JPS6022212A - Robot controller - Google Patents

Abstract

PURPOSE:To set plural working robots close to each other and therefore to attain effective use of space by using a teaching box to set a movable range for each robot arm in response to the environmental conditions and the working conditions. CONSTITUTION:The upper/lower movable limit range for robot working arms is fed to a teaching box 3 by a teaching key 17. A robot is guided manually up to the upper/lower limit position, and a nonvolatile memory 9 stores the relative angle value of the robot arm from the detection value of the guided area in the form of the limit value of the movable range when the key 17 is pushed. When the robot works based on a teaching command, it is checked whether the robot arm position exceeds the range stored in the memory 9 or not. If the robot arm exceeds the fixed range, the working of the robot is stopped.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a robot control device, and more specifically, it is a robot control device that sets the minimum necessary range of movement in accordance with the conditions for using a playback type robot to ensure safety. The present invention relates to a robot control device equipped with a movable range limiting function suitable for ensuring safety.

[Background of the invention]

Conventionally, as a means to restrict the movable range of a playback type industrial robot, an end point KIJ limit switch was installed on the movable mechanism, and when the limit switch was activated, a detection signal was used to instantly control the movable part of the robot (arm). )
There is a configuration that stops the . In addition, the position of the movable parts of the robot immediately before the limit switches provided as described above are activated is calculated in advance as the relative angle value of each movable part and stored in a nonvolatile memory element, and the program Every time you calculate the target value for moving the servo and output it, check whether the relative angle of the target value is within the range of the previously memorized value, and if it exceeds that range, By forcibly stopping the mouth pot, the robot was prevented from moving beyond its specified maximum range of motion.

Therefore, when a robot is introduced into a small workplace and a small range of motion is sufficient, or when a layout arises where the robot will collide with other equipment unless the range of motion is reduced for one arm, etc.
It was not possible to change the setting of the movable range according to the conditions of use.

[Purpose of the invention]

An object of the present invention is to eliminate the above-mentioned problems and provide a robot movable range control device that can arbitrarily set the movable range of each arm of the robot according to the environmental conditions and work conditions in which the robot is installed.

[Summary of the invention]

The present invention uses a teaching box to teach the operating point position for playback of the working arm of the robot, converts the encoder value at that time into a relative angle value for each arm, and stores it in a non-volatile memory (bubble memory). Focusing on the points that had been stored in A non-volatile memory device is installed to store the data, and when the robot arm is operated, the target position is always compared in size with its movement limits, and if the upper or lower limits are exceeded, the operation is stopped. The above object has been achieved by configuring the system so that it can be carried out.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail according to the drawings. FIG. 1 shows the schematic configuration of the robot mechanism section, robot control section, and teaching box. The robot control section 1 performs various control processes according to instructions from the teaching box 3, and drives the robot mechanism section 2. 1 control. The robot control unit 1 includes a microprocessor 4. counter 6
, D/A converter7. Servo driver 8. Non-volatile memory element (magnetic bubble memory) 9, RAM10,
ROM II, serial interface 12 and pass line 4, and robot mechanism section 2 includes motor M, tachogenerator TG, and Hals encoder PE.
It consists of a parallel arm K and a working arm F.

According to the configuration shown in FIG. 1, first, a reset interrupt occurs at the same time as the power is turned on, and the program in the ROMII is activated. As a result, the system program is loaded from the non-volatile storage device 9 into the RAM 10, and after all programs have been loaded, the system jumps to a predetermined address and starts the system. All of these program processes are performed by the microprocessor 4. It periodically communicates with the teaching box 3 via the serial interface 12, and when a key on the teaching box 3 is pressed, the microprocessor 4 interprets the key contents and performs a predetermined process. Manual operation control is performed by manual operation using operating keys from the robot mechanism unit drive unit and teaching box 3, and playbank operation control is performed by inputting instructions from an operation panel installed in advance in the robot control device 1. be. The direct output from the pulse encoder PE is read by the counter 6 as the digital robot current value, and the difference between this and the value determined by the microprocessor 4 as the position target value is output to the D/A converter 7, and the motor M is driven and controlled.

