JPH04167102A - Robot original point returning method - Google Patents

Abstract

PURPOSE:To quickly return a robot to its original point position with no operation of a teaching operating device by setting previously the original point returning shift information and storing the shift positions every time the robot reaches these shift positions. CONSTITUTION:A controller 20 shifts a holding tool 11 of a robot 10 to a shift original point position P1 and then stores numerical value '1' showing the position P1 into a register 21 contained in the controller 20 when the shift of the tool 11 is over. Thereafter the tool 11 is shifted successively to the positions P2 - P7 and numerical values 2 - 7 showing the positions P2 - P7 respectively are stored in the register 21 when the whifts of the tool 11 are over to each shift point. In addition, the individual original point returning shift information is previously set to return the robot 10 to its original point from each shift position. Thus the shift positions are stored in the register 21 every time the robot 10 reaches each shift position. If the robot 10 has an abnormal stop, the original point returning shift information is selected for the relevant shift position where the robot 10 reached. As a result, the robot 10 can be returned to its original point without operating a teaching operating device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for returning a robot to its origin.

[Conventional technology]

If an industrial robot or some other reason causes an abnormal stop,
Conventionally, the following measures have been taken:

a0 The robot is evacuated to a position where it will not interfere with peripheral equipment by operating the teaching device by the operator. and,
A return command is given to the robot to linearly move the robot from the retreated position to a predetermined position, and then the robot is restarted.

b. By operating the teaching device, a program such as a backward program is forcibly executed, thereby moving the robot to a predetermined position. After the movement, the robot is restarted.

[Problem to be solved by the invention]

Each of the above-mentioned treatments requires complicated operations to perform, and therefore can only be performed by a person who is familiar with how to operate a robot. Moreover, it takes time and effort to operate,
Moreover, if the device is operated incorrectly, there is a risk of equipment damage or personal injury.

In view of this situation, an object of the present invention is to provide a method for returning a robot to its origin, which allows the robot to return to its origin without operating a teaching device.

[Means to solve the problem]

The present invention is applied to the case where the robot is moved to a target position while sequentially positioning the robot at each preset movement position. A process of presetting information, a process of storing the reached movement position in a storage means each time the robot reaches each movement position, and a process of storing the reached movement position in the storage means when the robot stops abnormally. A process of moving the robot to the origin based on the origin return movement information is performed.

[Effect]

Each time the robot reaches each movement position, the reached movement position is stored in the storage means. If the robot stops abnormally, the origin return movement information for the reached movement position is selected, and the robot is moved to the origin based on this origin return movement information.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 illustrates a robot 10 to which the origin return method of the present invention is applied. This robot 1° is controlled by a controller 2o shown in FIG. 16, and FIG. 2 illustrates a normal (non-abnormality) processing procedure executed by this controller 20.

As shown in the figure, the controller 20 first moves the gripper 11 of the robot 10 to the movement origin position P1 (step 100), and when the movement is completed, the register 21 built in the controller 20 registers the corresponding A numerical value 1 indicating the position P is stored (step 101).

Then, the gripping tool 11 is moved to the position if P2 (step 102), and when the movement is completed, a numerical value 2 indicating the position P2 is stored in the register 21 (step 103).

At position P2, a heat-treated workpiece 30 for hot forging is placed.
is supplied by the work supply device 12.

Therefore, in step 103, the process of activating the gripping tool 11 and gripping the workpiece 30 with the gripping tool 11 is also executed.

Thereafter, the gripping tool 11 is moved to positions P, , P4 . ....

3. Move sequentially to P, and at the end of movement to those positions, set a numerical value indicating each position. ．． 4. ....

7 is stored in the register 21. In FIG. 2, among the above processes, only the process of storing the numerical value 7 in the register 21 is shown in step 104.

Next, the gripping tool 11 is moved to position P8 (step 105). When the movement is completed, the numerical value 8 indicating the position P8 is stored in the register 21, and the gripping tool 11 is released to load the workpiece 30 into the forging press 40 (step 106).

When the above loading is completed, move the gripping tool 11 to position P9.
+ Plo+ P 11 and movement origin position PI
2(-Pl), and at the end of the movement to those positions, the numerical values 9, 10° 11 and 1 indicating the respective positions.
is stored in the register 21.

In FIG. 2, the process of storing the numerical value 11 in the register 21 is shown in step 107, and the process of moving the gripping tool 11 to position PI2 is shown in step 108.

The arrival of the gripper 11 at the positions P1 to P1□ is detected based on output pulses from the pulse encoder 13 (see FIG. 6) provided on each axis of the robot 10.

