JPH03250305A - Robot controller - Google Patents

Abstract

PURPOSE:To side a robot from an emergency stop position with high efficiency by attaining such a constitution where the moved variable and the moving direction of a mobile member are displayed on a display means when a display request switch is turned on. CONSTITUTION:A storage means 20 is provided to store the movement start position of a mobile member together with a storage means 21 which stores the present position where the mobile member stops its movement, a motor control means 23 which calculates the moved variable of the mobile member obtained from its start through its stop based on the stored position and at the same time deciding the moving direction of the mobile member to control a drive motor 22 so that the mobile member is prevented from moving in its moving direction, and a display means 17 which displays the moved variable and the moving direction of the mobile member outputted from the means 23. If a robot touches an obstacle, etc., and an operator stops urgently the mobile member, for example, a display request switch 13 is turned on for display of both the moved variable and the moving direction of the robot. Thus the operator can recognize the moved variable and the moving direction of the mobile member which are necessary for the siding of the robot. Then the robot saving job efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention can be used to quickly stop the robot while minimizing damage, for example, when the robot interferes with an obstacle and has to make an emergency stop during robot teaching. The present invention relates to a robot control device that can easily avoid robots.

(Conventional technology) With the advancement of automation technology in recent years, various production factories, etc.
A wide variety of robots are used.

- Shooting robots require a so-called "teaching" operation in which work movements are taught in advance, and conventionally, this teaching has sometimes been carried out as shown in FIG. 4.

A robot 1 shown in the figure is a so-called multi-jointed robot, with two main shafts. Arm 3. The so-called 6 drive motor which drives the 8 types of movable members of the hand 4 by 6 drive motors (not shown)
It is an axis robot. The operation of this robot 1 is controlled by a control device 5 that performs so-called feedback control of these drive motors, and as shown in the figure, an operator can receive information regarding the operation of the robot 1. A teach pedant (hereinafter simply referred to as a pendant) 6 for inputting is connected.

This pendant 6 is equipped with a switch for individually driving each drive motor, a switch for storing the position of the movable member determined by the switch, and the like. The pendant 6 also has a JO that allows the operator to operate the drive motor individually as described above.
G mode and robot 1 according to the memorized movements.
A mode switch is provided to switch between a playback mode (hereinafter simply referred to as PB momo) in which the robot 1 automatically operates the robot 1, and the operator can check the motion of the robot 1 taught in the JOG mode using the PB mode. is now possible. By operating these switches, the operator can perform teaching work and have the robot 1 perform a desired work operation.

However, during such conventional teaching work, if the operator makes a mistake in operating the pendant 6 in JOG mode, the robot 1 may come into contact with an obstacle such as another production equipment, or the robot 1 may Because robot 1 did not take into account obstacles in its travel route, robot 1 sometimes came into contact with obstacles when it was operated automatically in PB mode. Conventionally, in these cases, robot 1
The robot 1 is brought to an emergency stop, and while the operator observes the movement of the robot 1 in JOG mode, the robot 1 is evacuated from the position where the interference occurred, that is, the position where the emergency stop was made.

For this reason, the conventional robot 1 has a system that indicates the moving direction of each movable member according to the rotational direction of the drive motor so that the moving direction of each movable member can be determined at a glance as shown in the figure. Marker 7 is attached. This allows the operator to control robot 1. The direction of movement for evacuation is determined according to the emergency stop state of the robot, and evacuation work of the robot is performed.

(Problem to be solved by the invention) However, even when the robot is evacuated by relying on the marker, the operator may make a mistake in operating the pendant, causing the robot to come into contact with the obstacle again, resulting in damage. was sometimes enlarged.

In addition, especially in the case of a multi-axis robot as shown in Fig. 4, the movement of the robot is formed by combining the movements of a large number of movable members, so the movement of each movable member in order to evacuate the robot is necessary. The system was complicated, and it took time for the operator to manually evacuate the robot, resulting in inefficiency.

