JPH04326404A - Controller for robot - Google Patents

Abstract

PURPOSE:To prevent long time required for recovering a robot and debugging an operation program being caused by the robot stopping within an operational range while the arm of the robot is moving. CONSTITUTION:Before starting the movement of the arm, an operating route calculating means 21 calculates all the positions on an operating route according to a current position in a current position buffer 14 and an objective moving position in an objective moving position buffer 13 and the calculated result is written in a commanded position buffer 22. A commanded position operational range judging means 23 judges whether all the commanded positions on the operating route are within the operational range of the arm or not. When they are out of the operational range, an abnormal signal 18a is outputted from an alarm generating means 18, the movement of the arm is blocked, and the arm is prevented from stopping during the movement.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling a robot using a teaching/playback method or a numerical control method.

0002

2. Description of the Related Art FIGS. 3 and 4 are diagrams showing conventional robot control devices, with FIG. 3 being a block diagram and FIG. 4 being an overall configuration diagram. In Figure 3, 1 is C that manages the entire robot.
PUA, 2 is a ROM that stores a control program, 3 is a RAM that stores calculation data, 4 is a program memory that stores an operation program and position data for making the robot perform a desired work, 5 is each of the CPUA 1 Shared memory where commands are written, 6 is a CP that controls the servo system
UB, 7, and 8 are ROMs and RAMs corresponding to ROM2 and RAM3, respectively; 9 is a servo interface connected to the motor of each axis within the robot body 10; and 10a is an arm of the robot.

In FIG. 4, 11 is a program memory 4.
12 decodes the movement program from the current position stored in the current position buffer 14, which will be described later, and the movement program 11 stored in the program memory 4, and determines the target position of the robot. 13 is a target position buffer that stores the robot's movement target position; 14 is a current position buffer that stores the robot's current position; 15 is the current position stored in the current position buffer 14; and the target position. A command generating means calculates the command position at the next time point from the target position stored in the buffer 13, and 16 is a next time command position buffer that stores the calculated next time command position, which is stored in the RAM 3. ing. Reference numeral 17 denotes next point command position operation range determining means for determining whether the next point command position stored in the next point command position buffer 16 is within the operation range of the arm 10a, and 18 denotes next point command position operation range determining means 17. This is an alarm generating means that outputs an abnormality signal 18a to the outside in response to a command from the controller.

A conventional robot control device is constructed as described above, and its operation will be explained below. First, the CPU 1 reads the robot operation program from the program memory 4, and the program execution means 12 writes the target position into the target position buffer 13. The command generating means 15 reads the current position and the target position, calculates the next time command position, and writes it into the next time command position buffer 16. The next point command position operation range determining means 17 reads the next point command position, and if it is outside the movement range of the arm 10a, it issues a command to the alarm generating means 18, and the alarm generating means 18 sends an abnormality signal 1.
Outputs 8a. At the same time, the CPUA1 writes a command to stop the robot in the shared memory 5, and the CPUB6 stops the robot body 10. If it is within the operating range, the current position is updated and the numerical value is written into the current position buffer 14. The CPUB 6 executes the above operation every unit time until it reaches the target position.

As described above, when it is confirmed that the target position Pa shown in FIG. 5 is within the movement range of the arm 10a during the trajectory interpolation operation, the arm 10a moves to the current position Pb.
When the arm 10a starts moving and detects interference with the robot body 10 during the movement, the arm 10a is stopped to prevent this.

[0006]

[Problem to be Solved by the Invention] In the conventional robot control device as described above, during trajectory interpolation operation, the target position P
If a is within the movement range of the arm 10a, the arm 10a is moved without checking the movement path, so if it goes outside the movement range of the arm 10a during movement, the arm 10a will stop and the robot will be restored. It takes time to work,
There is a problem in that it takes time to debug the operating program.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a robot control device that can restore the robot after an abnormality occurs and shorten the debugging time of the operation program. .

