Project Hub /Security Surveillance & Defense/Laser Fence Security/Arduino Based Liquid Vending Machine

Intermediate

ARDUINO

₹1,500 – ₹5,000

3 – 6 Hours

Partial Kit

Arduino Based Liquid Vending Machine

An automatic liquid vending machine controlled by RFID tags to dispense a fixed amount of liquid safely and efficiently without human intervention.

Originally published on ElectronicsForU

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

Arduino UNO R3 Board (Compatible) – ATmega328P Microcontroller with USB Cable Rs. 999.00
RFID Reader/Writer RC522 SPI S50 with RFID Card and Tag Rs. 190.00
5V 1 Channel Relay Module Rs. 87.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

We don't carry yet: LCD (generic / unspecified)
Water Flow Sensor
Solenoid / Electric Lock

Browse all components

How It Works

The Arduino Based Liquid Vending Machine is an automated dispensing system managed by an Arduino Uno microcontroller. The core operation begins when a user presents an RFID tag to the EM-18 RFID Reader. The reader scans the tag's unique identification data and passes it to the Arduino Uno for verification. Once the ID is recognized, the system initiates the dispensing cycle. The Arduino signals a single-channel relay to switch on, which in turn activates the 12V Solenoid Valve to open the fluid line. As the liquid flows through the system, an analogue water flow sensor continuously monitors the volume and sends pulse signals back to the Arduino. Throughout this process, a 16x2 LCD Display provides real-time visual feedback to the user, showing status messages and dispensing progress. When the flow sensor measures that the target liquid volume has been reached, the Arduino immediately turns off the relay, closing the solenoid valve and safely stopping the flow. The entire setup is powered by a stable 12V DC power supply, ensuring reliable operation of both the logic components and the electromechanical valve.

Why Build This

Develop practical technical skills by integrating RFID identification systems with electromechanical control valves suitable for industrial and diploma-level automation projects.

Implement automated fluid measurement and inventory control solutions applicable in hospitals, schools, and public water distribution setups.

Gain hands-on experience in combining microcontrollers with sensors, actuators, and displays to create a complete, standalone commercial prototype.

Real-World Application

Can be utilized in hospitals for automated milk dispensing, educational institutions for 24/7 beverage access, events for juice dispensing, or in rural areas for reliable water distribution.

Skills You'll Learn

RFID data reading and parsing

relay control of electromechanical actuators

analogue pulse counting for flow measurement

LCD screen interfacing

power management for mixed-voltage systems

Safety Precautions

Ensure proper isolation when working with 12V DC power supplies and liquid components to prevent electrical shorts.

Technology Tags

ARDUINO

RFID

EM-18

SOLENOID VALVE

FLOW SENSOR

LCD DISPLAY

RELAY

HALL EFFECT

Frequently Asked Questions

Can any RFID tag be used to dispense liquid?

No, the system requires specific RFID tags whose unique IDs are pre-programmed and authorized in the Arduino code to trigger the dispensing mechanism.

How does the Arduino know when to stop the liquid flow?

The analogue water flow sensor tracks the volume passing through the pipe in real-time, and once the target amount is met, the Arduino shuts off the relay.

Why is a relay used instead of connecting the solenoid valve directly to the Arduino?

The 12V solenoid valve requires more voltage and current than the Arduino Uno digital pins can safely provide, so the single-channel relay acts as an electrically isolated switch.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

PRJ-00201