Meteorological station system

This bachelor thesis deals with the design and implementation of a online meteorological station system, which consists of individual weather stations that communicate via the Internet with the server. The first part of the thesis discusses the principles of measuring major meteorological variables and deals with the selection of suitable sensors for measuring temperature, atmospheric pressure, humidity, wind speed and rainfall. In the practical part, one of the weather stations based on Raspberry Pi Zero microcomputer is designed and realized. As a complement to the measured data, the station includes a camera that captures the view from the site where the meteostation is installed. 3D printing is used to realize most of the mechanical parts, it has the advantage of speed, accuracy and easy reproducibility. For the measurement of temperature, pressure and humidity, a combined sensor BME280 from Bosch is used, which is placed in a small Stevenson screen. The wind speed is measured by a cup anemometer whose rotation is sensed by an integrated Hall sensor. The output pulses are then counted using the PCF8583 circuit, which has an I2C interface for reading the values with a Raspberry Pi microcomputer. Special attention is paid to the construction of a custom calibratable tipping bucket rain gauge with a resolution of 0,5 mm, whose mechanical motion is also sensed by a Hall sensor as in the anemometer. The reading of the data from sensors and sending it to the server is handled by a Python script. For storing and presenting data to users, a custom server solution based on LAMP webserver is implemented, its source codes are written in PHP, HTML, JavaScript and CSS. In addition to the web interface, which displays the data in graphs, the measured data can be also presented to the user via an application for mobile devices based on Android. The application was developed in C# using the Xamarin framework in the Microsoft Visual Studio development environment. Among other things, it implements a widget for quick access to the measured values directly from the home screen. In the final part of the thesis, interesting findings obtained by observing the measured values are mentioned