Xia Jianwei, Lian Yuxiao, Su Shun-Feng, Shen Hao, Chen Guoliang
IEEE Trans Cybern. 2022 Oct;52(10):10655-10666. doi: 10.1109/TCYB.2021.3069853. Epub 2022 Sep 19.
The issue of adaptive output-feedback stabilization is investigated for a category of stochastic nonstrict-feedback nonlinear systems subject to unmeasured state and unknown control directions. By combining the event-triggered mechanism and backstepping technology, an adaptive fuzzy output-feedback controller is devised. In order to make the controller design feasible, a linear state transformation is introduced into the initial system. At the same time, the Nussbaum function technology is used to overcome the difficulties caused by unknown control directions, and the state observer solves the problem of the unmeasured state. Based on the fuzzy-logic system and its structural characteristics, the issue of unknown nonlinear function with nonstrict-feedback structure in the system is tackled. The designed controller could not only guarantee all signals of closed-loop systems are bounded in probability but also save communication resources effectively. Finally, numerical simulation and ship dynamics example are given to confirm the effectiveness of the proposed method.
针对一类具有不可测状态和未知控制方向的随机非严格反馈非线性系统，研究了自适应输出反馈镇定问题。通过结合事件触发机制和反步法技术，设计了一种自适应模糊输出反馈控制器。为使控制器设计可行，对初始系统引入线性状态变换。同时，利用Nussbaum函数技术克服未知控制方向带来的困难，状态观测器解决不可测状态问题。基于模糊逻辑系统及其结构特性，处理了系统中具有非严格反馈结构的未知非线性函数问题。所设计的控制器不仅能保证闭环系统的所有信号依概率有界，还能有效节省通信资源。最后，通过数值仿真和船舶动力学实例验证了所提方法的有效性。
