Ballistic Pendulum Lab Equipment Prototype

This is a low-cost ballistic pendulum demo designed for classroom use. It demonstrates momentum and energy transfer in inelastic collisions. A small projectile is launched using a rubber band-powered mechanism into a pendulum arm, which captures it and swings upward. The swing height can then be measured to calculate the initial momentum of the projectile.

The device is built from PETG 3D-printed parts, held together with super glue, and uses 6mm x 3mm magnets for alignment and retention in some components. The total cost stays under $20 by using household materials and simple printed parts.

This prototype is not fully refined: the ratcheting system for the pendulum arm doesn’t reliably hold, the launcher release needs smoother operation, and the projectile pin could be improved for consistent launches. Still, it may serve as a useful starting point for others building a similar device.

How to Use:

1. Load the projectile and stretch the rubber band launcher.
2. Secure it using the trigger mechanism.
3. Align the pendulum arm to catch the projectile.
4. Release the trigger to launch.
5. Measure the pendulum’s swing height to analyze momentum transfer.

This project is part of a senior capstone focused on creating accessible, hands-on physics demos using affordable materials.