Passive Impact Location Estimation Using Piezoelectric Sensors

As part of Structural Health Monitoring (SHM), the history of a structure has become a crucial element to take into account. This has been shown, for example, by the spectacular accident of the flight Aloha 243 near Hawaï, when a whole part of the fuselage of a Boeing 737 had been torn off. Thus, monitoring impacts has become particularly interesting to give a comprehensive view of the occurrence of structural damage. Typical impact location estimation techniques use structural frequency drifts of a structure. Thus, such methods need an external excitation of the structure, which is unrealistic in most of the cases. As well, huge and possibly long computations, as genetic algorithms or artificial neural networks, are required for such techniques in order to retrieve the impact location. The scope of the this article was to present a passive impact location estimation using piezoelectric elements for a 1D infinite beam. The principles of the proposed technique was the comparison of the vibrational energy extracted by each sensor. From this comparison, the impact location was cost-efficiently estimated. Theoretical development and experimental results showed that this extraction-based force location estimation method performed well, while being very simple.