Chai Station (IoT-Enabled Automated Tea Vending Machine)

Abstract

Automation is now a way of life in most areas of life, yet in the preparation of tea in ofces and universities in Pakistan, manual labour remains virtually undone. The outcome is poor quality, hygiene issues and a repetitive consumption of staff time. This thesis proposes the Chai Station, a smart tea vending machine with IoT capability that prepares traditional milk tea in Pakistan and dispenses customised cups to authenticated users using a mobile web-based interface, brewed out of raw liquid and solid tea ingredients. The entire system operates on a single ESP32 microcontroller which controls hardware actuation, reads digital temperature sensors, hosts a local web application and communicates with Google Firebase Realtime Database to authenticate users and manage balances.. The physical layout of the machine is as follows: an upper zone, containing the main boiler, which brews tea with a three-cycle boiling program under infrared induction heating, a middle zone, which contains the intermediate boiler, which holds the serving temperature with conventional induction heating, and a lower zone, which houses the sugar dispenser, limit switch, and dispensing solenoid, serving single cups. Students scan in on their phones with enrollment data, choose one of three levels of sugar, grab their cup, and pick up their chai. An admin panel with a password provides the operators with complete access to brewing, student accounts, pricing and live monitoring. The sequential operational logic with power recovery, which is non-volatile and stored, safeguards student balances during unforeseen power failure. Ten full brewing cycles of testing ensured the consistency of the quality of brews, the integrity of the Firebase integration, and the responsiveness of web interfaces on Android and iOS platforms.