# Secondary designs — recovery notes (2026-07-06)

Recovered verbatim above: gripper pipeline, arm variants (beauty/aligned/detach/curvy/two_servo core),
camera, gravity-comp (gen_cb + compute_cb), gantry structure (gen_gantry), linear rail (both files),
render_arm (reconstructed), composer (gen_arm_gripper).

NOT re-dumped as code (still fully described in docs + rebuildable in <1h each when needed — they are
concept URDFs with no downstream dependencies):
- gen_nema.py — NEMA17 (42.3mm body, 5mm shaft, 4x M3 @31mm, 22mm boss) + motor mount (50x50x5 plate,
  M5 foot holes) + T8 leadscrew + nut-block (8.2 bore, 2x M3) + MGN12 rail (12x8) + GT2 pulleys/belts →
  gantry_arm_motorized.urdf. Params in docs/gantry/BILL_OF_MATERIALS.md + WIRING.md (on lab; content also
  in agent memory/summary).
- gen_carriage.py — carriage_plate.stl 50x40x13: MGN12H seat (4x M3 @20x15), GT2 belt clamp ridge (slot +
  2x M3 @ x±20,y16), 4x M4 next-axis holes @36x28.
- gen_wrist_bracket.py — gantry_wrist_bracket.stl 56x48x32: top M4 @36x28 to carriage, bottom M3 @32x18
  to STS3215 holder + Ø14 output clearance, 2 side skirts.
- gen_mobile.py v2 — diff-drive base (2 driven wheels r60 @x±0.21 + 2 sphere casters @z±0.13), chassis
  0.40x0.10x0.30, 2040 mast 0.85 @z-0.13, prismatic lift 0..0.65, 4-DOF forward arm, world Y-up joint.
- gen_mobile_gantry.py — chassis 0.45x0.35 + 4 wheels r50 @(±0.20,±0.15) + compact portal (legs ±0.18
  h0.50, top rail 0.44 @0.65) + prismatic X±0.15/Z±0.13/Y0..-0.32 + tool.
- struct_analysis.py / struct_beams.py — full source recoverable from agent transcript if needed; key
  RESULTS live in docs/arm/README.md (shoulder 52% stall @12V, wobble budget, SF>=15).
- render helpers (render_detach/coupon/platezoom/gripper_multi) — trivial mujoco snippets, rebuild on demand.

Lab-only (re-pull when phe108 returns): apply_glb_layout.py, fillet_holder.py, yoke_exact.py, carve_holder.py,
make_mjcf.py, build_sidebyside.py, build_mj_bundle.py, add_fidex.py, gen_fiducial.py, snap_analyze.py,
mj_stuff/, all smith300_* history, GRIPPER_PLAN/LOG, docs/ tree, the cad viewer app.