JPH061240A - Method of preventing automated guided vehicle mutual collision at confluence and device therefor - Google Patents

Abstract

PURPOSE:To prevent the mutual collision of automated guided vehicles at a confluence positively with out constraining the disposition of routes and without being attended by difficult adjustment. CONSTITUTION:Stop points are provided in front of the confluence 12 of routes 1, 2, and stop point marks 3, 4 are stuck onto the travel paths so that automated guided vehicles are once stopped. An automated guided vehicle 9 or 10 stopped earlier at the stop point is let pass the confluence by commanding start from a control box 5 or 6. At the same time, the route is closed during the confluence passing time of the automated guided vehicle 9 or 10, and this is communicated from the control box 5 or 6 to the control box 6 or 5 through a control box communication line 11. Receiving this, the control box 6 or 5 makes the automated guided vehicle 10 or 9, stopped at the stop point later, stand by at the stop point during the closure of the route.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for preventing an automatic guided vehicle used in a factory or the like from colliding with each other at a merging point so that the automatic guided vehicle can safely travel at the merging point without collision. is there.

[0002]

2. Description of the Related Art FIG. 5 shows an example of an automated guided vehicle system together with a layout of a factory production line. In the figure,
101 is a manufacturing line, 102 is an automated guided vehicle route, 1
Reference numeral 03 is a loading station, 104 is a line station, 105 is a home station, 106 is a cross junction, and 107 is a Y-shaped junction.

A guide line or the like is laid on the route 101. Automated guided vehicle (AGV: automatic
Guided vehicle) runs in the direction of the arrow guided by it, from loading station 103 to line station 104 or line station 104.
Transports materials, parts or semi-finished products from the other to the other line station 104. The unmanned guided vehicle that has finished carrying travels to the home station 105, and waits until the next carrying instruction is given.

Here, there are confluence points 106 and 107 on the route 102 where the automatic guided vehicles enter from two directions. When an automated guided vehicle enters the merging points 106 and 107 almost at the same time, a collision occurs. Therefore, conventionally, each automated guided vehicle is provided with an obstacle sensor or an approach sensor of an automated guided vehicle mutual communication system using radio waves to collide. Was prevented.

[0005]

However, among the methods for preventing the collision of the guided vehicles with each other at the confluence point according to the above-mentioned conventional technique, the method of attaching the obstacle sensor to the guided vehicle does not detect each other and cannot move. Therefore, it is difficult to adjust the sensor sensitivity, the sensing range, and the like, and there is a problem that they are restricted. Especially when joining at right angles, there is a risk that collision cannot be prevented,
There was a problem that constrained the layout of routes.

On the other hand, in the collision prevention method using the automatic guided vehicle mutual communication method using radio waves, there is a problem in that the structure of the devices relating to them is complicated and the price is high, and it is difficult to adjust the output of radio waves and the reception sensitivity in the same manner as above. In addition, since radio waves are used, it has been pointed out that there is a risk of adversely affecting other devices.

The present invention has been made in order to solve these problems, and its purpose is not to restrict the arrangement of the route, to make difficult adjustment unnecessary, and to prevent the collision surely. An object of the present invention is to provide a method and an apparatus for preventing collision between unmanned guided vehicles at a confluent point.

[0008]

In order to achieve the above-mentioned object, in the method for preventing the collision of the guided vehicles with each other at the confluence of the present invention, the unmanned conveyance of the own route side before the confluence of a plurality of routes. Stopping the vehicle, detecting the stop of the automatic guided vehicle of the own route and notifying the other route, and determining whether or not another automatic guided vehicle is stopped on the other route and / or the route Check whether the vehicle is open or closed, and if it is confirmed that another automated guided vehicle is not stopped on the other route and / or the route is opened The step of notifying the other route side of the blockage of the route between the time when the automated guided vehicle is started and the time when the automated guided vehicle passes through the confluence, and the other automated guided vehicle is stopped on the other route, or and When it is confirmed that the route is blocked, the route is opened from the other route side, and then the automatic guided vehicle of the own route is started to notify the other route side of the blocked route. And are characterized by having.

