Monolithic Integration of Printable PVDF-TrFE Piezoelectric Multifunctional Devices: From Sensing to Actuation

This study demonstrates the development of multifunctional printable piezoelectric actuators using PVDF-TrFE and PEDOT:PSS, capable of operating at low voltages and supporting a wide range of applications. By leveraging the high piezoelectric coefficient of PVDF-TrFE and the conductivity of PEDOT:PSS, the actuators exhibit stable performance with precise inkjet printing deposition and optimized waveform parameters. The fabrication process integrates inkjet printing and standard lithography, enabling monolithic integration for high-performance actuation and multifunctional sensing. The PVDF-TrFE-based actuators achieve low-voltage operation (as low as 50 V), efficient energy transfer, and mechanical stability. Enhancing the beta phase of PVDF-TrFE resulted in a deflection of ≈600 µm and vortex generation, crucial for lift in aerial robotic applications. Durability tests confirmed minimal performance degradation after 2,300 actuation cycles. Beyond mechanical deflection, the actuators exhibit sound detection and strain sensing capabilities. Experimental evaluations validated their ability to differentiate sound frequencies, detect muscle strain, and replicate bio-inspired flight dynamics. A preliminary proof of concept for a double-wing structure demonstrated lift generation at low voltages and resonant frequencies. The results indicate that these piezoelectric actuators are well-suited for miniaturized robotic applications, particularly in aerial locomotion and multifunctional sensing, opening new possibilities for innovations in micro-robotics, wearables, and aerial robotics.