JP2760125B2 - Robot controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention provides a quick and minimal damage to a robot when the robot is stopped due to interference with an obstacle when teaching the robot. The present invention also relates to a robot control device that can easily retreat a robot by manual operation.

(Prior Art) With the progress of automation technology in recent years, various types of robots are used in various production plants.

In the case of a general robot, teaching (teaching) to teach the required work operation to the robot in advance
An operation called is required. Conventional teaching work is performed, for example, as shown in FIG.

The robot 1 shown in the figure is a so-called articulated robot, which has six robot axes (hereinafter simply referred to as "axes"), and various movable parts such as a spindle 2, an arm 3, and a hand 4 correspond to each axis. 6-axis robot driven by six drive motors (not shown). This robot 1
Are controlled by the control device 5 that performs feedback control on the drive motors. The controller 5 is connected to a teach pendant (hereinafter simply referred to as a “pendant”) 6 for an operator to input information relating to the operation of the robot 1.

The pendant 6 includes a switch for individually moving each drive motor, and the switch 1
A switch or the like is provided for storing the position of each axis when the (each movable part) is positioned. The pendant 6 has a JOG mode in which the operator can individually drive the drive motor as described above, and a playback mode (hereinafter simply referred to as a “PB mode”) for automatically operating the robot 1 in accordance with the operation stored in this mode. ) Is provided. The operator performs the PB operation of the robot 1 taught in the JOG mode.
You can check by mode. That is, by operating these switches, the operator can perform a teaching operation and cause the robot 1 to perform a desired operation.

However, in such a teaching operation, if the operator mistakes the operation of the pendant 6 in the JOG mode during the operation, the robot 1 makes contact with an obstacle such as another production facility or stores the operation. When the robot 1 is automatically operated in the PB mode, the robot 1 may come into contact with the obstacle, because the obstacle in the movement path of the robot 1 is not considered. Conventionally, in such a case, the robot 1 is first stopped in an emergency, and then the operator observes the movement of the robot 1 in the JOG mode,
Robot 1 from the position where it interfered, that is, the position where emergency stop
Is being evacuated.

For this reason, in the conventional robot 1, the moving direction of each axis corresponding to the rotation direction of each drive motor can be determined at a glance so that the moving direction (or operating direction; the same applies hereinafter) of the robot 1 (each movable part) can be determined at a glance. Is attached. With this marker 7, the operator can control the robot 1
The evacuation direction of the robot 1 is determined according to the emergency stop state, and the robot is evacuated by manual operation.

(Problems to be Solved by the Invention) However, in the case where the robot 1 is manually evacuated by relying on the marker 7 as described above, if the operator mistakes the operation of the pendant 6, the robot 1 is thereby re-established.
May come into contact with obstacles and spread the damage.

Particularly, in the case of the multi-axis robot 1 as shown in FIG. 4, the operation of the robot 1 is complicated because it is formed by synthesizing the movements of many axes. Since the operation tends to be complicated, it takes time for the operator to retreat the robot by manual operation, which is inefficient.

The present invention has been made to solve such a conventional problem, and when the robot comes into contact with an obstacle or the like to stop the robot in an emergency manner, the damage can be quickly and easily minimized while minimizing damage. It is another object of the present invention to provide a robot control device capable of retreating a robot by manual operation.

(Means for Solving the Problems) To achieve the above object, the present invention provides a drive motor for driving a robot axis for moving a movable part of a robot,
Detecting means for detecting the current position of the robot axis, and motor control means for controlling the drive motor based on preset target position data and current position data detected by the detecting means; In a robot control device for controlling the operation of the robot by controlling the drive motor by a control means and positioning the movable part, start position data of the robot axis when the movable part starts moving is stored. A first storage unit, a second storage unit that stores stop position data of the robot axis when the movable unit stops moving, and a second storage unit that stores the data based on the contents of the first storage unit and the second storage unit. Calculating means for calculating a moving amount and a moving direction of the robot axis from when the movable part starts moving to when the movable part stops, and a predetermined switch. A display means for displaying the contents calculated by the calculation means when the switch is ON, and preventing the robot axis from moving in the movement direction calculated by the calculation means when a predetermined switch is ON. And interlock control means for outputting a signal to the motor control means.

(Operation) The present invention configured as above operates as follows.

