Logic-Based Fixed-Time Control for Uncertain Nonlinear Systems With Unknown Control Directions
针对具有多个未知控制方向的不确定非线性系统，提出一种切换机制与新型动态边界函数，使系统输出在固定时间内收敛到原点附近，并保持所有信号有界。
The fixed-time control problem is investigated for a class of uncertain nonlinear systems subjected to multiple unknown control directions. The control coefficients of nonlinear systems under consideration are time varying and their signs are not required to be identical. To tackle this challenge, a switching mechanism along with a novel dynamic boundary function is proposed. Utilizing the devised dynamic boundary function, adaptive parameters are introduced into the controller to effectively handle system uncertainties. It is proved that the system output converges to a small neighborhood of the origin in fixed time and the boundedness of all system signals is maintained. Finally, two simulation examples are used to show the validity of the presented switching control strategy.