精密空气弹簧隔振平台固有频率的研究

摘要

As an important physical parameter of the air-spring isolation platform, the natural frequency also plays vital role in the evaluation of the vibration isolation transfer rate. However,whether the theoretical calculation and the experimental natural frequency accord with each other is still obscure. In order to solve this problem, the dynamic models of the air-spring isolation system are improved and the theoretical calculation natural frequency is 1.28 Hz based on an isolation system. Impact experiments are carried out in lab and the experimental natural frequency is 1.22 Hz using FFT method. The relative error between the two is less than 5 % .which reaches the expectations,and the error sources are briefly analyzed.%固有频率是空气弹簧隔振平台的重要物理参数之一,也是估计和衡量隔振系统隔振传递率大小的重要参数,但其理论计算与实际测试值的一致程度不易明确.以中国计量学院重中之重实验室的空气弹簧隔振平台为例,改进了隔振平台的动力学模型,得到了该隔振平台固有频率的理论值为1.28 Hz.然后,对实验得到的时域响应曲线进行FFT变换,得到隔振平台固有频率的实测值为1.22Hz,二者相对误差小于5％,达到了预期的研究目标.对误差的来源也进行了简要的分析.