Also, in the collision preventing apparatus for unmanned guided vehicles at the merging point of the present invention, means for notifying the unmanned guided vehicle of the stop position before the merging point of its own route,
A sensor for detecting the stop of the automatic guided vehicle, an optical communication means for instructing the automatic guided vehicle to start, a means for outputting the timing of closing the route from the start to the passage of the confluence, and another route side. In contrast to the automatic guided vehicle stop or /
And an inter-route communication means for notifying the timing of the closure of the route, and a stop of the automated guided vehicle of another route via the inter-route communication means when the sensor detects the stop of the automated guided vehicle, and / or A means for confirming the timing of blockage of the route, determining avoidance of a collision at the confluence, instructing the automatic guided vehicle of the own route to start the vehicle through the optical communication means, and outputting the timing of blockage of the route. The control means for starting is provided.

[0010]

According to the method and apparatus for preventing the collision between the automated guided vehicles at the merging point of the present invention, a stop point is provided in front of the merging point of each route, and an unmanned guided vehicle that stops at this stop point even a little earlier is provided. An unmanned guided vehicle that has been commanded to start and passes through the confluence point and has entered another stop point with a delay is made to wait at the stop point of the route during the timing at which the preceding automatic guided vehicle passes the confluence point. As described above, the collision of the automated guided vehicle at the merging point is reliably prevented.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a block diagram of a merging portion showing an embodiment of the present invention, and FIGS. 2 (a) and 2 (b) are external views of a control box installed in the merging portion. In the figure, 1 and 2 are two unmanned guided vehicle traveling routes (hereinafter referred to as routes) that meet at a confluence point, 3 is a stop point mark of route 1, 4 is a stop point mark of route 2, and 5 is a route 1
Side control box, 6 is a route 2 side control box, 7 is an infrared communication unit, 8 is an automated guided vehicle confirmation sensor, 9 is an automated guided vehicle on the route 1 side, 10 is an automated guided vehicle on the route 2 side, 11 is Communication line between control boxes between routes 1 and 2, 12 is two routes 1 and 2.
The Y-shaped confluence point is shown.

It is assumed that the automatic guided vehicles 9 and 10 travel in the directions of the arrows shown on the routes 1 and 2 and that a light reflection type stop point detection sensor is provided at the rear portion. The stop point mark is an example of a means for stopping the automatic guided vehicle in this embodiment, is made of a light reflecting tape, and is attached to the stop point on the traveling path corresponding to the position of the stop point detection sensor. The stop point is set before the confluence 12 of the routes 1 and 2.

The control boxes 5 and 6 receive the arrival signals from the unmanned guided vehicle confirmation sensors 8 that detect the stopped unmanned guided vehicles 9 and 10, and the unmanned guided vehicles 9 and 10 as well. It has an infrared communication unit 7 for instructing the vehicle to start. The control box 5 installed on the route 1 and the control box 6 installed on the route 2 are the communication lines between the control boxes 1
Connected by 1 (wired) and used as a set of 2 units.

The block diagram of FIG. 3 shows the internal structure of each control box. In the figure, 7 is the infrared communication unit described above, 8 is the above-mentioned automated guided vehicle confirmation sensor, 1
3 is a communication unit between control boxes, 14 is a control unit, 15 is a timer, and 16 is a clock circuit.

