A mobile sensor package for real-time greenhouse monitoring using
open-source hardware
Abstract
Increased demand for precision agriculture is reflected by a global rise
in greenhouse food production. To maximize crop efficiency and yield,
commercial greenhouses require live monitoring of growth conditions.
Recent advances in open-source hardware allow for environmental sensing
with the potential to rival lab-grade equipment at a fraction of the
cost. This study introduces a high-resolution sensor package that costs
less than $400. Consisting of microcontrollers and small open-source
hardware, the sensor package can be deployed on the HyperRail, a modular
conveyance system developed in Oregon State University’s OPEnS Lab. The
system can then provide data from multiple sensing locations at the cost
of a single package. Sensor data, including CO2, temperature, relative
humidity, luminosity and dust/pollen, is saved to a microSD card as the
HyperRail-mounted package travels throughout the greenhouse. A wireless
GFSK nRF connection to a network hub allows the broadcast of a live
stream of environmental conditions online. CO2 monitoring efforts are
especially relevant to greenhouse management as artificially elevated
levels can significantly increase plant growth. Results from calibration
in the lab show that the K30 CO2 sensor ($85) can be calibrated to be
accurate within less than 10 ppm of industry standard equipment costing
up to $10,000. Our sensor package’s instructions, code, wiring, and
3D-printed enclosures are openly-published on GitHub. Addition of an
RFID tag soil moisture sensing system is anticipated. Actuators may also
be integrated in the future, allowing the system to automatically adjust
greenhouse controls (i.e. CO2, water) in response to sensor readings.
The affordability of this package can make precision agriculture more
accessible in developing countries where conventional monitoring systems
are not feasible. Efficient use of resources and the ability to adapt to
local challenges with input from the open-source community has the
potential to improve global crop yield.