Does the filter radius or the threshold gap set the minimum feature size of a robust topology-optimised beam?
research/simdesign-robustradius
Does the filter radius or the threshold gap set a robust beam's minimum feature size? A gap of 0.1 already stops the erosion failure (eroded compliance 255–276 against 187–200 nominal; plain design disconnects), but solid feature size is 3 px at both radius 4 and 6 (negative; stylised, one mesh).
What it found
Sweeps filter radius (2, 4, 6 elements) against threshold gap Δη (0, 0.1, 0.2) on a half-MBB beam, 120×40 elements, nine designs each judged at thresholds 0.7, 0.5 and 0.3. A gap of 0.1 already stops the erosion failure: eroded compliance 255–276 against 187–200 nominal, where the plain Heaviside design disconnects (107–109). The radius does not give a clean length-scale control by the opening-rule measure: solid feature size is 3 px at both radius 4 and 6. Stylised: one problem, one mesh, one run per cell, integer-pixel measure.
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.