状态约束下单连杆机械臂输出反馈自适应跟踪控制

Output-feedback Adaptive Tracking Control for One-link Manipulators Under State Constraints

研究了一类具有全状态约束且状态不可测的单连杆机械手跟踪控制问题。尽管现有的输出反馈跟踪控制方法可以有效地解决状态不可测情况下的机械手位置跟踪控制问题,但未考虑基于操作安全等因素设定的状态受限。同时,系统状态不可测也为实现状态受限带来了挑战。因此,考虑在系统全状态受限并且仅机械手位置可测情况下的输出反馈跟踪控制器设计问题。首先,构造了一个模糊状态观测器来估计不可测状态;然后,通过融合新的状态变换函数和动态表面控制方法,建立了一种基于观测器的自适应模糊控制策略,并利用李雅普诺夫稳定性理论,证明了位置跟踪误差将收敛到零点附近任意小的邻域之内,且系统中的状态永远不会超越约束条件;最后,通过数值模拟验证了所提方法的可行性。

The tracking control problem for a class of one-link manipulators subject to full state constraints and unmeasured state is investigated.Although the existing output feedback tracking control method can effectively solve the robot position tracking control problem in the case of state unpredictability,it does not consider the state constraint problem set based on operational safety and other factors.At the same time,the unmeasurable state of the system also poses a challenge for implementing state constrained.Therefore,this paper considers the problem of designing an output feedback tracking controller for the system with full state constraint and only the robot position is measurable.Firstly,a fuzzy state observer is constructed to estimate the unmeasurable state.Then,an observer-based adaptive fuzzy control strategy is established by fusing a new state transformation function and a dynamic surface control method.By using Lyapunov stability theory,it is shown that the position tracking error will converge to within an arbitrarily small neighborhood near zero,and the states in the system will never exceed the constraints.Finally,the feasibility of the proposed method is verified by numerical simulations.