Does the feeding arm's tip pressure, not its force, break the ISO/TS 15066 face limits?
research/osrobot-mjpress
A 4 mm feeding-arm tip that meets the 65 N face force limit still needs 0.5 to 2.7 cm² of contact to meet a 110 to 20 N/cm² pressure limit at its worst trial (53 N); the answer flips on an unsourced face modulus (MuJoCo, simulation only)
What it found
osrobot-mjface found every camera-arm trial under the 65 N face force limit (worst 53.3 N) but did not apply pressure limits. This project divides the same 200-seed peak forces by a swept contact area. The worst trial needs 0.48 cm² to stay within 110 N/cm², 0.97 cm² within 55 and 2.67 cm² within 20; a Hertz contact of the 4 mm tip gives 0.41, 1.93 or 8.9 cm² for a face modulus of 5, 0.5 or 0.05 MPa, so the verdict depends on a modulus that is not sourced. Lightly damped contact (b = 4 to 100) needs a third of the area of b = 1000. Pressure limits (20, 55, 110 N/cm²) are from conflicting secondary excerpts and not confirmed; damping, modulus, tip mass, gains and sway are assumed; lips are kinematic. Simulation only, not a safety case.
A figure from its own output
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.