Capacitive pressure sensor inlaid a porous dielectric layer of superelastic polydimethylsiloxane in conductive fabrics for detection of human motions

Flexible, sensitive and largescale normal pressure sensors are in high demand of rapid development of healthcare and e-skin systems. In this paper, a new capacitive normal pressure sensor was fabricated based on a dielectric layer of superelastic polydimethylsiloxane (PDMS) with uniformly distributed micro-pores. The micro-pores were formed through vacuum-assisted infiltration of PDMS solution using sugar particles as porogen. Results showed that the PDMS layer with uniform micro-pores without sugar residue was successfully obtained. The developed sensor experimentally displayed a high elasticity, a large sensing pressure range ( > 200 kPa), a high sensitivity (0.023 kPa1), a good hysteresis, a fast response (about 155 ms) and a good structural stability and durability for using more than 1000 cycles. Demonstrations of the fabricated sensor in detecting finger grabbing and plantar pressure were performed, indicating it a high potential in the future use of e-skin or rehabilitation monitoring system. (C) 2020 Elsevier B.V. All rights reserved.