The present invention has been made to solve these conventional problems, and is capable of quickly evacuating the robot while minimizing damage when the robot comes into contact with an obstacle and makes an emergency stop. The purpose of the present invention is to provide a control device for a robot that can be easily controlled.

(Means for Solving the Problems) In order to achieve the above object, the present invention includes a drive motor that drives various movable members of the robot and a detection means that detects the current position of the movable members, and In a robot control device that controls the operation of a robot by controlling a drive motor based on target position data of a movable member and a current position detected by a detection means and positioning the movable member, at least the robot can perform an emergency stop. a display request switch and an interlock switch that are turned on when the movable member starts moving; a first storage means that stores the starting position when the movable member starts moving; and a first storage means that stores the current position when the movable member stops moving. a second storage means for storing; and a second storage means for storing the first
Based on the starting position stored in the storage means and the current position stored in the second storage means, the amount of movement of the movable member from when it starts to when it stops is calculated, and the direction of movement is determined by 'I'. '11 Disconnect and turn on the display request switch
outputs the moving table and the moving direction when the moving table is moved,
a control means for controlling the drive motor so as to prevent the movable member from moving in the movement direction when the lock switch is turned on; and the amount of movement and the movement output by the control means. The present invention is characterized in that it has a display means for displaying the direction.

(Function) The present invention configured as described above functions as follows.

For example, when the robot comes into contact with an obstacle or the like for some reason during operation and the operator brings the robot to an emergency stop, the display request switch is turned on and the control means is stored in the first storage means. The movable platform and the moving direction determined based on the starting position and the current position stored in the second storage means are output. Then, the display means displays the amount and direction of movement of these items, so the operator can see the amount and direction of movement of the movable part H required to evacuate the robot. The robot can be efficiently evacuated from the stopped position.

Furthermore, by turning on the interlock switch when the operator or the robot makes an emergency stop, the control means prevents the movable member from moving in the direction of movement immediately before the emergency stop, based on the determined movement direction. Control the drive motor as follows. As a result, even if the operator makes a mistake when manually evacuating the robot, the robot will not come into contact with an obstacle again, so damage can be kept to a minimum. Become.

Therefore, when the robot makes an emergency stop, it becomes easy to quickly evacuate the robot while minimizing damage.

(Example) Below, a robot control device according to the present invention will be explained in detail based on the drawings.

FIG. 1 is a schematic configuration diagram 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 shown in FIG. 1.

Further, FIG. 3 is a flowchart showing the operation of the robot control device according to the present invention. The robot control device described here controls the operation of a 6-axis robot similar to the conventional one, but since the control for each drive motor is the same, here we will explain the control for one drive motor. The contents will be explained, and the explanation of the control of other drive motors will be omitted.

As shown in FIG. 1, the robot control device according to the present invention is equipped with a teach pendant (hereinafter simply referred to as a pendant) 10 that is operated by an operator when performing teaching work, similar to a conventional teach pendant. ing.

This pendant 10 includes a JOG pendant as well as the conventional one.
A mote switch that switches between mode and PB mode,
The operation switch 11 is composed of a manual switch for manually operating each drive motor in the OG mode, a memory switch for memorizing the position when the movable member is positioned by this switch, and the like. An emergency stop switch 12 is installed to bring the robot to an emergency stop when there is an abnormality in operation or when the robot comes into contact with other equipment (i'i equipment, etc.).

In addition, the pendant 10 has a display request that is turned on to display the amount and direction of movement of each movable member immediately before the robot stops, such as when the robot is brought to an emergency stop using the emergency stop switch 12. switch 13, and a display end switch 14 that is turned on to end this display.
is installed.

Furthermore, the pendant 10 has an emergency stop switch 12 that is similarly turned on, and an interface that is turned on when the robot is brought to an emergency stop to prevent each movable member from moving in the movement direction immediately before the emergency stop. A lock switch 15 and a reset switch 16, which is turned on when ending this control, are installed.

Furthermore, in addition to these switches, the pendant 10 is provided with a display device 17 that displays the amount and direction of movement of each movable member when the display request switch 13 is turned on. 10 is a display control unit 1
8 is connected.

