一种低频水平振动激励系统的设计与试验

Design and Test of a Low Frequency Horizon Vibration Platform

设计了一种使用方便、结构简单并具有1.2米行程的低频激振测试系统。该系统能够通过伺服控制模拟正弦速度曲线、半正弦速度曲线、梯形速度曲线、阶跃等运动形式,可在一定的频率范围内实现扫频。该系统的长行程可以弥补普通电磁激振台的低频运动失真的不足。样机测试显示,系统在较高速度下运动,可以得到较为理想的运动曲线,随着速度的降低,曲线误差逐渐增大,原因在于运动受导轨的库伦摩擦影响较大,需要在控制算法和减小摩擦方面进行完善。

A vibration platform was designed and fabricated, which was characterized with a simple structure, convenience for use and a 1.2m length of travel. The system can simulate the sinusoidal velocity curve, half-sine velocity curve, trapezoidal velocity curve, step and other fomas of movement. Otherwise, it can achieve sweeping frequency to some extend. The long length of travel of the system can make up for the distortion of the velocity of ordinary low-frequency electromagnetic vibration tables. The prototype tests show the better velocity curve when the system runs at the higher speed. By contraries, the velocity curve distorts with the decrease of velocity. The distortional curve arises from the Coulomb friction of guide rail. With the improvement of the control algorithms and the decrease of friction force, the distortion will be reduced effectively.