Open source weatherstation developed in IoT style. Publishes data to PlotLy and local web server.

The station is based on Rasberry Pi Zero platform, which means that almost any digital sensor can be easily integrated into the platform. With additional ADC modules, analog sensors could also be included.

The current version has two temperature probes (more can be easily added). The probes are based on DS18b20 digital sensor and should be accurate within 0.5C in -10C to 85C range.

Humidity is measured insie the case and utilises DHT11 digital temperature sensor. This sensor is accurate to 5% with in 20%-80% range.

The pressure is measured with BMP180 which is capable of sensing pressure changes as low as 0.02 hPa, which means that altitude changes of 0.17m could be detected. The pressure sensor is also placed inside the case.

The weatherstation should be paired with a corresponding mini wifi router so that it automatically connects to it. Once connected, it will automatically pull the latest code version from this GitHub repository and start publishing data to its own webserver and to plotly.

The data can be viewed at https://plot.ly/dashboard/BeckyWeather:10/view by anyone. The internal web server can be accessed from the mini routers wifi network and can be seen at http://192.168.8.100

The main script of the program is fairly rudimentary and more of a proof of concept, but it does offer few options for configuring the data. The most important value affecting the usage is the

resolution_secs = 5

Parameter which determines how often the data is captured. This affects how much history is retained as plotly supports roughly 10 000 data points and the internal web server holds roughly 10 times more. Increasing this delay will make the data more sparse and enables the user to see much further into the history but hides weather events that happen quickly.

The actual construction of this particular project was done on a strip board but any type of prototype board will do. Solderless breadboards are recommended for the prototyping phase.

The schematic of the project can be found below: