Unknown Nonaffine High-Order Fully Actuated Systems: Trajectory Tracking and Fault Tolerance
针对未知非仿射高阶全驱动系统，提出基于扩展状态观测器的跟踪控制器和鲁棒容错镇定控制器，确保跟踪误差和观测误差收敛到零附近，并处理乘性执行器和传感器故障。
In this article, the nonaffine high-order fully actuated system (HOFAS) structure is established, and a tracking controller and a robust fault-tolerant stabilization controller for unknown fully actuated systems are proposed. Starting from the unknown nonaffine HOFAS model, a saturated controller dynamic equation based on extended state observer is yielded, which ensures the low-power characteristics of the controller. Both the observation error and tracking error are shown to converge eventually, and the upper error bound can be adjusted to a small neighborhood near zero. Furthermore, for unknown nonaffine HOFASs with multiplicative actuator and sensor faults, a robust fault-tolerant stabilization controller is presented to guarantee the ultimately uniformly bounded stability and the convergence to zero. The main results are proved theoretically and illustrated experimentally.