How wide should domain randomization be, and what does it buy?

research/randomized-twin

Domain randomization over a twin, exactly: cliff-limited width, quartic price when the twin was right, cliff pushed out ~15%, but uniform-average training is not minimax and the best width tracks the prior.

9 tests

What it found

Randomizing the twin's input gain over ±ε trains a more conservative gain (monotone in ε; small-width law k_ε−k* = −(εb)²J_kbb/(6J_kk)) at a quartic price when the twin was right, and moves the deployment stability cliff out by about 15%. At 2.3× the twin's gain the nominal controller has regret 84 versus 1.4 at ε=0.9. But uniform-average training is not minimax: its worst-case regret exceeds the nominal gain's for ε ≤ 0.7, and the best width equals the prior's half-width, paying off only when the prior reaches the cliff. Stylised.

A figure from its own output

Figure produced by research/randomized-twin: regret — randomized-twin/experiments/regret.svg, written by the project's own experiment code.

Paper, code and results

More in Digital twins & sim-to-real

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Does a more robust CFAR detector survive a Gaussian-clutter radar simulator?Does a more robust CFAR survive a Gaussian-clutter twin? CA, OS and log-t all inflate 8–44× at design 1e-4 (no detector escapes), a known-scale oracle inflates as much as CA (the test cell's own texture), and CA detects best at equal real Pfa after repair.

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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.