JPH03210603A - Robot teaching point changing device - Google Patents

Abstract

PURPOSE:To reduce the manhour required for teaching data to a robot by producing an attitude conversion matrix based on the inputted torch angles, replacing an attitude matrix with the attitude conversion matrix in regard to an inputted teaching point, and changing absolutely the attitudes in a batch. CONSTITUTION:A teaching point to be changed is selected by a teaching point selection means M3, and the type of a torch angle to be changed in selected by a torch angle selection means M4. Furthermore an attitude conversion matrix production means M5 produces an attitude conversion matrix based on the inputted torch angle. At the same time, an absolute attitude changing means M6 replaces an attitude matrix serving as the teaching point data on the torch which actually performs a welding job with the attitude conversion matrix for the inputted teaching point. Thus the attitudes are absolutely changed in a batch. Otherwise a relative attitude changing means M7 integrates the conversion matrix to the attitude conversion matrix for the inputted teaching point. Thus the attitudes are relatively changed in a batch. As a result, the correction of the teaching point is simplified and also the time and the labor can be reduced for the trial and error of an operator.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a robot teaching point changing device, and more particularly to a device for changing the teaching points of a robot all at once.

[Prior Art] In recent years, welding robots have been used for, for example, arc welding, and as shown in Fig. The torch angles, such as the angle of inclination and the angle of advance, are set to the most preferable values. For example, as one of the techniques for setting the coordinates to optimal values, a technique has been proposed in which the values of the coordinates are changed according to the distortion of the workpiece (Japanese Patent Laid-Open No. 61-25070).
(See Publication No. 5).

In addition, in order to improve the quality of one-way normal welding when welding the above robot, we used a 1:% off-line programming device to set many teaching points such as P(1) to P(n) in Figure 7. Then, welding is performed by adjusting the angle of the torch at these teaching points.For example, teaching points P(1) to P(n)
When changing the toe angle (as shown in Figure 8, first specify the teaching point to be changed (Sl), then specify the rotation axis to be changed (S2)), and input the rotation angle value of each axis. (S3), check whether the change is OK (S4), and confirm.
In this case, the process of changing the torch angle was executed (S5
).

[Problems to be Solved by the Invention] However, the teaching method for teaching points performed using the above-mentioned offline programming device does not necessarily provide a high-quality welding position in one teaching operation, so it is usually necessary to teach several times. There is a problem that point work is required and teaching work takes time.Furthermore, in actual welding work, when it is desired to correct the torch angle along a predetermined welding line,
There is a problem in that it is necessary to correct the angles of all teaching points related to the welding operation, making the operation extremely troublesome.

In other words, when there are many teaching points, there is a problem that the work time for changing the angle becomes long, and furthermore, the work time for confirming that the torch angle has been changed becomes extremely long.

The present invention simplifies the operation of modifying teaching points, and
It is an object of the present invention to provide a robot teaching point changing device that can perform good welding.

[Means for Solving the Problems] The present invention has been made to achieve the above object (as illustrated in Fig. 1), the teaching point data including the torch angle of the welding robot M1 is transmitted to In the robot teaching point changing device that changes by M2, teaching point selection means M3 selects the teaching point to be changed; torch angle selection means M4 selects the type of torch angle to be changed; an attitude transformation matrix creation means M5 for creating an attitude transformation matrix based on the table; and for the inputted teaching points, absolutely all orientations are collectively determined by replacing the orientation matrix with the orientation transformation matrix. Absolute attitude changing means M6 for changing the teaching point, or relative attitude changing means M7 for relatively changing the attitude all at once by multiplying the attitude transformation matrix by a transformation matrix with respect to the input teaching points. The gist of the present invention is a robot teaching point changing device characterized by comprising at least one changing means.

[Operation] As illustrated in FIG. 1 of the robot teaching point changing device 1 of the present invention, the teaching point data including the torch angle of the robot M1 that performs welding is changed by the off-line programming device M2.

Then, the teaching point selection means M3 selects the teaching point to be changed, the torch angle selection means M4 selects the type of torch angle to be changed, and the attitude transformation matrix creation means M5
creates an attitude transformation matrix based on the input torch angle.

At the same time, the absolute posture changing means M6 replaces the posture matrix, which is the teaching point data of the torch that actually performs welding, with the posture conversion matrix for the input teaching points, thereby absolutely changing the posture all at once. and change it. Also IA
The relative attitude changing means M7 relatively changes the attitude of the input teaching points at once by multiplying the attitude transformation matrix by the transformation matrix.

In addition, in the present invention, both of the above-mentioned changing means M6. It is sufficient if at least one of the changing means M7 is provided, but both changing means M6. M
7, it is possible to change the posture both absolutely and relatively.

