# Sapa

- **Event:** [Meta Global AI Developer Hackathon](https://cerebralvalley.ai/e/meta-ai-developer-hackathon)
- **When:** Oct 26, 12:00 PM – Nov 4, 9:00 PM (EST)
- **Where:** Online
- **Team:** [Nikolas Sapalidis](https://cerebralvalley.ai/u/nikolas_sapa)
- **GitHub:** https://github.com/nikolas-sapa/motionforge
- **Demo video:** https://youtu.be/jpR7Zbpi3nQ
- **Gallery:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery
- **Page:** https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2943

MotionForge turns filmed movement into reusable, interactive JavaScript springs.

Frontend and game developers often hand-tune animation parameters. MotionForge offers a measured starting point: upload a short, fixed-camera video, select one moving object, and use Meta SAM 3.1 to track it. A deterministic fitter estimates a supported damped oscillation from the tracked bounding-box centers.

Developers can inspect measured-versus-fitted motion, then test the resulting spring on a dot, button, or toast. Dragging and releasing supplies new initial conditions while the source video stays paused.

The exported, dependency-free JavaScript contains coefficients and equations, not a recorded position path.

**Built for:** Meta Global AI Developer Hackathon 2026  
**Track:** Push the Frontier

**Prototype validation**

- Validated on one physical oscillator clip.
- 240/240 frames successfully tracked.
- Approximately 1.12% interleaved holdout normalized error.

**Limitations**

This measures agreement within the observed clip, not future predictive accuracy. Bounding-box centers approximate screen-space motion; true physical mass and stiffness are not recovered. Arbitrary trajectories remain outside the supported motion family.

## More from Meta Global AI Developer Hackathon

- [PixieLearn](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2940)
- [mentalist](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2941)
- [NOIR](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2942)
- [h-hu](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2944)
- [Stashov](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2945)
- [Undesign](https://cerebralvalley.ai/e/meta-ai-developer-hackathon/hackathon/gallery/2946)

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