CAJ | 학술논문

针对摩擦力给气动比例系统带来的稳态误差和低速爬行问题,从实用角度来探索解决非线性摩擦力补偿的方法.基于粘弹性理论及Stribeck模型建立气动比例系统的摩擦数学模型.将该摩擦模型引入阀控缸系统的动态模型中,建立完整的系统运动模型.将高频低幅颤振信号叠加于系统中,对系统的摩擦机理变化以及稳定性的影响进行分析.理论分析表明,叠加合适的颤振信号后,系统的部分静摩擦力转化为动摩擦力,最大静摩擦力减小,响应速度提高,从而将系统的粘滑运动转换为一种平稳运动.试验发现,当颤振信号频率为系统固有频率的3.3倍,系统的定位精度由原来的0.516 mm提高到0.284 mm,滞后时间由原来的0.17 s缩短为0.02 s.证明对气动比例系统提出的摩擦颤振补偿理论是正确的.
침대마찰력급기동비례계통대래적은태오차화저속파행문제,종실용각도래탐색해결비선성마찰력보상적방법.기우점탄성이론급Stribeck모형건립기동비례계통적마찰수학모형.장해마찰모형인입벌공항계통적동태모형중,건립완정적계통운동모형.장고빈저폭전진신호첩가우계통중,대계통적마찰궤리변화이급은정성적영향진행분석.이론분석표명,첩가합괄적전진신호후,계통적부분정마찰력전화위동마찰력,최대정마찰력감소,향응속도제고,종이장계통적점활운동전환위일충평은운동.시험발현,당전진신호빈솔위계통고유빈솔적3.3배,계통적정위정도유원래적0.516 mm제고도0.284 mm,체후시간유원래적0.17 s축단위0.02 s.증명대기동비례계통제출적마찰전진보상이론시정학적.
In order to overcome steady-state error and low-speed creeping problems caused by friction in pneumatic proportional systems,nonlinear friction force compensation method is adopted. A Friction model of the pneumatic proportional system is constructed on the basis of viscoelastic theory and Stribeck model. Incorporating the friction model in dynamical model of valve-controlled cylinder system constructs a complete system motion model. The high-frequency low-amplitude chatter signal is introduced into the system to analyze its influence on the system friction mechanism and stability. The results show that a part of static friction is turned into dynamic friction,the maximum static friction is reduced and the response speed is raised. Consequently,the stick-slip motion is transformed into a steady one by adding proper chatter signal. The experimental results show that the positioning precision is improved from 0.516 mm to 0.284 mm,and the hysteresis time is shorten from 0.17 s to 0.02 s when the chatter frequency is 3.3times of the natural one. The results prove that the friction chatter-compensation theory proposed for the pneumatic proportional system is correct.