Additively Manufactured Electromagnetic based Planar Pressure Sensor using Substrate Integrated Waveguide Technology

Abstract This paper proposes an electromagnetic based planar pressure sensor using a substrate integrated waveguide (SIW). The proposed pressure sensor is inspired by a rectangular SIW cavity and is additively manufactured using 3D printed dielectric material with inkjet printed conductive pattern. Since the resonance frequency depends on the SIW centre in transverse electrical mode, a circular cylinder with four bridges is placed at the SIW centre for perturbation. We inserted meshed material at the SIW centre, to facilitate soft pressing, and simplify producing frequency shifts due to capacitive coupling perturbation from different pressure levels. The proposed concept was numerically and experimentally verified, reducing resonance frequency from 4.28 to 3.71 GHz by increasing the pressure from 0 to 2.4 kPa. Device sensitivity = 2.4 × 108 Hz/kPa, and stable frequency change was observed over 100 repeats.