This article develops an approximation-based fuzzy control scheme for nonstrict feedback stochastic nonlinear systems (NFSNS) with time-varying state constraints. The difficulty in constructing controller is how to conquer the algebraic loop problem caused by nonstrict feedback structure, as well as prevent the state constraints from violating. To dispose the time-varying state constraints, time-varying barrier Lyapunov function is incorporated into the backstepping design framework. The lumped uncertainties of NFSNS are approximated by the fuzzy logic systems. By virtue of fuzzy basis function, the algebraic loop problem is effectively handled. Theoretical analysis shows that the predefined state constraints are not violated and all signals of the closed-loop systems are bounded. Finally, simulation results substantiate the validity of the devised method.

中文翻译：

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具有时变状态约束的非严格反馈随机非线性系统的模糊逼近自适应控制

本文为具有时变状态约束的非严格反馈随机非线性系统 (NFSNS) 开发了一种基于近似的模糊控制方案。构造控制器的难点在于如何克服由非严格反馈结构引起的代数环问题，以及如何防止违反状态约束。为了处理时变状态约束，时变势垒李雅普诺夫函数被纳入反步设计框架。NFSNS 的集中不确定性由模糊逻辑系统近似。借助模糊基函数，有效地处理了代数环问题。理论分析表明，没有违反预定义的状态约束，闭环系统的所有信号都是有界的。最后，