Project Hub /Automotive EV & Transportation/Smart Vehicle Safety & ADAS/Cheapest Digital Altimeter

Beginner

ARDUINO

₹500 – ₹1,500

3 – 6 Hours

Partial Kit

Cheapest Digital Altimeter

Build a low-cost digital altimeter using an Arduino and a BMP280 sensor to calculate altitude based on atmospheric pressure and display it on an OLED screen.

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.

GY-BMP280-3.3 HIGH PRECISION ATMOSPHERIC PRESSURE SENSOR MODULE Rs. 69.00
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)

Browse all components

How It Works

The Cheapest Digital Altimeter project operates by measuring ambient barometric pressure and converting that data into an estimated altitude. At the heart of the system is the BMP280 sensor, which communicates with the Arduino Uno microcontroller using the I2C communication protocol. As altitude changes, atmospheric pressure changes inversely—air pressure decreases as you ascend. The BMP280 samples this barometric pressure and transmits the raw numerical data back to the Arduino over the I2C serial interface. The Arduino runs a software sketch compiled in the Arduino IDE, utilizing the specialized BMP280 library to process the raw pressure readings. By applying the barometric formula, which correlates pressure changes with height relative to a sea-level baseline, the microcontroller calculates the current altitude in real time. Once computed, the Arduino formats this numerical altitude data and sends it over the same I2C bus to a connected OLED display. The U8g2 library handles the graphical rendering on the OLED screen, ensuring crisp, readable text output of the calculated altitude values for the user.

Why Build This

Gain practical experience implementing the I2C protocol to daisy-chain multiple digital sensors and displays to a single microcontroller.

Understand the mathematical relationship between barometric pressure and altitude for environmental sensing and aerospace applications.

Prototype a complete embedded data-logging or measurement device suitable for integration into drones, high-altitude balloons, or portable tracking systems.

Real-World Application

Used in flight systems, drones, paragliding, high-altitude balloons, weather monitoring, indoor positioning, and elevator floor tracking where GPS altitude is insufficient.

Skills You'll Learn

I2C bus communication

barometric pressure data processing

library integration in Arduino IDE

sensor calibration and baseline referencing

OLED display rendering

Safety Precautions

No specific precautions noted for this build — always follow general electronics safety practices.

Technology Tags

ARDUINO

BMP280

OLED DISPLAY

U8G2 LIBRARY

I2C

ALTIMETRY

SENSORS

PRESSURE SENSOR

TEMPERATURE SENSOR

Frequently Asked Questions

Why does the altitude reading fluctuate slightly even when the sensor is completely stationary?

Atmospheric pressure naturally fluctuates due to micro-weather changes, wind gusts, and indoor HVAC air currents, which the sensitive BMP280 detects as minor altitude shifts.

Can I power this entire circuit using a standard 9V battery plugged into the Arduino?

Yes, an Arduino Uno can accept a 9V battery via its barrel jack or VIN pin, and its onboard voltage regulator will step it down safely to the 3.3V or 5V required by the BMP280 and OLED display.

Do I need to change any wiring if my OLED display and BMP280 sensor use the same I2C address?

Most BMP280 sensors and I2C OLED displays use different default addresses (commonly 0x76 or 0x77 for the sensor and 0x3C for the display), allowing them to share the exact same SDA and SCL pins on the Arduino without conflict.

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.

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