Inkjet-Printed ON/OFF Force Sensor on Flexible Substrate for Ultra-Low Power Applications

摘要

An ON/OFF force sensor is fabricated by inkjet-printing process on flexible substrates. The goal is to obtain two distinct impedance states respectively to the applied force in order to be easily identifiable by a conditioning electronics for ultra-low power applications, and to avoid the use of an analog-to-digital convertor (ADC) in particular. The sensor is composed of two electrodes separated by a spacer. The elastomer layer constituting the spacer is in polydimethylsiloxane (PDMS). An opening is created in this spacer between the two electrodes in order to define an active area. The force is applied perpendicularly to the surface of the sensor. When no force is applied, the sensora??s electrodes are not in contact, and the resistance ROFF tends toward infinity. When a force is applied, the sensora??s electrodes are in contact, and the resistance RON tends toward 0. The minimal actuation force is as low as 0.01N.