Nonlinear Robust Output Stabilization for Mechanical Systems Based on Luenberger-Like Controller/Observer

Abstract

This paper addresses to demonstrate the uniform-ultimately bounded stability (uniformly-ultimately-bounded (UUB)-stability) of the proportional derivative (PD+) compensator where, the joint velocity is not available to be measured but rather it is estimated. The proposed stabilization control strategy is developed for a “n” degrees-of-freedom (DOF) robotic manipulator process, where the joint speed is not available to be measured; furthermore, the external disturbances and/or uncertain dynamics are considered in the system dynamics. To conclude the closed-loop robust stabilization, the proposed feedback strategy is based on the nonlinear state estimation with a Luenberger-like observer and the classical PD+ used in robot manipulators.