Is any rate threshold settings-robust for a MuJoCo grasp "holds" verdict?

research/robofab-slipthresh

Is any rate threshold settings-robust for a MuJoCo "holds" verdict? Spread falls with the allowed tip speed and is 1.6 only at a loose 20 mm/s (0.5 s, 10 mm); 242.7 to 400 at 2 mm/s or less (stylised, preliminary).

6 tests

What it found

A follow-up to robofab-slipcrit that sweeps the rate criterion’s task time (0.5–10 s) and tip bound (1–10 mm) over four bars and eight MuJoCo contact settings. The worst-case spread of the minimum holding force falls with the allowed tip speed: 242.7–400× at 2 mm/s or less, 89.4× at 3.3–5 mm/s, 20× at 10 mm/s and 1.6× only at 20 mm/s (0.5 s, 10 mm), a loose threshold; 10 s holds fail at every bound. Robustness comes from a loose threshold, not a better criterion. Stylised and preliminary: one engine, boxes, assumed density and friction.

A figure from its own output

Figure produced by research/robofab-slipthresh: spread — robofab-slipthresh/experiments/spread.svg, written by the project's own experiment code.

Paper, code and results

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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.