected. As described above, these detection sensors 2B and 27 are attached to the steering shaft 17 that rotates around the vertical axis, so that they are attached to the automatic guided vehicle 15 so that they can be rotated in the horizontal direction. 31 is a motor attached to the front part of the frame 1B, and a belt 35 is hung between a pulley 33 fixed to the output shaft 32 of this motor 31 and a pulley 34 fixed to the lower part of the steering shaft 17. has been passed. The motor 31 is connected to the difference detection sensor 20.
When a detection signal from 21 is input, the motor 31 rotates by an amount corresponding to the detection signal, thereby rotating the steering shaft 17.
．． The steering wheel 18 and the detection sensors 2B and 27 are moving in the target direction S.
Turn horizontally towards the side. The aforementioned motor 31
, the pulleys 33, 34, and the belt 35 as a whole are detected by the detection sensor 2 based on the signals from the difference detection sensors 20, 21.
A swinging means 3B is configured to swing the steering wheel B, 27 toward the target traveling direction S by a predetermined amount, here by the same amount as the turning amount of the steering shaft 17.

Next, the operation of one embodiment of the present invention will be explained.

Suppose now that the automatic guided vehicle 15 is moving forward along the traveling guide 11 that extends linearly. At this time, automatic guided vehicle 15
Since the axle direction G and the target traveling direction S are the same, the swinging means 3B does not operate, and as a result, the detection sensor 2B,
27 faces forward in the axle direction G to detect obstacles in front of which the automatic guided vehicle 15 will be traveling. If an obstacle 28 exists on the traveling route ahead of the automatic guided vehicle 15, this obstacle 2B is detected by the detection sensors 2B and 27, and the traveling of the automatic guided vehicle 15 is stopped.

Next, when the automatic guided vehicle 15 approaches a curved portion of the travel guide 11, in this embodiment, a curved portion to the left, a discrepancy occurs between the axle direction G of the automatic guided vehicle 15 and the target traveling direction S. , and the traveling guide 11 detects the difference detection sensor 20.
As the light source moves away from the object and approaches the difference detection sensor 21, the amount of light received by both the difference detection sensors 20 and 21 changes. As a result, the difference detection sensor 20.21 detects that a difference has occurred between the axle direction G of the automatic guided vehicle 15 and the target traveling direction S, outputs a detection signal to the motor 31, and operates the motor 31. The steering shaft 17 and the steering wheel 18 are rotated to the left around the vertical axis, and the automatic guided vehicle 15 is moved in the target traveling direction S so that the axle direction G and the target traveling direction S match.
side, here turn it to the left. At this time, since the detection sensors 26 and 27 are attached to the steering shaft 17, the swinging means 3B operates based on the detection signal from the difference detection sensor 20. is swung toward the target traveling direction S of the automatic guided vehicle 15, here to the left. When the detection sensors 28 and 27 swing in the direction S toward the target direction of movement, these detection sensors 28 and 27
．． 27 is shifted toward the future travel route of the automatic guided vehicle 15. As a result, the detection sensors 26 and 27 detect the future travel route of the automatic guided vehicle 15, even if an obstacle 37 exists on the curved travel route as shown in FIG. This obstacle 37 can be reliably detected, and a situation in which the automatic guided vehicle 15 collides with the obstacle 37 when turning can be reliably prevented.

In addition, in the above-mentioned embodiment, the difference detection sensor 20.
21 detects the lateral deviation between the travel guide 11 and the automatic guided vehicle 15, thereby detecting the difference between the axle direction G of the automatic guided vehicle 15 and the target traveling direction S. , steering shaft 17 or steering wheel 1
The difference between the axle direction G of the automatic guided vehicle 15 and the target traveling direction S may be detected by detecting the rotation of the automatic guided vehicle 8 around the vertical axis. The detection sensors 28, 27 are attached to the steering shaft 17, and the detection sensors 2B, 27 are oscillated by rotating the steering shaft 17 by the oscillating means 36, but in this invention, the detection sensors 2B, 27 are 27 may be rotatably supported by the frame IB separately from the steering shaft 17, and the detection sensors 2B and 27 may be oscillated by an oscillating means consisting of a motor, cylinder, etc. separate from the motor 31. Furthermore, in the above embodiment, a reflective tape was used as the travel guide and a photoelectric sensor was used as the detection sensor, but in this invention, a tow bus wire through which a low frequency current flows is used as the travel guide, and a tow bus wire is used as the difference detection sensor. A pickup coil that detects electromagnetic waves from the sensor may be used.

Brother JLL! L button As explained above, according to the present invention, obstacles on the travel route can be reliably detected both when traveling straight and when turning.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of the present invention, Fig. 2 is a schematic plan view showing how detection is performed when running, and Fig. 3 is a diagram showing how a conventional obstacle detection device detects when running. FIG. 15...Automated guided vehicle 20, 21...Difference detection sensor

Claims (1)

[Claims] A difference detection sensor is attached to the automatic guided vehicle and detects the difference between the axle direction of the automatic guided vehicle and the target direction of movement, and a difference detection sensor is attached to the automatic guided vehicle so that it can swing in the horizontal direction, and detects obstacles in front of the automatic guided vehicle. a detection sensor that detects the direction of the automatic guided vehicle, and a swinging device that swings the detection sensor toward the target direction of travel based on a signal from the difference detection sensor when there is a difference between the axle direction of the automatic guided vehicle and the target direction of travel. An obstacle detection device for an unmanned guided vehicle, comprising: