UPDATE: In May 2025, the project achieved recognition by winning 1st prize in the Instructables contest All Things Pi. A big thank you to the Instructables teams!

I have recently published another educational project on my Instructables website. I called the device RaPenduLa for the RaspPi Pendulum Laboratory, and it is a video platform for studying mechanical oscillations. It uses a Raspberry Pi Zero W2 equipped with a camera module to record the motion of pendulums in high speed. The interesting part happens through video analysis: using Python and the fantastic OpenCV library, RaPenduLa can track the precise path of a pendulum’s tip and help visualize its oscillatory behavior in two dimensions.

In short, RaPenduLa is:

• A modular, 3D-printable platform that supports various pendulum configurations — from simple magnetic pendulums to more complex inverted spring systems.
• A video capture and analysis system using a Raspberry Pi camera module.
• A teaching and learning tool ideal for science fairs, university labs, and physics demonstrations.

All of the components are easy to source — many from recycled or common household items — and detailed instructions and 3D-print files are included in the Instructable. If you have access to a 3D printer and enjoy hands-on projects, you’re all set.

How It Works

Once assembled, the platform lets you record high-framerate videos of pendulum motion. A red marker attached to the tip of the pendulum is tracked frame-by-frame using a simple Python program with a graphical interface. The software filters the video to isolate the marker’s color and then plots its movement across time. The result? A clear, quantitative visualization of the pendulum’s dynamics.

The system supports real-time tweaking of parameters like HSV filtering, making it highly adaptable for different lighting conditions or marker colors. The software even allows you to trim the video range and export data for further analysis.

Why Build It?

There are many reasons why RaPenduLa could be a great addition to your teaching toolkit or maker bench:

• For students: It offers a fun, tangible way to learn about harmonic motion, damping, resonance, and chaotic behavior in pendulum systems.
• For teachers: It serves as a ready-to-go lab module with digital tracking tools included.
• For hobbyists: It’s a rewarding build that combines electronics, mechanics, and coding — perfect for makers interested in physics or motion analysis.

Whether you’re analyzing a simple harmonic oscillator or diving into chaotic dynamics with a magnetic pendulum, this platform is designed to be both educational and engaging.

You can find the complete build guide here:

👉 The RaPenduLa on Instructables

If you do end up making your own version or adapting it for a new kind of experiment, I’d love to hear about it. Feel free to leave a comment or get in touch!

Happy oscillating!