关键词: 非线性系统, 后推, 模糊控制, 最优逼近误差

Abstract: A new robust adaptive indirect fuzzy controller is designed based on backstepping method for a class of uncertain nonlinear systems.The adaptive compensation term of the optimal approximation error and a new robust term are adopted to minify the influence of modeling error and parameter estimation error.The approach does not require the optimal approximation error to be square-integrable or the supremum of the optimal approximation error to be known.It’s proved that the final closed-loop system must be globally stable in the sense that all signals involved must be uniformly bounded and simulation results show that the closed-loop fuzzy control system is proved to be globally stable，with tracking error converging to the arbitrarily small neighborhood of the origin.

Key words: nonlinear systems, backstepping, fuzzy control, the optimal approximation error