Appropriate inspections can extend the lifespan of structures and reduce the risk of catastrophic failures. Piezoelectric sensors have been widely used for structural health monitoring and nondestructive evaluation. However, a single piezoelectric sensor has limited acousto-ultrasonic coverage, and multi-channel sensors require bulky cabling and channeling devices in the case of inspecting wide area. This thesis presents a serial-connected piezoelectric sensor array connected to conductive fabric tape for damage diagnosis on wide area using the ultrasonic propagation imaging system. Using the conductive fabric tape for installation of sensor network provides convenient and compact installation, light weight, and comparatively low attenuation, compared with the lead wire. An aluminum plate with various artificial damages was tested with the proposed sensor array combined with an ultrasonic propagation imaging system. The sensitive areas of the serially connected piezoelectric sensors, were stimulated by the ultrasonic propagation imaging system. All damages were visualized in the form of the anomalous waves by the multi-wave propagation sources which covered wide area. Consequently, multi-cabling and multi-channeling are not required due to serial connections using conductive fabric tapes. Furthermore, the proposed sensor network can detect the damages successfully because of the multi-source wavefield generating capability of the ultrasonic propagation imaging system. Therefore, compact and easy installation of the sensor network with light-weight for damage detection on wide area becomes possible. Lastly, the fuselage side skin with various artificial damages of Cessna-150, the real metallic aircraft, was tested with the proposed inspection method using the ultrasonic propagation imaging system. The ultrasonic wave propagation imaging showed multi-source wave propagation scattering waves in all damages. The inspection method of this thesis shows feasibility for managing wide area of the full-scale structures.
Key Words : Single channel sensing, conductive fabric tape, piezoelectric, ultrasonic propagation imaging system