Does the lightest 1.5 mm bracket design clear buckling in a converged 3D eigenbuckling model?
research/simdesign-buckle15
A through-thickness-converged 3D eigenbuckling model agrees with the closed-form buckling factor of the lightest 1.5 mm bracket design to under 1% (3.49 vs 3.47, so it clears the floor of 3); the horizontal-arm formula is about 18% conservative; one design, ideal bar, preliminary.
What it found
A small finite-element check (stylised, preliminary; ideal elastic clamped arms, one design). Meshing the 1.5 mm, w = 18.4 mm design from simdesign-bucklebound with hexahedra at three resolutions, including two layers through the thickness, the governing vertical-arm buckling factor is 3.49 against 3.47 from the closed form (ratio 1.020 → 1.007 on refinement), so the design clears the floor of 3. The horizontal-arm formula is about 18% conservative. Nothing was made or tested.
A figure from its own output
Paper, code and results
More in Simulation-first design
- What changes when the w/b ≤ 8 slenderness ceiling of the laser-cut bracket is replaced by a buckling-factor floor?Replacing the w/b ≤ 8 ceiling with a closed-form buckling-factor floor makes the 1.5 mm laser-cut gauge feasible (31.0 g, about 13% lighter than the best 2 mm design) and changes nothing at 2 and 3 mm; at 1 mm the minimum-wall rule, not buckling, blocks every design; stylised, unvalidated factor, preliminary.
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- How much stiffer than a uniformly thinned plate is a topology-optimised part, and how does that depend on volume fraction?How much stiffer a thresholded topology-optimised part is than a uniformly thinned plate across volume fractions (stylised): 26–31% lower compliance at v = 0.3–0.5, shrinking to 14% at 0.8, and disconnected designs below that on coarse grids.
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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.