Adaptive position/force control for robot manipulators in contact with a rigid surface with uncertain parameters

Most position/force control schemes assume that the contact surface is exactly known. In the presence of constraint uncertainties these controllers cannot ensure convergence to zero of position and force errors. In this work, an adaptive scheme is proposed for robot manipulators that perform interaction tasks with rigid surfaces. Both robot and constraint surface parameters are considered to be uncertain. The proposed scheme locally estimates the surface by means of force measurements. Experimental results are presented to illustrate the good performance of the proposed approach.