JP3300477B2 - Compensation data communication method between robots - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inter-robot correction data communication system in a robot system in which a plurality of robots having a common coordinate system work on one work.

[0002]

2. Description of the Related Art In a robot system in which a plurality of robots work on one work, it is important that each robot accurately recognizes the position of the work in order to perform the work accurately. . For this reason, each robot is provided with a detection device such as a laser sensor for detecting the position of the work, and each robot determines an accurate position of the work using correction data obtained based on the detection signal. I was trying to recognize.

[0003]

However, in the above-mentioned conventional robot system, since a detecting device is provided for each robot, the cost is increased accordingly.

Therefore, it is possible to attach the detection device to only one robot and connect the detection device to other robots to share the detection signal. In addition, since each robot requires an analog signal and a converter for converting the signal into a digital signal, the effect of using a single detection device cannot be sufficiently improved.

In this case, if the detecting device has a brain such as an image processing device, the device itself can process the detection signal to obtain correction data and notify the robot of the correction data. With such a detection device having no brain, it is not possible to obtain correction data by itself and notify each robot.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and in a robot system, an inter-robot correction data communication system that allows only one robot to have a detection device for detecting a work position shift. The purpose is to provide.

[0007]

According to the present invention, in order to solve the above-mentioned problems, a plurality of robots having a common coordinate system are provided.
In the inter-robot correction data communication method in a robot system that performs an operation on one work, a position shift detecting means provided on one of the plurality of robots for detecting a position shift of the work; Correction data calculating means for obtaining correction data between the position of the work at the time of teaching and the position of the work at the time of teaching based on the data from the displacement detecting means, and correction data transmission for transmitting the correction data to another robot Means, and a correction data receiving means provided on the other robot side for receiving the correction data.

[0008]

The displacement detecting means for detecting the displacement of the work is provided only for one of the plurality of robots. The correction data calculation means receives the data from the displacement detection means and obtains correction data between the position of the work at the time of teaching and the position of the work at the time of work. The correction data transmitting means transmits the correction data to each of the other robots. A correction data receiving means is provided on each of the other robots and receives the transmitted correction data. Each robot recognizes the actual position of the work using the received correction data, and approaches the work accurately based on the recognized position.

[0009]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an entire configuration of a correction data communication method between robots of the present invention. In the figure, robot 1,
2, 3, and 4 constitute a robot system as a whole with a common coordinate system, and work on the work 5 in cooperation with each other.

The work 5 is carried, for example, by a belt conveyor (not shown) and set at a predetermined position. Although the original setting position of the work 5 is taught in advance to the robots 1 to 4, when the work 5 moves and the next work is set, there is a slight deviation from the taught position. A laser sensor 1b is provided at the tip of the arm 1a of the robot 1 to detect the deviation.

The laser sensor 1 b detects a screw hole 5 a specified specifically for detection in the work 5, and sends a detection signal to the robot controller 10. The correction data calculation means 11 of the robot control device 10 receives the detection signal, obtains correction data ΔD between the teaching position of the work 5 and the current actual position, and sends the correction data ΔD to the correction data transmission means 12. . The correction data transmitting means 12 transmits the correction data ΔD to the robot controllers 20, 30, and 40 of the other robots 2, 3, and 4, respectively. The transmission is performed using, for example, an RS232C communication cable. The robot controller 10 itself calculates the correction data ΔD
Is used to accurately recognize the current actual position of the work 5.

On the other hand, each of the robot controllers 20, 30, and 40 of the robots 2, 3, and 4 has a robot controller 10
Is received by the correction data receiving means 22, 32, and 42, and the actual actual position of the work 5 is recognized using the received correction data ΔD, similarly to the robot controller 10. I do. Each of the robots 1 to 4 causes the tip of each of the arms 1 a to 4 a to approach the work 5 based on the recognized actual position of the work 5. Thereby, the work on the work 5 as the robot system is performed.

As described above, the laser sensor 1b is provided only in one robot 1, the correction data ΔD relating to the position of the work 5 is obtained based on the detection signal of the laser sensor 1b, and the correction data ΔD Robot 2,
Communicate to 3,4. Therefore, only one laser sensor conventionally provided in each robot can be used, and the cost can be significantly reduced.

Further, by using one laser sensor,
The failure rate of the laser sensor is also greatly reduced, and the reliability is improved. Further, since there is no detection error generated between the laser sensors, the operation of each robot as a robot system becomes tighter.

