A Highly Aligned Nanowire‐Based Strain Sensor for Ultrasensitive Monitoring of Subtle Human Motion

Abstract

Achieving highly accurate responses to external stimuli during human motion is a considerable challenge for wearable devices. The present study leverages the intrinsically high surface‐to‐volume ratio as well as the mechanical robustness of nanostructures for obtaining highly‐sensitive detection of motion. To do so, highly‐aligned nanowires covering a large area were prepared by capillarity‐based mechanism. The nanowires exhibit a strain sensor with excellent gauge factor (≈35.8), capable of high responses to various subtle external stimuli (≤200 µm deformation). The wearable strain sensor exhibits also a rapid response rate (≈230 ms), mechanical stability (1000 cycles) and reproducibility, low hysteresis (<8.1%), and low power consumption (<35 µW). Moreover, it achieves a gauge factor almost five times that of microwire‐based sensors. The nanowire‐based strain sensor can be used to monitor and discriminate subtle movements of fingers, wrist, and throat swallowing accurately, enabling such movements to be integrated further into a miniaturized analyzer to create a wearable motion monitoring system for mobile healthcare.

Recent Advances in Vertically Aligned Nanowires for Photonics Applications

“…In recent years, nanowires originated from a wide variety of materials have arisen as a centerpiece for optoelectronic applications such as sensors, solar cells, optical filters, displays, light-emitting diodes and photodetectors [1][2][3][4][5][6][7][8][9][10][11][12]. Tractable but outstanding, optical features of nanowire arrays achieved by modulating its physical properties (e.g., diameter, height and pitch) allow to confine and absorb the incident light considerably, albeit its compact configuration.…”

Nanowire‐Based Soft Wearable Human–Machine Interfaces for Future Virtual and Augmented Reality Applications

“…Recently, nanowire‐based strain gauges have drawn considerable research attention owing to their excellent conductivity, stretchability, and flexibility. [ 56,83,87,88,99,102–105 ] As shown in Table 1 , many studies have reported nanowire‐based strain gauges for monitoring human motions between 2015 and 2020. These applications can be categorized into nine types based on the type of motion it monitors: facial, throat, neck, body posture, elbow/knee, wrist, opisthenar, finger, and foot.…”

Evolving Flexible Sensors, Wearable and Implantable Technologies Towards BodyNET for Advanced Healthcare and Reinforced Life Quality

“…In addition to the minor muscle movement, strain sensors are also applicable in monitoring body motions such as dynamic joint bending sensing [115]- [118]. The quantitative motion analysis could assist monitor motor disorders such as Parkinson's disease, showing great potential in diagnostics and assessment of motor neuron diseases [119].…”