Impact of joint on car body stiffness at concept design stage

The impact of joints on car body stiffness was considered in order to forecast the performance of car body structure more accurately in the car body concept design stage. The five main joints were simulated by torsion spring element and rigid elements in concept car body model. Vector direction and stiffness of torsion spring were obtained by solution of stiffness equations of detailed joint model. Each kind of joint was applied for the concept car body model respectively and the impact of each joint on bending stiffness and torsion stiffness were calculated. The impacting factor was introduced in order to compare the impact of different joint on stiffness of car body. At last, the two cases were simulated and the result showed that design precision of car body structure was improved due to consideration of concept joints.