How much does a SIMP topology optimisation depend on its starting density field, and does penalty continuation remove it?

What it found

Half-MBB, volume 0.5, p = 3, 150 sensitivity-filtered OC iterations, 30 random starting fields at each of three noise levels on two meshes, with and without penalty continuation (1 → 3). With a fixed penalty the final compliance spreads by 1.4–2.8% (max/min − 1) and the 0/1 design differs from the uniform-start design in a median 2–23% of elements, with 2–10 enclosed holes. With continuation the spread is 0.0% on 60×20 (identical topology from every start) and at most 0.4% on 90×30. On 90×30 the uniform start, which the 99-line code uses, is worse than 25–28 of 30 random starts at fixed penalty. Stylised: 2D, dimensionless, 150 iterations (not run to convergence), one problem, two meshes.

A figure from its own output

Paper, code and results

• README and method
• Experiments and results
• Code
• Tests

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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.