origami CAD: describe a force response, get back a verified fold pattern
This repository holds only work done during the Meta Global AI Developer Hackathon (from 2026-10-26, 11:00
America/Chicago). It builds on earlier code (the simulator, generators, world models, census and proposer v0/v0.5),
which lives in a separate repository, origami-world-model-prior,
and is fetched by scripts/setup_prior.sh (setup). What came before and what was built this week:
below and HACKATHON.md.
A pipeline that designs origami-inspired programmable force-response metamaterials from natural language. These are
folded cells whose force–displacement curve is designed: a flat force plateau over a set stroke, a click at a set
travel, resistance in stages, or a set of shapes the cell holds by itself. They recover elastically, so the part can be
used again. You type or say the curve you need, in your own words and numbers. Meta's Muse Spark turns that into
precise checks and plans which fold-pattern families to try. The pipeline searches and tunes crease layouts across
those families on a physics simulator. You get back a crease pattern whose behaviour the simulator has verified and
stress-tested, with a datasheet saying how far each number can be trusted, or an honest "not found within budget".
- Project overview: docs/overview.md: what the pipeline does, what these metamaterials are,
how engineers design them today, the bottlenecks, how the pipeline works, and next steps.
- Live app: https://raphaeldchen--origami-cad-web.us-east.modal.run/
- Designs from tonight's runs: Force-Response Designs: requests,
3D motion, force curves and crease patterns.
- Built for: Meta Global AI Developer Hackathon, theme "Push the Frontier" (Oct 26 – Nov 4, 2026).
- What was built during the hackathon, and what before: HACKATHON.md (summary below).
- The plan in plain language: docs/plan.md.
Example (live app, 2026-11-02, run r-e151c1ef). Request: "I want a pad that pushes back with the same force, about
5 N, from 20 % to 50 % of its travel, whatever the exact thickness of the part it clamps, and springs back fully when
released." Muse Spark mapped it to force_plateau (window 0.2–0.5 of the stroke) and springs_back, and listed the
5 N as unchecked (forces are relative). The planner tried four families. A tiling layout met both checks robustly: 10 of
10 perturbed copies and 3 of 3 nudged runs, 57 simulator calls, 7 minutes and $0.02 of compute. "Verified" means
verified by our simulator; forces in tiling layouts have not yet been checked against experiment.
At a glance
| Question | Answer today (2026-11-02) |
|---|
| What does it design? | Force–displacement shapes (plateaus, clicks, staged and equal-force steps), multistable held shapes and heights, push–pull switching, stiffness switching and Poisson-programmed cores. All are quasi-static and elastic. |
| How often does it succeed? | On 8 force-response requests swept over 3 seeds, a planned run returned a robust, simulator-verified design in 17 of 24 runs at 120 simulator calls, and 17 of 24 at 360 calls (sweep). |
| Does it design new crease layouts? | It searches 8 families at once. These include tilings and mixed-vertex sheets outside the standard catalog, plus Kresling towers where a known family suffices. It composes and tunes layouts within those families' grammars, and doesn't claim new pattern classes. |
| Who decides that a design works? | The physics simulator, always, including a robustness test: refined run, 3 nudged runs, 8 of 10 perturbed copies. Muse Spark translates, plans and explains, but never grades a result. |
| How far can the numbers be trusted? | The Kresling family is validated against experiment (Zang et al., PNAS 2025). Other families agree with theory or are not yet validated, and the datasheet tags each. Forces are relative; newton units are validated on framed Kresling but not yet live. |
| Is the learned world model in the search loop? | No, not yet. No world model has passed its held-out gates on grids (see The world model). The search runs on the simulator alone, and the app's pipeline strip says "skipped". |
| Can I download the pattern? | Yes: FOLD v1.2 and an SVG cut-and-score file, but only for simulator-verified designs. |
| Has it been folded in real paper? | Not yet. A bench protocol for paper stiffness is prepared; no CAD design has been folded and measured. |
Why it matters
Force-response metamaterials get their behaviour from geometry rather than from the material. A folded paper cell can
hold a part at constant force, give a gloved finger a click, or count presses without electronics. Engineers specify
the curve they want, but designing a fold pattern that delivers it is still done by hand:
This is the beginning of the README. Read the rest at the original. Read the full README ↗
