NANO SILVER IMPREGNATED NONWOVEN PIEZO-RESISTIVE BIO-SENSORS

Due to the increasing demand for wearable bio-signal sensors, it is necessary and important to investigate suitable flexible textile materials for sensor applications. A new type of piezo-resistive material which can be used in sensing the ballistocardiographic (BCG) signal (mechanical heart signal) and the breathing signal is presented in this paper. This novel material is based on nonwovens impregnated with silver nano particles, sandwiched in between two layers of silver knitted fabrics. The paper presents electro-mechanical characterisation by experimental results from the quasi-static and dynamic compression tests and sensor drift analysis. It is found that the thickness of the nonwoven fabric and the nano silver content on the nonwoven fabric can be engineered in such a way to get the optimum sensor performance.