Single Mode Tuning Effects on Lamb Wave Time Reversal with Piezoelectric Wafer Active Sensors for Structural Health Monitoring

Lamb wave time reversal method is a new and tempting baseline-free damage detection technique for structural health monitoring. With this method, certain types of damage can be detected without baseline data. However, the application of this method using piezoelectric wafer active sensors (PWAS) is complicated by the existence of at least two Lamb wave modes at any given frequency, and by the dispersion nature of the Lamb wave modes existing in thin-wall structures. The theory of PWAS-related Lamb wave time reversal has not yet been fully studied.