JPS5834793A - Controller for arm of robot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a robot arm control device that causes an arm to work within a certain area.

Generally, the working area of a robot's arm is within the maximum movable range, but if the robot's arm runs away or goes out of control for some reason, it will operate to the end of its maximum movable range, posing a danger to a person or the surrounding area. There was a risk of destroying the device. Therefore, in order to eliminate the above-mentioned risks.

A regulation area called an emergency area may be provided outside the work area, and the robot arm may be brought to an emergency stop when this area is reached. The work area here refers to the area where the arm performs work within the range taught to the robot, and the emergency area is the area beyond which movement of the arm would pose danger or damage to the human body or peripheral equipment. Yes, it is determined by the surrounding environment at the workplace where the robot is installed.

In conventional teach-and-play robots, the operator determines the work area by teaching the necessary work from a teaching box and then teaching the work directly by picking up the robot arm. You can enter the emergent region using

However, if the emergence area set outside the 9 working area is a complicated curve, it is very difficult to input the emergence area from the teaching box, and the manual teaching method cannot handle complicated curves. However, if the robot itself is large and heavy, manual teaching by an operator is nearly impossible.

Therefore, the object of the present invention is to provide a control area called an emergency area outside the work area to ensure the safety of surrounding workers and peripheral equipment, and to provide a robot arm control device that can easily input and force the emergency area itself. is to provide.

In order to achieve the above object, the robot arm control device of the present invention imitates a reduced template similar to the region that regulates the movable range of the arm, that is, the emergence region, and a reduced region similar to the regulating region of this template. It is equipped with a feeler and means for storing a restricted area obtained by tracing the feeler, and compares the position detection signal of the arm position detection device with the position signal of the restricted area stored in the storage means, and determines that the arm position is within the restricted area. When it reaches.

The drive of the arm is stopped.

The present invention will be described in detail below with reference to an embodiment shown in one drawing.

FIG. 1 is a diagram schematically showing an embodiment of the present invention. In FIG. 1, 1 is the robot body.

2 is a first arm, 3 is a second arm, and these first arms 2. A predetermined work is performed by driving the second arm 3. Also, a is the maximum movable range of the arm mechanical system, pb is an emergency range set within the maximum movable range, and C is a work range in which the arm is normally driven and controlled. 4
Reference numeral 5 denotes a template on which a reduced figure d similar to the emergent area is formed, and 5 is a feeler of the copying device B. By copying the reduced figure d with this filler 5, a copying signal is obtained. The scanning signal is sent to the robot control device 8 via a signal line 7, converted into an actual size value, and stored as an emergency area signal. The robot control device 8 is connected to the signal line 9.

A control signal is sent to the robot 1 to drive and control the first arm 2 and the second arm 3. Further, the robot control device 8 is an arm position detection device (not shown) provided in the robot 1.
The position of the first arm 2 is θ1°, and the position of the second arm B is θ2.
is compared with the stored emergency and emergency area signals, and if the arm exceeds the emergency area, the driving of the first arm 2 and the second arm roller is stopped.

FIG. 2 shows a control system block diagram used in the embodiment shown in FIG. In the figure, 11 is a CPU, which executes necessary calculations and control processing according to a program stored in a program memory 12. 13 is a memory for storing the emergency boundary signal obtained by the feeler 5 of the copying device 6; 14 is the first arm 2. A memory 15 is a console switch that stores the operating points caused by the drive of the second arm B. Furthermore, 20 is the first arm 2
That is, it is a θ1-axis driver, and is a D/A converter 21. Servo amplifier 22. It is composed of a motor 23 and a position detector 24. The control signal from cPUll passes through the path line 16 and is connected to the D/A (D/A).
The D/A converter 21 converts the control digital signal into an analog signal, which is applied to the servo amplifier 22. The motor 25 is rotated in accordance with the analog amount, and the first arm 2 is rotated by 01 times. This rotated position θ1 of the first arm 2 is detected by the position detector 24 and stored in the operation point memory 14 via the path line 16. 3o is a driver for the second y-mus-9, that is, the θ2 axis.

Same configuration as the θ1 driver, that is, D/A converter 3
1. Servo amplifier 22. It has a motor 331 and a position detector 54. 4o is a feeler, which is a θ′ 1-axis position detector 41. It is equipped with a θ′2-axis position detector 42, and the θ′1. θ'2 is obtained and stored in the emergence boundary memory 13. Note that 43 is a power switch, and 44 is a rectifier. The rectified voltage of the rectifier 44 is θ as the power supply voltage.
It is supplied to the 1-axis driver 20 and the θ 2-axis driver 3o.

Next, the operation of the circuit block shown in FIG. 2 will be explained separately for the emergency setting and for one work operation.

