Development of a Flexible Force Sensor using Additive Print Manufacturing Process

This paper reports on the development of a flexible polydimethylsiloxane (PDMS) based capacitive force sensor. The force sensor was fabricated by depositing silver (Ag) ink, as electrodes, on a flexible polyethylene terephthalate (PET) using additive screen-printing process. A dielectric layer was fabricated using PDMS which was prepared by mixing pre-polymer and a curing agent in a 16:1 ratio. The printed Ag electrodes were attached on either side of the PDMS. The capability of the force sensor was demonstrated by investigating its capacitive response towards varying applied forces. It was observed that the capacitance increased from 5.51 pF to 5.90 pF as the force was increased from 0 N (no load) to 10 N. A sensitivity and correlation coefficient of 0.13%N -1 and 0.9958 was calculated for the force sensor.