TY - JOUR
T1 - The effect of dual-scale carbon fibre network on sensitivity and stretchability of wearable sensors
AU - Zhang, Fan
AU - Wu, Shuying
AU - Peng, Shuhua
AU - Wang, Chun H.
PY - 2018/9/8
Y1 - 2018/9/8
N2 - Sensitivity and stretchability are two key characteristics of wearable sensors and tactile sensors for soft robotics. Here, we present a new technique to increase the sensitivity of wearable sensors by creating a conductive network of dual-scale carbon fibres, i.e., carbon nanofibres (CNFs) and short carbon fibres (SCFs), in a polydimethylsiloxane (PDMS) matrix. To quantify the effects of this dual-scale carbon fibre network on the stretchability, sensitivity, and stability under repeated loading, comprehensive experiments were conducted to characterise the electrical conductivity, mechanical properties, and piezoresistivity of the resultant PDMS composites with varying concentrations of carbon fibres. The Prony series model of viscoelasticity was adapted to model the strain-rate dependent behaviour of the new sensors. The results reveal that this dual-scale network is able to significantly lower the percolation threshold below that of either of the single-scale composites containing only SCFs or CNFs, indicating a strong synergistic effect. Furthermore, the dual-scale carbon network exhibits higher piezoresistive sensitivity than the CNF-reinforced composite while retaining similar stretchability, thus offering a new technique for creating highly sensitive wearable sensors and tactile sensors for soft robotics.
AB - Sensitivity and stretchability are two key characteristics of wearable sensors and tactile sensors for soft robotics. Here, we present a new technique to increase the sensitivity of wearable sensors by creating a conductive network of dual-scale carbon fibres, i.e., carbon nanofibres (CNFs) and short carbon fibres (SCFs), in a polydimethylsiloxane (PDMS) matrix. To quantify the effects of this dual-scale carbon fibre network on the stretchability, sensitivity, and stability under repeated loading, comprehensive experiments were conducted to characterise the electrical conductivity, mechanical properties, and piezoresistivity of the resultant PDMS composites with varying concentrations of carbon fibres. The Prony series model of viscoelasticity was adapted to model the strain-rate dependent behaviour of the new sensors. The results reveal that this dual-scale network is able to significantly lower the percolation threshold below that of either of the single-scale composites containing only SCFs or CNFs, indicating a strong synergistic effect. Furthermore, the dual-scale carbon network exhibits higher piezoresistive sensitivity than the CNF-reinforced composite while retaining similar stretchability, thus offering a new technique for creating highly sensitive wearable sensors and tactile sensors for soft robotics.
KW - PDMS composites
KW - Dual-scale carbon fibres
KW - Sensitivity
KW - Stretchability
KW - Wearable sensors
UR - http://www.scopus.com/inward/record.url?scp=85048974896&partnerID=8YFLogxK
UR - http://purl.org/au-research/grants/arc/DE170100284
U2 - 10.1016/j.compscitech.2018.06.019
DO - 10.1016/j.compscitech.2018.06.019
M3 - Article
VL - 165
SP - 131
EP - 139
JO - Composites Science and Technology
JF - Composites Science and Technology
SN - 0266-3538
ER -