Lamb波损伤监测技术是近年来结构健康监测研究的热点之一。由于Lamb波传播过程中存在频散及多模效应,监测过程中结构响应信号十分复杂,给信号处理和分析带来困难。根据压电元件激励与传感模型,对Lamb波模式调制及选择方法进行了分析研究,给出了基于压电元件的选择性模式激励与接收原理,实现对期望模式的激发和采集,简化响应信号及后续处理。在铝板结构上的实验研究验证了方法的有效性。
Lamb wave based damage detection is one of the hot of structural health monitoring (SHM) technology in recent years. Due to the multi-mode and dispersion effects of Lamb wave, the structural responses are usually very complicated in the monitoring process which causes signal processing and analysis difficult. Based on Lamb wave actua- ting and sensing model using piezoelectric sensor, modulation of the Lamb wave mode selection method were analyzed. The principles of the selective mode excitation and collection were given. It can achieve the excitation of desired mode, and simplify the subsequent response signal processing. Experimental study on aluminum plate structure validates the effect of the method.