Project Hub /Communication Systems/RF Remote Control Systems/Turn Your Phone Into IR Contactless Thermometer

Intermediate

ARDUINO

₹1,500 – ₹5,000

3 – 6 Hours

Partial Kit

Turn Your Phone Into IR Contactless Thermometer

Develop a smart Bluetooth-based contactless IR thermometer with thermal screening capabilities that connects directly to your smartphone.

Originally published on ElectronicsForU

View original tutorial

Parts You'll Need

This project is sourced from another site, not written by us — this list is our best match of their components against what we stock, not a verified bill of materials. Always check the original blog (linked above) for the actual parts list before buying.

ESP32 WiFi+Bluetooth CP2102 Development Board Rs. 520.00
0.96 Inch I2C/IIC 4pin OLED Display Module White Rs. 349.00
Jumper Wire 10 Pin Male To Male 20cm Rs. 45.00
MB102 Adjustable Breadboard Power Supply Module (3.3V & 5V) for Arduino & Raspberry Pi Rs. 139.00
400 Points Mini Solderless Prototype PCB Breadboard High Quality Rs. 89.00
Jumper Wire 10 Pin Male To Female 20cm Rs. 45.00

Selected: Rs. 0.00

We don't carry yet: Arduino (unspecified board)
Temperature Sensor (generic)

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How It Works

The Turn Your Phone Into IR Contactless Thermometer project integrates thermal sensing with wireless communication by centering its architecture around an Arduino Uno microcontroller. At the heart of the hardware setup is the MLX90614 infrared temperature sensor, which measures surface temperature without physical contact by detecting the infrared energy emitted by an object. The sensor communicates ambient and object temperature data back to the Arduino using the I2C protocol. Once the Arduino processes these digital temperature readings, it transmits the data outward using an HC-05 Bluetooth module via serial communication. A custom mobile application, built using Kodular, pairs with the HC-05 module to receive the temperature data in real time, displaying the thermal metrics directly on a smartphone screen. An optional OLED display can also be wired to the Arduino's I2C bus to provide a local readout alongside the smartphone display. Power is supplied by an independent power source, while connecting wires complete the necessary power, ground, and data pathways between the microcontroller and peripherals. The Arduino IDE is used to write, compile, and upload the embedded C++ control logic that coordinates sensor polling, data formatting, and wireless transmission.

Why Build This

Design an embedded thermal screening system capable of wirelessly transmitting contactless temperature data to a mobile interface for public health monitoring.

Gain practical undergraduate-level experience integrating I2C sensor peripherals with Bluetooth serial modules on an Arduino microcontroller.

Develop custom Android applications using visual block-based tools like Kodular to interface external hardware with smartphone displays.

Real-World Application

Useful for screening body temperatures in public spaces, offices, and healthcare settings to monitor and prevent the spread of infectious diseases like COVID-19 without physical contact.

Skills You'll Learn

I2C sensor communication

Bluetooth serial interfacing

microcontroller firmware development

mobile application UI design

contactless infrared temperature measurement

Safety Precautions

Ensure proper wiring of power and ground connections to prevent short circuits. Maintain safe handling practices when working with electronic components and soldering irons.

Technology Tags

ARDUINO

BLUETOOTH

IR SENSOR

MLX90614

MOBILE APP DEVELOPMENT

KODULAR

THERMAL SCREENING

CONTACTLESS THERMOMETER

Frequently Asked Questions

Can I view the temperature readings without using a smartphone?

Yes, you can integrate an optional OLED display wired directly to the Arduino's I2C pins to show local temperature measurements alongside the Bluetooth transmission.

How does the smartphone communicate with the Arduino?

The smartphone pairs wirelessly via Bluetooth to the HC-05 module connected to the Arduino's serial pins, receiving the processed temperature data sent by the microcontroller.

What software is needed to build the mobile app?

The mobile app is created using Kodular, a web-based, block-programming environment designed for building custom Android applications with Bluetooth connectivity.

Gallery

This page is part of Kitkraft's Project Hub — a curated collection of electronics & robotics projects gathered from the maker community to help students and hobbyists discover and learn to build. Kitkraft does not claim authorship of the original project, and makes no representation as to the accuracy, completeness or safety of third-party source material. The summary and "How It Works" explanation above are AI-generated, rewritten with reference to the original tutorial — not a reproduction of it. Full credit and a direct link to the original source are provided above. If you're the original creator and have a concern about how your work is represented here, please contact us and we'll address it promptly.

Kitkraft Project Hub — curated from the maker community, credited at the source.

PRJ-00249