小波分析在飞机振动飞行测试数据分析中的应用

Application of wavelet analysis in airplane vibration flight test data analysis

目前,飞机振动飞行测试数据分析主要采用基于Fourier理论的频域分析方法,无法描述振动信号的时频局部特性,很难满足飞机振动评估的需要。引入小波分析理论,在时域内对信号进行离散变换,在频域内对信号进行谱分析,从而达到同时观察信号在时域和频域空间分布特征的目的。两种飞机典型振动飞行测试数据的时频分析结果表明,利用小波理论能够更好地观察机体振动在时域、频域内的局部特性,对于现代飞机振动问题的分析评估具有重要意义。

At the present time,flight test data is used for frequency domain analysis based on Fourier theory. It cannot describe the local time-frequency characteristic of vibration,and is hard to meet the needs of airplane vibration evaluation. For airplane vibration signals in flight,it was necessary to introduce the wavelet analysis theory for discrete transform in time domain and spectral analysis in frequency domain.So distribution characteristics of time domain and frequency domain were observed at the same time. According to the analysis results of a light plane and a large plane in typical flight states,airplane vibration local characteristics were better described using wavelet analysis theory in time domain and frequency domain. The research results are of great significance to airplane vibration evaluation.