Stress-constrained topology optimization of lattice-like structures using component-wise reduced order models

Lattice-like structures can provide a combination of high stiffness with light weight that is useful in many applications, but a resolved finite element mesh of such structures results in a computationally expensive discretization. This computational expense may be particularly burdensome in many-query applications, such as optimization. We develop a stress-constrained topology optimization method for lattice-like structures that uses component-wise reduced order models as a cheap surrogate, providing accurate computation of stress fields while greatly reducing run time relative to a full order model. We demonstrate the ability of our method to produce large reductions in mass while respecting a constraint on the maximum stress in a pair of test problems. The ROM methodology provides a speedup of about 150x in forward solves compared to full order static condensation and provides a relative error of less than 5% in the relaxed stress.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

Lattice-like structures often have high stiffness and light weight, but the computational cost of resolving the finite element mesh can be expensive. To address this issue, we propose a stress-constrained topology optimization method that utilizes reduced order models as a cost-effective surrogate, providing accurate computation of stress fields while significantly reducing run time.