气浮导轨解耦结构振动传递特性分析

Analysis of Vibration Transmission Characteristics of Aerostatic Guide Decoupling Structure

三轴振动激励器各轴分别设置的气浮导轨解耦结构不仅要对非轴向运动实现润滑导向,还需将自身轴的运动传递到三轴运动平台(输出振动激励信号)。为提高振动传递精度,基于解耦结构的单轴等效模型,探究气浮导轨的轴向振动传递特性与自身工作参数的关系;基于对局部多孔质气浮导轨气膜压力、承载力及刚度等特性的计算及仿真分析,得到其结构和工作参数变化对振动传递率的影响规律,进而实现解耦结构的优化设计,提高三轴振动激励信号的解耦精度。

The aerostatic guide decoupling structure for each axis of the tri-axial vibrator can not only lubricate and guide non-axial movement,but also transfer self-axis motion to tri-axial motion platform(output vibration excitation signal).In order to improve vibration transmission accuracy,firstly the relationship between the axial vibration transmission and working parameters is studied based on a uniaxial equivalent model of the aerostatic guide decoupling structure.Based on calculation and simulation of the gas film characteristics for a partial porous aerostatic guide,such as pressure,load capacity and stiffness,the influence mechanism of the structural and working parameters on vibration transmission rate was obtained.At last,the decoupling structure optimal design and decoupling precision improvement are realized for the tri-axial vibration excitation signal.