Fabrication of Flexible Pressure Sensor Systems for Biomedical Applications

Abstract

In today s sedentary lifestyle, a person spends a substantial amount of time in a sitting position. newlineHaving a poor sitting posture can put more stress on specific muscles and joints, forcing them to be newlineoverworked and causing them to fatigue, which results in back pains. Health is Wealth and when newlinewe are talking about a healthy body, posture is as important as eating in the right way and regular newlineexercising. Hence, it is very important for us to sit in the correct posture. Incorrect sitting posture leads newlineto widespread chronic back pain and other health-related issues, particularly in young adults. newlineWe developed a flexible pressure-sensor-array-based smart chair that analyses sitting posture using newlinemachine learning algorithms. This is an add-on feature that can be installed on any existing chair or newlinecan be integrated into chairs by manufacturers. The solution is completely flexible, requires very low newlinepower, and is low-cost. The smart chair works by mapping the body pressure at the seat and the backrest. newlineMachine learning algorithms are used for the training and classification of different postures for posture newlinerecognition. newlineTo fabricate a flexible pressure sensor, we presented the synthesis of an organic polymer-polypyrrole newlineused as a piezoresistive conductive material that was synthesized using in-situ chemical oxidative liquid newlinepolymerization. The sensor showed high sensitivity at low-pressure ranges and can measure pressure in newlinethe range of 160 Pa to 16 kPa. We then presented the design of a smaller sensor array mat (4 × 4) using newlinea carbon-impregnated conductive polymer named velostat, and performed various tests to ensure that it newlinecould be effectively used for posture recognition applications. newlineWe presented the mechanical reliability of a velostat-based pressure sensor. We reported the bending newlineresponse by examining its reliability when subjected to repeated mechanical stress for 150 bending newlinecycles. We presented for the first time ever, the long-term reliability of velostat by testing it for 210 newlinedays. From the results, we ob