On the processing of leaky guided waves propagating in immersed plates

摘要

We present a non-destructive inspection method for the structural health monitoring of underwater structures. A laser operating at 532 nm is used to excite leaky guided waves on an aluminum plate immersed in water. The plate has a few artificial defects namely vertical notch, horizontal notch, corrosion, and small hole. An array of five immersion transducers arranged in half-circle is used to detect the propagating waves. A signal processing technique is implemented to assess the presence of damage; the method is based on continuous wavelet transform to extract a few damage-sensitive features fed to an artificial neural network for damage classification. The experimental results show that the proposed system can be employed for the inspection of underwater plates.