Discontinuous piecewise parametric modeling and compensation control for manipulator systems with friction

A novel compensation control based on intelligent modeling for joint friction in manipulator systems is proposed in this paper. The modeling algorithm exploits the discontinuous piecewise parametric representation (DPPR) as the estimator of generalized friction while the controller is a non-model feedforward compensator. The DPPR modeling captures the main characteristics of friction including Stribeck effect, discontinuous at zero, Coulomb and viscous friction. Dynamics knowledge of the plant is not required. The stability of the proposed scheme is analyzed by the Lyapunov criterion. Simulation results show that the proposed controller performs well for a 3-link manipulator system.