基于小波包能量特征向量的光纤布拉格光栅低速冲击定位

Localization of low-velocity impact by using fiber Bragg grating sensors based on wavelet packet energy eigenvector

光纤布拉格光栅(FBG)传感器在飞行器的实时冲击定位监测中具有广阔的应用前景。根据两次冲击位置距离越近接收到信号幅频特性相似度越高的关系,提出基于小波包能量特征向量与相似度匹配算法共同实现冲击定位的研究,构建了一套由光纤布拉格光栅传感器和复合材料层合板组成的冲击定位监测系统。首先通过遍布冲击建立能量特征向量数据库。然后通过试验点的能量特征向量与数据库中各点的能量特征向量进行相似度计算实现冲击定位。实验表明,对480 mm×480 mm的复合材料层合板的16次冲击定位实验中,该方法的最大误差为40 mm。

Fiber Bragg grating(FBG) sensors have great application prospects in identifying impact location on aircraft,especially for real-time monitoring. Here,a method to identify impact location was designed based on wavelet packet energy eigenvector and the similarity measurement algorithm,according to the relationships between amplitudefrequency characteristics induced by different impact locations,the closer two impact locations,the similar these two amplitude-frequency characteristics. Then,a monitor system was constructed of fiber-reinforced composite laminates and FBG sensors to verify the effectiveness of the proposed method. Initially,an energy eigenvector database was established by impacting all selected points on the laminates. Then,energy eigenvector was recorded by impacting an arbitrary position. By computing the similarity between the energy eigenvector recorded and all energy eigenvectors in database,the impact location could be determined with a tolerable error. Within 16 experiments on a 480 mm×480 mm fiber-reinforced composite laminates,the maximum error was 40 mm.