Bioinspired, SWCNT-Coated, Micro-Hexagonal Array Based Electronic Skin for Mechanical Sensing

Abstract

Highly sensitive, flexible electronic skins (e-skins) with multi-modal, vibration sensing ability is of great interest for various applications, such as tactile sensing in robots, earthquake monitoring, human healthcare and wearable electronics. Here, we present an e-skin based on bioinspired, micro-hexagonal pillar arrays coated with single-walled carbon nanotubes (SWCNTs). The interlocking configuration between the meshed arrays allows stable sensing performance under both static and dynamic mechanical stimuli, including pressure, shear, and bending through the piezoresistive principle. Furthermore, the optimized interlocking geometries based on micro-hexagonal pillar arrays show enhanced sensitivity and ability to differentiate various modes of mechanical loading owing to the surface contacts between the microstructures, whose contact-separation behavior depends on the type of loading. We also showed that our e-skin can detect internal and external vibrations for various applications, including earthquake monitoring, smart phone detection and voice recognition, and demonstrated that they can measure different types and intensities of vibration.