This scale is now monitoring a hive at Wallington.
Automatic monitoring of the hive provides valuable information about what is going on under the lid. For many years the NASA Scale Hive project has been run using manual platform scales with daily measurements. In addition to information about the bees, this has revealed that over 15 years, nectar flows have moved earlier by about a week. Evidence of global warming! And serendipity in science.
More recently, the technology to install computers into hives has become cheaper and smaller. These have utilised a variety of computers and various recording or communications strategies. A small number of commercial systems have been marketed including Arnia (GPRS communications http://www.arnia.co.uk/) and Hivemind (satellite communications http://hivemind.co.nz/).
Solar powered computer monitoring
For my project, I’ve chosen the Sodaq version of the Arduino microprocessor. Sodaq offers a unique conjunction of solar power, microprocessor board and GPRS (mobile phone network) communication, making it the outstanding technology available for beehive monitoring (especially since apiaries are often relatively remote and without power). Hive weight, temperature and humidity are monitored, and later entrance traffic will be added.
The Sodaq team (with whom I have no commercial relationship) continue to develop their products rapidly. The Mbili was a huge advance and much easier to program than the Moja due to having separate ports for the serial monitor and GPRS. More recently they have crowd-funded a new model. the Autonomo which will be more powerful still.
Sensors for temperature, humidity and pressure are readily available off the shelf. I have had a temperature/humidity sensor installed just under the inner hive lid and also a one-wire thermometer that threads down into the brood chamber. However, these are not currently in place . It is quite tricky to get the probe into the center of the brood nest, although when correctly positioned it reads a steady 35 Celsius.
GPRSbee + Antenna + SIM card
LiPo Battery 1200mAh
Solar Panel 1.5W
TPH Sensor Board (Temperature Pressure Humidity) SHT21 BMP180
OneWire Temperature Sensor DS1820
Temperature/Humidity Sensor DHT11
Sparkfun Load Cell Amplifier HX711
Load Cell Sensor 0-40kg (x4)