A new T-S fuzzy observer based controller for nonlinear NCSs

Abstract

This paper concerns the tracking control problem for a class of nonlinear networked control systems (NCSs) with external disturbances. A Takagi-Sugeno fuzzy model is employed to represent the nonlinear controlled plant in the NCSs. Both network-induced delay and packet dropout are addressed. The control scheme is based on a parallel distributed compensation (PDC) structure, a fuzzy observer and a H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">∞</sub> performance to attenuate the external disturbances. The stability of the whole closed-loop model is investigated using a general Lyapunov-Krasovskii functional. The key point of the proposed approaches is to achieve conditions under a linear matrix inequalities (LMI) formulation in the case of a disturbed T-S fuzzy model. This formulation facilitates obtaining solutions through interior point optimization methods for some nonlinear NCSs tracking problems. A numerical example is used to illustrate the validity of the design methodology.