[Embodiment] Next, a preferred embodiment of the robot teaching point changing device of the present invention will be described in detail based on the drawings. FIG. 2 shows a robot teaching point changing device according to an embodiment of the present invention together with the entire system.
Table: Built-in offline programming device.

As shown in the figure, the offline programming device 1 is connected to an industrial welding robot 2, and the welding robot 2 includes a fixed base 4 for fixing the welding robot 2 and a rotating base 6 for rotating the welding robot 2. further comprising a first arm 8, a second arm 10, a bending shaft 12,
It includes a swing shaft 14, a twist shaft 16, a welding torch 18 to be controlled, and the like.

Furthermore, the robot teaching point changing device (in order to control changes in data at the friend teaching point, etc.) is equipped with an electronic control unit (ECU) 20 shown in FIG.
is a well-known CPU 20a.

ROM20b, RAM20c, backup RAM
20d, input/output port 20e, pass line 20
It is composed of f, etc.

The ECU 20 performs processing such as storing the calculation results and changing the data, as well as inputs from the position sensor 21 etc. that detects the drive position of each drive shaft of the welding robot 2. Also, outputs for controlling the drive motor 22 and the like that drive the welding torch 18 and the like are performed.

When welding is actually performed using this welding robot 2, the (x, yt z) coordinates of the teaching point are set.

By setting the coordinates of the position and posture, it is possible to set the torch angle such as the advancing angle and the inclination angle. In other words, the fourth
As shown in the figure, when joining the upper plate 23 and the lower plate 24 by welding, the welding torch 18 is placed at a predetermined interval (wire extension) from the joining position 1, and the plate material 23.
In addition to determining the inclination angle, which is the angle from 4, the advancing angle, such as the advancing angle or the receding angle, is determined.

Next, control of the welding robot 2 will be explained based on the flowcharts of FIGS. 5 and 6.

First, based on FIG. 5, an outline of the teaching point changing operation performed using the offline programming device 1 will be explained.

First, start up the offline programming device 1 (step 100), create teaching points for setting the welding direction, etc. (step 110), and call the registered teaching points (step 110).
Step 120). Next, robot shape attribute data such as the shape of each wheel of the welding robot 2 and the type and speed of motion are created (step 130), and the registered robot shape attribute data is called (step 140). Next, the teaching point-pattern change, which is a characteristic part of this embodiment which will be described in detail later, is performed (step 150), and the offline programming device 1
Then, the control operation data is outputted to the welding robot 2 (step 160), and the present process ends.

Next, a data conversion formula used in the process of collectively converting teaching point data will be described.

The data of the teaching posture at the teaching point P(i) of the welding robot 2 is expressed by the following equation 0.

NXy, *Z' normal vector ox, 9
t z ”Orient vector AXw, *Z
'Approach vectors
Above It is expressed by the following 0 formula.

Further, the transformation matrix 1 when rotating the advancing angle by a relative value (relative angle) of 80 is expressed by the following equation 0.

Therefore, the matrix of teaching points when rotating to the above relative angle is P (i) θ' = P (i) *, so it is expressed by the following equation 0.

P(1)θ°= ...■ On the other hand, since the inclination angle is a rotation around the shore, its absolute value (
The teaching point matrix when changed to (absolute angle) α is expressed by the following equation 0.

Further, a transformation matrix 1 that rotates the inclination angle by a relative value (relative angle) Δα is expressed by the following equation 0.

Therefore, teaching point matrix 1 table when rotating by relative angle Δα P (i) α' = P (i) *T, so it is expressed by the following equation 0.

P (i) α°= Next, on the basis of FIG. 6, a description will be given of the process of controlling the batch change of the torch angles such as the advancing angle and the inclination angle, which is performed using the above equations 0 to 0.

First, in step 200, it is determined whether or not a command to change the front torch angle and the bracket has been input, and if it is determined that a command to change the torch corner and handle has been inputted, the process proceeds to step 210. Specify the welding robot 2 whose corner is to be changed.

In the following step 220, all teaching points P(1) to P(n) to be changed by one are specified, and the process proceeds to step 230.

In step 230, it is determined whether the changed angle is an advancing angle or an inclination angle, and if it is determined that it is an advancing angle, the process proceeds to step 240.

In this step 240, it is determined whether the advancing angle is the absolute angle θ or the relative angle. If it is determined that the advancing angle is the absolute angle θ, the process proceeds to step 250.

In this step 250, the value of the absolute angle θ is input, and in the subsequent step 260, the value of 1 indicating the order of the position of the teaching point is set to the initial value 1, and in step 270 (using the above equation , P (i) is changed to P(i)θ.

Furthermore, in step 280, 1 yo i is incremented, and in step 290, it is determined whether 1 friend i has reached n, which indicates the end of the teaching point. Here, if it is determined that i is not n, the process returns to step 270 and P(i + 1) θ at the next teaching point (i + 1) is calculated; If 1, proceed to step 300.

