The paper deals with the following motion of a three-dimensional rectangular robot. The following motion of the robot is considered in two separate modes namely, the Positioning Mode (P. M. ) and the Following Mode (F. M. ). To implement robot control, a new algorithm of combining the two modes is proposed. Furthermore, the stability of the system is implemented by using P. M. such that the robot is controlled to move along an adequate path which is estimated from the reaction force.