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Known gap: trapped air under a label is scored at 20 mm², not GA's 3 mm² inside a barcode

What is wrong

  • The bonds plug-in's trapped-air pockets (Bonds.Config.trapped_air, alloy/plugins/bonds/air.py) resolve a pocket to the label's mesh cells. GA's label criteria ask for no trapped air larger than 20 mm² over the label and no larger than 3 mm² inside its barcode.
  • Label stock (60 µm BOPP) behaves at 2 mm cells, where one cell is 4 mm². So the 20 mm² criterion is scored (about 5 cells), and the 3 mm² barcode criterion is not: a 3 mm² pocket is smaller than one cell.
  • Each label task's result says barcode trapped-air: not scored (needs < 1.5 mm cells; 60 µm stock freezes below that) (air.BARCODE_NOT_SCORED), and the task counts as partial on that criterion. No binary proxy stands in for it (coordinator ruling, 2026-11-08 05:40Z).

Number

B2 resolution check (WP8's write-up of 2026-11-08, not shipped), 60 µm BOPP (E 2 GPa ESTIMATE), film route as shipped (dt 1 ms, 10 VBD iterations), CPU, built near z = 0: - a 20 mm cantilever sags 0.96-1.07x plate theory at 2 mm cells; 1.5 mm cells sag about 20 % stiff and ring; 1 mm cells are iteration-dependent and settle 3x too stiff (0.08 mm for 0.25); 0.5 mm cells do not move; - a pad press at 2x the bond pressure bonds the whole label at 2 and 1.5 mm cells and nothing at 1 mm; - scoring 3 mm² needs cells of about 0.7 mm or finer.

Why

The film route's bending stiffness converges ever more slowly as cells shrink: stiffness relative to inertia grows as D/ℓ⁴, so at fixed iterations a fine sheet of stiff stock is effectively frozen. Built far from the origin, float32 positions freeze it sooner (the ulp at 0.5 m swallows each step's move), so label scenes are built near z = 0.

Workaround

  • Score the 20 mm² criterion at 2 mm cells (the pocket rig's laws T-1 and T-2 run there) and report the barcode criterion as not scored.
  • A thinner or softer stock, or a barcode region meshed finer, does not help today: the stock itself freezes.

Planned fix

A film-solver item (the film route, WP4, engine item 8): bending that converges at sub-millimetre cells for stiff stock (a multigrid or Chebyshev-accelerated bending solve, or a hinge model whose stiffness does not grow as D/ℓ⁴ per iteration), checked by the B2 resolution probe (a 60 µm BOPP cantilever within 5 % of plate theory at 0.7 mm cells, and a pad press that bonds there). Then the pocket model scores the 3 mm² criterion unchanged. Not scheduled.