Does a rate-based "holds" criterion make a MuJoCo grasp verdict independent of solver settings?

What it found

A follow-up to robofab-sliprate. Judging a bar held at one end by its extrapolated creep over a 3 s hold (under 2 mm) instead of a rotation tolerance does not help: across eight MuJoCo contact settings the minimum holding force varies by 33× to 400× or more, about as much as under a 1° tolerance. Only a loose 5° tolerance is stable, and only for bars up to 40 mm. Negative and preliminary: the settings, not the criterion, drive the verdict. Stylised, one engine, no physical grip.

A figure from its own output

Paper, code and results

• README and method
• White paper
• Experiments and results
• Code
• Tests

More in Robot manufacturing loops

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Proper scoring & elicitation28Effort & peer prediction9Verification games & slashing19Detection & tolerances14Markets as routers13Prediction-market design9Paying contributors8Decentralised training systems23Digital twins & sim-to-real164LLM chip design loops40Robot manufacturing loops53Ambient AI assistant46Self-replicating manufacturing34Simulation-first design64Engineered clothing45Task-specific AI accelerators40Algorithmic chip-design loops42Open-source purpose-built robots44The software-engineering loop43Adversarial human imitation41Open-source residential construction41Autonomous multi-angle capture34Sensing, imaging and 3D31Energy supply and dense energy storage39Robot societies among people31Agentic co-design of low-cost robots27Laundry-hanging robots25Machine learning on qualitative data23Robots on the building site27Civilizations & group psychology1History & 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.