动态摩擦模型仿真

为了深入分析摩擦力动态特性在高精度的伺服系统控制中造成的影响,检验摩擦补偿方法对动态摩擦的补偿效果,需要建立一个有效的动态仿真摩擦模型。如今摩擦的仿真研究都局限于非线性静态模型的实现,而对于微分方程描述的动态模型,还没有有效的实现方法。尤其是系统启动时,静摩擦给系统造成的小误差观察不到。基于动态刚毛摩擦模型,通过定义“粘滞”和“滑动”两个状态,成功地模拟出摩擦在启动和制动时对系统的不同影响。在跟踪正弦轨迹的误差仿真结果中可以观察到:速度转向时摩擦造成了启动小误差,与实际情况一致。这种处理方法适用于微分方程描述的动态摩擦模型,同样可以用于代数方程描述的静态模型仿真。

A Simulatoin Method for Dynamic Friction Model

In order to analyze the result caused by the frictional dynamic character in servo system,and test the validity of various friction compensation methods,a simulation scheme for dynamic friction model is required.Although simulation methods for nonlinear static friction model have been brought forward,there isn't any effective method to simulate dynamic model up to the present.It means that the glitch caused by static friction at velocity reversals can't be observed in simulation.Different affections of friction at starting and stopping are distinguished by dividing the movement of the system into two proceedings-stick and slip.In the simulation,a servo system is conducted to follow a sinusoidal signal,where friction force is expressed by LuGre friction model.The glitch caused by friction at reversals is observed in the simulation result,which is consistent with the reality.This method can also be applied to other dynamic models and static models.