JPH0985654A - Synchronization control method for multiple robots - Google Patents

Abstract

(57) [Abstract] [Purpose] An object of the present invention is to provide a device that can shorten the distance between the unloader robot and the loader robot and shorten the takt time. [Configuration] An unsynchronized robot that is a master and a synchronized robot that is a slave for the unsynchronized robot are set,
The operation position of the non-synchronized robot is taught, and its reproducing operation is performed for each predetermined number of output pulses from the rotation detector attached to the drive motor of one of the drive axes of the non-synchronized robot. Teaching the operating position of the synchronized robot in correspondence with the reproduction position for each predetermined output pulse number, and instructing the operated position of the synchronized robot taught in correspondence with the output pulse number of the non-synchronized robot. Causes the synchronized robot to follow the non-synchronized robot.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tuning control method for a plurality of robots, and for example, relates to a control method for synchronizing a unloader robot and a loader robot in a system for handling a work by a plurality of robots.

[0002]

2. Description of the Related Art FIG. 6 shows an example of a handling system. In the figure, robots 1 to 3 are work stations ST1 to ST1.
A system installed during ST4 for performing work work and handling is shown. That is, the work station ST
The work in 1 is a system in which some work is performed at each station and the robot 1 to 3 reach the work station ST4 by hand link. Explaining the work station ST2, the work after the work is carried out by the robot 2 (unloader robot), and then a new unprocessed work is carried in by the robot 1 (loader robot). Explaining the work station ST3, the work after the work is carried out by the robot 3 (unloader robot), and then a new unprocessed work is carried in by the robot 2 (loader robot). The loader robot and the unloader robot are relative to each other, and can be a loader robot or an unloader robot by a single operation.

In such a system, conventionally, as shown in FIG. 5, in the control unit of the unloader robot,
The unloader robot checks the interference to see if it is within the fixed interference area, and when it escapes from the area, it issues an interlock release signal to the loader robot so that the loader robot can enter the station or the unloader robot. A timer was set in synchronization with the robot so that the loader robot could enter the station after a certain time.

[0004]

Therefore, from a safety point of view, the distance between the unloader robot and the loader robot cannot be shortened or a waiting time longer than necessary is required, resulting in an excessive takt time. There was a drawback. On the other hand, the applicant has proposed a technique disclosed in Japanese Patent Laid-Open No. 7-1060 as a robot system synchronized with a press machine. However, the encoder device attached to the press (press position detector)
However, it is not applicable to a system that does not have such a machine and is composed of only a robot.
Therefore, an object of the present invention is to provide an apparatus capable of shortening the distance between the unloader robot and the loader robot and shortening the takt time.

[0004]

According to the present invention, in a tuning control method for a plurality of robots, a pair of a non-tuned robot that is a master and a synchronized robot that is a slave to the non-tuned robot is set, and Teaching the operation of the non-synchronized robot, and the reproduction operation of the non-synchronized robot is performed every predetermined number of output pulses from the rotation detector attached to the drive motor of one of the drive axes of the non-synchronized robot. The operating position of the tuning robot is taught and stored in correspondence with the reproduction position for each predetermined output pulse number, and during actual work, the tuning that has been taught corresponding to the output pulse number is performed. It is characterized in that the synchronized robot is caused to follow the non-synchronized robot by instructing an operation position of the robot.

[0005]

The rotation detector attached to the drive motor for one of the drive shafts of the non-tuned robot is
The point of the present invention is that the robot originally has it, and the signal of this detector is used for the command of the other robot. That is, the robot on the non-tuned side, while confirming the actual operation of the robot at predetermined pulse intervals,
Teach the robot on the tuning side so that it does not interfere with the robot on the non-tuning side. Then, by synchronizing with the output pulse of the rotation detector attached to the drive motor of any one of the drive shafts of the robot on the non-tuning side, a position command is issued to the tuning side robot at predetermined intervals to perform tuning. (Follow-up) control.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention is shown in FIG.
The case of applying to the system will be described as an example. In the present invention, attention is paid to the drive shaft that moves the most in actual work. In the example of FIG. 6, it is the first axis that moves the most (it must be rotated 180 ° to convey the work). Therefore, FIG. 2A shows the number of output pulses of the rotation detector of the first axis of the unloader robot (non-tuned robot, master side) and the distance between the loader robot (tuned robot, slave side). . FIG. 2B shows the positional relationship. If the unloader robot can be transported only by rotating the first axis, it will have a sinusoidal curve like the dotted line in Fig. 2 (A), but in reality there are obstacles, etc. Figure 2
It often becomes a curve like the solid line in (A). In the present invention, first, the entire operation path is taught by teaching several operation points for the operation position of the unloader robot.
Then, the number of output pulses of the rotation detector of the first axis is divided and stored at an appropriate pulse number interval as shown in FIG. That is, it is stored as a polygonal line approximation.

