Greenhouse Automation - Environment Manager
The Environment Manager consists of a Raspberry Pi
single-board computer (with standard USB 5 VDS power supply)
executing custom software and augmented with an external
RS485 communication driver and an external
humidity/temperature sensor. In the prototype installation the
Raspberry Pi inside of a commercial enclosure is mounted in
a corner of the greenhouse (see area picture below on the
left, close-up on the right). In the close-up picture, the
Raspberry Pi and external components are left of center and
12 VDC 10A power supply is right of center.
Environment Manager mounting
Environment Manager mounting, close-up
The custom software monitors the greenhouse temperature
(currently using the external sensor) and uses this data,
along with the time of day, to manage the temperature of the
greenhouse. It accomplishes this by sending commands to the
controllers using the Raspberry Pi serial port (routed
through the external RS485 communication driver) that open
or close the greenhouse vents, turn the circulating fan on
or off, or set the speed of the exhaust fans. This
functionality will be enhanced when the thermal controller
is deployed to provide more precise temperature readings and
control thermal storage water circulation.
The Raspberry Pi is a full-featured computer with monitor
output, keyboard and mouse support, audio output, USB device
and ethernet connectivity, and many other capabilities.
Currently the prototype system is 'headless'—any
changes to the system are effected through a network
connection. Future plans are to equip the Pi with a small
touch screen and speaker so that greenhouse management data
and settings can be viewed and adjusted.
Also, because the Raspberry Pi is surrounded by a large
world-wide community of users and employs a variation of the
Linux operating system, it offers a wide range of
programming languages and methods. Since the connection to
the controllers is through the serial port, any of these
languages or methods could potentially be used to create a
custom greenhouse management application. Or for that
matter, an entirely different computing platform could be
used, such as an Arduino, instead of the Raspberry Pi.