研究了一类非匹配不确定性非线性系统自适应跟踪问题,在假设系统模型不确定参数未知时,结合Backstepping的递推方法和鲁棒控制技术,经过多步递推设计了输出反馈控制器和参数自适应控制律.通过控制参数调节,对存在非匹配不确定性和未知干扰的非线性系统实现了输出跟踪.基于Lyapunov稳定性理论所设计的控制器不仅使系统的输出跟踪给定的期望输出,而且使得系统对于所允许的不确定系统状态全局一致有界.与经典反演设计相比,本方案允许非参数化不确定性,增强了控制系统的鲁棒性.最后的仿真算例验证所设计控制方法的有效性.
The robust adaptive tracking for a class of mismatched uncertain nonlinear systems is discussed. Assumed that the parameters of uncertain system model are unknown, combining backstepping design with robust control technology, a robust output feedback control scheme and an adaptive parameter control law are developed. It is proved that the derived robust adaptive controller based on Lyapunov stability theory can guarantee the global, uniform and ultimate boundedness for all states of the closed system. Compared with the classical adaptive backstepping procedure, it allows the nonparametric uncertainties in the last equations of the systems. The robustness of the closedloop system is enhanced. Simulation result demonstrates the effectiveness of this method.