压电阵列Lamb波损伤监测信号一致性补偿方法

Lamb波结构损伤监测是结构健康监测领域的研究热点之一。针对基于压电阵列的Lamb波损伤监测研究中因传感器性能差异引起的信号偏差问题,通过分析Lamb波信号的激励、传播和传感过程,利用压电阵列中等距离传播通道直达波传递函数相同的特点,提出了窄带激励下的压电传感器机电耦合系数归一化补偿,实现对结构响应信号的一致性补偿。实验验证表明,该方法能在一定程度上抑制因压电传感器性能差异引起的信号偏差,提高了监测结果的准确性。

Signal Consistency Compensation Method for PZT Array and Lamb Wave Based Damage Monitoring

The Lamb wave based damage monitoring techniqe was one of the research focuses in structural health monitoring (SHM). In the light of the problem of signal difference caused by sensor performance deviation in PZT array and Lamb wave based damage monitoring, the actuation, propagation and sensing processes of the Lamb wave were analysed. According to the characteristic that the propagation chanels with the same distances have the same direct wave transfer functions,a new PZT sensor electromechanical coupling coefficient compensation method was proposed for consistency compensation of the structural response signals. The experimental validation indicated that the new method could suppress the signal deviation caused by the difference of the performance of the piezoelectric sensor to a certain and improve the acurrcy of the monitoring results.