Does the loose 20 mm/s “holds” threshold stay settings-robust at other friction and under lift?

What it found

A follow-up to robofab-slipthresh, repeating its 16-threshold sweep at friction 0.3, 0.5 and 0.8, with and without a 5 m/s² lift acceleration. The loose 20 mm/s threshold (10 mm in 0.5 s) is the only one with a worst-case spread of the minimum holding force under 5× in all six conditions: 1.6× in four, 2.7× at mu 0.5 with lift and 4.5× at mu 0.3 with lift. Every other threshold is at least 20×. Robustness comes from looseness, and it weakens at low friction under load. 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

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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.