Corrosion monitoring using a new compressed sensing-based tomographic method.

Corrosion damage of aircraft structures can significantly reduce the structural performance and endanger flight safety. There is a pressing need for research on aircraft structural corrosion monitoring technology. Lamb wave tomography (LWT) can be used to evaluate structural corrosion. However, the conventional tomographic method needs sensors with dense array, which is not easy to be satisfied in practice and limits its application. Due to the sparsity of corrosion damage in aircraft structures, compressed sensing (CS), which is an emerging signal processing technique, can be employed to optimize LWT. This paper presents a novel CS-based tomographic method to map out the internal situation of aircraft structure. Compared to conventional LWT, the CS-based tomographic method requires fewer sensors to detect the same corrosion damage while the imaging quality still maintains. The experimental study is carried out to diagnose the real corrosion damage by the new approach. Results show the advantages of the proposed CS-based tomographic method.