This paper studies the issue of event-triggered adaptive fixed-time control for uncertain large-scale nonlinear systems. A state observer is employed to estimate unknown states. By combining the technologies of command filter and backstepping control, a command filtered-based fixed-time adaptive control approach is proposed, which can cope with the issue of ‘complexity explosion’ in the backstepping design scheme. Meanwhile, a novel continuous hyperbolic tangent function is designed to handle the difficulty of fixed-time stability analysis with output-feedback control form, where two types of observer errors are needed in the designed Lyapunov function to achieve the fixed-time stability. Further, based on the event-triggered strategy, an event-triggered fixed-time adaptive controller is designed. Based on Lyapunov stability theory, it is proven that all signals of the closed-loop system are bounded. Finally, the effectiveness of the presented approach is validated by a simulation.

本文研究了不确定大规模非线性系统的事件触发自适应固定时间控制问题。使用状态观察器来估计未知状态。结合指令滤波和反步控制技术，提出了一种基于指令滤波的固定时间自适应控制方法，可以解决反步设计方案中“复杂度爆炸”的问题。同时，设计了一种新颖的连续双曲正切函数来解决具有输出反馈控制形式的固定时间稳定性分析的困难，其中设计的Lyapunov函数需要两种类型的观测器误差来实现固定时间稳定性。进一步，基于事件触发策略，设计了事件触发的固定时间自适应控制器。基于李雅普诺夫稳定性理论，证明闭环系统的所有信号都是有界的。最后，通过仿真验证了所提出方法的有效性。