ZigBee-based climate measurement system for thermal comfort in traffic busses

Abstract: This thesis describes the work process two (WP2) of a project led by the traffic administration in Stockholm to achieve the passengers' thermal comfort in traffic buses.  The purpose of this thesis is to design and implement a measurement system comprised in eight measurement position in a bus. Each position is able to transmit data using a wireless communication protocol, with a central unit collecting all the transmitted data taking into consideration the accuracy of the measurements and filtering out the incorrect data. In order to accomplish this, a literature study is conducted investigating different measurement methods for different parameters, different communication protocols were analysed as well to determine an appropriate communication protocol suitable for climate measurement in a bus environment with passengers present on board.  The output of the HVAC system is also required to help the traffic administration demonstrate the results of adjusting the temperature in the bus to reach the thermal comfort and how it led to saving energy. The system incorporates ZigBee , ESP32 microcontroller in the sender positions and a Raspberry pi operating as a central unit to collect data and store it in a file system providing an accurate data that will help the traffic administration achieve their goals. Unfortunately, there were some diffculties accessing CAN system data to provide the output of the HVAC system.