Capacitive fringing sensor based on PCB for the detection of moisture content in grain

Abstract

Grain moisture content is crucial for food processing and storage. A long standing issue with the food grains storage is moisture. In this paper an indirect method is introduced to measure moisture content in kabuli chana type chickpea grains. A spiral structured based capacitive fringing sensor is proposed to detect the moisture content in grains. Spiral structure based capacitive fringing sensor has been designed simulated on Ansys Maxwell 3- D and it was fabricated to measure moisture content of chickpea grains. The experiment was conducted on kabuli chana type chickpea grains with moisture content of 10% to 30% at about 25°C under laboratory conditions. The variation in the sensor capacitance value from 10 - 100 KHz frequency is demonstrating a linear relationship with the variation in moisture and weight of grains. The calibration equation was developed based on the experimental data. The results were also matched with the readings taken through commercially available digital agro moisture meter which indicate a linear relation between sensor capacitance and moisture content. The findings demonstrate that the capacitive sensor may be utilized to assess moisture in kabuli chana type chickpea grains.