Flexible Piezoresistive Flow Sensor Based on PDMS and Graphite Particles

Combining conductive fillers such as graphite with an elastomer such as polydimethylsiloxane (PDMS) allows the development of flexible sensors. The flexible sensors provide properties that are difficult to achieve with conventional sensors. In this paper, there is an attempt to design a flow sensor based on piezoresistive nanocomposites. A piezoresistive layer is fabricated with PDMS and graphite as fillers with the spin coating process. The fabricated piezoresistive layer is used to obtain a U-cantilever shape and then assembled with other 3D printed parts to obtain the final sensor. Before this, mechanical characterisation is performed to obtain the gauge factor and Young modulus of the PDMS composite material. Then, the flow sensor device is tested by measuring the resistance change under different fluid velocities.