Is the least-mass laser-cut bracket the same on coarse and fine meshes under a patch-averaged stress rule?
research/simdesign-gaugefine
Under a 3 mm patch-averaged stress rule the least-mass laser-cut bracket is the same on a 2.5 mm and a 1.0 mm mesh (gauge 2: 32.31 vs 32.33 g), while the centroid-peak rule leaves no feasible gauge-2 design on the fine mesh; the patch value hardly sees the fillet radius; stylised, preliminary.
What it found
Preliminary, stylised 2D plane stress. On a 20×20 grid over arm width and fillet radius, the least mass of a feasible laser-cut bracket under a 3 mm patch-averaged stress rule is the same on a 2.5 mm and a 1.0 mm mesh (2 mm sheet: 32.31 vs 32.33 g; 3 mm: 40.81 vs 40.81 g). Under the element-centroid peak rule the 2 mm sheet has no feasible design on the fine mesh and the 3 mm sheet needs 10.8% more mass. The catch: the patch value hardly depends on the fillet radius (94–102 MPa for r from 0 to 15 mm against a peak of 126–264 MPa), so the rule cannot tell a sharp corner from a generous fillet. Two meshes only; one load case; nothing built or tested.
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.