The first storage unit stores start position data of the robot axis when the movable unit (robot) starts moving, and the second storage unit stops the robot axis when the movable unit (robot) stops moving. The position data is stored. The calculation means is:
Based on the contents of the first storage means and the second storage means, the movement amount and the movement direction of the robot axis from when the movable part (robot) starts moving until it stops are calculated. More specifically, the start position data stored in the first storage means is subtracted from the stop position data stored in the second storage means to calculate the amount of movement of the robot axis. The movement direction of the robot axis is calculated by (increase / decrease of position data).

The display means, when the predetermined switch is turned on, displays the content calculated by the calculation means, that is, the movement amount and movement direction of the robot axis immediately before the robot stops. For example, if the operator makes an emergency stop of the robot due to contact with an obstacle for some reason during the operation of the robot, when the operator turns on the switch,
The display means displays the movement amount and the movement direction of the robot axis immediately before the emergency stop, which are obtained by the calculation means. Therefore, the operator can recognize the movement amount and the movement direction of the robot axis necessary for retracting the robot by looking at this.

Also, the interlock control means is provided when a predetermined switch is
When it is ON, a signal for preventing the robot axis from moving in the movement direction calculated by the calculation means is output to the motor control means. Thereby, the robot axis is prevented from moving in the movement direction before the stop, and can move only in the direction opposite to the movement direction before the stop. For example, if the operator turns the switch off when the operator makes an emergency stop because the robot comes into contact with an obstacle for some reason during the operation, the interlock control means will immediately turn off the emergency stop calculated by the calculation means. A signal for preventing the robot axis from moving in the moving direction is output to the motor control means. Therefore, even if the operator makes a mistake when performing an operation of retreating the robot by manual operation, the robot does not contact the obstacle again.

Hereinafter, a robot control device according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing one embodiment of a robot control device according to the present invention, and FIG. 2 is a diagram showing a specific example of contents displayed on the display device of FIG. FIG. 3 is a flowchart showing the operation of this embodiment. The robot controller described here controls the operation of the six-axis robot in the same manner as the conventional one. However, since the contents of control for each drive motor are all the same, one drive is used here. Only control of the motor will be described, and description of control of the other drive motors will be omitted.

As shown in FIG. 1, this robot control device includes a teach pendant (hereinafter also simply referred to as a “pendant”) 10 operated by an operator when performing a teaching operation, similarly to the conventional robot control device.

The pendant 10 includes a mode changeover switch for switching between the JOG mode and the PB mode and a JO
Operation consisting of a manual switch for manually operating individual drive motors in the G mode, a memory switch for storing the position of each axis when the robot (each movable part) is positioned by this manual switch, etc. A switch 11 and an emergency stop switch 12 for performing an emergency stop of the robot when there is an abnormality in the operation of the robot or when the robot comes into contact with other equipment or the like are provided.

Also, the pendant 10 has a display request switch 13 for displaying the moving amount and moving direction of each axis immediately before the robot stops when the emergency stop switch 12 causes the robot to make an emergency stop. A display end switch 14 for ending the display is provided.

Furthermore, the emergency stop switch 12 is turned on for the pendant 10.
When the robot is emergency-stopped, an interlock switch 15 for preventing the robot from moving in the moving direction immediately before the emergency stop of the robot and a reset switch 16 for ending this control are provided. ing.

The pendant 10 includes the switches 11 to 16 described above.
In addition to the above, a display device 17 for displaying the movement amount and movement direction of each axis when the display request switch 13 is turned on is provided. The pendant 10 configured as described above is provided with a display control unit 18 as a calculation unit and an interlock control unit.
It is connected to the.

The display control unit 18 has a function of calculating the movement amount and movement direction of each axis to be displayed on the display device 17. The display control unit 18 has three registers for storing data for calculating the movement amount and the movement direction, that is, a first register 19, a second register 20 as a first storage unit, and a second storage unit. Are connected to each other.

The display control unit 18 is connected to a motor control unit 23 as a motor control unit, and necessary data is supplied from the motor control unit 23 to the first register 19 and the third register 19.
Output to 21.

The motor control unit 23 includes an operation switch 11 of the pendant 10.
The operation state of the emergency stop switch 12 is input, and the motor control unit 23 operates to move various movable parts such as a robot arm, a main shaft, and a hand in accordance with the operation state of the switches 11 and 12, as in the related art. The drive motor 22 that drives the robot axis is controlled.

The motor control unit 23 is connected to a memory 24 that stores target position data for positioning the robot (each movable unit) in order to cause the robot to perform a predetermined operation.

