Master-slave" robot computer

Citation

(2002), "Master-slave" robot computer", Industrial Robot, Vol. 29 No. 2. https://doi.org/10.1108/ir.2002.04929bab.002

"Master-slave" robot computer

Keywords: Robots, Teleoperation

The Japanese government's Mechanical Engineering Laboratory has developed a new method of remotely operating robots so as to eliminate the conventional troubles of matching exactly the movements between the actual job performing "slave" section of the robot's system and the instruction-giving "master" section. This system, in which the slave section performs detailed tasks in certain humanly inaccessible and dangerous places including nuclear power plants, has been used, says the Laboratory at Sakuramachi in Ibaraki Prefecture, by the Agency of Industrial Science and Technology of the government's Ministry of International Trade and Industry (MITI) in Tokyo.

That system, however, has been plagued by many troubles, such as the human operator's inevitable duties of having to move the master section's equivalent to copy all moves, changing the master and slave section machinery according to the requirements of increasingly complex jobs to be done. Both master and slave section machines now come in three varieties – the "joint" to do human arm-like movements, the "polar coordinates" to rotate or extend or contract the arm in addition, and the "orthotomic coordinates" to work pantograph-style.

The Laboratory says all such troubles are eliminated by its newly developed process whereby a microcomputer is inserted between the master and slave sections of such a robot system. Differences in the working formula between the two sections will no longer matter since the computer will adjust them. In addition, the slave section's manipulating arm is equipped with various sensors to record the arm's positions, the working speed, the torques, and all the other conditions and keep the operator constantly informed of them.

The only drawback of this new system is the complexity of the computer to process different coordinates. The computer's working speed is now being increased to meet the requirements of six different kinds of manipulating arm movements. An experimental hardware system built by the laboratory to test its process has shown that a set of master and slave sections of different working formulae works quite well and rapidly if the computer processes each round of coordinates in twelve milliseconds.

The system, in theory, promises push button remove operation of robots from a long distance.