Design and manufacture of intelligent fabric-based insoles for disease prevention by monitoring plantar pressure

Abstract

Detecting abnormal plantar pressure as soon as possible always can be surprising. Such as diabetic foot ulcer (DFU), which has a 70%− 90% correlation with abnormal plantar pressure. Timely detection of abnormal plantar pressure means the reduction of family pressure, patient pain, and social medical. Herein, an insole based on flexible fabric sensors monitoring plantar pressure anytime and anywhere was prepared. Warp-knitted spacer fabric treated by graphene composite water-based conductive coating and filled with silicone rubber. The results show that the insole has a wide response range ( 0–100 kPa) with a 5 kPa sensitivity. Meanwhile, pressure applied on its surface with different frequencies can be distinguished in 0.7 s. These demonstrated that the insole can monitor the variation of plantar pressure and adapt to different kinds of estates. Importantly, the gauge factor (GF) is 10.693 and stays stable though the strain reaches 20%. The insole still showed good pressure sensing performance even in the simulated a high humidity environment that is much higher than the environment inside the shoe (90% humidity).