ThermaLog Gun V2

Features

RFID-Based User Identification: Reads unique user ID using RFID cards/tags.
Contactless Temperature Measurement: Uses the MLX90614 infrared sensor to measure body temperature without physical contact.
Automated Cloud Logging: ESP32 pushes User ID + Temperature + Timestamp directly to Google Sheets using the Google Sheets API.
Wireless & Portable: No PC required, works via Wi-Fi through ESP32.
Real-Time Monitoring: Data appears instantly in Google Sheets for analysis or future reference.

Components Used

ESP32, Main microcontroller with Wi-Fi and Bluetooth support
MLX90614 (Infrared Temperature Sensor), Measures body temperature without physical contact
RFID RC522 Module, Reads RFID card/tag UID for user identification
OLED Display, Displays the scanned user ID and temperature
Buzzer + Push Button, Used for feedback and user interaction
Google Sheets API, Stores data (RFID UID + Temperature + Timestamp) in the cloud
Jumper Wires + Breadboard, Used for wiring and prototyping during the testing phase

How it Works

User taps/scans their RFID card on the RC522 RFID module.
ESP32 reads the unique RFID UID.
MLX90614 measures the temperature without touching the user.
ESP32 uploads the captured data to Google Sheets in the format:
→ RFID UID + Temperature + Timestamp
Data updates in real-time and can be viewed from anywhere.

Current Status (Prototype Tested)

RFID scanning + temperature sensing + cloud logging successfully tested on ESP32.
The system uploads data properly to Google Sheets.
Project was tested only on a breadboard prototype.
The project was paused before enclosure and final hardware build due to exams.

Media Availability (Important Note)

This was an old project, and at that time I wasn’t documenting builds properly.
I do not have many photos or videos of this version, only one video of the serial monitor output showing RFID + temperature logging working.

Working

Code & Installation

The complete source code is available in the GitHub repository.

View on github ->

My Learnings

Interfacing RFID RC522 with ESP32
Combining multiple modules (RFID + MLX90614 + OLED)
Sending structured data to Google Sheets API
Working with APIs, authentication, and cloud logging
Managing multiple sensors together on the ESP32 platform