Extend Your Feelers

The winters in Germany's Sauerland region are long, but above all, changeable. Sometimes it snows in October, and sometimes you experience a spring-like 15°C (59°F) over Christmas. The beekeepers in the area are prepared for this and prepare their bees for the winter in the early autumn after the last honey harvest by feeding several liters of sugar solution into the hives, depending on the size of the bee colony. When the outside temperatures drop, the response is prompt: Lock up, install mouse gratings in front of the entrance, and meet again in April.

Because beekeepers do not normally open the hives during the winter months, they cannot know if the population is thriving. Inspired by the Hiveeyes Project [1] and the Open Hive Monitoring System [2], we planned our own monitoring solution for our colonies. As hobby beekeepers, we first want to observe the temperature (see the "Test Setup" box) but, later, also connect our own hive scale.

Connecting the DHT11 Sensor

The DHT11 digital temperature and humidity sensor is available for a few dollars. It supplies the temperature in degrees Celsius and the relative humidity as a percentage. In the first trial, we connected the sensor directly to the RPi2B. The Python_DHT sensor library [3] helps with the readout. After installing the packages build-essential and python3-dev, we checked out the sensor library from the GitHub repository and installed it on the computer:

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