[0008]

[Means for Solving the Problems] A robot control device according to the present invention calculates a movement path to a movement target position before a moving body of the robot starts moving, and calculates a movement path of the robot at each point on the movement path. It is determined whether the position is within the operating range, and if it is determined that the position is outside the operating range, the movement of the moving body is prevented.

[0009]

[Operation] In this invention, since the movement path of the moving body of the robot is confirmed before the robot starts moving, the moving body does not enter an area outside the movement range and stop during movement.

0010

[Embodiment] FIGS. 1 and 2 are diagrams showing an embodiment of the present invention. FIG. 1 is an overall configuration diagram, and FIG. 2 is a flow chart.
Portions similar to those of the conventional device are designated by the same reference numerals. Note that FIG. 3 is also used in this embodiment.

In FIG. 1, 21 is the destination position buffer 1.
3 and a motion route calculation means for calculating the position on the motion route from the current position buffer 14; 22 is a motion route calculation means 21;
23 reads n command positions from the command position buffer 22. , is a command position operating range determining means that determines whether all command positions are within the operating range.

Next, the operation of this embodiment will be explained with reference to FIG. First, in step 31, the movement target position is written into the target position buffer 13 as in the conventional apparatus. Next, in step 32, the motion route calculation means 21 calculates all positions on the motion route from the current position and the movement target position,
The result is written into the command position buffer 22. In step 33, the command position motion range determining means 23 determines whether all command positions on the motion path are within the motion range of the arm 10a.

As a result, if it is determined that it is within the operating range, the process advances to step 34 and is processed in the same manner as in the conventional apparatus. That is, in step 34, the next point-in-time command position is calculated and written into the next point-in-time command position buffer 16. Next, in step 35, the next point command position operating range determining means 17 determines whether the next point command position is within the operating range. If it is within the operating range, the current position buffer 14 is updated in step 36,
In step 37, the current position is output to the command generating means 15, and steps 34 to 37 are repeated until the robot reaches the target movement position.

If it is determined in step 35 that the robot is outside the operating range, the process proceeds to step 38, where the alarm generating means 18 outputs an abnormality signal 18a, and the CPU 6 issues a command to stop the robot. Further, if at least one of all commanded positions on the operating path is outside the operating range in step 33, the process proceeds to step 39, in which the abnormality signal 18a is similarly output and the arm 10a is
prevent the movement of

[0015]

[Effects of the Invention] As explained above, in this invention, before the moving object of the robot starts moving, the movement path to the movement target position is calculated, and the position of the moving object at each point on this movement path is calculated. It is determined whether the moving object is within the movement range, and if it is determined that it is outside the movement range, the movement of the moving object is blocked, so the movement path of the moving object can be confirmed before the movement starts, and the robot can be recovered after movement is blocked. This also has the effect of shortening the debugging time of operating programs.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing an embodiment of a robot according to the present invention.

FIG. 2 is a flowchart showing the operation of FIG. 1;

FIG. 3 is a block diagram showing a conventional robot control device.

FIG. 4 is an overall configuration diagram of FIG. 3;

FIG. 5 is an arm movement locus diagram of the robot in FIG. 3;

[Explanation of symbols] 10 Robot main body 10a Moving body (arm) 13 Target position buffer 14 Current position buffer 15 Command generation means 16 Next time point command position buffer 17 Next time point command position operation range judgment means 18
Alarm generation means 21 Operation path calculation means 22 Command position buffer

Claims (1)

[Claims] Claim 1. A robot that calculates a next point command position, moves the moving object to the next point if it is within the movement range of the moving object, and repeats this process until the movement target position. a motion path calculation means for calculating a motion path of the movable body to the movement target position; and a command position motion range for determining whether each position of the movable body at each point on the motion path is within the motion range. A control device for a robot, comprising a determining means and an alarm generating means for preventing movement of the movable body when the position of the movable body is determined to be outside the operating range.