1.Beijing Institute of Space Mechanics & Electricity;2.Northwestern Polytechnical;3.Dalian Maritime University
The National Key Technologies R&D Program of China
本文针对自主水下航行器的路径跟踪控制问题, 首先, 将基于路径坐标系和虚拟向导的概念建立的跟踪误差方程转换成一种新的级联系统的表示形式, 由一个位置误差名义系统和与之级联的速度和航向误差子系统组成, 与常规控制器求解相比解耦了位置误差与速度和航向误差子系统. 其次, 利用滤波反步法对速度和航向子系统进行求解, 避免了反步法对虚拟控制量解析求导引起的“计算膨胀”的不足, 并通过构造辅助系统对滤波误差和输入受限下的控制量残差进行补偿, 基于李雅普诺夫稳定性理论保证了速度和航向子系统的有界收敛. 然后, 通过级联系统理论证明了闭环跟踪误差系统所有信号的一致最终有界. 最后, 通过仿真实验验证了级联控制的有效性.
This paper solves the path-following control problem of an Autonomous Underwater Vehicle (AUV). Firstly, the path-following error dynamics is established with the concept of path coordinate frame and virtual target, and then transformed into a novel cascade form, which is consist of two subsystems cascaded with the interconnection function, one is position tracking error subsystem and another is surge speed and yaw angle tracking error subsystem, the cascade form decouples the position tracking error subsystem from surge speed and yaw angle tracking error subsystem compared to the traditional solution. Then, command filtered backstepping is adopted to stabilize the surge speed and yaw angle subsystem, which can avoid the complexity and explosion in computing the analytic derivatives of virtual controls, and the filtered tracking errors and input saturation bias are compensated through constructing an auxiliary system with guaranteed bounded stability under Lyapunov theorem. Further, the overall cascade system stability can be proven that all the signals in the closed-loop are uniformly ultimately bounded. Finally, the simulation results are presented to illustrate the effectiveness of the proposed scheme.