Topology optimization for crashworthiness of frame structures

The present work deals with topology design of 2D-frames with respect to crashworthiness. The objective of the optimization is to control the energy dissipation history of a structure during a crash and thereby minimizing the injuries of the passenger. For this purpose several objectives and constraints are suggested and tested numerically. The ground structure for the optimization consists of rectangular 2D-beam elements with plastic hinges where the height of each beam is a design variable. The elements can undergo large rotations, so the analysis accommodates geometric nonlinearities. Concentrated masses are applied to the structure. The time integration is done by the original Newmark method combined with an implicit backward Euler algorithm. The analytical sensitivities are computed by the direct differentiation method.