Smart Ration Vending Machine 🌾

An automated, IoT-based public ration dispensing system built on a Raspberry Pi Zero 2 W. Beneficiaries authenticate with an RFID card or fingerprint, and the machine automatically dispenses their exact monthly wheat and rice quota by weight — no manual measuring, no ledger, no queue at a counter. Every dispense is logged to Firebase in real time and confirmed to the beneficiary by SMS.

This was built as a working prototype (housed in a cardboard enclosure) to validate the full electronics + software pipeline before a production enclosure.

🔗 Live demo: smart-vending-machine-f1d77.web.app (admin: admin / admin1234 — demo credentials, see security note below)

Why

India's Public Distribution System (PDS) still relies heavily on manual verification and hand-measured quotas at ration shops, which is slow and vulnerable to short-weighing and identity fraud. This project explores a low-cost, unattended dispensing kiosk that verifies identity two ways (RFID + fingerprint), weighs each dispense with load cells for accuracy, and gives both the beneficiary (via SMS) and the administrator (via a live dashboard) a transparent, timestamped record.

Features

• Dual-factor authentication — RFID card scan or manual ration card number entry (4x4 keypad), followed by fingerprint verification
• Weight-accurate dispensing — two servo-controlled hoppers (wheat + rice), each monitored by an independent HX711 + load cell so dispensing stops the instant the correct quota (in grams) is reached
• Real-time database — every user record, quota, and dispense timestamp is synced to Firebase Realtime Database
• SMS confirmation — GSM module (SIM800L) texts the beneficiary the moment their ration is dispensed, with the exact date and time
• Live LCD feedback — 16x2 I2C display walks the user through each step (scan → verify → dispensing → done)
• Web admin panel — add/update/delete beneficiaries, search by RFID/name/ration ID/mobile, reset quotas, and view last-dispense history, all synced live via Firebase
• Safe power on/off — physical push button for a clean shutdown sequence

How It Works

1. LCD shows "Smart Vending Machine" for 2 seconds, then prompts continuously: scan RFID or enter ration card number
2. User either scans their RFID tag or types their ration card number on the keypad (entry echoed live on the LCD)
3. Once the ID matches a record in Firebase, the system moves to fingerprint verification against the R307S sensor's onboard memory
4. On success:
   • Servo 1 rotates from its resting position (90°) to 45°, releasing wheat from the hopper onto load cell 1
   • Dispensing stops automatically once the measured weight matches the user's stored wheat_quota, and the servo returns to 90°
   • Servo 2 then rotates from 130° to 70° to dispense rice, stopping at the stored rice_quota before returning to rest
5. The Pi fetches the real-time clock, sends an SMS via the GSM module, and writes the dispense timestamp back to Firebase

SMS format:

Dear <mobile number> your Ration for the month <MONTH NAME>,<YEAR> has been collected at <HH:MM:SS>

Thank You !

System Architecture

Block diagram — input modules, processing unit, authentication flow, automatic dispensing flow, and output modules:

Software flowchart — full control loop from boot to dispense:

Results

The admin panel is deployed on Firebase Hosting and tested end-to-end against the live Realtime Database — adding, editing, and resetting users all update the table instantly.

SMS confirmation received on dispense, matching the format defined for the project:

🎥 A full demo video of the hardware + dashboard working together is at demo/demo-video.mp4.

Firebase Realtime Database Schema

users/
  <RFID_TAG_ID>/
    ration_card_id
    fingerprint_id
    name
    mobile
    wheat_quota
    rice_quota
    last_dispense_time

Hardware

Component	Purpose
Raspberry Pi Zero 2 W	Main controller
R307S fingerprint sensor	Second-factor biometric verification
EM-18 RFID reader	Card-based identification
4x4 matrix keypad	Manual ration card entry
16x2 LCD (I2C)	User-facing status display
2x load cell + HX711	Precision weight measurement (wheat, rice)
2x servo motor	Hopper gate control
SIM800L GSM module	SMS notifications
DS1307 RTC	Accurate timestamps
Push button	Safe power on/off

Full wiring reference: docs/pin-connections.md

Admin Panel

A browser-based dashboard for managing beneficiaries, built with vanilla HTML/JS and the Firebase SDK — no backend server required.

• Add, update, reset-quota, and delete users, with duplicate checks on RFID/ration ID/mobile/fingerprint
• Live search across all fields
• Paginated user table with last-dispense timestamps
• Session-based login gate

⚠️ Known limitation: the admin login (admin-panel/login.html) currently checks a hardcoded username/password directly in client-side JavaScript, which means the credentials are visible to anyone who views the page source. This is fine for a local prototype demo but should not be used as-is for a public deployment — a production version should authenticate against Firebase Auth or a backend, not a hardcoded client-side check.

Project Structure

cloud-based-smart-ration-vending-machine/
├── raspberry-pi/
│   ├── main.py            # Main control loop (sensors, dispensing, Firebase, SMS)
│   └── requirements.txt
├── admin-panel/
│   ├── index.html          # Dashboard (user management)
│   └── login.html          # Admin login gate
├── docs/
│   ├── pin-connections.md  # Full GPIO wiring reference
│   └── diagrams/           # Block diagram + software flowchart
├── images/                 # Build photos
│   └── screenshots/        # Admin panel + SMS screenshots
├── demo/
│   └── demo-video.mp4      # Hardware + dashboard demo
└── README.md

Setup

Raspberry Pi

git clone https://github.com/<your-username>/cloud-based-smart-ration-vending-machine.git
cd cloud-based-smart-ration-vending-machine/raspberry-pi
pip install -r requirements.txt

1. Enable I2C and UART, and disable the serial console, via raspi-config
2. Wire all components per docs/pin-connections.md
3. Add your own Firebase service account key at serviceAccountKey.json (not included — see below) and update the databaseURL in main.py
4. Run:

   python3 main.py

Admin Panel

Open admin-panel/login.html in a browser, or host the admin-panel/ folder on any static site host. Update the firebaseConfig object in index.html to point at your own Firebase project.

Firebase Credentials

This repo does not include a serviceAccountKey.json or any real device credentials — you'll need to generate your own from the Firebase console (Project Settings → Service Accounts) and keep it out of version control (already covered by .gitignore).

Roadmap / Future Improvements

• Replace hardcoded admin login with Firebase Authentication
• Move Firebase config out of client-side source into environment-based config
• 3D-printed or laser-cut enclosure to replace the cardboard prototype
• Offline queue for SMS/DB sync during network outages

License

MIT — see LICENSE