Eddy current pressure sensor based on planar coil

Abstract

The traditional pressure sensors are mostly based on piezoresistive, piezoelectric effect, and strain gauge, which are easily affected by ambient temperature. The structure of some sensors is rather complex to effectively acquire the signal or measure distribution force. Therefore, a pressure sensor based on the planar coil and elastic element was designed to solve this problem. The newly designed sensor has a spiral planar coil made by a printed circuit board and a polydimethylsiloxane (PDMS) thin film as the elastic element. The conductive layer is attached on the upper surface of PDMS to realise the eddy current effect. Meanwhile, a simulation model was established to find the relationship between deformation displacement and the pressure of the elastic element. By generating the experimental curves of the deformation displacement of the elastic element and the output frequency of the eddy current sensor, the pressure measurement on the surface of the elastic element can be identified. The preliminary experimental results showed that the eddy current pressure sensor based on the plane coil has good linearity and repeatability, and it can realise large area distributed pressure measurement, which is also suitable for accurate measurement of distribution force.

Keywords

• pressure sensors
• printed circuits
• coils
• strain gauges
• pressure measurement
• electric sensing devices
• eddy currents
• piezoresistive effect
• piezoelectric effect
• elastic element
• newly designed sensor
• spiral planar coil
• eddy current effect
• deformation displacement
• eddy current sensor
• pressure measurement
• eddy current pressure sensor
• plane coil
• traditional pressure sensors