Additive manufacturing of piezoelectric force sensors

Piezoelectric poly(vinylidene fluoride-co-trifluoroethylene), or PVDF-trFE, has enabled unprecedented flexible and dynamic force sensors due to its mechanical robustness and biocompatibility. This study focuses on additive manufacturing of PVDF-trFE thin film sensors using an nScrypt micro-dispenser. PVDF-trFE ink composition, substrate treatment, and printer settings were first investigated to ensure consistent and uniform printing. Post-processing procedures, including curing and electrical poling, were then analyzed experimentally. The effectiveness of the manufacturing procedure was quantified in terms of piezoelectric coefficients. By using commercially-available electrically conductive silver inks, a force sensor consisting of a PVDF-trFE film sandwiched by silver electrodes were prototyped.