Optimization study of handling stability of a car considering flexible subframe
Generally,vehicle simulation is studied under the assumption that the subframe is rigid.However,in reality,the subframe is flexible.In order to study the influence of subframe flexibility and material property change on the handling stability optimization,HYPERMESH software modal calculation was used to obtain the flexible front subframe file,and modal analysis was carried out to avoid its resonance with the engine and body.The flexible front subframe was imported into ADAMS software to re-place the original rigid front subframe,and a rigid-flexible coupling model of a car with different material properties of the flexible front subframe was established,and the K & C simulation of the suspension and the simulation of the handling stability of the whole vehicle were carried out for comparative study.The NSGA-Ⅱ algorithm was used to optimize the design of the front sub-frame bushing stiffness parameters with the optimization objective of vehicle handling stability.The results show that the elastic deformation after changing the material properties of the flexible front subframe affects the force on the suspension system,which changes the K & C characteristics of the suspension,and then changes the handling stability of the rigid-flexible coupling model of the whole vehicle.Changing the material properties also causes the results of the multi-objective optimization of the bushing stiff-ness parameters at the articulations of the front subframe with the suspension and the body to change.After the multi-objective op-timization,the yaw rate gain,the body roll angle gain,and the delay time of lateral acceleration are all reduced,and the handling stability of the whole vehicle rigid-flexible coupling model is improved.
万方数据
维普
