Direct adaptive fuzzy control for a nonlinear helicopter system

Purpose - To design effective and practical controllers that use the adaptive fuzzy approaches and are applicable to helicopters. Design/methodology/approach - Based on Takagi-Sugeno fuzzy systems, a new direct adaptive fuzzy control scheme is developed for a class of nonlinear multiple-input-multiple-output systems. A simple observer is designed to generate an error signal for the adaptive law. The system states of the system are not required to be available for measurement. Findings - The overall adaptive scheme guarantees all the signals involved being uniformly bounded in the Lyapunov sense. Research limitations/implications - The implementation of this research work needs further investigation. Practical implications - The simplicity of the design algorithm facilitates the application of the design to helicopters by the use of Matlab. Originality/value - Experimental results of a two degree of freedom helicopter are presented to confirm the usefulness of the proposed new control scheme.