JPH0311405A - Operation control method for automatic guided vehicle - Google Patents

Abstract

PURPOSE:To eliminate the difference of a stopping position by stopping an automatic guided vehicle approaching always from the same direction when the automatic guided vehicle provided with the idle wheel of caster construction to follow a driving wheel is stopped at some specified station. CONSTITUTION:The wheels of the automatic guided vehicle 1 are constituted of the driving wheels 2 and the idle wheels 3 of the caster construction driven as following the driving wheels. When the automatic-guided vehicle 1 approaches and stops to and at the same station 5, it is made to approach always in the same approaching direction, for instance, the approaching direction of the direc tion (right to left) shown by a continuous line. For instance, in case the approaching direction of the automatic guided vehicle to the station 5 is from the direction of a dot line B as shown by a vehicle 1' because of the condition of a route, the vehicle is controlled so that only its traveling direction is changed while a body direction is left the same after going beyond the station 5, and the vehicle approaches to the station 5 as shown by the vehicle 1, and stops at the station 5. Thus, the difference of the stopping position can be entirely eliminated.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for controlling the operation of an unmanned guided vehicle 1 equipped with a transfer device such as a robot or a conveyor. The wheels are as shown in Figure 2.
It is composed of a driving wheel 2 and a caster structure idler wheel 3 that is driven to follow the driving wheel 2.

Note that 4 is a transfer device such as a robot.

Conventionally, when an unmanned guided vehicle approaches a station and stops, it approaches in a direction determined according to a route determined between the vehicle and the previous station.

Therefore, in the conventional case, when the unmanned guided vehicle 1 approaches the same station 5 and stops, as shown by the dotted arrow in FIG. 1, in case A, it approaches from the right to the left and stops. Conversely, B approaches from left to right and stops.
There were two types of operation control in the case of .

[Problems to be Solved by the Invention] Incidentally, for example, in a clean room used in a semiconductor manufacturing process, a ventilation grating is generally provided on the floor surface.

This grating may be provided on the entire floor of the clean room, or may be provided on a part of the floor as shown in FIG.

In the case of grating 6 such as No. 2 (21), the size is, for example, about 600 x 600, but it is difficult to make the thickness of each grating uniform. There will be a difference in level from 2nd to 31st.Also,
When grating is installed on the entire floor, multiple gratings are connected together, but in this case, a gap of a few feet may be created between the joints. When the unmanned guided vehicle 1 enters and stops at one station 5, the position of the vehicle body facing the station 5 is the same regardless of the direction of approach, and the ground contact position of the driving wheels does not change. Due to its mechanism, the ground contact position with respect to the floor surface is different.

That is, when entering the same station 5 from the right direction as shown in FIG. 2 (a) and from the left direction as shown in FIG. It is normal for the position to shift.

Therefore, in the case of rightward approach, the idler wheel 3 was able to avoid the grating 6 and stop as shown in Figure 2 (a), but in the case of leftward approach, as shown in the same figure (b), A situation arises in which the train stops at the station 5 with the idler wheel 3 resting on the grating 6.

By the way, when a transfer device 4 such as a robot is mounted on this type of unmanned guided vehicle 1, handling accuracy of approximately ±llIn is generally required.

Most of these robots are of the type that brake back the taught program, and when the idler wheels 3 are placed on a part 2M higher than the floor and the body of the vehicle 1 is tilted, it is difficult to move the program with the correct accuracy based on the teaching. There was a problem that the computer could no longer be operated.

An object of the present invention is to provide a method for controlling the operation of an unmanned guided vehicle that solves these problems.

[Means for Solving the Problems] The present invention provides an unmanned guided vehicle equipped with wheels consisting of a driving wheel and m-wheels of a caster structure that follow the driving wheel, and when stopping the unmanned guided vehicle at a certain station,
The present invention relates to a method of controlling the operation of an unmanned guided vehicle that always approaches and stops from the same direction.

In the case of an unmanned guided vehicle equipped with a robot, the direction in which the vehicle stops at the station (posture when stopped) is the same as the direction (posture) of the unmanned guided vehicle when teaching is performed to the arm of the robot. Same direction (
It is desirable to have the option of selecting the correct position (posture).

[Example] The present invention will be specifically described below with reference to an example shown in FIG.

That is, in the operation control method for an unmanned guided vehicle of the present invention, the first
As shown in the figure, entering the same station 5,
When stopping, the vehicle should always approach in the same direction, for example, in direction C (right→left) shown by the solid line in FIG. As shown at 1°, if the direction of approach of the unmanned guided vehicle to station 5 is from direction B, after passing through station 5, only the direction of travel is changed while the vehicle remains in the same direction. Station 5 in direction C as shown in vehicle l
The operation of the unmanned guided vehicle is controlled so that the vehicle enters Station 5 and stops at Station 5.

In this case, for an unmanned guided vehicle equipped with a robot, the direction (orientation) of the unmanned guided vehicle when teaching is performed for the arm of the robot is defined as the stopping direction (or posture) of the vehicle at the station. It is necessary to select the same direction (posture) as the robot so that the teaching performed on the robot is not wasted.

[Effects of the Invention] In the operation control method for an unmanned guided vehicle of the present invention, when stopping two guided vehicles at a station, the approach direction to the station is controlled to be unified to a predetermined approach direction. It has the following excellent effects.

■Gratings are installed on the floor, such as in clean rooms of semiconductor manufacturing plants.

Even when there is a slight difference in level on the floor surface, the guided vehicle can be stopped at the station without the idle wheels resting on such a difference in level.

Therefore, in a guided vehicle equipped with a transfer device such as a robot, cargo handling operations are not hindered by the tilting of the vehicle body, teaching is not wasted, and accurate cargo handling operations can be performed.

■Also. In general, unmanned guided vehicles use sensors on the vehicle body to detect the stop position using a mark affixed to the floor.

In this case, it is common to be equipped with a sensor dedicated to the direction of travel.1Due to the difference in the positional relationship between these sensors, mark sensors, and the vehicle body, when stopping the unmanned guided vehicle by changing the direction of approach, the unmanned guided vehicle The stopping positions of the two will be different.

However, in the operation control method for an unmanned guided vehicle according to the present invention,
Regardless of the initial approach direction of the unmanned guided vehicle to the station, the direction of the vehicle body when stopped is controlled so that it always approaches in the same direction, so there is no possibility that the stopping position will be different.

[Brief explanation of drawings]

10 is a front view illustrating the travel control of the guided vehicle to the station in the conventional system and the present invention; FIG. Further, FIGS. 2(a) and 2(b) are front views for explaining problems in the conventional travel control, respectively. 1: Guided vehicle 2; Driving wheel/idling wheel transfer device station grating: Approach direction of the present invention Fig. 1

Claims (1)

[Claims] (1) In an unmanned guided vehicle equipped with wheels consisting of a driving wheel and a idler wheel with a caster structure that follows the driving wheel, when the unmanned guided vehicle is stopped at a specific station, it must be approached from the same direction and stopped. A method for controlling the operation of an unmanned guided vehicle. (2) In the case of an unmanned guided vehicle equipped with a robot, select the same direction as the direction of the unmanned guided vehicle when teaching the arm of the robot as the stopping direction of the vehicle at the station. The operation control method for an unmanned guided vehicle according to claim 1.