One of the main reasons that I started analog.io was because I had an interest in using internet connected sensors to measure various sensors inside of bee hives. The first thing that I wanted to do was measure the Temperature and Humidity of a set of Bee Hives in Wisconsin over the winter.
There are quite a few challenges associated with this:
So for the first iteration, it was clear that I needed to create my own wireless temp & humidity sensor and it also needed to get at least 260ft+ of range. It also needed to survive the attenuation of the hive and house and be low enough power to survive the winter without charging or power. Here's what I came up with:
(ignore the imp.guru logo, this was the name of the web application prior to me acquiring analog.io)
So these were the sensors, I then needed something to connect these to the internet. For this I created a 915MHz radio to WiFi bridge which I simply call "The Hub". It has a LNA/PA front end, then uses an Electric Imp to bridge the packets over to WiFi. From there, I wrote some Electric Imp Agent code to upload the data to analog.io.
With all of the hardware setup, I did some range tests and found that I could get great range with the radios (about 300ft) but unfortunately as soon as they were installed into the hives, the attenuation was pretty bad, reducing my range to only 100 ft. With winter closing in, I did this installation:
So I'm happy to say that this setup worked almost continuously for 5 month, and captured some pretty cool data:
It is amazing to think that the temperature inside of a bee hive can be 77 deg F while the outdoor temp is negative 6! It is also amazing to me that all of my hub hardware survived the bitter cold and is still running today.