A Wireless Active Sensing System for Impedance-based Structural Health Monitoring

Deployment of Structural Health Monitoring (SHM) systems for permanent damage detection is limited by the availability of sensor technology. The development of a single board computer system is the focus for initial efforts in realizing a fully self-contained active sensor system utilizing impedance-based SHM. The active sensing system interrogates a structure utilizing a self-sensing actuator and the low cost impedance method, and all the data processing, storage, and analysis is performed at the sensor location. A wireless transmitter is used to communicate the current status of the structure. Piezoelectric-based power harvesting allows the sensing system to be completely self-contained and autonomous. With this new low cost, field deployable impedance analyzer, reliance on traditional expensive, bulky, and power consuming impedance analyzers is no longer necessary. Experimental validation of the prototype is performed on a representative structure and compared to traditional methods of damage detection. The benefits of this new system are discussed, along with current research and the path forward to a complete stand alone SHM system.