The display control unit 18 is configured to obtain the movement amount and movement direction of the movable member to be displayed on the display device 17, and the display control unit 18 includes a Lujister 19. A second register 20 as the first storage means and a third register 21 as the second storage means are connected to each other.

Further, the display control section 18 is connected to a motor control section 23 that outputs data for calculating the moving teeth to these registers.

The operating states of the operation switch 11 and the emergency stop switch 12 of the pendant 10 are input to this motor control unit 23, and the motor control unit 23 inputs the operating states of these switches as in the past. Accordingly, the drive motor 22 that drives movable members such as the robot's arm, main shaft, and /'% hand is controlled.

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

This target position data includes the movement tEJ target position of the movable member,
That is, the data corresponds to the target rotation angle of the drive motor 22, and is sequentially set by an operator or the pendant 10 operating the operation switch 11 in the JOG mode to perform a teaching operation, as in the past.

Further, a pulse generator (hereinafter referred to as PG) 25 for detecting the rotation angle of the drive motor 22 is connected to the motor control section 23 .

The PG 25 outputs a pulse signal corresponding to the rotation of the main shaft of the drive motor 22, and the motor control unit 23 can detect the rotation angle of the drive motor 22 by counting this pulse signal. It is now possible to do so.

Then, when the mode changeover switch of the operation switch 11 has set the PB mode, the motor control unit 23 manually inputs the target position data sequentially from the memory 24 and selects the PG mode.
A drive signal is output to drive the drive motor 22 until the rotation angle detected by the drive motor 25 matches the input target position data. Then, the signal form of this drive signal is converted by the D/A converter 26 and amplified by the amplifier 27 to become drive power, which is supplied to the drive motor 22. Thereby, the motor control unit 23 can drive the drive motor 22 according to the input target position data. In other words, the motor control unit 23 performs so-called feedback control on the drive motor 22 using the PG 25, and can sequentially drive the drive motor 22 according to the target position data set in the memory 24, thereby causing the movable member to move as taught. It is now possible to operate it.

Further, when the motor control unit 23 is set to JOG mode by the mode changeover switch of the operation switch 11, the operator turns on the manual switch of the operation switch 11.
While in L, a drive signal is output 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 drives the drive motor 22 corresponding to the manual switch operated by the operator only while the manual switch is turned on.
Each movable member can be positioned arbitrarily.

Then, in the JOG mode, when the operator releases the manual switch and stops the drive motor 22, the motor control unit 23 that controls the drive motor 22 controls the newly positioned current position. The rotation angle (hereinafter referred to as the current rotation angle) is detected by the PG 25, and this 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 when the movable member stops moving. After this, a positioning completion signal indicating that the movable member has stopped and been positioned is displayed and output to the control unit 18.

Further, the motor control unit 23 controls PG2 in the PB mode.
When the rotation angle of the drive motor 22 detected in step 5 matches the target position data input from the memory 24 and the drive motor 22 is stopped, the input target position data,
That is, the target position data input for current positioning (hereinafter referred to as current target position data) is output to the first register 19. After this, a positioning completion signal indicating that the movable member has stopped and been positioned is output to the display control section 18.

Furthermore, when the emergency stop switch 12 is turned on and the drive motor 22 is brought to an emergency stop, the motor control unit 23
The current rotation angle in the emergency stop state is detected by the PG 25, and this current rotation ((1 degree) is output to the third register 21. Then, after this, an emergency stop signal indicating that the emergency stop has occurred is output to the display control unit 18. It is designed to output to .

In the JOG mode, the display control unit 18 that manually inputs these signals from the motor control unit 23 displays the signals while the positioning completion signal is not output, that is, the positioning is not completed and the movable member is moving. Then, the rotation angle at the time of previous positioning (hereinafter referred to as the previous rotation angle), which is already stored in the third register 21, is stored in the second register 2.
It is designed to be stored in o. That is, the display control unit 18 causes the second register 20 to store the pre-rotation angle corresponding to the start position when the movable member starts moving. When the display control unit 18 receives the positioning completion signal from the motor control unit 23, it inputs the current rotation angle newly output to the third register 21, and stores the current rotation angle in the second register 20 from this current rotation angle. The amount of movement from the previously positioned position, that is, the amount of movement of the movable member, is calculated by subtracting the previous rotation angle.

