JPH03287393A - Control method of manipulator - Google Patents

Abstract

PURPOSE:To quickly perform fault return of a manipulator, by controlling so as to continue the motion by the other driving source of the joint just as the driving source of the joint that failure is detected being stopped, in the case of the failure of either joint being detected by the information detected by a sensor. CONSTITUTION:Control is performed so as to continue motion 8 by the other joint driving source, just as the driving source of the joint that fault is detected being stopped 7, in the case of the fault 9 of either joint being detected by the information that a sensor detects. Namely, the posture of the manipulator of the fault time is released by the driving of the joint excluding the joint that the fault 9 is detected. Thereafter, the restoration of the fault is taken by performing the restoration processing of the fault joint.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a control system for a manipulator, and is particularly useful when applied to a multi-joint master-slave manipulator.

B. Summary of the Invention The present invention controls, when some joints of a multi-joint manipulator fail, to continue operation using only healthy joints excluding the failed joint, and allows the manipulator to be easily removed from the position at the time of failure. It was made so that it could be taken out.

C. Prior Art A master/slave manipulator is well known as a manipulator having multi-jointed arms.

The master/slave manipulator has a master arm, which is a multi-jointed artificial arm, and a slave arm, and when the operator operates the master arm, the slave arm follows the position of the master arm. It is controlled through a control device and processes the object.

! FIG. 2 is a block diagram showing a general system configuration of a manipulator including the master and slave manipulators. As shown in the figure, the operation/display device 1 is a device for operating the manipulator and displaying the status, and is connected to the control device 2 through Ilo. The control device 2 includes a control processor, a program ROM/RAM, Ilo, and the like. The driver 3 converts the torque command value calculated by the control device 2 into a current command value and supplies the current command value to the motor 5 of the manipulator 4 . At this time, the motor 5 is connected to the manipulator 4
It is provided at each joint. The sensors 5 are installed on each motor shaft of the manipulator 4 to detect position, speed, torque, etc., and the detected values are supplied to the control device 2. The control device 2 directly supplies brake commands for the motor shaft to the manipulator 4 .

FIG. 3 is a block diagram showing a conventional control method in the manipulator system Z. As shown in the figure, the control system according to the prior art is in a stopped state 7 after the power is turned on. At this time, all axes (joints; the same applies hereinafter) are stopped. When the start switch is pressed, the operating state becomes 8,
The manipulator is operated. If a failure occurs in a specific axis during operation, a failure state 9 occurs and all axes stop. Thereafter, when the failure recovery switch is pressed, the operating state returns to 8 only if all axes have recovered. However, if any axis remains in failure, the failure state 9 will occur again and all axes will stop.

D Problems to be Solved by the Invention In the control system according to the prior art, when a failure occurs, even if the failure recovery switch is pressed, the system returns to operating state 8 only if all axes have recovered. Not only does it take time to recover from a failure, but depending on the posture of the manipulator, such as when the hand gets caught in an object during fitting work, failure condition 9 may recur after the failure recovery process, resulting in a permanent failure. There may be cases where it is not possible to extract the material.

SUMMARY OF THE INVENTION In view of the above-mentioned prior art, it is an object of the present invention to provide a control system for a manipulator that can be easily extracted from a failure state.

Means for Solving Problem E11 The structure of the present invention to achieve the above object has a plurality of joints, and a drive source, position, speed, and torque for performing predetermined movements such as turning and rotation. In a control method for a manipulator that has a sensor for each joint to detect information for driving the manipulator, if a failure in any joint is detected based on the information detected by the sensor, the failure is detected. It is characterized in that while the drive source of the joint remains stopped, the drive source of the other joint is controlled to continue the motion.

F Effect According to the present invention having the above configuration, the posture of the manipulator at the time of failure is released by driving the joints other than the joint in which the failure has been detected. Thereafter, recovery from the failure is attempted by performing recovery processing for the failed joint.

G example Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 (2) is a block diagram showing a control method according to an embodiment of the present invention.The control method according to the present embodiment has a plurality of axes (joints: hereinafter the same), and is capable of turning, rotating, etc. a driving source, position, and speed for performing a predetermined operation;
This is applied to a manipulator that has a sensor on each axis for detecting information such as torque for driving the manipulator.

As shown in FIG. 1, when a failure occurs in a specific axis in operating state 8, only this axis is set to a failure state f19. In other words, each axis can be operated while the healthy axis 1 remains in the M rotation state 8.

As shown in FIG. 2, the failure at this time is detected by the controller 2 determining the information generated by the sensor 6, and the motor 5, which is the drive source of the axis where the failure was detected.
At the same time, the control device 2 interrupts the current through the driver 3 and operates the brake on the shaft of the motor 5.
control

If the failure tXgl switch is pressed after the specific axis is in failure state 9, the axis returns to operating state 8 if the failure axis has been restored. On the other hand, if the failed axis has not recovered,
The axis remains in the failure state 9, but since the healthy axis is in the operating state 8, the attitude of the manipulator is changed by driving the healthy axis, thereby changing the environment of the failure axis. As a result, it is also possible to recover from failure state 9 by pressing the failure recovery switch.

Note that the failed axes may be separated by dividing the axes into a plurality of groups and separating each group. That is, if the axis is divided into, for example, the hand section and other groups, and any axis belonging to the group is in the failure state 9, the entire group may be placed in the failure state 9.

(2) Effects of the Invention As described above in detail in conjunction with the embodiments, according to the present invention, the manipulator failure tl [return can be quickly performed, and equipment failures can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a control method according to an embodiment of the present invention, FIG. 2 is a block diagram showing a general system configuration of a manipulator, and FIG. 3 is a block diagram showing a control method according to the prior art. It is a diagram. In the drawing, 2 is a control device, 4 is a manipulator, 5 is a motor, 6 is a sensor, 8 is an operating state, and 9 is a failure state. Figure 1 Control system (example system) Figure 2 Manipulator system configuration diagram Manipulator

Claims (1)

[Claims] A manipulator that has multiple joints and a drive source for performing predetermined movements such as turning and rotation, and a sensor for each joint that detects information for driving the manipulator such as position, speed, and torque. In this control method, if a failure in any joint is detected based on the information detected by the sensor, the drive source of the joint where the failure was detected remains stopped and the drive source of the other joint continues to operate. A control method for a manipulator that is characterized by controlling.