Fuzzy adaptive control: a hyperstability approach

This paper investigates a direct fuzzy adaptive control of continuous-time nonlinear systems. The proposed adaptive scheme uses a Takagi-Seguno (TS) fuzzy controller, which allows the inclusion of a priori information in terms of qualitative knowledge about the plant operating points or analytical conventional regulators (e.g., state feedback) for those operating points. Stability and robustness of this adaptive scheme are studied using the hyperstability tools. It is proven that this adaptive controller is globally asymptotically stable, and robust against external disturbance and approximation error. Fast tracking, low complexity and parameter convergence characteristics of the proposed approach are illustrated by simulation results