Experimental Study of Flexible Pressure Sensor via Direct Writing

doi:10.3901/JME.2019.11.090

Abstract

Abstract: Flexible pressure sensors are crucial building blocks for potential applications including intelligent robots and biomedical engineering. According to its demand of high resistivity, good pressure resolution and fast response for sensing medium pressure between 10 kPa and 50 kPa, a flexible pressure sensor is fabricated by direct writing graphene nanoplatelets (GNPs)/multi-walled carbon nanotubes (MWCNT) composite on a PDMS substrate to construct an S-shape sensing element, together with a microstructure-arrayed package component. Experiment results show that its sensitivity is about 0.114 kPa^-1 and 1.41 kPa^-1, under pressure of 0-15 kPa and 15-40 kPa respectively. Its response/recovery time is about 100/50 ms, which is faster than that of most medium pressure sensors. It also can sense subtle pressure change about 3 Pa. It is characterized to be of better repeatability and cycling stability. At the same time, the different phonation can be accurately distinguished and recognized by the sensor, and the different finger pressure signals can be accurately and stably feedback. Thus, such sensors will offer a possible optimized choice for speech recognition, artificial limb, fabrication of electronic skins and medical rehabilitation devices with high performance.

Key words: direct write, electronic skins, flexible pressure sensor, graphene nanoplatelets, microstructures

CLC Number:

TP212

LUO Yihui, PENG Qianqian, ZHU Yuchao, WANG Guangshun, WU Dezhi, ZHU Rui, XIE Yu, SUN Daoheng. Experimental Study of Flexible Pressure Sensor via Direct Writing[J]. Journal of Mechanical Engineering, 2019, 55(11): 90-97.

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