The motor M is driven in this way, and the working arm F operates according to the program, but at the same time, the tacho generator T
A signal is fed back from G to the output section of the VA converter 7, and the motor rotation is monitored.

FIG. 2 shows a planar configuration of the teaching box 3 shown in FIG. 1. For simplicity, only keys relevant to the present invention will be described. In Fig. 2, 13 is a manual operation key, 14 is a mode key, 1
5id is a manual speed increment key, 16 is a manual speed decrement key, 17 is a movable range teaching key, 18 is a movable range teaching end key, and 19 is an operating point teaching key.

In the teaching box 3 with the keys arranged in this manner, the mode key 14 is used to select whether the robot moves in full joint mode or right angle mode, and the operating speed is determined by manual speed increment key 15, ff manual speed decrease This can be determined by pressing the minute key 16. After setting the speed, by pressing the manual operation key 13, the robot will continue to move as long as the key is pressed.
It stops when you release the key. At this point, the operating point teaching key 19
By pressing , the counter 6 is read and its value is written and saved in the nonvolatile storage device 9 as an operation teaching point for the play bank.

When teaching the movable range limit value, move the robot manually using the method described above to the desired position, then press the movable range teaching key 17 to light up the light emitting element LED (built into the key) on the key. . Next, by pressing the manual operation key 13 to set the conditions (2+Y key when you want to use the upper limit of the two arm axes), the microprocessor 4 reads the counter 6 and uses that value as the relative angle of each axis. The values are converted into coordinates, and only the relative angle values of the two axes are stored in the nonvolatile storage device 9 as the upper limit values of the movable range of the two axes. When you want to teach the next position, press the movable range teaching end key 18, and press the light emitting element LED of the movable range teaching key 17.
After turning off the light, the upper and lower limits of each axis can be taught by performing similar operations.

Note that the maximum and minimum limits of the robot mechanism are input as initial values into the non-volatile memory that stores the movement limits, so the robot operator (user) can store them without having to teach the movement range. When the robot is moved, the range of motion specified is obtained. - Figure 3 is a 70-chart showing the process flow of teaching the movable range limit position added to the teaching program and operating the robot only within the taught range.
The figure is a flowchart showing the flow of processing for causing the robot to operate only within the taught range during playback.

The contents of the present invention will be specifically described below in accordance with the 70-charts in FIGS. 3 and 4, and its effects will be clarified. The teaching processing program is a task program that is started when it is necessary to control and process the robot based on key manual instructions from the teaching box 3, and is mainly used for the purpose of teaching operating points for performing playback operations. , mode key 14 manual speed increment key 15 ,
After selecting and setting the manual speed decrement key 16, keep pressing the manual operation key 13 to guide the robot to a predetermined position, and press the operation point teaching key 19 to store and store the operation point data in the nonvolatile storage device 9. .

This state corresponds to the case where the LED of the movable range key in Figure 83 is lit, the operation key number, upper and lower limit reading 21, encoder lead n, coordinate transformation n5, and the movable limit value storage is not available. The limit values to be compared with 5 within the movable limit value are the maximum and minimum values of the specifications stored in advance in the storage device and are unchangeable.

In the embodiment of the present invention, the teaching box 3 newly includes a movable range teaching key 17 and a movable range teaching end key 1.
For example, the manual operation key 13
Continue to press , and the teaching box key manual interpretation process in Figure 3 will display whether the operation key is on, whether the n1 movable range key LED is lit, operation mode field, joint target value calculation process 29, and whether the movement limit value is within 5. After repeating the process and guiding the robot, by pressing the movable range teaching key 17 and lighting up the light emitting element LED built in the movable range teaching key 17, 70-chart addition, 21 in FIG. ,22,
23 and 30 are performed. That is, the manual operation key 13 pressed while the light emitting element LED of the movable range teaching key 17 is turned on is 12 from 1-X to 6+α.
The microprocessor 4 in FIG.
The operation key number, the contents of the upper and lower limit procedure 21, and the contents of the encoder PE shown in Fig. 3 are read by the counter 6 (encoder read 22), and from the values, the relative angle of the robot's 6 arms is calculated. Calculate the value using the coordinate transformation formula (3rd
Coordinate transformation of figure 23). Then, after selecting only the approximate relative angle value of the arm from the values previously stored in the RAM 10 and deciding whether to set the upper limit value or the lower limit value, the relative angle value is stored in the non-volatile storage device 9. (the movable limit value storage 30 in FIG. 3).

