Prescribed-Time Output-Feedback Tracking Control of a Class of Time-Varying Output-Constrained Systems
针对存在未知扰动的时变输出受限系统，提出一种预设时间输出反馈跟踪控制方案，通过时变高增益观测器和障碍李雅普诺夫函数，使跟踪误差在预设时间内趋于零，无需全状态信息和扰动边界，并在单连杆机器人上验证有效性。
In this article, the prescribed-time output-feedback tracking control problem for time-varying output-constrained systems with unknown disturbances is addressed. First, based on the parametric Lyapunov equation (PLE), a novel time-varying state observer is constructed by a time-varying high-gain function. Then, a category of prescribed-time output-constrained functions is defined, and a class of time-varying barrier Lyapunovfunctions (BLFs) is developed. Based on these, a time-varying high-gain output-feedback tracking control scheme is designed without requiring full state information and disturbance boundary. It is proved that the proposed controller can drive the tracking error of the time-varying output-constrained system to tend to zero in a prescribed time under unknown disturbances. Finally, the prescribed-time tracking control approach is applied to a single-link robot, and several numerical simulations validate the effectiveness of the proposed method.