不确定非线性系统自适应动态事件触发输出反馈镇定

本文研究了一类不确定非线性系统的动态事件触发输出反馈镇定问题. 显著不同的是系统具有依赖于不可测状态的增长且增长率为输出的未知多项式. 尽管已有一些连续自适应控制器, 但需要巧妙融合非线性状态观测器、系统未知性的动态补偿以及非线性的抵御, 因此这些控制器具有一定的脆弱性, 不能平凡地拓展到不连续情形 (采样误差导致). 为此, 首先通过引入动态高增益和基于高增益的观测器来分别抵御未知增长率和重构系统不可测状态. 进而, 意识到静态事件触发机制的无效性, 通过引入动态事件触发机制, 成功设计出了事件触发输出反馈控制器, 确保了系统状态的全局有界性和收敛性. 数值仿真验证了所设计控制器的有效性.

Adaptive stabilization via dynamic event-triggered output feedback for uncertain nonlinear systems

This paper is devoted to the global adaptive stabilization via dynamic event-triggered output feedback for a class of uncertain nonlinear systems. Remarkably, the systems admit unmeasured states dependent growth with the rate of unknown polynomial-of-output. Although some continuous adaptive controllers have been proposed, they cannot be trivially extended to the discontinuous (caused by sampled error) context since their fragility stemmed from the skillful integration of nonlinear observer to unmeasured states, dynamic compensation to system unknowns and domination to nonlinearities. To solve the problem, a dynamic high gain and a high-gain-based observer are first introduced to counteract the unknown growth rate and reconstruct the unmeasured system states, respectively. Then noting the ineffectiveness of static event-triggering mechanisms, an event-triggered output-feedback controller is successfully designed by introducing a dynamic event-triggering mechanism to achieve the global boundedness and convergence of the system states. A numerical example is provided to illustrate the validity of the designed controller.