Abstract: As the body structure is supposed to guarantee its static and dynamic bearing capacities, so it is very importance to determine the optimal topological body structure to consider a variety of loading case and the requirement of dynamic performance in the conceptual design phase. Combining analysis of multi-body dynamics with multiple loading conditions, a comprehensive objective function maximizing the static stiffness under multi-conditions and dynamic frequency of vibration is defined using the compromise programming approach, and comprehensive objective topology optimization is conducted. Meanwhile, the analytical hierarchy process(AHP) method is applied to obtain the weights of the body stiffness in various load conditions. The instance of the topology optimization results of a formula racing car body structure shows that this method is feasible and effective when it is applied to determine an advanced conceptual body structure. Moreover, the contrastive study is carried out to compare the comprehensive objective optimization approach proposed in this study to those that determine the weight ratio empirically or by orthogonal experiment. The study result shows that the body structure stiffness and the first six frequencies are increased and the structure is more reasonable, while the computational efficiency is improved.

Key words: body structure, comprehensive objective, dynamic performance, topology optimization, weight ratio