中文摘要：

空气静压导轨的气膜波动已成为超精密加工工件波纹度的主要影响因素。为分析空气静压导轨性能,利用雷诺方程推导出双排节流孔结构形式的空气静压导轨气膜刚度计算公式,并对相应空气静压导轨进行静态刚度检测试验以验证建立的导轨气膜刚度模型的正确性与可行性。结合静压导轨的模态分析结果,建立空气静压导轨的动力学模型。根据气浮导轨系统的动力学方程,给出气浮溜板刚度及其在加工过程中随气膜厚度变化的波动频率的仿真步骤和结果,根据引起的振动幅值分析气膜波动对加工结果的影响。利用小波变换把加工工件面形检测结果分解为各尺度下低频信号和高频信号,并把各尺度下高频信号做功率谱密度分析,从导轨气膜波动频率出发辨识出导轨气膜波动信号所在的尺度,根据相应的功率谱密度幅值推导出对加工结果的影响程度。

英文摘要：

The fluctuation of gas film of aerostatic guideway has been the main factor of the workpiece waviness in ultra-precision machining. The stiffness equation of a double row orifice of aerostatic guideway is derived by using Reynolds equation in order to analyze the performance of aerostatic guideway,the measurement experiment of corresponding static stiffness of aerostatic guideway is carried out to verify the correctness and feasibility of the established model of stiffness. Dynamic model of aerostatic guideway is established by combining the modal analysis result. The simulated results of stiffness and fluctuation frequency with the variation of thickness of gas film are obtained according to the dynamic model; the effect of fluctuation of gas film on the machining result is analyzed on the basis of the amplitude of vibration. Wavelet transform is used to decompose the measured signal of workpiece into low frequency signal and high frequency signal in every scale,and the power spectral density is used to analyze high frequency signal. Which scale the signal of gas film fluctuation lies in is identified according to the frequency of guideway system,the impact of gas fluctuation on the machining can be derived from the amplitude of power spectral density.