Further, the display control unit 18 determines that if the current rotation angle increases from the previous rotation angle, the movement direction is (10), and if the current rotation angle decreases, the movement direction is (-). to decide.

In addition, in the PB mode, the display control unit 18 also outputs a signal that was input when the motor control unit 23 performed previous positioning and has already been stored in the Lujistar 19 while the movable member is moving to which no positioning completion signal has been output. The target position data (hereinafter referred to as previous target position data) that has been set 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 when the movable member starts moving.

When the display control unit 18 receives the positioning completion signal from the motor control unit 23, it inputs the current target position data newly output to the Lujistar 19, and stores the current target position data in the second register 20. The previous target position data is subtracted to calculate the amount of movement from the previously positioned position, that is, the amount of movement of the movable member.

Furthermore, as a result, the display control unit 18 determines that when the current target position data increases from the previous target position data, the moving direction is (+), and when the current target position data decreases, the moving direction is (-). I judge that there is.

In addition, when the emergency stop signal is input manually in the PB mode, the display control unit 18 inputs the current rotation angle that the motor control unit 23 outputs to the third register 21, and inputs the current rotation angle into the second register 20 from this current rotation angle. The previously stored target position data is subtracted to calculate the amount of movement from the previously positioned position to the emergency stop position. Further, the display control unit 18 thereby determines the moving direction of the movable member immediately before the emergency stop, similarly to the above. In addition, in JOG mode,
In the event of an emergency stop, the operator or manual switch should be turned OFF.
FF, the positioning completion signal is output from the motor control unit 23 to the display control unit 18, and the display control unit 18 calculates the amount of movement and direction of movement from the previously positioned position to the emergency stop position. It will be done.

Then, when the display request switch 13 of the pendant 10 is turned on, the display control unit 18 calculates the amount of movement calculated in each mode and the direction of movement determined at the same time.
The image is displayed on the display device 17 as shown in FIG. 2 until the display end switch is turned on. At this time, the display control unit 18 causes the maximum value of the movement amount calculated for each movable member to blink as shown in FIG. 2.

Therefore, when the operator makes an emergency stop of the robot and turns on the display request switch 13, the amount and direction of movement from the previously positioned position to the emergency stop position will be displayed on the display device 17. The operator is
The amount and direction of movement of each movable member for evacuating the robot can be recognized, making manual operation for evacuating the robot easier. Also, the display request switch 13 is turned on.
Then, the amount and direction of movement of the movable member are displayed on the display device 17 according to the robot's motion in each mode, so the operator can see the robot's motion during the motion.

Furthermore, when the interlock switch 15 of the pendant 10 is turned on, the display control section 18 controls the motor control section 2.
3, an interlock double voltage is output.

The motor control unit 23 that manually performs this interlock doubler performs a so-called interlock in which the drive motor 22 is not rotated in the rotation direction immediately before inputting this interlock signal.

As a result, if the operator turns on the interlock switch 15 when the robot makes an emergency stop, the movable members will not move in the direction of movement immediately before the emergency stop, so the operator can manually evacuate the robot. If this is done, even if the robot makes a mistake in operation, the robot will not come into contact with an obstacle or the like again and cause further damage. Further, the operator manually drives the drive motors 22 corresponding to the flashing movement amounts in order, and moves m.
By driving the drive motors 22 in the order of the number of robots, the robot can be efficiently evacuated.

The robot control device of the present invention configured as described above operates based on the flowchart shown in FIG. The motor control section 23 drives and controls the motor 22 when the operation switch 11 and the emergency stop switch 12 are turned on, as this is the same as that of a conventional general robot control device. A description of its operation will be omitted.

First, the display control unit 18 inputs the operating state of the mode changeover switch among the operation switches 11, and determines whether the current mode is the JOG mode (step 1).

