Structural Health Monitoring (SHM) focuses on developing technologies and systems for detecting and locating damages in structures such as buildings, bridges, and aerospace structures. SHM techniques typically analyze changes in the structural response induced in a structure (from before and after possible damage) due to ambient (such as heavy winds or passing vehicles) or forced (shakers and impact hammers) excitation sources to detect and locate damages.
Untethered wireless sensor network-based structural sensing can significantly drive down cabling installation and maintenance costs while allowing flexible, dense, deployments. Use of wirelessly controlled actuators at various locations in the structure, capable of delivering deterministic excitations can lead to automated SHM sensor-actuator networks that allow for very low-duty cycle operations. We envision autonomous sensor-actuator networks that test structures by periodically exciting them at pre-determined locations and analyzing the structural responses. Such sensor-actuator networks promise to bring about a fundamental paradigm shift in SHM.