In a previous post (http://l-k.me/J) I described an idea I had to make use of a Raspberry Pi as a local sensor tool on a bee hive, a project I’ve dubbed ‘BeePi’.
Below is a small requirement chart for the projects needs and potential:
| Requirement | Must Have | Would Like To Have | Nice To Have |
| Internal Hive Temp Sensor | Yes | ||
| External Hive Temp Sensor | Yes | ||
| XYZ Accelerometer | Yes | ||
| High Capacity Battery | Yes | ||
| Solar Charging Battery Charger | Yes | ||
| WiFi Transmitter | Yes | ||
| WiFi Hub | Yes | ||
| 3G Connectivity | Yes | ||
| Hive Disassembly Sensor | Yes | ||
| RFID Antenna | Yes | ||
| Weather Station | Yes |
While all of these could be rolled into a singular project, but it makes sense to break up development into phases based on real world requirements and (of course) money.
A lot of what is required for this project exists in singular projects already published by the Raspberry Pi community, a large following of users are making use of the Maplin USB Weather Station (http://l-k.me/I), GPIO Temperature Sensor(s) (http://l-k.me/K) and RFiD Reader (http://l-k.me/L). The use of a 3G and / or WiFi dongle makes sending data exceptionally easy as the OS will handle any of the connecting to the internet / network leaving any software to make / receive API calls and store the data where appropriate.
The use of the BeePi as a WiFi Hub is also worth considering if you have more than one hive in a location it makes sense to have a singular hub / data collecting server that all of the other BeePi’s connect to. There are many tutorials on the internet that show you how to turn your Raspberry Pi into a WiFi hub and make use of a singular 3G dongle to connect them all to the internet (Or even host the database locally).
After a bit of juggling and budgeting my Phase One build will look like this:
| Internal Hive Temp Sensor |
| External Hive Temp Sensor |
| XYZ Accelerometer |
| High Capacity Battery |
| Solar Charging Battery Charger |
| USB WiFi Transmitter |
I don’t want to host the data from the hive locally (on the BeePi), so I will write a program to gather up the sensor data periodically and then send the data to a database hosted somewhere (more to come on that as it is developed).
I want to capture the internal brood temperature, external atmospheric temperature, XYZ geometry of the hive. The BeePi will be powered by a chunky long life battery which will be maintained by a solar panel. The hive will be connected to my WiFi network via USB WiFi stick.
To aide development and keep phases in line with each other I will design any PCB’s to include the optional bits; RFiD reader, Hive Disassembly Sensor, 3G data stick. So that should I need to add these to my project or as requirements change I don’t have to go back to square one and make a new base-board.
For the sensors I am going to be using; I’ve chosen to keep things simple:
Internal and External Temperature Sensor: DS18B20 3 Pin 1 wire temperature, these are particularly handy and cool as you can connect several to the same GPIO pin but capture data from them all separately via serial interface. The tutorial guide I am using is: (http://l-k.me/K).
XYZ Accelerometer: ADXL345 a simple I2C accelerometer which you connect via the BeePi’s GPIO Pins (http://l-k.me/M).
Power and Solar: Power will come from a 12V 7AmpHour battery which will be charged via solar panel regulated with a solar charge controller. The board I will design will take 12V and step down to 5V which will be used to power the Raspberry Pi, WiFi and connected devices. The hope is that the battery and sun will maintain the project indefinitely however as this is all theoretical (at time of writing!) I may need A) a bigger battery B) a bigger solar panel C) BOTH.
While you can source all of these components from UK distributors, I HIGHLY recommend looking at eBay and sellers who are based on HK or china as I have found the price difference to be considerable between UK and Asian sellers.
More to come as the project develops!