Pre-Validation Method of Steering System by Using Hybrid Simulation

In this study, the preliminary validation method of the steering system is constructed and the objective is to satisfy the target performance in the conceptual design stage for minimizing the problems after the detailed design.

The first consideration about steering system is how to extract the reliable steering effort for parking. The tire model commonly used in MBD(Multi-Body Dynamics) has limited ability to represent deformations under heavy loads. Therefore, it is necessary to study adequate tire model to simulate the behavior due to the large deformation and friction between the ground and the tire. The two approaches related with F tire model and mathematical model are used. The second is how to extract each link’s load in the conceptual design stage. Until now, each link’s load could be derived only by actual vehicle test, and a durability analysis was performed using only pre-settled RIG test conditions. Therefore, in this study, we established the process of deriving the RIG test conditions by integrating the hydraulic system and the dynamics model without actual vehicle test. The last one is how to apply the flexibility of structure to MBD. In this study, a tool is constructed to automatically reflect the beam’s property by making discrete beam model. As a result, it can be used to set the vehicle’s hard points which minimize the influence between steering system and suspension system on the excessive payload or other events.

Through the whole process, we are able to find optimal result by applying the ATC(analysis target cascading) to the steering system concept of the medium truck FMC(Full Model Change).