Exploiting high frequency waves for SHM using 3D SLDV system: what can we learn more?

This research work will present a study on the use of a 3D Scanning Laser Doppler Vibrometer (3D-SLDV) to visualise the wave field in threedimensional composite structures. Knowledge of the wave field in structures, induced either actively by for example piezo-electric transducers or by an impact, supports the design of integrated Structural Health Monitoring (SHM) sensor systems on aerospace components to detect damage precursors. Reconstruction of an impact location and the possibly associated damage, may be relatively straightforward in simple geometries of homogeneous materials, whereby sensor and signal analysis are not biased by any geometrical feature other than the location of the impact and damage in the structure. The more complex the geometry, the more complex the wave field. Any additional feature to a simple geometry can bias the measurement interpretation. Understanding of the wave field is often supported by numerical models, which are also limited by these geometrical complexities. Experimental validation of the calculated wave fields is therefore of great importance. Oneof the goals of this research is to exploit the 3D-SLDV to overcome the
identified challenges. It is believed that better measurement strategies for SHM can be achieved by investigating how vibrations and acoustic waves generate and manifest in complex geometrical structures. SLDV based experimental validation is an important tool assisting the development of SHM systems in aerospace applications