FIG. 2 is a schematic block diagram of the robot control device 10. In the figure, a processor 101 of a robot controller 10 controls the entire robot controller 10 according to a system program stored in a ROM 102. The RAM 103 stores various data. The nonvolatile memory 104 stores an operation program of the robot 1 and a correction data communication program according to the present invention. These processor 101, ROM 102, RA
The M103 and the non-volatile memory 104 are coupled to a bus 110 together with a teaching operation panel 105, a digital I / O 106, RS232C ports 107 and 108, an axis control circuit 111, and the like, which will be described later.

The teaching operation panel 105 is used when teaching work on the work 5 to the robot 1. The digital I / O 106 converts an analog signal sent from the laser sensor 1b into a digital signal, and
Send to one side. The processor 101 obtains the correction data ΔD based on the digital signal converted from the laser sensor 1b, stores the correction data ΔD in the nonvolatile memory 104, and stores the correction data ΔD in the RS232C port 10.
The data is sent from 7, 108 or the like to another robot control device 20 or the like.
Other robot control devices 20 and the like have an RS232C port similarly to the robot control device 10, and correction data ΔD is input to the RS232C port.

The axis control circuit 111 is provided with a servo motor 121, 122, 123, 124, 125 and 1 via a servo amplifier 112 in response to a command from the processor 101.
26 is output. These servo motors 121 and the like are built in each axis of the robot 1 and drive the robot 1 as a whole.

FIG. 3 is a flowchart showing the processing procedure of the present invention. In the figure, a numerical value following S indicates a step number. [S1] The analog signal of the laser sensor is converted into a digital signal and taken into a register in the nonvolatile memory. [S2] The correction data ΔD is calculated. [S3] The correction data ΔD is transmitted. [S4] The flag 1 is set in a register in the non-volatile memory of the transmission partner.

On the side receiving the correction data ΔD, after confirming that the flag 1 is set, the correction data ΔD
The current actual position of the work is obtained using D. In the above description, the correction data ΔD is transmitted from one robot control device to another robot control device. However, the robot control device that receives the correction data ΔD transmits the correction data ΔD to another robot control device. It can also be configured. In that case, a plurality of RS232s in the robot controller
At least one of the C ports is used for transmitting the correction data ΔD, and the other RS232C port is used for receiving. With this configuration, the correction data ΔD can be transmitted while covering a larger number of robots in the robot system.

[0020]

As described above, according to the present invention, only one robot is provided with a displacement detecting means, and correction data relating to the position of the work is obtained based on the detection signal of the displacement detecting means. The correction data is communicated to another robot.

Therefore, it is possible to use only one displacement detection means conventionally provided in each robot,
The cost can be significantly reduced accordingly. In addition, by using only one displacement detection unit, the failure rate of the displacement detection unit is greatly reduced, and the reliability is improved.

Further, since there is no detection error generated between the plurality of displacement detecting means, the operation of each robot as a robot system becomes more precise.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a correction data communication method between robots of the present invention.

FIG. 2 is a schematic block diagram of the robot control device 10.

FIG. 3 is a flowchart showing a processing procedure of the present invention.

[Explanation of symbols]

 1, 2, 3, 4 Robot 1b Laser sensor 5 Work 5a Screw hole 10, 20, 30, 40 Robot controller 11 Correction data calculation means 12 Correction data transmission means 22, 32, 42 Correction data reception means 101 Processor 104 Non-volatile Memory 106 Digital I / O 107, 108 RS232C port 111 Axis control circuit 112 Servo amplifier 121-126 Servo motor

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B25J 13/00 B25J 19/00

Claims (3)

(57) [Claims] A plurality of robots having a common coordinate system
In the inter-robot correction data communication method in a robot system that performs an operation on one work, a position shift detecting means provided on one of the plurality of robots for detecting a position shift of the work; Correction data calculating means for obtaining correction data between the position of the work at the time of teaching and the position of the work at the time of teaching based on the data from the displacement detecting means, and correction data transmission for transmitting the correction data to another robot And a correction data receiving means provided on the other robot side for receiving the correction data. 2. The correction data communication system between robots according to claim 1, wherein the correction data transmission means is also provided on the other robot side. 3. The method according to claim 1, wherein the transmission and reception of the correction data between the robots is performed using a communication line.