Multivariable adaptive sliding mode structure for an observer-based control of a perturbed mechanical system

In this paper, we present the design of an observer-based controller for a perturbed mechanical system using two independent adaptive sliding mode structures (ASMS). The purpose of the proposed method is to compensate for external disturbances, modeling uncertainties and unmodeled dynamics. Assuming that only position measurements are available, the proposed control approach is based on a reduced-order velocity observer. We investigate the stability of the overall closed-loop dynamics. Experiments using a rotary electromechanical system are developed to demonstrate the effectiveness of the proposed design. In addition, comparative results of a similar ASMS control design using a full state-feedback are discussed.