摘要
由于摩擦会引起气动位置伺服系统的动态滞后,尤其是气缸活塞在换向过程中容易产生"平顶"现象,因此需要对气动系统进行摩擦补偿。但是由于气动系统本身的参数不确定性和强非线性会影响摩擦补偿的效果,同时气缸两腔耦合与流量饱和会导致控制系统的自由度不高且能量损失较大。针对以上问题,文中采用表征摩擦动态特性良好的LuGre模型来描述气缸摩擦并提出了一种自适应鲁棒控制器进行摩擦补偿,控制器的自适应部分用于控制参数不确定性,鲁棒控制部分用来处理系统的非线性。同时采用两个三位四通比例阀来提高控制自由度并降低能量耗散。仿真结果表明:该补偿策略有效改善了摩擦带来的动态滞后,提高了系统的响应速度与跟踪精度。
Because the pneumatic position servo friction will cause the dynamic hysteresis of the system,especially the cylinder piston is prone to“flat top”phenomenon in the commutation process,so it is necessary to compensate the friction for the pneumatic system.However,due to the parameter uncertainties and strong nonlinearities of the pneumatic system,the effect of the friction compensation will be reduced.System is subjected to coupling of the two chambers of the cylinder and saturation of gas flow,which will cause the control system to have a low degree of freedom,and a large energy loss.In response to the above problems,the LuGre model is used to characterize the friction dynamics well,to describe the cylinder friction and propose an adaptive robust controller for friction compensation.The adaptive part of the controller is used to control parameter uncertainties.The robust part is used to deal with the nonlinearities of the system.Two three-position four-way proportional valves are applied to increase the control degrees of freedom and reduce the energy dissipation.The simulation illustrate that the compensation strategy effectively improves the dynamic lag,and improves the dynamic response and tracking accuracy of the system.
作者
魏琼
陆浩
刘伟恒
郭川
李秀红
WEI Qiong;LU Hao;LIU Weiheng;GUO Chuan;LI Xiuhong(School of Mechanical Engineering,Hubei University of Technology,Wuhan 430068,China)
出处
《机械科学与技术》
CSCD
北大核心
2023年第10期1609-1616,共8页
Mechanical Science and Technology for Aerospace Engineering
基金
国家自然科学基金项目(51905159)
湖北省重点实验室开放基金项目(KFJJ-2020005)
关键词
摩擦补偿
动态滞后
气动位置伺服
自适应鲁棒
双阀
LUGRE模型
friction compensation
dynamic hysteresis
pneumatic position servo
adaptive robust
dual valve
LuGre model
