Topology Optimization for Crash

This paper is contributed to the topology optimization of structures under highly nonlinear dynamic loading, e.g. crash. We present our experiences with two software tools: LS-TaSCTM (developed by LSTC, available since 2009, the first version was named LS-OPT/TopologyTM) and Genesis-ESL ® (developed by VR&D) and highlight the possible application areas, capabilities and limitations of the implementations. LS-TaSC nonlinear topology optimization with LS-DYNA can be applied to nonlinear static and dynamic problems. The underlying method is “Hybrid Cellular Automata” (HCA) which is a heuristic, gradient-free approach. The objective is to obtain a structure with uniform internal energy density subject to a given mass fraction. The basic idea of the “Equivalent Static Load”- Method (ESL) is, to divide the original nonlinear dynamic optimization problem into an iterative “linear optimization ↔ nonlinear analysis” process with linear static multiple loading cases for the optimization. The iterative optimization ↔ analysis process is to capture the nonlinearities and the multiple loading cases reflect the nonlinear dynamic deformation progress of the structure within the optimization.