JPS59135508A - Industrial robot - Google Patents

Abstract

PURPOSE:To obtain an industrial robot which can facilitate an easy manual remote control of the relative position to a work by setting a fixed direct- traveling control axis to an end effector and giving a manual remote control to the end effector along said control axis. CONSTITUTION:An operator operates a switch SM to set a manual mode and then operates a switch SW to set a working point P existing before a torch 2 at P1 to fix the positions phi and THETA of a robot. The distance between the torch 2 and a work WK is controlled with operation of the switch SW. A computer 5 calculates the increased value of an X system control axis to control the position of the torch 2 toward an axis T. Then the switch SM is set in an automatic mode after controlling the torch 2 at a position P2 and setting various conditions including the speed, etc. Then the step contents of a user program are successively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the improvement of industrial robots, and particularly to a BRAIN type robot capable of manual remote position control, which facilitates teaching operations.

Industrial robots such as those described above are well known.

The mechanical configuration of the robot is configured according to various purposes, such as rectangular coordinates, cylindrical coordinates, and multiple joints. However, during manual remote position control, in addition to these mechanical control axes, the control device includes control axes based on orthogonal coordinates to facilitate manual operation. (For example, Japanese Patent Laid-Open No. 139810/1983).

In a robot configured in this manner, the end effector is controlled in a straight line by the Cartesian coordinate control system due to manual operation by the operator. For example, when a welding torch is used as the end effector,
If you want to adjust the distance between the torch and the workpiece by moving the torch forward and backward only in the front-rear axis direction, multiple axes may be It must be done simultaneously and under control.
Its operation is not easy.

Therefore, the present invention attempts to solve the above-mentioned problems by providing an industrial robot that can be easily manually controlled in a direction fixed to an end effector.

The outline of the present invention is a playback type industrial robot in which the relative positions of an end effector and a workpiece can be manually and remotely controlled in a manual mode of a control device, wherein the control device includes: (a) the end effector; (b) means for manually remote controlling the end effector along the set straight-travel side, leg axis;

It includes.

An embodiment of this invention will be described in detail below with reference to the drawings. This embodiment is an articulated robot that uses a welding torch as a welding/effector, but the invention is not limited to this embodiment. 01 is an industrial robot, and in this embodiment, As shown in the figure, it is an articulated robot having five rotational degrees of freedom α1 to α5. The robot 1 is equipped with a MIG welding torch 2 as an end effector.

3 is a conduit tube that guides the consumable electrode TW of the torch 2.

4 is a known welding power supply device. The device 4 includes a spool 4a that winds up the consumable electrode TW of the torch 2, and
It is configured such that a welding power source 4b can be connected between W and the workpiece WK.

Reference numeral 5 denotes a known computer as a main part of the control device of this embodiment. Computer 5 includes a CPU and memory.

A power supply 4b is connected to the pass line B of the computer 5.

The pass line B is further connected to a servo system Sα1 for the α1 axis of the robot R. The servo system Sαl includes a power Mα1 for the α1 axis and an encoder/coder Eα1 that outputs its position information. Also, for pass line B, α
2-axis servo system Sα2, α3-axis servo system Sα3, α4
A servo system Sα4 for the axis and a servo system Sα5 for the α5 axis are connected.

-RE is a remote control panel that forms part of the control device,
A manual operation snap switch group SW is provided.

Then, set the snap switch for each side leg axis (Cartesian coordinate axes fixed to the base 1a of the robot 1 for control) of x, y, z, Φ, and θ to the UJ side. The end effector is configured to move in the opposite direction by tilting it toward the "D" side in the direction in which position information increases. It is assumed that the control axes Φ and θ respectively represent a turning angle and an attitude angle with respect to the orthogonal coordinate axes. In these configurations, an algorithm is required for coordinate conversion by the computer 5 between the multi-joint system of the mechanism and the orthogonal coordinate system of the control. However, since the details are well known, they will not be described in detail.

The operation panel RE is also provided with a speed command rotary switch Sv in auto mode. In addition, a mode L changeover switch SM is provided, allowing manual mode M.

It is configured so that it can be switched to test mode TE and auto mode A. SE is a selection switch, and by switching it upward in the figure and operating the up/down switch SU, the welding condition number W is displayed and selected. Furthermore, by setting this switch SE to the left as shown in the figure and operating the switch SU, each mode is selected and displayed as either linear interpolation "L" or circular interpolation "C". There is. Furthermore, the operation panel RE is provided with a start switch ST. The function of the switch ST will be explained in detail in the explanation of the operation described later.

Furthermore, the operation panel RE is provided with a control axis setting snap switch SWT, which is a feature of the configuration of the present invention. Similarly, it is assumed that the switch SWT is configured so that when it is pushed to the rUJ side, the end effector moves in the Σ direction in which the position information increases, and when it is pushed to the "D" side, the end effector moves in the opposite direction. In addition, in this embodiment, the control axis “T” is set.
” is the longitudinal axis of the torch 2.

Each of the above-mentioned snap switches SU, SW, 5WT (1 stick) is assumed to be in the neutral position in the illustrated state.

Each of the aforementioned switches is also connected to the path line B.

As shown, the workpiece WK has a horizontal corner welding line WL, and welding is to be performed from point P1 to P2 on this welding line WL-.

For this purpose, first, teaching of the user program is executed. In the following description, please also refer to FIG.

