输入饱和下的船舶风帆三自由度控制系统固定时间预设性能滑模控制

Afixed-time prescribed performance sliding mode control of ship sail three-degree-of-freedom control system under input saturation

中文关键词  船舶风帆三自由度控制系统  固定时间滑模控制  运动控制  输入饱和  预设性能  角度约束  双极限齐次 定理

英文关键词  ship sail three-degree-of-freedom control system  fixed-time sliding mode control  motion control  input saturation  prescribed performance  angle constraint  bi-limit homogeneous property

中文摘要

      针对船舶风帆三自由度控制系统的目标角度跟踪控制过程中存在的外部强风扰动、输入饱和、角度约束 问题以及平稳快速跟踪需求,提出了一种考虑输入饱和的固定时间预设性能滑模控制方法(FTSMC-PP-IS).首先, 基于双极限齐次性定理(BHP)构建固定时间收敛滑模面,在避免控制律奇异性情况下实现更快的固定时间收敛特 性;其次,设计预设性能函数(PPF)以满足系统的三自由度角度约束,并优化跟踪超调量和跟踪误差;再次,设计了固 定时间辅助系统来补偿执行器输入饱和偏差.通过分别构建滑模趋近律和等效控制律,保证系统的全局固定时间 收敛. 值得注意的是,该方法在保证输入饱和下的快速固定时间跟踪的同时,获得了较好的动态特性和稳态特性; 最后,通过Lyapunov稳定性理论证明了所提出方法的固定时间收敛特性.数值仿真和原理样机实验证明了所提出 方法的可行性和有效性.

英文摘要

      To address the challenges posed by external wind disturbances, input saturation, angle constraints, and the need for smooth and rapid tracking, this paper proposes a fixed-time prescribed performance sliding mode control strat egy (FTSMC-PP-IS) for the three-degree-of-freedom control system of ship sail. Firstly, a fixed-time convergent sliding mode surface is developed using the bi-limit homogeneous property (BHP) to ensure rapid fixed-time convergence while avoiding singularities in the control law. Next, a prescribed performance function (PPF) is designed to meet the system’s three-degree-of-freedom angle constraints and to optimize tracking overshoot and steady error. Additionally, a fixed-time auxiliary system is introduced to compensate for actuator input saturation deviations. The global fixed-time convergence of the system is assured by constructing the sliding mode reaching law and the equivalent control law. Notably, this approach achieves excellent dynamic and steady-state performance while ensuring rapid fixed-time tracking under input saturation conditions. Finally, the fixed-time convergence of the proposed method is validated through Lyapunov stability theory. Numerical simulations and prototype experiments confirm the feasibility and effectiveness of the proposed method.