This paper deals with the design, improvement, and implementation of a nonlinear control strategy to solve the trajectory tracking problem for an autonomous underwater vehicle under model uncertainties and external disturbances. First, a disturbance observer based on high-order sliding mode control is designed to counteract the negative impact of both parametric uncertainties and bounded external disturbances. Then, the nonlinear control is enhanced through injecting the disturbance estimation into the designed controller. The stability of the closed-loop system with the enhanced proposed nonlinear controller is proven by Lyapunov arguments. Finally, real-time experimental results are also provided to demonstrate the effectiveness of the proposed controller.

中文翻译：

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用于自主水下航行器鲁棒轨迹跟踪的基于观测的非线性比例微分控制

本文涉及非线性控制策略的设计、改进和实现，以解决模型不确定性和外部干扰下自主水下航行器的轨迹跟踪问题。首先，设计了基于高阶滑模控制的干扰观测器来抵消参数不确定性和有界外部干扰的负面影响。然后，通过将扰动估计注入设计的控制器来增强非线性控制。Lyapunov 参数证明了具有增强的非线性控制器的闭环系统的稳定性。最后，还提供了实时实验结果来证明所提出的控制器的有效性。