Rapid Fabrication of Soft Strain Sensors by Multi-Nozzle Electrohydrodynamic Inkjet Printing for Wearable Electronics

Abstract

Soft wearable strain sensors having high sensitivity along with high deformability have been actively investigated. However, their facile and mass-production at a lower cost remains a challenge. This paper presents the rapid fabrication of soft resistive strain sensors by multi-nozzle electrohydrodynamic (EHD) inkjet printing technique. printing head comprises of five needles with discrete counter/ground electrodes is used for simultaneous printing of silver nanoparticle ink on prestrained thermoplastic polyurethane (TPU) substrate. By means of this approach, soft circuits with diverse working strain ranges are realized and tested. As an application, a soft strain sensor based on the multi-nozzle EHD printed circuit is employed for monitoring the human motion (finger bending), demonstrating the potential applications of these circuits in soft wearable electronic devices and soft human-machine interfaces.