JPH01295778A - Robot system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a robot system that controls the movement of a moving part such as an arm of a robot according to an acceleration/deceleration mode.

(Prior Art) FIG. 4 is an explanatory diagram showing an outline of the overall configuration of an example of a conventional robot system.

In FIG. 4, (1) is a control unit of the robot, and the control unit (1) includes a CPU (2), a ROM (3) in which a program for controlling the robot is stored, and a ROM (3) for storing data. RAM (4), peripherals, devices and the control unit (
1) Interface with (hereinafter abbreviated as I/F)
(5) and a servo I/F (6) for outputting control signals to the robot.

In addition, peripheral devices include a teaching box (7) for operating the robot, and a CR for displaying data, etc.
T (8) and a keyboard for inputting data, etc.
9), etc., each with the above interface (5)
It is connected to the.

Furthermore, the servo I/F (6) includes a control section (1).
) for amplifying the control signal output from the amplifier (l
The robot body (11) is connected via O),
The robot body (11) has an arm (lla) which is a moving part.
).

In the robot system having the basic configuration explained above, the speed control of the moving operation of the arm (lla) is as follows.
This can be done based on a flowchart as shown in FIG. This flowchart is for a case where the speed control of arm movement is performed according to the trapezoidal acceleration/deceleration mode.

The specific control based on the above flowchart is first performed by (12
) In the trapezoidal acceleration process, a speed command value is created according to the trapezoidal acceleration/deceleration mode, and then the speed command value is output to the servo 17F by the servo I/F output in (13). After the above speed command value is output, (
In step 14), it is determined whether or not the movement of the arm (lla) has been completed, and if it has been completed, it is finished, and if it is determined that it has not been completed, it is returned to the trapezoidal acceleration process in step (12). , as mentioned above.

The theory is done again.

By the way, the arm (lla
In a conventional robot system that performs a movement operation of (), speed control of arm movement is performed according to an acceleration/deceleration mode consisting of one type of acceleration (trapezoidal acceleration/deceleration mode in FIG. 5). Therefore, the output waveform input to the robot body (11) for driving the arm (lla) will be the same when the moving distance of the arm (11a) is long as shown in FIG. 6, and when it is short as shown in FIG. Both had trapezoidal shapes with the same slope of the sides.

(Problem H to be solved by the invention) However, as described above, the arm (lla)
Controlling the movement of the robot did not amount to proper control.

In particular, since the acceleration in the acceleration/deceleration mode is normally adjusted to long-distance movement of the arm (lla), it is not necessarily appropriate for short-distance movement. In other words, even if it is possible to control the performance of a robot according to an acceleration/deceleration mode with a larger acceleration for short-distance movement, it follows an acceleration/deceleration mode with a small acceleration (trapezoidal acceleration/deceleration mode) for long-distance movement. For,
Time required for B movement of arm (lla) (takt time)
The problem was that it was longer than necessary.

The present invention has been made to solve the above-mentioned problems, and it is possible to control the moving operation of the moving part of the robot according to an appropriate acceleration/deceleration mode according to the length of the distance, and as a result, It is an object of the present invention to provide a robot system that can shorten the takt time of the operating section.

(Means for Solving the i! Problem) The robot system of the present invention is equipped with multiple types of acceleration/deceleration modes for controlling the movement of the moving parts of the robot. This allows you to select the mode.

[Effect]

In the robot control system of the present invention, the movement distance of the movement part of the robot is determined in advance before the start of the movement movement, and a movement movement control pattern suitable for the movement distance is selected, thereby controlling the movement movement of the movement part. , it is possible to perform this under appropriate control depending on the length of the distance.

〔Example〕

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

FIG. 1 is a flowchart for controlling the arm (operating part) of the robot in this embodiment, and corresponds to FIG. 5 above, which was used to explain the conventional robot system.

The robot system of this embodiment basically has the same configuration as the conventional one shown in FIG. 4 above.

