Relaxed stability conditions for continuous-time Takagi-Sugeno fuzzy systems based on a new upper bound inequality.

The important issue of reducing the conservatism of feasible stability criteria for continuous-time Takagi-Sugeno fuzzy systems is studied in this article. In order to obtain more advanced result than previous ones, a new upper bound inequality is proposed and thus the properties of the normalized fuzzy weighting functions' time derivatives can be better used than the previous ones. In particular, the so-called redundant terms considered in previous literature can be converted to useful terms which play a positive role in the underlying analysis process. Moreover, some useless additional variables and their derived inequalities are removed for enhancing the efficiency. Finally, an illustrative example is given to show the effectiveness of the proposed method. (c) 2016 Wiley Periodicals, Inc. Complexity 21: 289-295, 2016