Observer‐based adaptive fuzzy dynamic surface control of non‐linear non‐strict feedback system

Abstract

This study develops a scheme of an adaptive fuzzy dynamic surface control (DSC) for a non-linear non-strict feedback system with immeasurable states. By utilising the universal approximation property of a fuzzy logic system, a state observer is designed to estimate the unmeasured states. Based on the back-stepping DSC design technique, an adaptive fuzzy output feedback control design method is developed. The proposed method can overcome the ‘explosion of complexity’ problem, and also can eliminate the limitation of the measurable states. It is proved that the control method can guarantee that all the signals in the closed-loop system are bounded and the system output can track the given reference signal well. The simulation results are provided to demonstrate the effectiveness of the proposed control method.