Further, confirmation of the gripping operation in step 103 and confirmation of the release operation in step 106 are performed based on the output signal of the gripping detection sensor 14 (see FIG. 6) provided on the gripping tool 11.

Further, the workpiece 30 loaded into the forging press 40 is molded by the press.

By the way, the controller 20 has a function of stopping the robot 10 when an abnormality occurs in the robot 10 or the like due to some reason.

Hereinafter, a process for returning the robot 10 to the movement origin position P when the robot 10 stops abnormally will be described.

FIG. 3 shows the procedure of the origin return process executed by the controller 20.

In this procedure, it is determined whether or not the return switch 22 shown in FIG. That is, a numerical value representing the movement position closest to the stop position among the movement positions already passed is read out from the register 21 (step 201).

That is, for example, when the robot 10 stops between positions P7 and P8, a numerical value representing position P7 is read out from the register 21.

Note that the return switch 22 is operated after the cause of stopping the robot 10 is removed.

Then, it is determined whether or not the gripping tool 11 is gripping the workpiece 30 based on the output signal of the sensor 14 (step 202). Then, in step 203 if the workpiece 30 is being gripped, and in step 204 if the workpiece 30 is not being gripped, the return-to-origin process corresponding to the numerical value read from the register 21 is executed. .

That is, the memory 23 built into the controller 20 stores in advance the origin return procedure corresponding to each movement position P, to P12 for the case where the workpiece 30 is gripped and the case where the workpiece 30 is not gripped.

For example, if the gripping tool 11 stops while gripping the workpiece 30 between positions P7 and P8, in this case, the numerical value 7 representing the position P7 read from the register 21 and the output signal of the sensor 14 are Based on the above memory 2
3 to 4 are read out and executed.

According to this return procedure, the gripper 11 is moved to the workpiece disposal position via positions P7 and P6 (step 20
3-1 to 203-3). The above workpiece disposal position is
This is a preset position on the workpiece disposal box 15 or the chute 16 for guiding the discarded workpieces shown in FIG.

Next, the gripping tool 11 is released and the workpiece 30 is discarded in the workpiece disposal box 15 (step 203-4), and after that, the gripping tool 11 moves to the origin position P via the position P.
1 (steps 203-5, 203-6)
.

Note that the work 30 is discarded for the following reasons.

That is, since the temperature of the workpiece 30 decreases considerably while the gripper 11 is returned to the movement origin position P1,
This is because even if this work 30 is loaded into the press machine 40 again, it will not be possible to perform proper molding.

Next, if the gripping tool 11 stops between positions P7 and P8 without gripping the workpiece 30, in this case, the numerical value 7 representing the position P7 read from the register 21 and the output of the sensor 14 Based on the signal, the memory 2
3 to 5 are read and executed.

According to the return procedure shown in the figure, the gripping tool 11 is at the positions P, , P6.
and P6 to the movement origin position P1 (steps 204-1 to 204-4).

Note that the information read from the memory 23 includes not only information on the return path but also posture information, speed information, etc. of the robot 10 at the time of return. In this case, the stop position is specified based on the numerical value representing the position stored in the register 21 in the same manner as above. Then, the memory 2 stores a corresponding return procedure based on the stop position and the output signal of the sensor 14.
3 and executed.

Although the above embodiment is applied to the loading robot 10 in hot forging, the technology of the present invention can also be applied to industrial robots used for other purposes.

〔Effect of the invention〕

According to the present invention, the robot can be quickly returned to the original position without operating the teaching device. This eliminates the conventional problem of equipment damage or personal injury caused by inexperience with robot operation when returning to the origin, and also improves the robot's operating rate.

[Brief explanation of the drawing]

Fig. 1 is a conceptual diagram showing an example of a robot to which the return to origin of the present invention is applied, Fig. 2 is a flowchart illustrating the movement procedure of the robot, and Figs. Flowcharts showing each processing procedure, and FIG. 6 are block diagrams conceptually showing how the robot controller and peripheral devices are connected. DESCRIPTION OF SYMBOLS 10... Robot, 11... Gripping tool, 12-... Work supply device, 13... Pulse encoder, 14...
・Grip detection sensor, 15... Workpiece disposal box, 20...
- Controller, 21...Register, 22...Home return switch, 23...Memory. Figure 3

Claims (1)

[Claims] Applicable to the case where the robot is moved to a target position while sequentially positioning the robot at each preset movement position, the robot is returned to its origin from each of the above-mentioned movement positions by different homing methods. a process of presetting movement information for the robot; a process of storing the reached movement position in a storage means each time the robot reaches each movement position; and a process of storing the reached movement position in the storage means when the robot stops abnormally. a step of moving the robot to the origin based on the origin return movement information for the robot.