Normally, in the case of rotation in the manual mode, the arm and/or the hand rotate without the position coordinates of the tip of the hand changed. The external TCP function enables the arm and/or the hand to rotate about the predetermined coordinate origin of a workpiece. This function can reduce the number of teaching points at the time of continuous path motion (straight or arc) of the robot holding a workpiece, e.g. deburring workpieces using a Leutor that is fixed to the equipment or the application work of a seal on workpieces with a fixed seal gun.