In this step 300, the data to be changed obtained as described above is adopted, and it is checked whether or not it is actually allowed to be changed, and if it is allowed to be changed, this process is temporarily terminated.
If the change is not allowed, the process returns to step 200 again.

On the other hand, in step 240, it is determined that the advancing angle is 0 relative to the relative angle, and in step 310, the value of the one-friend relative angle Δθ is input, and in the following step 320, the value of i indicating the order of the position of the teaching point is input. Set the value to the initial value of 1, and proceed to step 32.
0 and 1 friend Using the above ■ formula, P (i) is P (i)
Change to θ°.

Furthermore, in step 340, +2 1 is incremented,
In step 350, it is determined whether or not i over 1 has reached n, which indicates the end of the teaching point. Here, if it is determined that i is not n, return to step 330, calculate P(i + 1) θ at the next teaching point (i + 1),
On the other hand, if it is determined that i=n, step 3 above
Go to 00.

Further, in step 230, the change angle is determined to be an inclination angle, and the process proceeds to step 360 (it is determined whether the inclination angle is an absolute angle α or a relative angle Δα, and if it is an absolute angle α, the process proceeds to step 370). move on.

Hereinafter, the processing from step 370 to step 410 is as follows:
In the processing of steps 250 to 290 above, the only difference is the absolute angle θ of the advancing angle and the absolute angle α of the inclination angle, and the other processes are almost the same except for the calculation processing of step 390, so the explanation will be omitted. . Furthermore, this step 39
0, P(1) is defined as P(i)α using the above formula ■
Change to

On the other hand, if it is determined in step 360 that the inclination angle is the relative angle Δα, the process proceeds to step 420.

Hereinafter, the processing from step 420 to step 460 is as follows:
In the processing of steps 310 to 350 above, the only difference is that the relative angle of the advancing angle is changed to the relative angle of the inclination angle Δα, and the other processes are almost the same except for the calculation processing of step 440, so the explanation will be omitted. do. In addition, in this step 440, P (i) is converted to P (
i) Change to α°.

As described above, in this embodiment, the data at each teaching point is changed all at once using the above formulas (1) to (2), which has the effect of significantly reducing the number of teaching steps. In addition, by changing the torch angle, if the operator cannot reach the teaching point while holding the changed torch angle posture, the operator will know before actually teaching, reducing the number of man-hours and significantly reducing the time required for trial and error. There is an advantage to doing so.

Furthermore, since there are two ways to change the angle, absolute angle and relative angle, it is possible to use both methods for efficient work, such as when the indicated angle is fixed or when making fine adjustments to the angle.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it goes without saying that it can be implemented in various forms without departing from the gist of the present invention. be.

[Effects of the Invention] As detailed above, the robot teaching point changing device of the present invention selects the teaching point to be changed, selects the type of torch angle to be changed, and further changes the posture based on the input torch angle. At the same time as creating a matrix, for the input teaching points, either the attitude matrix is replaced with an attitude transformation matrix to determine the orientations absolutely, or the orientations are determined relatively by multiplying the transformation matrix by the orientation transformation matrix. Since the data can be changed all at once, the number of man-hours required to teach data to the robot can be significantly reduced.

Furthermore, based on the data, it is possible to check whether the data of the teaching point is actually appropriate or not, which has the effect of reducing the amount of time and effort required for the operator to perform trial and error.

[Brief explanation of drawings]

FIG. 1 is an illustration of the basic configuration of the present invention, FIG. 2 is a system configuration diagram of an embodiment, FIG. 3 is a block diagram showing an electronic control device, FIG. 4(a) is an explanatory diagram showing an inclination angle, Figure 4(b)
5 is an explanatory diagram showing the advancing angle, FIG. 5 is a flowchart showing an outline of the posture teaching method, FIG. 6 is a flowchart showing detailed control of posture teaching, FIG. 7 is an explanatory diagram showing the conventional welding method, and FIG. The figure is a flowchart showing a conventional posture teaching method. 1 2 3 4 5 6 7 8 0 Bots offline programming device Teach point selection means Torch angle selection means Attitude transformation matrix creation means Absolute attitude change means Relative attitude change means Offline programming device Welding robot Welding torch

Claims (1)

[Scope of Claims] 1. A robot teaching point changing device for changing teaching point data including a torch angle of a robot performing welding using an offline programming device, comprising teaching point selection means for selecting the teaching point to be changed; A torch angle selection means for selecting the type of torch angle to be changed; and an attitude transformation matrix creation means for creating an attitude transformation matrix based on the input torch angle, and with respect to the input teaching point, Absolute posture changing means that absolutely changes the posture all at once by replacing the posture matrix with the posture conversion matrix, or multiplies the conversion matrix with the posture conversion matrix for the input teaching points. A robot teaching point changing device comprising at least one of relative posture changing means for relatively changing postures all at once.