SOFC for TS fuzzy systems: Less conservative and local stabilization conditions

The static output feedback control (SOFC) for Takagi-Sugeno (TS) fuzzy systems is addressed in this paper. Based on Lyapunov theory the proposed methods are formulated as Linear Matrix Inequalities (LMIs). To obtain less conservative conditions the properties of membership functions time-derivative are explored. Wiht this new methodology SOFC with higher H_∞ attenuation level can be designed. Moreover, the method is extended to local stabilization using the concepts of invariant ellipsoids and regions of stability. These local conditions overcome some difficulties associated with estimating bounds for the timederivative of the membership functions. Examples are given to illustrate the merits of the proposed approaches.