Elena Raponi, Mariusz Bujny, Markus Olhofer, Nikola Aulig, Simonetta Boria, Fabian Duddeck, "Kriging-Assisted Topology Optimization of Crash Structures", Computer Methods in Applied Mechanics and Engineering, 2019.Abstract
Over the recent decades, Topology Optimization (TO) has become an important tool in the design and analysis of mechanical structures. Although structural TO is already used in many industrial applications, it needs much more investigation in the context of vehicle crashworthiness. Indeed, crashworthiness optimization problems present strong nonlinearities and discontinuities, and gradient-based methods cannot be applied. The aim of this work is to present an in-depth analysis of the novel Kriging-Guided Level Set Method (KG-LSM) for TO, which is based on an adaptive optimization strategy with Kriging model and a modiﬁed Constrained Expected Improvement (CEI) as the update criterion. The adopted representation using Moving Morphable Components (MMCs) allows for a signiﬁcant reduction of the dimensionality of the problem and an eﬃcient use of surrogate-based optimization techniques. A cantilever beam test case of diﬀerent dimensionalities is used to validate the presented strategy, as well as identify its potential and limits. The method is then applied to a 2D crash test case, involving a cylindrical pole impact on a rectangular beam ﬁxed at both ends. Compared to the state-of-the-art Covariance Matrix Adaptation Evolution Strategy (CMA-ES), this optimization algorithm demonstrates to be eﬃcient in terms of convergence speed and performance of the optimized designs.