Observer-based H∞H∞ fuzzy control design for T–S fuzzy systems with state delays

This paper is concerned with the problem of observer-based H∞H∞ fuzzy control design for Takagi–Sugeno (T–S) fuzzy systems with time-delay. The main contribution is that an effective matrix decoupling technique is developed to derive a single-step LMI condition for observer-based H∞H∞ control design. This overcomes the drawback of two-step LMI approach in the literature. When restricted to delay-free fuzzy systems, the present result is shown less conservative than existing ones. An illustrative example is given to show the effectiveness of our results.