The target position data is data relating to the movement target position of each axis, that is, the target rotation angle of the drive motor 22, and the operator operates the operation switch 11 in the JOG mode using the pendant 10 to perform the teaching work in the same manner as in the related art. By doing so, they are sequentially set.

Further, a pulse generator (hereinafter, referred to as “PG”) 25 as a detecting means for detecting the rotation angle of the drive motor 22 is connected to the motor control unit 23. This PG25
Outputs a pulse signal corresponding to the rotation of the main shaft of the drive motor 22. The motor control unit 23 can detect the rotation angle of the drive motor 22 by counting the pulse signals.

Further, when the mode changeover switch among the operation switches 11 is set to the PB mode, the motor control unit 23 sequentially inputs the target position data from the memory 24, and inputs the rotation angle detected by the PG 25. A drive signal for driving the drive motor 22 is output until the drive signal matches the target position data. The drive signal is converted in signal form by the D / A converter 26, then amplified by the amplifier 27 to become drive power, and supplied to the drive motor 22. Thus, the motor control unit 23 drives the drive motor 22 according to the input target position data. That is, the motor control unit 23 performs feedback control of the drive motor 22 by the PG 25, and
Drive motor according to the target position data set in 24
The robots 22 are sequentially driven to operate the robot (each movable unit) as taught.

Further, when the mode changeover switch among the operation switches 11 is set to the JOG mode, the motor control unit 23 operates the manual switch among the operation switches 11 by the operator.
The drive signal is output while the switch is ON to drive the drive motor 22, and when the manual switch is turned OFF, the output of the drive signal is stopped and the drive motor 22 is stopped. That is, in the JOG mode, the motor control unit 23
Is designed to drive the drive motor 22 corresponding to the manual switch operated by the operator only while the manual switch is ON. Thereby, the operator can arbitrarily position the robot (each movable part).

Then, in the JOG mode, when the operator releases the hand from the manual switch to stop the drive motor 22, the motor control unit 23 that controls the drive motor 22 in this way, the current position newly positioned thereby is The rotation angle (hereinafter referred to as “current rotation angle”) is detected by the PG 25, and the current rotation angle is output to the third register 21. That is, the third register 21 stores the current rotation angle corresponding to the current position of each axis when the robot (each movable unit) stops moving. Thereafter, the motor control unit 23 outputs to the display control unit 18 a positioning completion signal indicating that the robot (each movable unit) has stopped and positioned.

Further, in the PB mode, when the rotation angle of the drive motor 22 detected by the PG 25 matches the target position data input from the memory 24 and stops the drive motor 22, the motor control unit 23 The position data, that is, target position data input for positioning this time (hereinafter, referred to as “current target position data”) is output to the first register 19. After that, a positioning completion signal indicating that the robot (each of the movable parts) has stopped and has been positioned is output to the display control unit 18.

Further, the motor control unit 23 sets the emergency stop switch 12 to ON.
When the drive motor 22 stops in an emergency, the current rotation angle at the time of the emergency stop is detected by the PG 25, and the current rotation angle is output to the third register 21. After that, an emergency stop signal indicating that the robot has come to an emergency stop is displayed on the display control unit 18.
Output to

Display control unit 18 for inputting the above signal from motor control unit 23
In the JOG mode, before the positioning completion signal is output from the motor control unit 23, that is, the positioning of the robot (each movable unit) is not completed and the robot (each movable unit)
While the is moving, the rotation angle at the previous positioning (hereinafter referred to as “previous rotation angle”) already stored in the third register 21 is stored in the second register 20. That is, the display control unit 18 determines the last rotation angle corresponding to the starting position of each axis when the robot (each movable unit) starts moving to the second rotation angle.
It is stored in the register 20. When the positioning control signal is input from the motor control unit 23, the display control unit 18 inputs the current rotation angle newly output to the third register 21 and stores the current rotation angle in the second register 20 based on the current rotation angle. The amount of movement of each axis from the previously positioned position is calculated by subtracting the previous rotation angle. In addition, the display control unit 18 determines whether the current rotation angle has increased from the previous rotation angle in the plus (+) direction, and vice versa, based on the result of subtraction of the movement direction of each axis from the previously positioned position. , When it is decreasing, it is determined to be in the minus (−) direction.

