具有全状态约束和未建模动态的严格反馈系统有限时间自适应动态面控制

针对一类具有全状态约束、未建模动态和动态扰动的严格反馈非线性系统,通过构造非线性滤波器,并利用Young’s不等式,提出一种新的有限时间自适应动态面控制方法.引入非线性映射处理全状态约束,将有约束系统变成无约束系统,利用径向基函数逼近未知光滑函数,利用辅助系统产生的动态信号处理未建模动态.对于变换后的系统,利用改进的动态面控制和有限时间方法设计的控制器结构简单,移去现有有限时间控制中出现的“奇异性”问题,可加快系统的收敛速度.理论分析表明,闭环系统中的所有信号在有限时间内有界,全状态不违背约束条件.数值算例的仿真结果表明,所提出的自适应动态面控制方案是有效的.

Finite-time adaptive dynamic surface control for strict-feedback systems with full state constraints and unmodeled dynamics

By constructing nonlinear filters and using Young''s inequality, a new adaptive finite-time control method is proposed for a class of strict-feedback nonlinear systems with full state constraints, unmodeled dynamics and dynamic disturbances in this paper. The constrained system is transformed into an unconstrained system by introducing the nonlinear mapping. The radial basis function neural networks are utilized to approximate unknown nonlinear smooth functions. A dynamic signal produced by a auxiliary system is used to deal with unmodeled dynamics. Using the modified dynamic surface control technology and finite-time control method, a simple controller is developed. The singularity problem in the existing finite -time control is removed, and the converging speed of the system is accelerated. Theoretical analysis shows that all signals in the closed-loop system are bounded in finite time. Full state constraints are not triggered. Simulation results of numerical example show that the proposed approach is effective.