“…Based on the T-S fuzzy model framework, many systematic approaches for stability analysis, observer design, and control synthesis are CONTACT Xin Wang xwang@siue.edu studied in the literature. Particularly, the control synthesis based on quadratic Lyapunov function approaches has been extensively studied in Fang, Liu, Kau, Hong, & Lee (2006); Kim & Lee (2000); Liu & Zhang (2003); Sala & Arino (2007); Teixeira & Zak (1999); Teixeira, Assuncao, & Avellar (2003);and Tuan, Apkarian, Narikiyo, & Yamamoto (2001). Since a common quadratic Lyapunov function is independent of fuzzy membership functions, the results based on a single Lyapunov function might be conservative.…”