基于匹配追踪的蜂窝夹层复合材料损伤检测

Research on honeycomb sandwich composite structure damage detection based on matching pursuit method

基于Lamb波和匹配追踪时频分析方法,提出一种损伤成像方法,对蜂窝夹层复合材料结构进行损伤监测。首先针对Lamb波传播的特点,提出了匹配追踪方法的快速实现方案,该方法能准确地匹配失真变形的窄带脉冲信号,并识别Lamb波的模态;然后对由压电传感器采集到的Lamb波信号,采用匹配追踪方法提取特征信息,得到Lamb波的能量分布;在此基础上,考虑Lamb波在各向异性结构中传播速度的影响,将损伤处的散射波能量分布和各像素点对比度联系起来,得到损伤图像,将损伤的情况可视化。通过蜂窝夹层复合材料结构实验验证了该方法的可行性和有效性。

This study proposes a damage imaging method using Lamb wave and matching pursuit method time-frequency analysis for damage detection of honeycomb sandwich structure.Matching pursuit method is employed to decompose Lamb wave signals into a linear expansion of several chirplet atoms using a fast realization algorithm.The relationship between Lamb wave＇s dispersion and the chirplet＇s chirp rate is established,which can be used to identify the modes of Lamb waves.Then the matching pursuit method is applied to the Lamb wave signals excited and sensed by piezoelectric sensors in the time-frequency domain,which can obtain the energy distribution of the scattered waves.Considering the effect of anisotropic property on the velocity distributions of Lamb waves,the damage image can be obtained by the time-dependent energy distribution of scattered waves.The effectiveness and accuracy of the proposed method in identifying the modes and in locating defects are demonstrated by the experimental results on the honeycomb sandwich composite structure.