Fatigue Damage Analysis Of Suspension Structural Components Based On Virtual Pavement

Suspension is an important bridge between the body and the road.The fatigue durability of the structural components can be related to the user’s experience and personal safety.Fatigue durability can be one of the most important performances in automotive construction,and its development cycle is long.The R&D model based entirely on design-test-modification will greatly increase the cost of vehicle R&D and is not conducive to fierce market competition.How to accurately predict the fatigue damage of suspension structural components in the early stage of automobile development has become the focus of current research.In this paper,the suspension control arm and torsion beam are studied.The CAE technology is used to predict and analyze the fatigue damage of the two,and a set of improved and reliable design methods for the fatigue damage of the suspension structure based on the full simulation environment is summarized.In the fatigue damage analysis process summarized in this paper,firstly,threedimensional model and finite element model of control arm and torsion beam are established by using CATIA software and Hyper Mesh software respectively.Material properties were assigned to it,unit quality was checked and modal analysis was performed.Using the CDTire PI software for tire parameter identification,the CDTire3 D high frequency tire model was obtained.The multi-body dynamics model of the whole vehicle was built by Motion View software,and the control arm and torsion beam were flexibly processed.The KC virtual test bench and the four-column virtual test bed were built separately to verify the vehicle model for rationality and accuracy.Then,according to the test site to enhance the characteristics of durable road roughness,Matlab software is used to establish various types of enhanced durable virtual pavement models.The kinematics simulation of the vehicle at different speeds is carried out,and the time domain load spectrum at the critical connection point of the control arm and the torsion beam is extracted.In order to ensure that the control arm and the torsion beam do not suffer from strength damage,the maximum stress under each road condition is checked.Finally,using n Code Designlife software,the stress-life curve of the material is given to the control arm and the torsion beam,and the fatigue damage analysis workflow is built.The fatigue damage analysis of the control arm and the torsion beam under different road load spectrums was carried out,and the dangerous points with the largest fatigue damage value were counted.An improvement scheme was proposed for the area where fatigue damage may occur,and the simulation verification was carried out.According to the fatigue damage prediction analysis process of this paper,the fatigue damage prediction analysis of the suspension structure can be carried out before the prototype test,and whether the fatigue life meets the design requirements.The analysis results show that the method has strong feasibility and practical engineering significance.