Comparative Analysis and Calibration of Low Cost Resistive and Capacitive Soil Moisture Sensor

TL;DR

This paper compares low-cost resistive and capacitive soil moisture sensors through calibration and response analysis to guide their effective use in smart irrigation systems.

Contribution

It provides a detailed comparison and calibration of resistive and capacitive sensors, highlighting their suitability for soil moisture monitoring.

Findings

Resistive and capacitive sensors show different calibration curves.

Sensor responses vary with water addition, affecting accuracy.

The analysis aids in selecting cost-effective sensors for agriculture.

Abstract

Soil moisture is an essential parameter in agriculture. It determines several environmental and agricultural activities such as climate change, drought prediction, irrigation, etc. Smart irrigation management requires continuous soil moisture monitoring to reduce unnecessary water usage. In recent times, the use of low-cost sensors is becoming popular among farmers for soil moisture monitoring. In this paper, a comparison of low-cost resistive and capacitive soil moisture sensors is demonstrated in two ways. One way is the calibration of the sensors in gravimetric and volumetric water content, and the other is the sensors' response analysis when different quantities of water are added to the same amount of soil. The analysis shown in this work is essential before choosing cost-effective sensors for any soil moisture monitoring platform.