FIG. 13 shows the control flow at the time of emergency setting in FIG. 2. These control flows are stored as programs in the program memory 12, and are executed by the CPU.
Processing is executed under control 0 of 11.

In FIG. 6, the operation starts when the emergency switch of the console is turned on. First, in step ST1, new data θ'1 and θ'2 are obtained from the θ'1 position detector 41°θ'λ position detector 42 of the filler 40. Furthermore, in step ST2, θ'1 and θ'2 are set to the actual size θ1 and θ2.
Convert to Then, in step ST3, θ71·θi are stored in the emergency boundary memory 13. Then θ′1
- Determine whether θ'2 has changed using Si2. If there is no change, the determination is No, and in step ST5 it is determined whether the emergency switch is turned off. Emergency S
If W is OFF, copying is finished and the operation ends, but it is determined that the emergence SW is still ON.
At 0, it returns to Si2, and the feeler 5 in Fig. 1 moves, and θ'1
・Step ST4. until θ2 changes. Stay in ST5. Feeler 5 moves and imitators are excited Ruto, step 7”
The determination of Si2 is YES, and the operation flow is step STi.
Returning to the previous step, the operations from step STi to step ST4 are repeated in the same manner as described above. Then, new values θ"1 and θ"2 are sequentially stored in the emergent boundary memory 16 as the transition progresses.

FIG. 4 shows the control flow during the work operation in FIG. 2. Normally, at step ST6 when the operation starts, new data θ1 and θ2 are read from the operation point memory 14 and output to the θ1-axis driver 20 and the θ2-axis driver 60 to respectively drive the first arm 2 and second arm 6 of the robot. do. Then, in step ST7, the output of the position detector 14 for the θ1 axis is read, and further in step ST8, the θ
The pair θ2 with θ1 corresponding to 1 is read from the emergency boundary memory 13'. Note that if there is no θ''1 that matches θ1, θ''1 of values before and after it may be used.Next, in step ST9, it is determined whether θ2=02.The movement of the second arm 3 is still in the emergent region. If within, the judgment is No, and the process returns to step ST6 to move on to the next new motion point. However, if the movement of the second arm B crosses the emergence region, at least θ2=θ″2 There is a point in time when
The determination in step 5 is YES, and the process moves to step 5TiQ to perform a merge process, that is, turn off the power switch 43 in FIG. 2, and end the operation.

Although the above embodiments have been described with respect to operations on a two-dimensional plane, it goes without saying that the present invention can also be applied to a three-dimensional space.

As described above, according to the present invention, there is a reduced template similar to the region that regulates the range of movement of the arm, a feeler that copies the reduced region that is similar to the regulating region of this template, and a template that is obtained by copying the feeler. Equipped with a means to memorize the regulated area.

The driving arm position is compared with the position signal of the regulated area stored in the storage means, and when the arm position reaches the regulated area, the drive of the arm is stopped. It is possible to ensure the safety of a single person and peripheral devices without getting close to them. Furthermore, since the regulated area is input by copying a reduced template similar to the regulated area using a feeler, the regulated area itself can be inputted relatively easily.

[Brief explanation of drawings]

41 is a diagram showing an outline of an embodiment of the present invention, FIG. 2 is a block diagram showing a control system used in the embodiment of FIG. 1, and FIG. 3 is a control during emergency setting in the block diagram of FIG. 2. FIG. 4 is a diagram showing the control flow during the work operation in the block diagram of FIG. 2. 1: Robot, 2: First arm, 3: Second arm,
4: Template, 5: Feeler. 6: Copying device, 7/9: Signal line, 8: Robot control device, 11: CPU, 12 Niprogram memory, 13: Emergency boundary memory e 14: Operation point memory. 20: θ 1-axis driver, 21/31: D/A converter, 22/'52: Servo amplifier. 26/35: Motor, 24/54: Position detector,
50: θ 2-axis driver, 40: Feeler device, 4
1: 01-axis position detector, 42: θ2-axis position detector, 4
3: Power switch. 44: Rectifier. Patent Applicant Tateishi Electric Co., Ltd. Agent Patent Attorney Shigeru Nakamura Magnification 2 Hidai 3 Figure 4

Claims (1)

Claims: An arm control device for a robot that includes a device for detecting the position of an arm and controls the arm position based on a position detection signal from the arm position detection device. A reduced template similar to a region regulating the range of movement of the arm, a feeler that imitates a reduced region similar to the regulating region of this template, and means for storing the regulating region obtained by the feeler's companion. . A robot arm control device, characterized in that the position detection signal of the arm position detection device is compared with a restriction area of the storage means, and when the arm position reaches the restriction area, driving of the arm is stopped.