In this project we are going to build and IoT Based Biometric Security System using the GT5111C3 fingerprint sensor, NodeMCU and Solenoid lock. Adafruit IO is used to save the entry details online while IFTTT is used to send the Email notifications when an unauthorised person scans the finger on the fingerprint sensor.

The circuit for this IoT based Biometric Security System consists of a NodeMCU, GT511C3 Fingerprint Sensor, Solenoid Lock, Relay Module and Buzzer. VCC and GND pin of Fingerprint sensor are connected to 3.3V and GND pin of NodeMCU while TX and RX pins are connected to D6 and D5 pins of NodeMCU. Positive pin of the buzzer is connected to D2 pin of NodeMCU, and the negative pin is connected to GND of NodeMCU. The solenoid lock is connected to NodeMCU through the relay module. The NodeMCU and Solenoid Lock both are powered with 12V Adapter.




Adafruit IO is an IoT platform that allows you to visualise, and analyse live data on the cloud.  Using Adafruit IO, you can control motors, read sensor data, and make cool IoT applications over the internet. In this project, we are sending the Entry details to Adafruit IO Dashboard.


View the full DIY project tutorial with code and circuit