Introduction: Modernizing Attendance with IoT
This system transforms attendance tracking from a manual task into an automated real-time process, making it ideal for schools, enterprises, and events.
Key System Capabilities
- Automated & Contactless Logging: RFID-based attendance with no manual input.
- Real-Time Cloud Sync: Secure Google Sheets integration with
HTTPSRedirect. - Affordable Build: Hardware cost under $20 using commodity components.
- Easy Wi-Fi Setup: WiFiManager captive portal for quick configuration.
- Secure Data: HTTPS encrypted communication ensures reliability and safety.
System Architecture & Workflow
The NodeMCU functions as the core processor, managing hardware interactions and secure cloud communication. Below is the complete workflow:
| Step | Action | Technology | Output |
|---|---|---|---|
| 1 | Card Scanning | RFID RC522 | Unique UID captured |
| 2 | Processing & Feedback | NodeMCU + LCD/Buzzer | Timestamp generated, status displayed |
| 3 | Cloud Communication | ESP8266 + HTTPSRedirect | Data sent securely to Google Apps Script |
| 4 | Data Validation | Apps Script | Checks duplicates, validates payload |
| 5 | Database Lookup | Google Sheets (Database) | Enriches UID with user details |
| 6 | Attendance Logging | Google Sheets (Attendance) | Record appended |
| 7 | Response | Apps Script | Success/failure sent back |
Hardware Implementation
Components Required
| Component | Function | Qty |
|---|---|---|
| NodeMCU ESP8266 | Microcontroller & Wi-Fi core | 1 |
| RFID RC522 | Card/tag reader | 1 |
| LCD 16x2 (I2C) | Status display | 1 |
| Buzzer & LED | Feedback indicators | 1 each |
| Push Button | Wi-Fi reset trigger | 1 |
| RFID Cards/Tags | User credentials | As needed |
Deployment Note:
The RC522 RST pin is handled via software reset. GPIO0 push button uses the internal pull-up resistor.
Software Implementation
NodeMCU Firmware (Edu_Track_Pro_Code.ino)
Handles hardware initialization, Wi-Fi, and secure POST requests.
- WiFiManager
- MFRC522
- LiquidCrystal_I2C
- HTTPSRedirect
Google Apps Script (Edu_Track_Pro_App_Script.txt)
Acts as a secure serverless backend.
- Receives POST data via
doPost() - Checks/creates Database & Attendance sheets
- Links UID with user details
- Maintains Nepal Time consistency
Conclusion & Future Development
EduTrack Pro is a professional-grade IoT attendance system, combining affordable hardware with reliable cloud services. Its flexibility allows applications beyond classrooms, such as corporate offices and labs.
Future Enhancements
- Integrating NTP for precise time sync
- OLED upgrade for richer display
- MQTT support for bi-directional communication
- Local duplication prevention
- Battery/UPS integration
