The three-dimensional trajectory tracking of an underactuated autonomous underwater vehicle (AUV) under the complex unknowns including model uncertainties and time-varying disturbances is studied. The reference pitch angle and yaw angle are designed in kinematics, based on the time-varying reference trajectory. Dynamics controllers are developed by incorporating the first-order filter into the dynamic surface control (DSC), which simplifies the design process and overcome differential explosion in the traditional backstepping. To reduce the influence of the complex unknowns, an adaptive fuzzy-based DSC scheme is employed to identify the lumped disturbances with arbitrary accuracy and further enhance system robustness. Lyapunov stability analysis demonstrates that tracking errors are bounded and converge to an arbitrarily small neighbourhood of zero. Finally, simulation studies and comparisons with DSC scheme are carried out to illustrate the effectiveness and superiority of the proposed scheme.

中文翻译：

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基于模糊动态表面控制的欠驱动AUV的三维轨迹跟踪

研究了复杂不确定性（模型不确定性和时变扰动）下欠驱动自动水下航行器（AUV）的三维轨迹跟踪。基于时变参考轨迹，在运动学中设计了参考俯仰角和偏航角。通过将一阶滤波器合并到动态表面控制（DSC）中来开发动力学控制器，从而简化了设计过程并克服了传统反推法中的微分爆炸。为了减少复杂未知数的影响，采用了基于自适应模糊的DSC方案以任意精度识别集总扰动，并进一步增强了系统的鲁棒性。Lyapunov稳定性分析表明跟踪误差是有界的，并且收敛到零的任意小邻域。最后，通过仿真研究和与DSC方案的比较，说明了该方案的有效性和优越性。