SmartTrack RFID Attendance System
An IoT-based attendance tracking system built with an ESP32 microcontroller, an MFRC522 RFID reader, and an OLED display. It captures unique card IDs and transmits them to a remote server via HTTP for logging and processing. The system provides real-time user feedback through a local display and manages Wi-Fi connectivity for seamless data synchronization.
Automating attendance tracking is a common challenge in educational and corporate environments. SmartTrack offers a streamlined solution by leveraging the ESP32’s Wi-Fi capabilities and RFID technology to create a connected logging system that eliminates manual paperwork.
System Overview
The system is built around the ESP32 microcontroller, chosen for its integrated Wi-Fi and robust processing power. It serves as the central hub, interfacing with two main peripherals to handle user interaction and data acquisition. The hardware stack includes an MFRC522 RFID reader for scanning tags and an SSD1306 OLED display to provide immediate visual feedback to the user.
Functional Workflow
When a user brings their RFID tag near the reader, the ESP32 extracts the unique identifier (UID) from the chip using SPI communication. Once the ID is captured, the system performs the following steps:
- Network Connection: The device ensures a stable connection to the configured Wi-Fi network.
- Data Transmission: The card ID is packaged into an HTTP request and sent to a remote web server.
- Authentication: A device token is included in the request to ensure the server only processes data from authorized hardware.
- Feedback Loop: The ESP32 waits for a server response. Depending on the server’s logic (e.g., checking if the user is registered), it displays a success or failure message on the OLED screen.
The OLED display acts as the primary interface, showing helpful prompts like “Hello, User!” and “Kindly scan your card” to guide individuals through the process.
Technical Implementation
The firmware is developed using the Arduino framework for ESP32. It relies on several key libraries to manage the complexity of the hardware:
- MFRC522 Library: Handles the low-level SPI communication and protocol requirements for reading RFID tags.
- Adafruit SSD1306: Manages the I2C communication and drawing routines for the 128x64 OLED display.
- ESP32 WiFi & HTTPClient: Provides the stack necessary for connecting to WPA2 networks and performing RESTful API calls.
One of the practical features of the implementation is its resilience; if the Wi-Fi connection drops, the system is designed to attempt reconnection automatically, ensuring that attendance logging remains reliable throughout the day without requiring a manual reset.
Setup and Configuration
To deploy the system, the firmware requires minimal configuration. Users define their Wi-Fi SSID and password, along with the specific URL or IP address of their backend server. This flexibility allows SmartTrack to be integrated into various existing web-based management systems, whether they are hosted locally or in the cloud.