摘要
针对一类二自由度欠驱动机械系统,提出了一种基于趋近律法的分级滑模控制策略。该控制策略的基本原理是将一种非线性趋近律引入到系统的控制机制中,该趋近律能够动态地适应被控系统滑动面的变化,可使控制器保持良好性能并削弱系统的抖振。所提控制策略首先将整个系统划分成2个子系统,并对各子系统分别定义第一级滑动面。然后将第一级各滑动面组合成第二级滑动面,并利用第一级各滑动面的等效控制量来构造滑模控制律。基于第二级滑动面和提出的趋近律来求取系统的切换控制量,从而最终获得系统的控制输入量。从理论上分析了闭环系统的稳定性,并通过车摆系统的仿真实验验证了该控制策略的有效性。
A hierarchical sliding mode control scheme based on reaching law method is proposed for a class of underactuated mechanical systems with two degrees of freedom. The basic principle of the proposed control scheme is to introduce a nonlinear reaching law to the control mechanism. The proposed reaching law can dynamically adapt to the variations of the system sliding surface, and it allows chattering reduction of the controlled system while keeping good performance of the controller. In the proposed control scheme, the whole system is divided into two subsystems and the first level sliding surfaces are defined for both subsystems. The second level sliding surface is defined through the combination of the first level sliding surfaces, and the equivalent control of the first level sliding surfaces is utilized to construct the sliding mode control law. The switching control is derived based on the second level sliding surface and the proposed reaching law, and then the control input of the whole system is finally obtained. The stability of the closed-loop system is theoretically analyzed, and the validity of the proposed control scheme is verified through the simulation of a cart-pole system.
出处
《控制工程》
CSCD
北大核心
2017年第9期1774-1780,共7页
Control Engineering of China
基金
辽宁省自然科学基金指导计划项目(201602379)
辽宁省教育厅科学技术研究一般项目(L2015241)
关键词
欠驱动系统
趋近律
分级滑模控制
抖振
Underactuated system
reaching law
hierarchical sliding mode control
chattering
