运动副摩擦参数的识别方法研究

Identification Methods of Friction Parameters in Kinematical Joints

采用粘性+库仑摩擦模型建立了单自由度回转机械系统运动微分方程,分别从时域和频域角度提出了两种识别运动副摩擦参数的方法。仿真结果表明,两种方法在较高信噪比下均能有效地辨识出库仑摩擦和粘性摩擦参数,其中频域法比时域法具有更高的参数估计精度。对电机驱动的单自由度转动机械系统实验装置的运动副建立了相应的摩擦模型,实验结果表明:在不同试验条件下两种方法计算得到的库仑和粘性摩擦参数具有较好重复性,从而验证了本文参数辨识方法的正确性。

Viscous plus Coulomb friction model is employed to construct the differential equation of SDOF rotary mechanical system.Two methods are presented for simultaneous identification of Coulomb and viscous parameters in view of time-domain and frequency-domain respectively.The simulations show that the identification accuracy of the frequency-domain method is higher than that of the time-domain method for the reason that the time-domain method is liable to be affected by noise.The corresponding friction model for kinematical joints of a SDOF rotary mechanical system driven by motor is established.The experimental results illustrate that the identified values of the friction parameters have satisfied repeatability under different experiment conditions.