Applying wave-variable-based sliding mode impedance control for robot teleoperation

The wave variable approach has the appealing features of not requiring a priori knowledge on both time delay and master/slave plants and simplicity in parameter adjustment, when applied for robot teleoperation. However, its current applications are mainly related to tasks involving position tracking. In this paper, we propose integrating the wave variable approach with the sliding mode impedance controller, so that it can be further applied for robot compliance tasks, in which simultaneous control of both position and force are commanded and contact with the environment is inevitable. We start with the validation of the stability of the proposed wave-variable-based sliding mode impedance control scheme. For demonstration, we apply the proposed system to perform the command-following compliance task in both simulation and experiment.