This article studies the adaptive tracking control problem for a class of uncertain nonlinear systems with unmodeled dynamics and disturbances. First, a fuzzy state observer is established to estimate unmeasurable states. To overcome the problem of calculating explosion caused by the repeated differentiation of the virtual control signals, the command filter with a compensation mechanism is applied to the controller design procedure. Meanwhile, with the help of the fuzzy logic systems and the backstepping technique, an adaptive fuzzy control scheme is proposed, which guarantees that all signals in the closed-loop systems are bounded, and the tracking error can converge to a small region around the origin. Furthermore, the stability of the systems is proven to be input-to-state practically stable based on the small-gain theorem. Finally, a simulation example verifies the effectiveness of the proposed control approach.

中文翻译：

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具有未建模动态和扰动的不确定非线性系统的基于小增益技术的自适应模糊命令滤波控制

本文研究了一类具有未建模动力学和扰动的不确定非线性系统的自适应跟踪控制问题。首先，建立一个模糊状态观测器来估计不可测量的状态。为了克服虚拟控制信号重复微分导致的计算爆炸问题，在控制器设计过程中应用了具有补偿机制的指令滤波器。同时，借助模糊逻辑系统和反推技术，提出了一种自适应模糊控制方案，保证闭环系统中的所有信号都是有界的，跟踪误差可以收敛到原点附近的一个小区域。 . 此外，基于小增益定理，系统的稳定性被证明是输入到状态实际上稳定的。最后，