What hanger shape keeps a shirt in shape, and can one hanger fit every size?

research/hanger-fit

What hanger shape keeps a shirt in shape, and can one hanger fit every size for a laundry-hanging robot? In a 2D cloth-drape simulation the best single fixed hanger leaves garments 2.1 cm RMS from their worn shape (5.4 cm for a child's tee), one adjustable-width hanger set per garment 0.18 cm, and a rack of four widths under 1 cm for every size; thin wire ends fold the cloth at the tip. Stylised.

14 tests

What it found

A 2D cloth-drape model (discrete elastic chain with penalty contact, solved by L-BFGS) scores how far a garment hangs from its worn shape, and CMA-ES designs the hanger. Over seven sizes from a child’s tee to XXL, the best single fixed hanger averages 2.1 cm RMS shape error (5.4 cm worst). One adjustable-width hanger set per garment averages 0.18 cm (0.22 worst), 12× better, and a rack of four widths keeps every size within 1 cm. Wire and plastic hangers fold the cloth at the tip (about 65°/cm against 14° worn); a 2–3 cm round end removes it, but a loop scored on shape alone converges on wire-thin ends. CMA-ES beats random search (0.19 vs 0.44 cm at 150 drapes). Stylised: 2D, no friction, assumed fabric constants.

A figure from its own output

Figure produced by research/hanger-fit: drape — hanger-fit/experiments/drape.svg, written by the project's own experiment code.

Paper, code and results

More in Laundry-hanging robots

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Other research topics

Proper scoring & elicitation28 Effort & peer prediction9 Verification games & slashing19 Detection & tolerances14 Markets as routers13 Prediction-market design9 Paying contributors8 Decentralised training systems23 Digital twins & sim-to-real164 LLM chip design loops40 Robot manufacturing loops53 Ambient AI assistant46 Self-replicating manufacturing34 Simulation-first design64 Engineered clothing45 Task-specific AI accelerators40 Algorithmic chip-design loops42 Open-source purpose-built robots44 The software-engineering loop43 Adversarial human imitation41 Open-source residential construction41 Autonomous multi-angle capture34 Sensing, imaging and 3D31 Energy supply and dense energy storage39 Robot societies among people31 Agentic co-design of low-cost robots27 Laundry-hanging robots25 Machine learning on qualitative data23 Robots on the building site27 Civilizations & group psychology1 History & human sciences1

Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.