Abstract—This paper discusses a new observer based intelligent variable structure state tracking controller for nonlinear systems in which the states of the subsystems are assumed to be unavailable for measurement. It is assumed the functions of the system and the interaction terms are unknown. Ultimately boundedness of both observer and tracking errors, boundedness of the controller and observer parameters, Robustness against approximation error and external disturbances are the merits of the observer-based controller design procedure. The simulation results illustrate the good performance of the proposed algorithm.

Index Terms—Lyapunov stability, adaptive control, fuzzy systems, non-canonical non, affine nonlinear systems, nonlinear observer.

The authors are with Department of Electrical Engineering, Damavand Branch, Islamic Azad University, Damavand, Tehran, Iran (e-mail: rezaghasemi@damavandiau.ac.ir).