Application of Soft Actuation to Bilateral Control and Haptic Reproduction

Abstract

The main research topic of this paper is to apply the sliding mode based soft actuation to smooth transition between position, force, and impedance control, and realize bilateral control and reproduction of the haptic motion. The proposed design rests on the sliding mode two steps procedure: in the first step, the generalized error - the sliding mode function - is selected in such a way that a closed loop system exhibits a desired dynamics. In the soft actuation method, the generalized error depends on the position and the force, thus allowing the modification of the position tracking if interaction with the environment appears. In the second step, the control is selected to enforce the desired convergence rate and the stability of the closed loop dynamics. The control allows natural - human-like behavior. The application to the bilateral control and reproduction of the haptic motion is discussed in detail and verified by experiments.