A Methodological Review of Piezoelectric Based Acoustic Wave Generation and Detection Techniques for Structural Health Monitoring
Figure 30
Application of a laser for ultrasonic wave generation and of a piezoelectric sensor for ultrasonic wave detection. (a) Laser ultrasonic visualization system using a dual-angle stage for scanning; (b) laser ultrasonic visualization system using a scanning mirror; (c) illustration of an image construction process: (1) one ultrasonic signal saved, (2) matrix data structure for one vertical scan, (3) raw matrix data structure for the different vertical scans, and (4) data manipulated to fit the shown structure and sliced along the time axis; (d)application example for damage detection: (1) Hammer-struck damage on a CFRP skin, (2) C-scan image, and (3) wave field propagation snapshots in the vicinity of the impact damage (dimensions in mm).
