With a locking-free finite-element simulator, how much surrogate error can a design loop tolerate?
research/accel-surrogatelock
With a locking-free Q6 finite-element simulator, how much surrogate error can a design loop tolerate? At 64x8 the surrogate adds 0.5 to 0.8 points to the FE's 2.3 % error; with no safety margin a min-mass screen breaks the limit in 24 to 33 % of cases, with a 5 to 10 % margin 2 to 9 %. Stylised.
What it found
The 2D cantilever of accel-surrogate2d with a locking-free Q6 (incompatible-modes) element, which is within 0.6 % of Timoshenko theory on a 16×2 mesh where Q4 gives half the deflection. An 8-32-32-1 MLP (float, 6 and 8 bits) imitates it at three mesh sizes. At 64×8 the surrogate adds about 0.5 to 0.8 points to the FE's own 2.3 % error. In a minimum-mass search over 1,000 designs and 15 limits, a screen with no safety margin breaks the limit in 24 to 33 % of cases (FE alone 6.7 %); a 5 to 10 % margin cuts this to 2 to 9 % for about 0.5 to 1.6 % extra mass. Stylised, random-pool screen, 3 seeds, modelled energy.
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.