Crashworthiness design of periodic cellular structures using topology optimization

Periodic cellular structures are widely used in structural protection due to their lightweight and excellent energy absorption characteristics, but the corresponding crashworthy design is still limited. Based on the framework of hybrid cellular automata (HCA), the optimal design of periodic cellular structure for crashworthiness is carried out. To guarantee the periodicity of cellular structure, elemental internal energy (EIE) is redistributed averagely as a periodic constraint. Then, by iteratively modifying the local EIE target, the cellular structure is optimized until the maximum energy absorption (EA) is obtained under the specific volume fraction constraint. Through several 2D and 3D numerical examples, this design method is proved to be efficient for the crashworthiness design of periodic cellular structures. Specifically, EA of the optimized cellular structures in this study can be improved by design comparing with solid structures and classical honeycombs. Effects of cellular number and volume gradient on crashworthiness are also discussed.