The main objective of this research is to provide a systematic stability analysis technique for fuzzy systems using well-established results from robust stability of a family of polynomials. The model-based Takagi-Sugeno (TS) fuzzy control system is considered and shown to have a dependent coefficient structure involving firing strengths. Two Kharitonov regions via overbounding are established to facilitate the extreme results for stability test in the space of polynomials as well as the complex plane. The criterion obtained is a sufficient condition for a fuzzy logic controller, Three nonlinear examples are demonstrated to show that the systematic approach proposed here can be used to solve fuzzy stability problems. Fuzzy users concerned over stability issues may find these analytic tools useful.