If the current mode is the JOG mode, the display control unit 18 waits until the positioning completion signal is not output, that is, the movable member is moving (step 2).
During movement, data transfer is performed to store the previous rotation angle stored in the third register 21 in the second register 20 (step 3).

Then, the display control unit 18 waits until the motor control unit 23 outputs a positioning completion signal (step 4).
When it is determined that the positioning of the movable member is completed by manually inputting a positioning completion signal, the current rotation angle outputted by the motor control unit 23 to the third register 21 is manually input, and the current rotation angle is stored in the second register 20. The amount of movement of the movable member is calculated by subtracting the previous rotation angle. At the same time, the display control unit 18
By this subtraction, the direction of the moving force of the movable member is determined as described above (step 5).

Next, the display control unit 18 turns on the display request switch 13.
It is determined whether the flag n in the internal memory that stores the fact that the process has been performed is set to 1, and if the flag n is already set to 1, the process proceeds to step 9 (step 6). On the other hand, if the flag n is not 1, the display request switch 13 is turned off.
It is determined whether display of the amount of movement and direction of movement is requested, and if it is not requested, the step unit 0 is
If the request has been made, 1 is assigned to the flag n, and the fact that the display request switch 13 has been turned on is stored (step 7.8).

Then, the display control unit 18 outputs the obtained movement amount and movement direction to the display device 17, and displays them on the display device 17 (step 9).

Next, the display control unit 18 controls the interlock switch 15
It is determined whether or not the interlock switch 15 is turned on (step 10). If the interlock switch 15 is not turned on, the process proceeds to step 13; if it is turned on, an interlock signal is output to the motor control section 23, The drive motor 22 is interlocked to prevent the movable member from moving in the determined movement direction (step 11).

Then, the display control unit 18 determines that the reset switch 16 is turned off.
Until N is reached, return to step 6, continue interlocking the drive motor 22, and turn on the reset switch 16.
When this occurs, the output of the interlock signal is stopped and the interlock of the drive motor 22 is released (step 12).

Next, the display control unit 18 turns on the display end switch 14.
In step 13), the display termination switch 14 is turned on and the flag n is set to 1 until a request is made to terminate the display of the amount of movement and direction of movement. Leave the display end switch 14
When turned on, 0 is assigned to flag n and the above operation is repeated. (Step 14).

On the other hand, in step 1, if the current mode is not the JOG mode, the display control unit 18 determines whether the current mode is the PB mode. Wait (step 15).

When the display control unit 18 is in the PB mode, the display control unit 18 waits until the positioning completion signal is not output, that is, the movable member is moving (Step 16), and when the movable member is moving, the Data transfer is performed to store the previously stored target position data in the second register 20 (step 17).

Further, the display control section 18 waits until a positioning completion signal or an emergency stop signal is output from the motor control section 23 (step 18.19).

Then, when the positioning completion signal is manually input, the display control unit 18 determines that the positioning of the movable part has been completed,
The current target position data outputted by the motor control unit 23 to the first register 19 is manually input, and the previous target position data stored in the second register 20 is subtracted from the current target position data to calculate the amount of movement of the movable member. At the same time, display control unit 1
8 determines the moving direction of the movable member by this subtraction as described above, proceeds to step 6, and displays these when the display request switch 13 is turned on as described above (step 20).

On the other hand, if an emergency stop signal is input, the display control unit 18 determines that the robot has made an emergency stop during automatic operation in the PB mode and proceeds to step 5, where the motor control unit 23 focuses on the third register 21. The current rotation angle is input, and the previous target position data stored in the second register 20 is subtracted from this current rotation angle to calculate the amount of movement of the movable member from the previously positioned position to the emergency stop. at the same time,
The display control unit 18 determines the moving direction of the movable member immediately before the emergency stop based on this subtraction, and displays these moving amounts and moving directions on the display device 17 when the display request switch 13 is turned on as described above. let

In the JOG mode, when the operator turns on the display request switch 13, the amount and direction of movement are displayed on the display device 17 each time the operator operates the manual switch to manually position the movable member. Ru. For example, if the operator makes a mistake in operating the manual switch and the robot interferes with an obstacle, causing an emergency stop, turning on the interlock switch 15 will
Since the drive motor 22 prevents the movable member from moving in the direction of movement immediately before the movable member makes an emergency stop, damage caused by interference with an obstacle will not be magnified. Moreover,
Since the amount and direction of movement of the movable member in this emergency stop state remain displayed on the display device 17, the operator cannot evacuate the robot by operating the manual switch while looking at the display device 17. This makes it easy to evacuate the robot efficiently.

