Adaptive Control Schemes for Discrete-Time T–S Fuzzy Systems With Unknown Parameters and Actuator Failures

This paper develops a new solution framework for adaptive output feedback fuzzy control systems aimed at effectively dealing with nonlinear systems with multiple input-multiple output (MIMO) delays and in the presence of dynamics and actuator failure uncertainties. Takagi-Sugeno (T-S) fuzzy systems are employed to represent nonlinear systems, which have desired capacity for dynamic system approximation with parametric and structural properties suitable for using rigorous feedback control techniques. A multiple-delay fuzzy system prediction model is derived and its system properties are clarified. Such a prediction model enables the use of a model-based approach for fuzzy control. The design and analysis are presented for an adaptive control scheme for multiple-delay T-S fuzzy systems, as well as for an adaptive actuator failure compensation scheme for systems with redundant actuators subject to uncertain failures, for which new system parametrizations and controller structures are developed. Simulation results are presented to demonstrate the studied new concepts and to verify the desired performance of the new types of adaptive fuzzy control systems.