An adaptive law for slope identification, position tracking and force regulation for a robot in compliant contact with an unknown surface

This work deals with the problem of force regulation and position trajectory tracking for a robot in compliant contact under kinematic uncertainties. A robotic finger with a soft hemispherical tip of uncertain compliance is considered in contact with a rigid flat surface of unknown position and orientation. A novel adaptive controller is proposed and is proved to achieve the convergence of force and position errors to zero by identifying the slope given a persistently excited desired velocity. The performance of the proposed controller is demonstrated by a simulation example.