In addition, in the PB mode, the display control unit 18 controls the motor control unit when positioning the previous time during the movement of the robot (each movable unit) before the positioning completion signal is output as in the case of the JOG mode. The target position data (hereinafter, referred to as “previous target position data”) that has been input to 23 and already stored in the first register 19 is stored in the second register 20. That is, the display control unit 18 causes the second register 20 to store the previous target position data corresponding to the starting position of each axis when the robot (each movable unit) starts moving. And the display control unit
When a positioning completion signal is input from the motor controller 23, the current target position data newly output to the first register 19 is input, and the previous target position stored in the second register 20 from the current target position data is input. By subtracting the data, the movement amount of each axis from the position determined last time is calculated. In addition, the display control unit 18 determines whether the current target position data has increased from the previous target position data in the plus (+) direction based on the result of the subtraction of the movement direction of each axis from the previously positioned position. On the other hand, if it has decreased, it is determined to be in the minus (-) direction.

Further, when the emergency stop signal is input in the PB mode, the display control unit 18 inputs the current rotation angle output from the motor control unit 23 to the third register 21 and outputs the current rotation angle to the second register 20 based on the current rotation angle. Is subtracted from the previously stored target position data to calculate the movement amount of each axis from the previously positioned position to the emergency stop position. The display control unit 18
Determines the moving direction of each axis immediately before the emergency stop in the same manner as described above. In JOG mode,
When the robot comes to an emergency stop, the operator turns on the manual switch.
Since the signal is turned off, a positioning completion signal is output from the motor control unit 23 to the display control unit 18, whereby the display control unit 18
Can determine the movement amount and the movement direction of each axis from the previously positioned position to the emergency stop position.

Further, when the display request switch 13 of the pendant 10 is turned on, the display control unit 18 displays the movement amount and the movement direction calculated in each mode until the display end switch 14 is turned on in FIG. As shown in FIG. At this time, as shown in FIG. 2, the display control unit 18 blinks such information (movement amount / movement direction) of the axis having the largest movement amount.

Therefore, if the operator turns on the display request switch 13 when the robot makes an emergency stop, the movement amount and the movement direction of each axis from the previously positioned position to the emergency stop position are displayed on the display device 17. The operator can recognize the movement amount and the movement direction of each axis necessary for retreating the robot, and can easily perform a manual operation for retreating the robot. Display request switch 13 is ON.
Then, the movement amount and movement direction of each axis are displayed on the display device 17 according to the operation of the robot in each mode,
The operator can check the movement of the robot during operation.

Further, when the interlock switch 15 of the pendant 10 is turned on, the display control unit 18 outputs an interlock signal to the motor control unit 23. The motor control unit 23 that has received the interlock signal applies an interlock in the rotation direction of the drive motor 22, and prevents the drive motor 22 from rotating in the rotation direction immediately before the input of the interlock signal.

Therefore, if the interlock switch 15 is turned on when the operator makes an emergency stop of the robot, the robot (each movable part) does not move in the moving direction immediately before the robot stops, and the operator retreats the robot. Even if a mistake is made in performing the manual operation for causing the robot to operate again, it is possible to prevent the robot from coming into contact with an obstacle or the like again to increase the damage. In addition, the operator drives the drive motor 22 of the axis corresponding to the blinking movement amount and the movement direction sequentially by manual operation, and drives the drive motor 22 in order from the one with the largest movement amount to efficiently operate the robot. It can be evacuated quickly.

The robot control device thus configured operates according to the flowchart shown in FIG. Note that a program corresponding to this flowchart is executed by the display control device 18. Further, the control performed by the motor control unit 23 on the drive motor 22 when the operation switch 11 and the emergency stop switch 12 are turned on is the same as in the case of a conventional general robot control device. The description of the operation is omitted.

First, the display control unit 18 inputs the operation state of the mode change switch in the operation switch 11, and sets the current mode to JO.
It is determined whether or not the mode is the G mode (step 1).

If the current mode is the JOG mode as a result of this determination, the display control unit 18 enters a state in which the positioning completion signal is not output from the motor control unit 23, that is, a state in which the robot (each movable unit) is moving. (Step 2), and when it is in a moving state, a data transfer process for storing the previous rotation angle already stored in the third register 21 in the second register 20 is performed (step 3).

