Fully 3D printed piezoelectric pressure sensor for dynamic tactile sensing

Multi-material additive manufacturing using direct ink writing is a versatile and resource-efficient technique which can lead to low-cost sensors and embedded electronic systems. Such an approach can be used for the fabrication of multiple sensor devices promptly with minimal variation. In this work, we present a fully printed and packaged piezoelectric sensor using P(VDF-TrFE)-BaTiO3 as the active material. Sensors with different concentrations of BaTiO3 filler were fabricated to demonstrate the application of presented approach to print the devices with optimised performance. The 3 wt. % filler loading generated the highest voltage output of 3 V (at 30kPa) due to higher β-phase content as confirmed by FT-IR. The device exhibited a linear response in the working range of 0–60 kPa and remained stable under continuous operation for 2200 s. The repeatability of the fabrication approach was confirmed by fabrication of 3 devices which showed negligible variation in the output. Finally, to demonstrate the potential use in real application, the sensor was attached to a prosthetic hand and used to identify objects with different hardness based on the dynamic tactile data.