A novel passive embeddable RF sensor for structural health monitoring

A present challenge in structural health monitoring consists in the detection, localization, and quantification of small damage (e.g., small cracks) within large structures, such as bridges and buildings. Existing sensing solutions have several limitations, the most important being those related to the extent of spatial coverage by sensors and power supply. In this work, we will present proof-of-concept research for sub-millimeter displacement measurement using novel embeddable passive wireless radio frequency (RF) sensors. The novel sensors estimate relative displacement from phase shifts in the transmitted RF signal. The proposed system represents a novel paradigm in wireless sensing in structural health monitoring, as the wireless sensors are battery-less and will be deployed in a form of densely populated 3D network embedded within large volume of material.