We are working on a new type of project at Sprout, one that we hope will bring more students into the garden by engaging their interest in technology. We are building sensors to put in the garden that will measure the soil moisture level and send a signal to let us know when the garden needs to be watered. It will also track the soil moisture over time.
We’d like to expand this project to include other kinds of sensors, including temperature, humidity, activity in the garden, noise, and more. Suggestions welcome!
We’ll be building the sensors from several parts, and programming them. We’ll use open source hardware and software for the project so this will be entirely replicable in your own garden.
The idea to do this project came from learning about Arduino, which is a physical computing platform that includes two parts: a hardware component, the microcontroller board, and a software component, the program used to tell the hardware what to do.
The Arduino system was developed at a university in Italy to give students a less expensive way to build and test their own interactive design projects. There is a wonderful video about it here.
The software for Arduino is free and can be downloaded from their incredibly helpful and informative website here.
For our first setup we are using products from SeeedStudio. We’d like this to be a wireless set up, so we need a battery for power, and we’re using a small solar panel to keep the battery charged. We’re also using a WiFi component so it does not need to be connected to an ethernet cord, it can connect to a WiFi router and send out the information from the sensor. Here are the parts we purchased (each image is a link to the product page on the SeeedStudio website):
By far the most expensive part of this set up is the WiFi bee so if you can connect directly to the ethernet, that will make the project more affordable. We may try to connect several sensors to one WiFi bee to reduce the cost, but this will mean having wires running between them.
The benefit of this inaugural sensor is that it is built of components that easily snap together. As we grow more comfortable with the system, we will build more of the individual parts ourselves. One resource for building your own sensors is GardenBot.
The hardware for our first sensor has been assembled and fits in a small Tupperware container. The challenge now is connecting to the WiFi router at the school. The technology for the WiFi bee is not very advanced so it needs a static IP address to be assigned to it. For that we need tech support at the school. Our backup plan is to get our own WiFi router and connect it to the ethernet at the school and set it up ourselves. Again, suggestions welcome!
Once the sensor is up and running we will track our data using Cosm, a platform that connects to the device and provides real-time control (sending a message when the soil moisture reaches a set level) and data storage (a chart of the soil moisture level over time). We’re hoping to collect that information and have it readily available here on the Sprout Farms website for you to access at your leisure.
Check out Part 2 of this project here: http://sproutfarms.org/garden-sensor-part-2/
Thanks to Michael Zick Doherty of Bitponics for advice on how to get started and where to find parts!
Other resources for open source hardware: