Inductance-based Flexible Pressure Sensor for Assistive Gloves

This paper presents an inductance-based flexible pressure sensor to support the tactile communication between deafblind people. The pressure sensor was realized with a soft ferromagnetic elastomer and a 17 mu m-thick coil fabricated on a 50 mu m thick flexible polyimide sheet. The ferromagnetic elastomer acts as the core of the coil, which when pressed, sees the metal particles moving closer to each other and leads to changes in the inductance. The coil, with 75 mu m wide wires and 25 mu m pitch, was realized using LIGA (Lithographie Galvanoformung, Abformung) micro molding technique. Four different sensors have been fabricated using different ratios (1:1, 2:1, 3:1 and 5:1) of ecoflex and iron nanoparticles. The results show that the higher the ratio the better the response of the sensor. The presented sensor is intended to be integrated in a smart glove having dual function of tactile sensing and vibrotactile feedback.