基于小波包变换及相关系数法的复合材料层合板冲击位置识别研究

复合材料较为广泛应用于航空、航天等工程领域,但对冲击载荷十分敏感。因此,对复合材料结构承受的冲击载荷进行在线监测以及冲击位置的实时识别具有重要意义。文章以复合材料层合板为研究对象,基于两个冲击位置的距离越靠近则接收到信号幅频特性相似度越高的特点,采用FBG光纤光栅传感器,通过小波包变换的方法来提取能量特征向量,同时结合相关系数法来实现复合材料层合板的冲击位置识别。在480 mm×480 mm的复合材料层合板上开展冲击实验,8次实验皆完成了冲击位置识别,其中7个点距离误差为0 mm,实现精准识别,另一个点误差在6%以内。

The impact location identification of composite laminate based on wavelet packet transform and correlation coefficient method

Composite materials are widely used in aviation, aerospace and other engineering fields. However, composite materials are very sensitive to the impact load. In order to improve the accuracy of the impact localization identification in composite structures in real-time, it is necessary to carry out the online structural health monitoring for the impact load on composite structures. In this paper, for the composite laminate, based on the fact that the closer the two impact positions, the higher the similarity of the received signal''s amplitude-frequency characteristics. The method of the wavelet packet transform is used to extract the energy feature vector through the Fiber Bragg Grating (FBG) sensor. The correlation coefficient method is used for the impact localization identification of the composite laminate. Eight impact location identification experiments are carried out for the 480 mm×480 mm composite laminate. The localization error is zero for seven of them; and the percentage error is not more than 6% for the other one.