Internet of Tomatoes
How did it start?
Internet of Tomatoes is my toy project. Its goal was to monitor my plants during my vacations, but with time it was extended to provide permanent monitoring of their health.
PS: In case you didn't notice it, this name is a very bad pun with the buzzword that shares the same acronym, Internet of Things.
Fig.1 Setup as of August 10th, 2017
The picture above shows the actual system from a viewpoint that the regular camera is not able to capture. Looking at it, it is possible to see the water reservatory with capacity of 10 liters completely full with a mixture of water and a crystal fertilizer. It's also possible to see the cardbox where the whole system is installed. The idea of a plastic container inside a cardbox was to provide water insulation in case of rain (which is rare in this region of California) and (limited) heat insulation from direct sunlight. On top of the cardbox, there are a bunch of cables -- the ones used to power the water pumps and that are gated through the relays. Fig.2 show where they are.
Fig.2 Pump installed inside a container of 1 gallon of water
Once turned on, the pump, which is connected to a pot via silicone tubing, will pump water directly to the plant substrate (Fig.3). I was familiar with these pumps and tubes as I previously had an aquarium system (somewhat automated), where they are extensively used.
Fig.3 Silicone tubing used to deliver water
Thanks to the awesome Raspberry Pi ecosystem, a lot of stuff that in past projects was a pain for me to setup, such as GPIO connections, was pretty straightforward. The overall system features a RPi3 at its core, connected to a 8-channel relay auxiliary board that controls 5 water pumps. Also connected to the RPi mainboard is a temperature/humidity sensor (Figs.4 and 5).
Fig.4 Inside the box
Fig.6 The end result
Here is a link showing a demo of the interface of the page served by the web server running in the raspberry pi. The idea is to show the status so the user can take a quick look at what's happening and access timelapses produced with pictures taken by the camera.