Optimization of PVDF nanocomposite based flexible piezoelectric tactile sensors: A comparative investigation

A comparative analysis of the performance enhancement of PVDF-based piezoelectric tactile sensors with the addition of different nanofillers is presented. Zinc oxide, titanium dioxide, and nanosilica fillers were selected to develop PVDF composite sensor films. A series of tests were performed on the nanocomposites to evaluate the electrical, thermal, and mechanical properties. The incorporation of nanofillers leads to faster crystallization and thereby promotes strong interfacial interactions leading into the formation of piezoelectric β-phase enriched PVDF composites. Process flow involved in the fabrication, packaging and characterization of the piezoelectric nanocomposite based tactile sensors are discussed in detail. The sensor characterization results show that nanoparticle addition into the PVDF matrix improves the piezoelectric performance with a maximum observed sensitivity of 103 mV/N for zinc oxide incorporated devices. The sensors developed with titanium dioxide and nanosilica particles also exhibited a similar improvement in the sensitivity. Flexible, and self-powered tactile sensors were realized using cost-effective fabrication mechanisms which are targeted towards implementing in the large area portions of prosthetic devices.