IoT & Security
Embedded System Deployment
Smart RFID Door Access Control & Telemetry System
An IoT-enabled security node combining contact-free RFID credential verification, high-speed Wi-Fi cloud synchronization, and a custom Android monitoring app with instantaneous push event logging.
Core SoC
ESP8266 / NodeMCU Wi-Fi
RFID Reader
MFRC522 (13.56 MHz SPI)
Actuation
12V Solenoid & Relay Circuit
Mobile Companion
Custom Android Application
1. System Architecture & Objectives
Designed to eliminate mechanical key management for restricted laboratory and office spaces. The system authenticates authorized MIFARE RFID tags in under 150 ms, activates electromagnetic locking mechanisms with optocoupled isolation, and logs all timestamped entry events to an online cloud database.
2. Electronics & Hardware Circuitry
- RFID Reader: MFRC522 high-frequency (13.56 MHz) reader interfaced via SPI bus with hardware interrupt triggers.
- Optocoupled Power Switching: Solid-state optoisolated relay driving 12V DC solenoid locks with flyback protection diodes.
- Status Indicators: Multi-color status LEDs, piezoelectric acoustic feedback buzzer, and I2C LCD character display.
3. Cloud Telemetry & Android App
Built with HTTP REST webhooks and MQTT pub/sub channels:
- Real-Time Logging: Every swipe records user ID, timestamp, and verification status (Granted/Denied).
- Android Application: Developed a custom Android client allowing administrators to grant/revoke RFID keycards remotely and trigger instant emergency unlock commands.
ESP8266 SoC
MFRC522 RFID
Android (Java)
IoT Webhooks
Relay Circuitry
Embedded C++