Abstract:

It is difficult to identify the torsional vibrating modes of ball screw feed drive systems, a new measuring and analysis method was proposed herein, which involved several straightforward steps. Firstly, a high-resolution rotating encoder was installed at the end of the screw,and the high-speed counting cards were then used to measure the acceleration signals intercepted by this encoder and the inbuilt one attached to the servo motor respectively. The signals were further analyzed in the frequency domain. The analysis results were subsequently used to fine-tuning the numerical calculation based on a finite-element and lumped-parameter model built for simulating the ball screw feed drives, which finally allowed recognition of the natural torsional vibration frequencies and corresponding mode shapes. The case study presented herein shows that the proposed method can be used to precisely estimate the first and second order torsional vibration natural frequencies and corresponding mode shapes of a ball screw feed drive system effectively.

Key words: ball screw, torsional vibration, finite element method, measurement

摘要：

针对滚珠丝杠副驱动机构的扭转振动模态难以通过测量多点激励-响应的方式进行测量的问题，提出了一种新的测量与分析方法：在丝杠尾端安装高分辨率旋转编码器，利用高速计数卡分别测量该编码器及伺服电机码盘的角加速度信号，并进行频域分析;根据所建立的滚珠丝杠副驱动机构有限元-集中参数模型，通过数值计算并结合实验测量结果获得其扭转振动固有频率和振型。实例研究表明，所提出的测量和分析方法可精确获得驱动机构扭转振动模态的前两阶固有频率和振型。

关键词: 滚珠丝杠, 扭转振动, 有限元, 测量