In this work, the fuzzy adaptive output feedback control is investigated for single-input single-output (SISO) uncertain nonlinear systems in strict-feedback form. The controlled systems under consideration of this work contain the immeasurable states and unknown control gain functions. The immeasurable states are estimated by constructing a fuzzy state observer, and the uncertain nonlinear functions are approximated by fuzzy logic systems. In order to settle the issue of ‘explosion of complexity’ inherent in the conventional backstepping design process, the ‘dynamic surface control’ (DSC) method is introduced. An observer-based fuzzy adaptive control algorithm is proposed by employing the adaptive backstepping control design technique and constructing the Logarithm Lyapunov functions. The designed fuzzy adaptive control scheme can settle the complexity problem of control scheme and insure that the closed-loop system is semi-globally uniformly ultimately boundedness (SGUUB), a simulation example is considered to illustrate the availability of the designed controller.

中文翻译：

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控制增益函数未知的严格反馈非线性系统的模糊自适应动态表面控制

在这项工作中，针对严格反馈形式的单输入单输出 (SISO) 不确定非线性系统，研究了模糊自适应输出反馈控制。这项工作所考虑的受控系统包含不可测量的状态和未知的控制增益函数。通过构造模糊状态观测器估计不可测状态，模糊逻辑系统逼近不确定非线性函数。为了解决传统反步设计过程中固有的“复杂性爆炸”问题，引入了“动态表面控制”(DSC) 方法。采用自适应反步控制设计技术，构造对数Lyapunov函数，提出了一种基于观测器的模糊自适应控制算法。