Data-driven multifidelity and multiscale topology optimization based on phasor-based evolutionary de-homogenization
Shuzhi Xu, Yifan Guo, Hiroki Kawabe, Kentaro Yaji
TL;DR
This work tackles the computational burden and manufacturability challenges of multiscale topology optimization by introducing an evolutionary de-homogenization framework that couples MultiFidelity Topology Design with phasor-based de-homogenization. By compressing low-fidelity design variables with PCA, decoding them through a phasor-based mapping to high-fidelity geometries, and optimizing in a latent space via NSGA-II and VAE-enabled crossover (with mutation realized through image-based deformation), the approach achieves efficient, gradient-free design exploration. Numerical studies on double-clamp and L-bracket beams, as well as multi-load scenarios, demonstrate improved stiffness, buckling resistance, and stress distribution, with favorable trade-offs and robustness compared with SIMP and rank-2 lattice baselines. The framework shows practical potential for fast, fabrication-aware multiscale designs, while highlighting avenues for extending to 3D, experimental validation, and further generative-model enhancements.
Abstract
Multiscale topology optimization is crucial for designing porous infill structures with high stiffness-to-weight ratios and excellent energy absorption. Although gradient-based methods provide a rigorous framework, they are computationally expensive and struggle to capture cross-scale sensitivities in nonlinear settings. Moreover, the resulting hierarchical geometries are often overly complex and lack macroscopically meaningful features. To overcome these issues, we propose an evolutionary de-homogenization framework that couples MultiFidelity Topology Design (MFTD) with a phasor-based de-homogenization technique. The framework translates low-dimensional geometric descriptors into manufacturable high-resolution structures through a hybrid evolutionary algorithm integrating NSGA-II selection, VAE-enabled latent space crossover, and a novel image deformation-based mutation operator. This gradient-free approach achieves efficient optimization while ensuring geometric continuity. Numerical results confirm that the method effectively balances efficiency and design flexibility, offering a scalable pathway for fabrication-aware multiscale structural optimization.
