针对一类完全非仿射纯反馈非线性系统,提出了一种新的自适应动态面控制方法.应用中值定理将未知非仿射输入函数进行分解,使其含有显式的可控制输入参数;引入Nussbaum增益函数,解决了虚拟控制增益符号未知的问题,同时避免了反馈线性化方法中可能出现的控制器奇异性问题;动态面控制消除了传统反推设计中的"微分爆炸"问题.采用解耦反推方法,基于李亚普诺夫稳定性定理证明了闭环系统的半全局稳定性,数值仿真验证了方法的有效性.
A novel adaptive dynamic surface control approach is proposed for a class of completely nonaffine purefeedback nonlinear systems.Based on the mean value theorem,the unknown non-affine input functions are decomposed into new ones with explicit controllable input parameters.The Nussbaum gain function is employed to resolve the unknown gain symbol problem in virtual control,and avoid the possible singularity of the controller in feedback linearization process.The explosion of terms problem in traditional backstepping design is eliminated by utilizing dynamic surface control.Based on Lyapunov stability theorem and decoupled backstepping method,the semi-global stability of the close-loop system is proved.Simulation results show the effectiveness of the proposed approach.