Thereafter, the display control unit 18 waits until a positioning completion signal is output from the motor control unit 23 (step 4), and when the positioning completion signal is input from the motor control unit 23, the positioning of the robot (each movable unit) is completed. Then, the current rotation angle newly output from the motor control unit 23 to the third register 21 is input, and the previous rotation angle stored in the second register 20 in step 3 is subtracted from the current rotation angle. Then, the movement amount of each axis is calculated, and the movement direction of each axis is determined based on the subtraction result as described above (step 5).

Thereafter, the display control unit 18 determines whether or not the flag n of the internal memory for storing that the display request switch 13 has been turned on is 1 (step 6), and the flag n is already 1 In this case, the process proceeds to step 9 immediately.
On the other hand, if the flag n has not become 1, the display request switch 13 is turned on to determine whether or not the display of the movement amount and the movement direction has been requested (step 7). If not, the process immediately proceeds to step 10. If requested, however, 1 is substituted for the flag n and the fact that the display request switch 13 has been turned on is stored in the internal memory (step 8). Go to 9.

In step 9, the display control unit 18 outputs the movement amount and the movement direction obtained in step 5 to the display device 17, and causes the display device 17 to display the information (see FIG. 2).

Then, the display control unit 18 sets the interlock switch
It is determined whether or not 15 has been turned on (step 10). If the interlock switch 15 has not been turned on, step
Proceed to 13 and if it is turned on, output an interlock signal to the motor control unit 23, and drive motor so that the robot (each movable unit) does not move in the movement direction obtained in step 5.
Apply an interlock in the 22 rotation directions (Step 1
1).

Thereafter, it is determined whether or not the reset switch 16 has been turned on (step 12). If the reset switch 16 has not been turned on, the process returns to step 6 and the reset switch 16 is turned on.
The interlock continues to be applied in the rotation direction of the drive motor 22 until is turned on, and when the reset switch 16 is turned on, the output of the interlock signal is stopped and the drive motor 22 is stopped.
Release the interlock for the 22 rotation direction.

Thereafter, the display control unit 18 determines whether or not the display end switch 14 is turned on and a request to end the display of the movement amount and the movement direction is made (step 13), and the display end switch 14 is turned on. If not, the flag n is kept at 1, and if the display end switch 14 is turned on,
By substituting 0 for the flag n (step 14), the above operation is repeated.

On the other hand, the current mode is
If the mode is not the JOG mode, it is further determined whether or not the mode is the PB mode (step 15). If the mode is not the PB mode, the process waits until the mode becomes either the JOG mode or the PB mode.

On the other hand, in the PB mode, the motor control unit
Wait until the positioning completion signal is not output from 23, that is, until the robot (each movable unit) is in a moving state (step 16). When the robot is in a moving state, the previous state already stored in the first register 19 is stored. Data transfer for storing the target position data in the second register 20 is performed (step 17).

Thereafter, the display control unit 18 waits until a positioning completion signal or an emergency stop signal is output from the motor control unit 23 (Steps 18 and 19).

When the display control unit 18 receives the positioning completion signal from the motor control unit 23 (step 18), the display control unit 18 determines that the positioning of the robot (each movable unit) has been completed, and sends the first register from the motor control unit 23 to the first register. Input the current target position data output to step 19 and execute step 17 from this current target position data.
Then, the previous target position data stored in the second register 20 is subtracted to calculate the movement amount of each axis, and based on the subtraction result, the movement direction of each axis is determined as described above (step 20). Then, the process proceeds to step 6, where the information is displayed on the display device 17 when the display request switch 13 is turned on.

On the other hand, when an emergency stop signal is input from the motor control unit 23 (step 19), it is determined that the robot has stopped emergency during the automatic operation in the PB mode, and the process proceeds to step 5.
The current rotation angle output from the motor control unit 23 to the third register 21 is input, and the previous target position data stored in the second register 20 in step 17 is subtracted from the current rotation angle,
The amount of movement of each axis from the previously positioned position to the emergency stop is calculated, and based on this subtraction result, the direction of movement of each axis immediately before the emergency stop is determined, and the information request display switch 13 is turned on. Is displayed on the display device 17 when it is displayed.

As described above, according to the present embodiment, in the JOG mode, when the operator turns on the display request switch 13, the operator operates the manual switch to operate the robot (each movable unit).
Each time is positioned by manual operation, the movement amount and movement direction of each axis are displayed on the display device 17. And, for example,
When the interlock switch 15 is turned ON when the operator mistakenly operates the manual switch and causes the robot to emergency stop because the robot interferes with an obstacle or the like,
Interlock is applied in the rotation direction of the drive motor 22,
Since the movement in the moving direction immediately before the emergency stop of the robot is prevented, the damage of the robot due to the interference with the obstacle or the like again does not occur. Moreover, since the movement amount and movement direction of each axis in the emergency stop state remain displayed on the display device 17, the operator can easily operate the robot by operating the manual switch while watching the display device 17. The robot can be evacuated, and the robot can be evacuated efficiently and quickly.

