Experimental results for a robust position and force controller implemented on a direct drive robot

In this paper we present the results obtained from the implementation of a robust position/force controller on a two-degree-of-freedom direct drive robot. The controller is based on the theoretical work presented by McClamroch et al. (1988) and Grabbe et al. (1993), which guarantees globally uniformly ultimately bounded (GUUB) position tracking error and bounded force tracking error. The controller accomplishes this stability result in spite of robot model uncertainty and only requires: joint position and velocity measurements, end-effector force measurements, and bounds on the model parameters. Experimental results described in this paper serve to verify the theoretical claims