In this embodiment, before performing the conventional movement operation of the arm (lla) explained in the flow chart of Fig. 5, the moving distance of the arm (lla) shown in (15) in Fig. 1 is calculated. Based on the calculation result (determination of moving distance), (1
6) Perform the acceleration selection process.

The flowchart of FIG. 2 shows the above-mentioned acceleration selection process (16) in detail, and here a case is shown in which speed control is performed according to acceleration/deceleration patterns of two types of acceleration. That is, the acceleration switching distance is set as a constant reference distance, and the moving distance derived by the calculation in (15) above is
If it is longer than the above acceleration switching distance, select the long distance acceleration as shown in (18), and conversely, if it is shorter than the above acceleration switching distance, select the short distance acceleration as shown in (19). Select acceleration. After selecting the type of acceleration according to the length of the movement distance, the arm (lla
) movement movement.

Arm when long-distance acceleration is selected as above (
The output waveform for driving lla) is the same as that shown in FIG. 6 above. On the other hand, the output waveform when short-distance acceleration is selected is shown in FIG. This FIG. 3 corresponds to the above-mentioned FIG. 7, and the output waveforms shown in both figures are obtained when the arm (lla) is moved the same distance. As described above, in this embodiment, when the moving distance of the arm (lla) is short, the acceleration/deceleration pattern has a vertically elongated trapezoidal shape, that is, the acceleration is larger than that for the long distance.

As explained above, the robot system of this embodiment is
If the moving distance of the arm (lla) is longer than the reference, the arm (lla) is moved according to the acceleration/deceleration pattern for long-distance acceleration, and if it is shorter than the reference, the arm (lla) is moved according to the acceleration/deceleration pattern for short-distance acceleration, which is larger than that for long-distance. It is possible to control the movement movement. Therefore, it becomes possible to move the arm (lla) under appropriate control depending on the moving distance. Therefore, it becomes possible to perform the moving operation of the arm (lla) quickly, and as a result, it becomes possible to shorten the takt time.

Although the present invention has been specifically described above based on Examples, the present invention is not limited to what is shown in the Examples. For example, in the embodiment, two types of acceleration are selected, but three or more types may be selected. By increasing the types of acceleration to be selected in this way, more appropriate control according to the moving distance becomes possible.

Furthermore, although only a trapezoidal acceleration/deceleration pattern is shown as the acceleration/deceleration pattern, the present invention is not limited to this, and any acceleration/deceleration pattern may be adopted.

〔Effect of the invention〕

According to the present invention, the moving operation of the moving part of the robot can be controlled according to the acceleration/deceleration pattern of the acceleration according to the moving distance, so the movement of the moving part can be appropriately controlled and the takt time can be shortened. achieved.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing a control mode of arm movement in a robot system that is an embodiment of the present invention, FIG. 2 is a flowchart showing details of acceleration selection processing in the above control mode, and FIG. 3 is a flowchart showing details of the acceleration selection process in the above control mode. Graph showing the output waveform of the servo I/F when acceleration is selected, 4th
The figure is a schematic explanatory diagram showing the basic configuration of the present embodiment and the conventional robot system, FIG. 5 is a flowchart showing the control mode of the conventional arm movement operation, and FIGS. 6 and 7 are respectively in the conventional robot system. It is a graph showing the output waveform of the servo I/F when the moving distance of the arm is long, and the output waveform when the moving distance of the arm is short. (1)...Robot control unit, (2)...CPU,
(3)...ROM, (4)...RAM. (5)...Interface (1/F), (6)...
・Servo I/F, (7)...Teaching box, (8)...CR
T. (9)...Keyboard. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] In a robot system in which the moving motion of a moving part of a robot is speed-controlled according to an acceleration/deceleration pattern, there is provided a means for detecting the moving distance of the moving part in advance, and a means for determining the acceleration of the acceleration/deceleration pattern according to the detected moving distance. A robot system characterized by comprising: means for arbitrarily selecting.