In this paper, we address the issue of the prescribed performance control of a class of pure-feedback nonlinear systems with uncertainties and input saturation. The active disturbance rejection control is adopted at each step of the backstepping technology. In detail, the extended state observer is employed to estimate unknown functions to compensate for uncertain items. The tracking differentiator is used to take place of the derivative of the virtual control signals, which overcomes the repeated differentiations of nonlinear functions. The control input limitation is handled with the auxiliary system, and predefined tracking performance functions are utilized to improve the tracking accuracy and speed. By means of the input-to-state stability and Lyapunov stability theory, the tracking error is proven to converge to arbitrarily small neighborhood of the origin. Two simulation examples are provided to demonstrate the effectiveness of the presented results.

中文翻译：

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一类具有输入饱和度的不确定纯反馈非线性系统的指定性能跟踪控制

在本文中，我们解决了一类具有不确定性和输入饱和的纯反馈非线性系统的规定性能控制问题。反步技术的每一步都采用自抗扰控制。具体而言，扩展状态观察器用于估计未知函数以补偿不确定项。跟踪微分器用于代替虚拟控制信号的导数，克服了非线性函数的重复微分。控制输入​​限制由辅助系统处理，并利用预定义的跟踪性能功能来提高跟踪精度和速度。通过输入到状态稳定性和李雅普诺夫稳定性理论，跟踪误差被证明收敛到原点的任意小邻域。提供了两个仿真示例来证明所呈现结果的有效性。