Automation

Electrical engineering

Aerospace engineering

Hydraulics

Nanotechnology

Process engineering

Characterization (materials science)

Engineering

Moisture

Embedded system

Soil science

Composite material

Geotechnical engineering

Materials science

Capacitive sensing

Water content

Soil moisture sensor

Computer science

Environmental science

Mechanical engineering

Internet of Things

Sensors

The rapid development and wide application of the IoT (Internet of Things) has pushed toward the improvement of current practices in greenhouse technology and agriculture in general, through automation and informatization. The experimental and accurate determination of soil moisture is a matter of great importance in different scientific fields, such as agronomy, soil physics, geology, hydraulics, and soil mechanics. This paper focuses on the experimental characterization of a commercial low-cost "capacitive" coplanar soil moisture sensor that can be housed in distributed nodes for IoT applications. It is shown that at least for a well-defined type of soil with a constant solid matter to volume ratio, this type of capacitive sensor yields a reliable relationship between output voltage and gravimetric water content.

Characterization of Low-Cost Capacitive Soil Moisture Sensors for IoT Networks