Simulation Study On The Influence Of Suspension System To The Roll Stability Of Multi-axle Vehicle

The mainly purpose of this paper is a research on how the suspension systeminfluences on the roll stability of multi-axle vehicle. The non-independent suspensionsystem with air spring, which is commonly used in multi-axle vehicle, is establishedby ADAMS/Car. In addition, the leaf spring non-independent suspension model, thesteering system model, the rigid body model, the powertrain model and tire model arealso established. And then a whole truck dynamic model, referred to a van truck withthree axles, is established based on the models. Finally, we discuss how the structureparameters of the non-independent suspension used in the multi-axle vehicle influenceon the vehicle roll stability through the virtual fishhook test and the orthogonal test.In this paper, first of all, we briefly analyze the research status of the roll stabilityand the development status of suspension system of multi-axle vehicle, andsummarize the test methods and evaluation indexes which are commonly used toresearch the roll stability of vehicle.Secondly, after analyzing the characteristics of the non-independent suspensionwith air spring, we establish the non-independent suspension template and othersystem assembly template in the template interface of ADAMS/Car, and then a wholetruck dynamic model, referred to a van truck with three axles, is established instandard interface.Finally, the non-independent suspension model with air spring and the wholetruck dynamic model are respectively simulated on virtual suspension test bench andthe full vehicle virtual rig in the standard interface. And then analyze the structureparameters of the non-independent suspension which contain the length of the trailingarm, the angle between the trailing arm and the direction of the vehicle, the distancebetween the trailing arm and the wheel center, the distance between the air spring andthe wheel center, influence on the roll center height, roll angle stiffness and the rollstability of the vehicle. When analyzing the roll stability of the whole vehicle withFishHook test, the vehicle speed, the maximum angle and the angular velocity of the steering wheel are given, meanwhile, lateral-load transfer ratio in the second turningwith a large steering angle is used as the index for the roll stability of the vehicle. Inthe study of the four structure parameters influence on the full vehicle roll stability,the variation of the lateral-load transfer ratio is analyzed when the four structureparameters of the middle axle and the third axle are varying synchronization andreverse. And the impact of the four structure parameters is studied by orthogonalexperiment. Through the comparison analysis, the study conclude that the reasonableroll angle stiffness matching between the middle and the third axle suspension canimprove the roll stability of vehicle.Above all, the reasonable arrangement of non-independent suspension structureand the roll angle stiffness matching between the axle suspensions can improve theroll stability of vehicle.