Globally Stable Adaptive Fuzzy Control for Strict-feedback Nonlinear Systems

A new adaptive fuzzy controller for uncertain strict-feedback nonlinear systems is proposed. All the previous approximator-based adaptive control algorithms for the strict-feedback nonlinear systems are based on backstepping scheme and guarantee semi-global closed-loop system stability. This paper proposes a new globally stabilizing adaptive fuzzy controller for strict-feedback nonlinear system without backstepping. To this end, an online self-structuring adaptive fuzzy system is employed. The proposed adaptive fuzzy controller is considerably simpler than the previous ones based on backstepping. Only one FLS is employed to approximate a lumped uncertain nonlinearity, which highlights the simplicity of our proposed control scheme.