Then, the movement is stopped at each pulse number interval, and the playback operation of the unloader robot is performed. The position of the unloader robot is taught to the position of the unloader robot for each pulse number interval. In consideration of the position of the unloader robot moving in the direction of removing the work from the work station, the operator judges how far the arm of the loader robot should move toward the work station and teaches. From the above, the position to which the loader robot should move is determined according to the number of output pulses of the rotation detector of the first axis of the unloader robot. That is, a correspondence table such as position P1 at the first 400th pulse, position P2 at the 700th pulse, position P3 at the 1200th pulse, etc. can be created (FIG. 4).
reference). The dotted line portion in FIG. 4 is added to explain the relationship with FIG.

If the number of output pulses of the rotation detector of the first axis of the unloader robot and the position to which the loader robot should move can be determined, if the number of output pulses of the rotation detector of the first axis of the unloader robot reaches a predetermined number. By instructing the loader robot to move to the corresponding teaching position, the loader robot can operate without interfering with the unloader robot.
Therefore, in order to realize this, the loader robot control device is instructed to receive a pulse from the first axis of the unloader robot and, when the pulse reaches a predetermined integrated amount, give a command to operate to a corresponding position in advance. Means for emitting may be added.

In order to carry out this, the correspondence table is stored in a memory in the loader robot controller. The block diagram is shown in FIG. The output pulse of the rotation detector of the first axis of the robot 3 is input to the controller 2C of the robot 2, the corresponding teaching position is output from the correspondence table to the operation command unit, and the robot 2 operates. First of the robot 2
The output pulse of the axis rotation detector is the control device 1 of the robot 1.
It is input to C, the corresponding teaching position is output from the correspondence table to the operation command unit, and the robot 1 operates. In this way, it operates in a chain reaction system. The loader robot starts to move after the number of output pulses of the rotation detector of the first axis of the unloader robot reaches a predetermined number. Become. However, if the robot is driven at high speed, it follows the robot with a slight delay, and it can be realized to the extent that it is safe to say that all robots are operating in synchronization in the handling work.

[0009]

As described above, according to the present invention, the operation of not interfering with each other at each point position is taught in advance, and the follow-up control is performed by using the output pulse of any one axis of the master robot. As a result, since it is possible to control the synchronization of a plurality of robots that are very interlaced, the tact time can be greatly shortened. Also, since very complicated movements can be synchronized, the robots can be installed at short intervals, which contributes to space saving. Furthermore, the case of tuning three or more units is basically the same as the case of two units, and it is possible to cooperate as many times as necessary, and there is also an effect that it is possible to easily cope with an increase or decrease in equipment.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a diagram illustrating the operation of the present invention.

FIG. 3 is an operation explanatory diagram of the present invention.

FIG. 4 is a diagram showing a correspondence table of the present invention.

FIG. 5 is a diagram showing a conventional example.

FIG. 6 is a diagram showing a configuration example of a handling system.

[Explanation of symbols]

 1, 2, 3 ... Robots ST1, ST2, ST3 ... Work stations 1C, 2C, 3C ... Robot controller

Claims (3)

[Claims] 1. A method for controlling synchronization of a plurality of robots, wherein a pair of a non-synchronized robot that is a master and a synchronized robot that is a slave to the non-synchronized robot is set, and the operation of the non-synchronized robot is taught. , A reproduction operation of the non-synchronized robot is performed every predetermined number of output pulses from a rotation detector attached to a drive motor of one of the drive axes of the non-synchronized robot, and the predetermined output pulse The operating position of the synchronized robot is taught and stored in correspondence with the reproduction position for each number, and during the actual work, the operated position of the synchronized robot that is taught according to the output pulse number is commanded. A tuning control method for a plurality of robots, characterized in that the tuning robot is caused to follow the non-tuning robot according to. 2. The tuning of a plurality of robots according to claim 1, wherein any one of the drive axes of the non-synchronized robot is a drive axis having the largest movement amount in the teaching target work. Control method. 3. The plurality of robots according to claim 1 or 2, wherein at least one robot is a group of three or more robots having both tuning and untuning and having a chain relationship of tuning / untuning in a shogi manner. Robot synchronization control method.