The control unit 14 performs input / output with each of the above units, and when the sensor 8 detects the stop of the automatic guided vehicle, the automatic guided vehicle of another control box is stopped via the inter-control box communication unit 13. And the timer output, that is, the timing of the route closing, to determine the avoidance of the collision at the merging point, and to command the unmanned guided vehicle of the own route to start via the infrared communication unit 17, and the timing of the route closing. Timer 15 that outputs
To start. In the above, the control box communication unit 13 is connected to the inter-control box communication line 11 of FIG. The clock circuit 16 is connected to the clock circuits of other control boxes via the inter-control-box communication line 11 or a dedicated line, and is synchronized with each other in the control unit 1
Among the control operations of 4, the time difference is provided at least in the timing of detecting the stop. This is an example of a means for giving priority to one of the two control boxes 5 and 6 at the same time by confirming that the unmanned guided vehicle on the other route is stopped and not entering a deadlock state. As another means of giving priority, only one control box side monitors the timer until the unmanned guided vehicle of the other route starts and the stop detection is released, and the unmanned guided vehicle of the own route is timed up. A method of starting it is also possible. In this example, priority is given to the one control box side.

The operation and action of the embodiment configured as described above will be described. FIG. 4 is an operation flow chart for explaining a method of preventing collisions between the automated guided vehicles at the confluence of this embodiment.

Unmanned guided vehicles (A from route 1)
When the GV) 9 arrives at the stop point indicated by the stop point mark 3, the control unit 14 of the control box 5 determines whether there is an automatic guided vehicle in front of the control box 6 via the inter-control box communication line 11. Check for any.

In each control box, the presence or absence of an unmanned guided vehicle is detected by the unmanned guided vehicle confirmation sensor 8, and the time until the unmanned guided vehicle passes the merging portion is set by the timer 15, and the time is set as a route. The signal indicating the presence of an automated guided vehicle is sent to notify the other of the control boxes via the inter-control-box communication line 11.

For example, when the control box 6 on the route 2 side has an automated guided vehicle, the control box 5 stops the automated guided vehicle 9 on the route 1 side until the timer 15 of the control box 6 times out. Wait at the stop point indicated by. When the control box 6 has timed out, the timed-up signal or a signal without an automated guided vehicle indicating the opening of the route is sent through the communication line 11 to the control box 5.
Let us know. In response to this, the control box 5 starts infrared communication with the automatic guided vehicle 9, receives an arrival signal from the automatic guided vehicle 9, outputs a start signal to the automatic guided vehicle 9, and starts the vehicle. Here, the control box 5 outputs a start signal and at the same time operates its own timer 15 to send a signal indicating that there is an automatic guided vehicle to the control box 6 as described above.

The timer time until the automatic guided vehicle 9 passes the merging point 12 can be set in advance. Even if the automatic guided vehicle 10 arrives at the stop point on the route 2 side indicated by the stop point mark 4 within this set time, the control box 6 does not start infrared communication with the automatic guided vehicle 10 and the unmanned automatic guided vehicle 10 does not start. The carrier 10 is put on standby at the stop point indicated by the stop point mark 4. When the timer 15 of the control box 5 times out, the control box 6 receives the arrival signal of the automatic guided vehicle 10 and outputs the start signal at the same time as the control box 6 starts its own timer 15 to close the route 1 to the closed state. To do. As described above, while the timer 15 of the control box 6 is operating, the automatic guided vehicle 9 at the stop point of the stop point mark 3 waits until the time is up.

As a result of the above operation, the unmanned guided vehicle that stopped at the stop point first travels at the confluence point, and then the unmanned guided vehicle that stops at the stop point of the other route then joins the unmanned carrier vehicle at the confluence point. Wait at that stop point until you currency. If the automated guided vehicles stop at the stop points of Route 1 and Route 2 at exactly the same time, one of them will be given priority, and the deadlock state will not occur. The automated guided vehicle will start first.

As described above, in this embodiment, while the automatic guided vehicle is passing through the junction of the route, the system is constructed so that another automatic guided vehicle cannot enter the junction, so that the collision is surely prevented. Further, in the present embodiment, no difficult adjustment such as output adjustment, sensitivity adjustment, and adjustment of the sensing range is involved, and since radio waves are not used, other devices are not adversely affected.

