Wearable skin sensor using programmable interlocking of nanofibers

Abstract

We presents a highly sensitive, flexible, multiplex strain gauge sensor by utilizing single active layer of nanoscale mechanical interlocking between high aspect-ratio Pt-coated polymeric nanofibers. The sandwich-assembled, interconnected nanofibers supported on thin polydimethylsiloxane (PDMS) layers displayed a specific strain gauge (GF) factors for multiplex sensing such as pressure, shear force, and torsion, measured from the change of electrical resistance as a function of applied compressive strain (≤5%). The assembled device was used to monitor continuous kinetic motion of a bouncing micro-droplet on a superhydrophobic surface and physical force of a heartbeat under different conditions. In order to enhance adaptability on exquisite human-skin, skin adhesive patches for in vitro diagnostic device are developed.