The operator operates switch SM to set manual mode. If one of the switches sw is then operated, the position and orientation of the torch 2 is controlled along the X-system control axis. First, set the operating point P in front of the torch 2 to the point P
1, and its attitude (Euler angles, that is, Φ and θ) is determined as appropriate. In this case, torch 2 is the workpiece W.
If you teach at a position too close to the consumable electrode TW during welding, the protrusion length of the consumable electrode TW will increase (so-called extension length).
becomes short and the welding current becomes excessive. On the other hand, if the torch 2 is taught at a position that is too far away from the workpiece W, the welding current during welding will be too small, and the welding result will be unsatisfactory. Therefore, the operator must pay close attention to the positioning of the torch 2 in the longitudinal axis T direction. In that case, it will be understood that it is difficult to operate only by operating the switch SW.

Therefore, the operator determines the Euler angle Φθ of the torch 2 and the direction toward the point P1 using the switch SW, and then operates the switch SWT.

The computer 5 judges this (processing PRI) and calculates △t
x=-sinθ·SinΦ Δty=sinθ” cosΦ Δtz=cosθ are calculated (processing PR2).

Next, the computer 5 determines whether the stick of the switch SWT is pushed to the U side or to the D side (
Processing PR3).

If it is knocked down to the U side, Δtx=−Δtx Δty=−Δty Δtz=−Δtz (processing PR4). If it is knocked down to the D side, leave it as it is.

Then, the computer 5 further calculates △X = V c aΔtlI△tx △Y = V c・△t・△ty △Z = V c・△t・Δtz △θ=0 △Φ=0 (processing PR5) . Here, ■c is the command speed (in this case, the moving speed of the torch 2 during predetermined teaching), and Δt is the system time (for example, 20
0 Tobi C).

The increment value Δ for each axis of the X-system control axes obtained in this way
In order to convert
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It is best known for the article ``Theses''.

Further, the current position information αp of each axis of the α system is used to determine the position information to be commanded. is obtained using the following formula (processing PR7)
.

Sorry. = αp10△The command position information section thus obtained. Output (processing PR
8).

Furthermore, it is not determined whether the switch SWT has been operated or not (processing PR9); if it has been operated, the process returns to process PR6, and the above-described operation is repeated until the switch SWT is no longer operated. When the switch SWT is operated anew, the operation is newly started from the process PR1.

Thus, while the operator turns the switch SWT to the Ut or D side, the torch 2 moves forward or backward in the direction of the axis T, and the distance between the torch 2 and the workpiece W can be easily adjusted.

In this way, the operator controls the position of the torch 2 to points P1 and P2, sets the moving speed in auto mode with switch sv, linear interpolation with switch SE, sets command information such as welding conditions WNl, and switches S
By operating switch T, the command information for each step of the user program is stored in the memory of the computer 5.b Thereafter, the operator further sets the test mode with switch SM, and each time the operator operates switch ST, Each step of the program is executed (except for welding). And correct any errors.

Further, the operator sets the auto mode using the switch SM and operates the switch ST to sequentially execute the contents of the steps of the user program. in this case,
As mentioned above, good welding results can be obtained by providing means for detecting the welding current and remotely controlling the torch 2 to approach the workpiece WK in the direction of the axis T so that the detected value is equal to the set value. can be expected.

In addition to the embodiments described above, this invention can also be modified as described below.

(a) The mechanical configuration of the industrial robot may be a rectangular coordinate system, a polar coordinate system, a cylindrical coordinate system, etc., in addition to multi-jointed robots. However, as long as the control system has a rectangular coordinate system, including one having a mechanical coordinate system, the present invention can be implemented by setting a fixed linear control axis in the end effector.

(b) As an end effector, in addition to a welding torch,
For example, a plasma cutting torch or the like may be used, and the longitudinal axis may similarly be a linear control axis fixed to the end effector. This case is also useful because it is necessary to accurately teach the distance between the plasma cutting torch and the workpiece. Further, as described above, it is also possible to control the distance between the torch and the workpiece in the auto mode according to the current value.

Further, a gripping means may be used as the end effector, and the longitudinal axis may similarly be a linear control axis fixed to the end effector. In this case as well, it is possible to easily control the forward and backward position of the opened gripper and step by approaching the workpiece from the side (controlling the tip or base of the gripping claw of the gripping means). be. Other end effectors could similarly be implemented.

(c) Other replacements of each structure with equivalents within the scope of the technical idea of this invention are also included in the wave layered scope of this invention.

As described above, the present invention is unique to the end effector and can easily be controlled in a straight line in the required direction when manually and remotely controlling the end effector, making teaching easy. It can have a remarkable effect.

[Brief explanation of drawings]

The drawings all show one embodiment of this invention, with FIG. 1 being an overall block diagram including a perspective view, and FIG. 2 being a flow chart. 1...° industrial robot, 2... welding torch (end effector), 5... computer, RE... remote control panel, T... linear control axis, WK... workpiece. Applicant ShinMaywa Industries Co., Ltd.

Claims (3)

[Claims] (1) In a playback type industrial robot in which the relative positions of an end effector and a workpiece can be controlled manually and remotely in the manual mode of the control device, the control device includes the following means. robot. (a) means for setting a fixed linear control axis on the end effector; (b) means for manual remote position control of the end effector along the set linear control axis. (2) The industrial robot according to claim 1, wherein the end effector is a torch, and the linear control axis is a longitudinal axis of the torch. (3) The industrial robot according to claim 1, wherein the end effector is a gripping means, and the linear control axis is a longitudinal axis of the gripping means.