In the above embodiment, the merging of two routes has been described, but the merging point of three or more routes can be expanded by installing a control box in each route. It is also obvious that it can be applied not only to the Y-shaped confluence but also to the cross confluence. In addition, when the distance from the stop point to the confluence point is small and the speed of the automated guided vehicle is high, blockage / opening of the route is omitted, and self-detection is possible only by not detecting the stop of the automated guided vehicle of another route. It may be possible to avoid the collision even if the automated guided vehicle on the route is started. Further, the present device can be used to control an automated guided vehicle even at other route portions except the confluence. As described above, the present invention can be applied in various ways in accordance with the gist thereof and can take various embodiments.

[0025]

As is apparent from the above description, according to the method and apparatus for preventing the collision of the guided vehicles with each other at the merging point of the present invention, it is difficult to adjust the collision at the merging portion of the automatic guided vehicle traveling route. It can be surely prevented without causing. Further, the automatic guided vehicle body does not need a mutual collision preventing measure which is difficult to adjust or has a complicated structure.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a merging portion showing an embodiment of the present invention.

2 (a) and 2 (b) are external views of two control boxes installed in the confluence section.

FIG. 3 is a block diagram showing an internal configuration of the control box.

FIG. 4 is an operation flow chart for explaining a collision prevention method for an automated guided vehicle at a confluence point in the above embodiment.

FIG. 5 is a diagram showing a configuration example of an unmanned transportation system.

[Explanation of symbols]

 1, 2 ... Unmanned guided vehicle running route 3 ... Stop point mark on route 1 4 ... Stop point mark on route 2 5 ... Control box on route 1 side 6 ... Control box on route 2 side 7 ... Infrared communication unit 8 ... Unmanned transport Vehicle confirmation sensor 9 ... Automatic guided vehicle on route 1 side 10 ... Automated guided vehicle on route 2 side 11 ... Communication line between control boxes 12 ... Merging point 13 ... Communication unit between control boxes 14 ... Control section 15 ... Timer 16 ... Clock circuit

Claims (4)

[Claims] 1. A step of stopping an automated guided vehicle of its own route before the confluence of a plurality of routes, and a step of detecting the stop of the automated guided vehicle of its own route and notifying the other route side. Confirming whether another automated guided vehicle is stopped on the other route and / or whether the route is open or closed; and another automated guided vehicle is stopped on the other route. When it is confirmed that there is no route and / or the route is open, the unmanned guided vehicle of the own route is started and the blockage of the route is notified to the other route side before the vehicle passes the junction. And when it is confirmed that the other automated guided vehicle is stopped or / and the route is blocked on the other route, the route is released from the other route side, and root AGV mutual method of collision avoidance in converging, characterized in that it comprises the steps of notifying an occlusion of the root to the other route side by starting the automatic guided vehicle, a. 2. The method for preventing collision between unmanned guided vehicles at a junction according to claim 1, wherein priority is given to detection of stop of the guided vehicles on a plurality of routes. 3. A means for notifying an automatic guided vehicle of a stop position just before the confluence of its own route, a sensor for detecting the stop of the automatic guided vehicle, and an optical communication means for instructing the automatic guided vehicle to start. Means for outputting timing of blockage of a route from the start to passage of the confluence; inter-route communication means for notifying other route side of timing of stop of the automatic guided vehicle and / or blockage of the route, When the sensor detects the stop of the automatic guided vehicle, the timing of stopping or / and closing the route of the automatic guided vehicle of another route is confirmed through the inter-route communication means to avoid the collision at the confluence. And a control means for deciding and instructing the automatic guided vehicle of its own route to start the vehicle through the optical communication means and activating means for outputting the timing of blockage of the route. AGV mutual collision prevention device in converging, characterized by Bei. 4. The collision between the automatic guided vehicles at the confluence of claim 3, wherein the sensor or the control means includes means for giving priority to the routes when detecting the stop of the automatic guided vehicles. Prevention device.