Self-sensing and power harvesting carbon nanotube-composites based on piezoelectric polymers

Recently, the need for long-term structural health monitoring has warranted the design of novel sensing transducers. In particular, nanotechnology offers new material processing techniques that allow for novel multifunctional thin film sensor designs which combine sensing, actuation, and power harvesting into one platform. In this study, single-walled carbon nanotubes (SWNT) are used as filler material to tailor the sensing and power harvesting performance of poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] nanocomposites. SWNT-P(VDF-TrFE) thin films fabricated via a thermal evaporation and annealing procedure are shown to exhibit high mechanical strength and deformation tolerance. Furthermore, capacitive strain sensors exhibit high capacitive-strain sensitivities. When coupled with a passive wireless radio frequency identification system, these capacitive strain sensors cause detectable changes the system resonant frequency during applied strain. Finally, the potential for harvesting power from ambient structural vibrations is validated. 3329 Bridge Maintenance, Safety, Management, Health Monitoring and Informatics – Koh & Frangopol (eds) © 2008 Taylor & Francis Group, London, ISBN 978-0-415-46844-2