RGO-coated elastic fibres as wearable strain
sensors for full-scale detection of human
motions
Qing Mi , Qi Wang
1
, Siyao Zang, Guoming Mao, Jinnan Zhang and
Xiaomin Ren
State Key Laboratory of Information Photonics and Optical Communications, Beijing University of Posts
and Telecommunications, Beijing 100876, People’s Republic of China
E-mail: wangqi@bupt.edu.cn
Received 8 August 2017, revised 20 October 2017
Accepted for publication 16 November 2017
Published 5 December 2017
Abstract
In this study, we chose highly-elastic fabric fibres as the functional carrier and then simply
coated the fibres with reduced graphene oxide (rGO) using plasma treatment, dip coating and
hydrothermal reduction steps, finally making a wearable strain sensor. As a result, the full-scale
detection of human motions, ranging from bending joints to the pulse beat, has been achieved by
these sensors. Moreover, high sensitivity, good stability and excellent repeatability were realized.
The good sensing performances and economical fabrication process of this wearable strain
sensor have strengthened our confidence in practical applications in smart clothing, smart
fabrics, healthcare, and entertainment fields.
Supplementary material for this article is available online
Keywords: elastic fibres, reduced graphene oxide, wearable strain sensors, human motion
detections
(Some figures may appear in colour only in the online journal)
1. Introduction
Various wearable monitoring systems and related sensing
devices have been developed [1–7] as requirements have
increased for self-health-monitoring in the aged and over-
weight population, for exercise intensity monitoring in sports,
shape and fitness training, and in necessary human–machine
interactions. This has resulted in expectations of a higher
quality, and more efficient, daily life. Smart clothing, a form
of wearable monitoring, becomes an attractive solution as the
clothes and textiles are in direct contact with ∼90% of the
skin surface. A distinct advantage shown by smart clothing is
the ability to continuously collect data relating to human
motions from various body parts over a long period [8, 9].
Moreover, combined with wireless transmission technology,
smart clothing has great potential for use in the real-time
tracking of the location and vital signs of the wearer [10],
benefitting multifarious application scenarios in home
healthcare, mining, aviation, aerospace, and even military.
However, the reported smart clothing which usually integrates
sensors, necessary metal wires and signal processing devices
into clothing, strongly relies on the conventional micro-
electromechanical systems (MEMS)-based metal and semi-
conductor strain sensors, gradually showing the apparent
drawbacks in the detection range, stability, security, and
reliability [11, 12]. In particular, when in contact with the
human body, the level of comfort for the wearer is low,
deriving from the rigid nature of conventional strain sensors,
which limits the development of smart clothing to a certain
degree. Therefore, achieving the desired functionality without
sacrificing performance, comfort and aesthetics has been a
great challenge for smart clothing.
Recently, a novel type of smart clothing using nanoma-
terials-coated fabrics has been developed and proved to
simultaneously possess a good comfort level and an excellent
strain sensing performance [13, 14]. Graphene, one class of
Smar t Materials and Structures
Smart Mater. Struct. 27 (2018) 015014 (8pp) https://doi.org/10.1088/1361-665X/aa9aff
1
Author to whom any correspondence should be addressed.
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