Reliability-based topology optimization based on bidirectional evolutionary structural optimization using multi-objective sensitivity numbers

Reliability-based topology optimization (RBTO) is used to obtain an optimal topology satisfying given constraints, as well as to consider uncertainties in design variables. In this study, RBTO was applied to obtain an optimal topology for the inner reinforcement of a vehicle’s hood based on bidirectional evolutionary structural optimization (BESO). A multi-objective topology optimization technique was implemented to obtain the optimal topology for two models with different curvatures while simultaneously considering the static stiffness of bending, torsion, and natural frequency. A performance measure approach (PMA) with probabilistic constraints formulated in terms of the reliability index was employed to evaluate the probabilistic constraints. The optimal topology obtained by RBTO was evaluated and compared to that obtained by deterministic topology optimization (DTO). A more suitable topology was obtained through RBTO than DTO even though the final volume obtained by RBTO was generally slightly greater than that obtained by DTO. The multiobjective optimization technique based on BESO can be applied very effectively with topology optimization for a vehicle’s hood reinforcement.