Experimental study of position-position and force-position control methods in teleoperation

In this paper, an experimental study of two control strategies for teleoperation is performed on a simple one degree-of-freedom (dof) mechanism made of two parallel arms. First, the so-called position-position scheme is implemented using controllers with an integrating action in order to achieve zero steady-state position error in contact free movement and the shortcomings of this approach are exhibited. Next they are overcome thanks to a force-position control scheme involving a controller switching mechanism so that the integrating action is only active in contact free motion. The so-called conditioning technique is used to avoid windup in the proposed control architecture (a multi-controller cascade scheme).