Then, by pressing the movable range teaching end key 18 in FIG. 2, the light emitting element LED of the movable range teaching key 17 goes out, and conventional manual operation becomes possible, so the robot is guided to another position again. Furthermore, the range of motion limits for other arms can be taught using the method described above. In addition, since the movable range limit value to be compared and determined is stored in the non-volatile storage device 9 after being taught above, let's control the robot after the teaching is done. When the relative angle conversion value of the target value exceeds the upper and lower limits, servo stop processing is performed, making it impossible to move outside the movable range.

Although it is possible to reteach the movable range limit value outside the movable range once set, the method for doing so is omitted because it is not directly related to the present invention.

Next, the playback operation will be explained according to FIG. 4. The playback process is almost the same as the conventional one, but only within the movable limit value 31 is interpolated with the data stored in the non-volatile storage device 9 as previously explained in the movable range teaching method, similar to the teaching process. The relative angle value of the target value calculation result (joint target value calculation 32. coordinate transformation 33) is compared and judged, and if the taught upper and lower limit values are exceeded, servo stop processing is performed and playback control is interrupted. It is something.

According to the embodiment described above, there are the following advantages.

In other words, if the robot is installed in a small space and moves within the specified maximum range of motion, it will collide with other equipment, but in reality, the robot cannot be used even though it can be used within a small range of motion. The problem is that the playback work areas of the robots on the stand should be placed close together so that they do not interfere with each other, but if the robots move beyond the specified movable range due to out of control, they will collide, so they have to be placed widely. can be solved.

Therefore, it is possible to teach and set the minimum range of movement required each time according to the working conditions in which the robot is used, and it is safe because the robot does not run out of control and collide with other nearby equipment or workers. There are advantages such as the ability to place robots in close proximity to each other.

〔Effect of the invention〕

As is clear from the above-described embodiments, according to the present invention, a user who purchases and uses a robot can use a teaching box to teach the range of movement of the six arms of the robot according to the environmental conditions in which the robot is installed, and the work conditions. Because it can be set, there is no risk of the robot arm colliding with other nearby equipment or workers, which not only improves safety, but also improves work space efficiency by allowing multiple robots to work in close proximity. There are advantages and effects such as being able to achieve the same goals.

[Brief explanation of drawings]

FIG. 1 is a hardware configuration diagram of a robot showing an embodiment of the present invention, FIG. 2 is a plan view showing a partial external appearance of FIG. 1, and FIG. FIG. 4 is a flowchart for explaining the teaching method of the present invention which includes a teaching step for moving the robot within the taught range of motion; FIG. It is a flowchart explaining a process. 1... Robot control device, 2... Robot mechanism section,
3... Teaching box, 4... Microprocessor 1.5... Pass line, 6... Counter, 7
... D/A converter, 8... Servo driver, 9.
・・Nonvolatile storage device (magnetic bubble memory), 10・・
・RAM, 11...ROM, 12...IJ full interface, 13...Manual operation key,
14...Mode key, 15...Manual speed increment key, 16...i manual speed decrement key, 17...
Movable range teaching key, 18... Movable range teaching end key,
19... Operating point teaching key. Agent Patent Attorney Masami Akimoto

Claims (1)

[Claims] In a robot control device comprising a robot control device for driving and controlling the robot according to a program and a teaching box for teaching and setting the operating point of the robot, the teaching box is configured to set the upper and lower limits of the movable range of the robot working arm. In addition to providing a teaching key for inputting teaching, when the robot is guided to the upper and lower limit positions by manual operation and the teaching key is pressed, the relative angle value of the robot working arm is moved from the detected guided position value. A non-volatile storage device that stores range constraint values, and whether or not the working arm position of the robot exceeds the range of the stored value of the non-volatile storage device that is stored in advance when the robot operates based on a teaching command. A robot control device characterized in that it is provided with a control means for checking and stopping the operation of the robot if it is exceeded.