Does a framing nailer's recoil knock a stock Unitree G1 arm off the stud window?
research/buildbot-recoil
Does a framing nailer's recoil knock a stock Unitree G1 arm off the stud window? In a closed-loop MuJoCo hold, up to 4 N s of recoil moves the tip 1-4 mm (window +-3.9 mm) but 1 N s or more lifts the nosepiece off the wall for 25-140 ms; stiff loops go unstable with 10-20 ms delay (recoil, delay and wall are swept, not sourced).
What it found
A closed-loop MuJoCo check on the Menagerie G1 holding a 3.4 kg nailer against a wall (pelvis fixed, no legs). A half-sine recoil impulse hits the tip; the sweep covers impulse (0.25–8 N s), loop bandwidth (2–12 Hz), delay (0–20 ms), wall stiffness and preload. Up to 4 N s the tip stays within 1–4 mm of its place (joint-nail window ±3.9 mm) for 4–12 Hz loops, but an impulse of 1 N s or more lifts the nosepiece off the wall for 25–140 ms, and stiff loops go unstable with 10–20 ms of delay. The recoil of a real nailer, the G1's loop delay, the wall stiffness and damping, and the 4 ms pulse are not sourced (swept or assumed); legs and balance are not modelled.
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.