Damage Monitoring in Realistic Structures Using Lamb Waves

This paper describes a technique, quantifying the differences in waveforms between damaged and undamaged states to measure damage severity. The technique has been verified experimentally and demonstrated promise in detecting and quantifying subsurface defects. Finite element analysis (FEA) has been performed alongside as a valid model may avoid time consuming and expensive experiments. Testing is first performed on a simple flat plate and a realistic wing skin structure with geometry such as stiffening ribs. This revealed geometry will alter the regions of scatter which leads queries over optimal sensor location. It was also discovered actuator location may not necessarily be intuitive. The comparisons made here show that implementation of an ISHM system on real world subjects is feasible despite added complexity.