Highly Sensitive and Stretchable Multi-dimensional Strain Sensor with Pre-strained Anisotropic Metal Nanowire Percolation Networks

Abstract

Novel designs for flexible strain-gauge sensors have been widely reported, yet remained unsuccessful in distinguishing complex characteristics of the multi-dimensional strain. Here, to overcome the limitation of the conventional single axis-strain sensor, we demonstrate a multi-dimensional strain sensor composed of two layers of pre-strained silver nanowire percolation network with decoupled and polarized electrical response in principal and perpendicular directional strain. The information on the magnitude and effective direction of surface strain are successfully calculated up to 35 % maximum strain. At the same time, the fabricated multi-dimensional sensor exhibits a markedly large gauge factor (>20) at excellent agreement with a model predicted by 3D percolation theory. The potential of the proposed sensor as a versatile wearable device has been further confirmed through its implementation as a large-area multi pixel strain sensor array on a human hand and a remote controller for an artificial 3D simulation model.