PURPOSE: To improve the safety and operationability of a slave manipulator by changing the moving speed of a slave arm to prevent the unprepared movement of the slave arm even when a parameter is changed.

CONSTITUTION: When a factor (an) in a technological converting section 1 on the side of a master arm has been changed into (a'n) to change the moving speed of a slave arm to the master arm, a constant (bn) on the side of the master arm is changed into (b'n) so that the value y1 of a target value yn to the value x1 of then master position signal xn may become the same, and technological conversion on the side of the master arm is hereafter executed using changed factors (a'n) and (b'n) to operate the slave arm at changed moving speed.