Augmented Lyapunov–Krasovskii functional approaches to robust stability criteria for uncertain Takagi–Sugeno fuzzy systems with time-varying delays

This paper considers the problem of robust stability analysis for uncertain Takagi–Sugeno (T–S) fuzzy systems with time-varying delays. By constructing an augmented Lyapunov–Krasovskii functional and utilizing Finsler's Lemma, a novel criterion for delay-dependent robust stability of T–S fuzzy model with time-varying delay is derived in terms of linear matrix inequalities (LMIs). Also, a further improved stability criterion is proposed by utilizing free weighting techniques. Finally, three numerical examples are included to show the superiority of the proposed criteria.