"The process of monitoring involves, in effect, a wireless sensor network," Dr. Mohamed Saafi of the university's department of civil engineering said in a press release. "The paint is interfaced with wireless communication nodes with power harvesting and warning capability to remotely detect any unseen damage, such as micro-cracks in a wind turbine concrete foundation." The research team consists of Dr. Saafi and David McGahon, who initiated the work as part of his PhD project.
McGahon says energy harvesting methods might include using the vibrations of cars or trains going through a tunnel. "The idea is to make it more sustainable so you're not running out to your bridge or structure to change the battery all the time."
The research team is also examining the possibility of incorporating electrical impedance tomography technology into a structure to help locate cracks. This technology creates a conductivity map. If a change in conductivity indicates a crack, a finite element model will show the exact location within the structure.
The team has developed a prototype, and the paint/electrode combination is undergoing testing. The researchers have been trying to discover the exact percentage of carbon nanotubes needed to make the product cost-effective. They have also conducted bending tests using strain sensors. Further tests will be carried out in the next couple of months.