Design And Implementation of Smart Vending Machine

Abstract

An RFID configured vending machine is a smart automated system that uses Radio Frequency Identification (RFID) 
technology to enable cashless and secure transactions. Unlike conventional vending machines that rely on coins or 
paper currency, this system identifies users through an RFID card or tag containing a unique identification number. 
When the RFID card is placed near the RFID reader, radio frequency signals are used to wirelessly read the stored 
information. 
The retrieved data is transmitted to a microcontroller or processing unit, which verifies the user's identity and checks 
the available balance stored in the system database. If sufficient balance is available, the machine allows the user to 
select a product using push buttons or a keypad. Once the selection is confirmed, the controller activates the dispensing 
mechanism, typically operated by a servo motor, to deliver the selected item. After successful dispensing, the system 
automatically deducts the corresponding amount from the user's balance and updates the database. The entire 
transaction is completed quickly and efficiently without the need for manual cash handling. 
RFID-configured vending machines improve security, reduce transaction time, minimize maintenance issues 
associated with cash handling, and provide better inventory management. Owing to these advantages, they are widely 
used in educational institutions, offices, hospitals, and other public places where fast, secure, and reliable service is 
essential. This work presents the implementation of a Radio Frequency Identification (RFID)-based multiproduct 
vending machine designed to automatically dispense beverages such as coke, malt, and yogurt using an RFID prepaid 
payment system. After carefully analyzing the limitations of the existing vending system, a new design was developed 
to overcome its shortcomings. 
The proposed system was implemented using an Arduino Mega microcontroller, an RFID reader and RFID cards, a 
servo motor, a Liquid Crystal Display (LCD), and other supporting electronic components. A prototyping methodology 
was adopted, where both hardware and software modules were designed, tested individually, and then integrated to 
form the complete system. The embedded software was developed using the C programming language to coordinate 
the operation of all hardware components effectively. Customers can purchase products by swiping their RFID cards 
across the RFID reader, after which the embedded system authenticates the card, deducts the product cost from the 
stored balance, dispenses the selected product, and displays the remaining balance on the LCD. The developed system 
provides a secure, efficient, and user-friendly cashless vending solution suitable for modern automated retail 
applications.