直驱进给系统摩擦力特性的辨识研究

Identification of Friction Characteristics of Direct Drive Feed System

文章重点研究直驱进给伺服系统的摩擦力特性辨识问题。着重介绍了摩擦力的非线性特性,给出了其模型,定性分析其对系统的不利影响。同时,指出了在低速和高速进给时的负载力和速度对系统非线性摩檫力的作用。文章针对摩擦力非线性辨识问题,采用Var Der Pol方程求解方法进行相关分析与辨识,分析了摩擦力非线性特性的特点,给出了其非线性判据。摩擦力对系统非线性作用,主要体现在低速段,它使系统出现自激振动从而导致系统出现爬行现象,系统陷入失稳状态。负载力在高速段,对系统摩擦力的影响比较明显。通过试验,验证了摩擦力非线性特性辨识的合理性和正确性,摩擦力受速度和负载力的影响较为明显。

This paper focuses on the identification of friction characteristics of direct drive feed servo system. The nonlinear characteristics of friction force are introduced emphatically, given its model and qualitatively analyze the adverse effects on the system Meanwhlie, the role at low speed and high speed feed load force and speed of the nonlinear friction force of the system is introduced. Aiming at the problem of nonlin- ear friction identification, using Var Der Pol equation solving method is to correlate analysis and identification. The characteristics of nonlinear friction force are analyzed, and the nonlinear criterion is given. The nonlinear effect of friction force on system is obvious at the low speed and causes the system to appear the self-excited vibration thus causes the system to crawl. The influence of the load on the system friction is obvious . The rationality and correctness of the identification of nonlinear characteristics of friction force are verified by experiments. It is obvious that the friction force is affected by the speed and the load force, which provides a theoretical basis for the practical engineering.