Durability and Survivability of Piezoelectric Wafer Active Sensors Mounted on Aluminum Structures for Aerospace Vehicle

Electromechanical (E/M) impedance method is emerging as an effective and powerful technique for structural health monitoring (SHM). The electrical impedance of a PZT sensor can be directly related to the mechanical impedance of a host structural component where the PWAS is attached. Through piezoelectric wafer active sensors (PWAS) permanently attached to the structure, the E/M impedance method is able to measure directly the high-frequency local impedance spectrum of the structure. The high-frequency local impedance spectrum is much more sensitive to incipient damage than the low-frequency global impedance. This feature makes the E/M impedance method well suited fo