Does co-designing an arm's link lengths and controller beat tuning the controller on a fixed body?
research/osrobot-morph
Does co-designing an arm's link split and controller beat tuning the controller on a fixed body? Co-design gained 1.9% in held-out move time (0.283 against 0.289 s), within three-seed noise; tuning the controller mattered about 37%. Stylised, preliminary, mostly negative.
What it found
A stdlib planar two-link arm model searches the split of a fixed 0.50 m reach together with PD gains, against an equal-link body with tuned gains, at equal search budget. The tray is reachable only for splits of 0.40 to 0.60. Co-design gained 1.9% in held-out move time (0.283 against 0.289 s), within three-seed noise, while tuning the controller cut hand-set gains' 0.460 s by about 37%. Stylised, preliminary and mostly negative: one body parameter and an assumed torque limit.
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.