Also in the PB mode, when the operator turns on the display request switch 13, the amount of movement, movement, and direction are displayed on the display device 17 each time the motor control unit 23 automatically positions the movable member. For example, if the robot interferes with an obstacle or the like due to a teaching error and makes an emergency stop, if the operator turns on the interlock switch 15, the robot will be stopped in the same way as in the JOG mode.
Since the drive motor 22 prevents the movable member from moving in the direction of movement immediately before the movable member makes an emergency stop, damage caused by interference with an obstacle will not be magnified. Similarly, since the amount and direction of movement of the movable member in this emergency stopped state remain displayed on the display device 17,
The operator can efficiently evacuate the robot by operating the manual switch while looking at the display device 17.

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

When the display request switch is turned on, the control means calculates the movement amount and movement direction of the movable member based on the starting position stored in the first storage means and the current position stored in the second storage means. Since the information is displayed on the display means, for example, if the robot comes into contact with an obstacle or the like for some reason during operation and the operator brings the robot to an emergency stop, the operator can check the display request switch or ONL and the display means. This allows the robot to recognize the amount and direction of movement of the movable parts required to evacuate the robot, efficiently evacuating the robot from the emergency stop position, and shortens failure recovery time compared to conventional methods. I can do it. Furthermore, since the amount and direction of movement of each movable member in the state of emergency stop are displayed, these serve as data for elucidating the cause of emergency stop, and are useful for preventing recurrence.

Furthermore, by turning on the interlock switch when the operator brings the robot to an emergency stop, the control means prevents the movable member from moving in the direction of movement immediately before the emergency stop, based on the determined movement direction. Since the drive motor is controlled in this manner, when the operator manually evacuates the robot in the above case, even if the operator makes a mistake, the robot will not come into contact with an obstacle again. Therefore, damage can be kept to a minimum.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a control device for a robot according to the present invention, FIG. 2 is a diagram showing a specific example of content displayed on the display device shown in FIG. 1, and FIG. 3 is a diagram showing a robot according to the present invention. FIG. 4 is an explanatory diagram of the conventional robot control device. 0...Teach pendant, 13...Display request switch, 14...Display end switch, 15...Interlock switch, 16...Reset switch, 1
7...Display device (display means), 18...Display control section (control means), 19...Second register, 20...Second register (first storage means), 21...No. 3 register (second storage means), 22... drive motor, 23...
Motor control unit (detection means, control means), 24...memory, 25...PG (detection means).

Claims (1)

[Claims] The robot is equipped with a drive motor that drives various movable members of the robot and a detection means that detects the current position of the movable member, and the drive motor is operated based on preset target position data of the movable member and the current position detected by the detection means. A robot control device that controls the operation of a robot by controlling and positioning a movable member includes at least a display request switch and an interlock switch that are turned on when the robot makes an emergency stop, and a display request switch and an interlock switch that are turned on when the robot makes an emergency stop; a first storage means for storing the start position when the movable member stops moving; a second storage means for storing the current position when the movable member stops moving; and a first storage means for storing the current position when the movable member stops moving; The amount of movement of the movable member from when it starts moving until it stops is calculated based on the current position stored in the second storage means, and the direction of movement is determined, and the display request switch is turned on. a control means that outputs the amount of movement and the direction of movement, and controls the drive motor so as to prevent the movable member from moving in the movement direction when the interlock switch is turned on; A robot control device comprising: display means for displaying the movement amount and movement direction output by the control means.