Electronics
At the centre of the remote data capture hub is a NodeMCU microcontroller unit. The NodeMCU is an opensource IoT development board that comes in a bewildering range of variations. The Hivescientia system uses a 38 Pin ESP32 WROOM-32 from AZDelivery. This provides a great range of GPIO pins for SPI/i2C communications and analogue/digital inputs and outputs.
Sensors
In order to provide a full range of data there are a number of different sensors in use. An important factor in selection beyond the data they sense has been the method of communication and reliability. You can read a past blog post on Sensor issues here.
The default arrangement for an hive set-up is:
| SENSOR | DESCRIPTION | EXTERNAL | TOP | BOTTOM | PORTABLE 1 | PORTABLE 2 |
|---|---|---|---|---|---|---|
| BME280 | Temp, Humidity, Pressure | Y | Y | Y | ||
| MAX31856 | Thermocouple | Y | Y | |||
| LTR390 | UV Sensor | Y | ||||
| AS7341 | Light Spectrum Sensor | Y | ||||
| Gas | ||||||
| Weight |
AS7341 – 10-Channel Light / Colour Sensor
Power and Memory
We use a Adafruit BQ24074 Universal USB / DC / Solar Lithium Ion/Polymer charger to get juice into the ‘High Capacity 13400mAh Lithium Ion Battery Pack’ battery with 3.7 nominal voltage from the 6V 3.5W Solar panel which outputs 6V at 530 mA via 3.5mm x 1.1mm DC jack connector.