Also, in the PB mode, when the operator turns on the display request switch 13, every time the robot (each movable unit) is automatically positioned by the motor control unit 23, the movement amount and the movement direction of each axis are displayed on the display device 17. Will be displayed. And
For example, if the operator turns off the interlock switch 15 when the robot stops emergency because the robot interferes with an obstacle etc.
As in the case of the mode, the interlock is applied in the rotation direction of the drive motor 22, and the robot is prevented from moving in the moving direction immediately before the emergency stop, so that the robot again interferes with an obstacle or the like and damages. It will not be enlarged. Moreover, as in the case of the JOG mode, the movement amount and movement direction of each axis in the emergency stop state are indicated on the display device.
Since the display remains at 17, the operator can easily retreat the robot by operating the manual switch while looking at the display device 17, and efficiently and quickly retreat the robot. Can be.

(Effects of the Invention) As is apparent from the above description, the present invention has the following effects.

Each time the movable part of the robot is positioned, the movement amount and the movement direction of the robot axis from the start of movement to the stop of the movable part are calculated, and when a predetermined switch is turned on,
Since the calculated movement amount and movement direction of the robot axis before stopping the robot are displayed on the outside, for example, when the operator makes an emergency stop of the robot due to contact with an obstacle for some reason during operation of the robot, The operator
By turning on the switch and looking at the displayed contents, it is possible to recognize the amount and direction of movement of the robot axis necessary for retreating the robot, making it easy to retreat the robot from the emergency stop position. This can be performed efficiently and quickly, and the failure recovery time can be shortened as compared with the conventional case. Further, since the movement amount and the movement direction of the robot axis in the state of the emergency stop are displayed, these become data for elucidating the cause of the emergency stop and are useful for preventing recurrence.

In addition, when the predetermined switch is turned on, the movement of the robot axis in the movement direction before the stop is prevented. Even if a mistake is made, the robot does not contact the obstacle again, so that damage can be minimized.

Therefore, for example, when the robot stops in an emergency,
The robot can be quickly and easily evacuated by manual operation while minimizing damage.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a robot control device according to the present invention, FIG. 2 is a diagram showing a specific example of contents displayed on the display device of FIG. 1, and FIG. FIG. 4 is an explanatory diagram of a conventional robot control device. 10 ... Teach pendant, 13 ... Display request switch,
14 ... display end switch, 15 ... interlock switch, 16 ... reset switch, 17 ... display device (display means), 18 ... display control unit (calculation means, interlock control means), 19 ... 1 register, 20 ... second register (first storage means), 21 ... third register (second storage means), 22 ... drive motor, 23 ... motor control unit (motor control means), 24 ... Memory, 25 ... PG (detection means).

Continuation of front page (56) References JP-A-63-236105 (JP, A) JP-A-62-15608 (JP, A) JP-A-53-11291 (JP, A) JP-A-58-70314 (JP) , A) Tokiko Hei 2-15986 (JP, B2) Jiko 62-30082 (JP, Y2) (58) Fields investigated (Int. Cl. ⁶ , DB name) G05B 19/42-19/427 G05B 19/406-19/4063 B25J 9/22

Claims (1)

(57) [Claims] 1. A drive motor for driving a robot axis for moving a movable portion of a robot, a detecting means for detecting a current position of the robot axis, target position data set in advance and detected by the detecting means. A motor control means for controlling the drive motor based on current position data; and a robot control device for controlling the operation of the robot by controlling the drive motor by the motor control means to position the movable part. A first storage unit that stores start position data of the robot axis when the movable unit starts moving; and a second storage unit that stores stop position data of the robot axis when the movable unit stops moving. Storage means, and based on the contents of the first storage means and the second storage means, stop after the movable part starts moving. Calculating means for calculating the movement amount and moving direction of the robot axis up to, display means for displaying the content calculated by the calculating means when a predetermined switch is turned on, and a predetermined switch being turned on And an interlock control unit that outputs to the motor control unit a signal for preventing the robot axis from moving in the movement direction calculated by the calculation unit.