The Study On K&C Characteristics Of SUV Suspension System

K&C characteristics of suspension system are the crucial bridge which has been usedfor connecting suspension structure design and vehicle performance matching. They areplaying a critical role in vehicle performance as well.The present thesis has relied on a SUV platform which was conducted by a motorcorporation to explore detailed analysis about K&C characteristics of suspension system.The thesis analysis mainly focused on the following research questions:(1) To study about the basic theories of K&C characteristics of suspension system andto point out the key parameters on evaluating K&C characteristics of suspension system. Thethesis has made qualitative analysis about the impact of K&C characteristics to vehicleperformance which has laid foundation of the following suspension system modeling andmodel validation.(2) To simplify and abstract the suspension system topological structure ofbenchmarking vehicle according to the architectural features of suspension system from aSUV platform; to get the parameters of hard point coordinates, damping element and theflexible features of elastic element through measurement, then to construct simulation modelwith the modeling software.(3) Based on the simulation model, the present thesis has conducted kinematicssimulation experiment analysis on parallel round condition and rolling condition and it getsthe variation characteristics of such parameters as wheel toe angle, camber angle, the wheellateral displacement, the wheel deformability, motion roll center height, king pin camberangle, kingpin caster angle, king pin extraversion drag, caster drag, body roll angle, wheeltrack and the like;On the other hand, the thesis has conducted kinematics simulation experiment analysisabout synthetic transverse force of flexible working conditions, reverse horizontal force offlexible working conditions, vertical force condition, direct back to positive momentconditions and reverse back to the positive moment conditions and gets the changing rate of toe-in and camber; It has compared the parameters with the actual measured value. Thecomparison has shown that the kinematics features of suspension has higher simulationprecision, however, the simulation precision of elastic kinematics features still has someerrors.(4) According to the requirement of the content, the thesis has made preliminarydiscussion about the evaluation method about operational stability. It has promotedcomprehensive experimental method and evaluation index with the help of relevant contentabout steady state operating performance from the subjective evaluation system of GM andsome experimental projects in national standards. Furthermore, it has used the Carsim modelto make steady operational qualitative analysis of higher lateral acceleration steering,frequency response, central steering, steering wheel angle step input. After comparing thesimulation result and real vehicle test statistics, we found the effectiveness and feasibility ofthe model.The research result of the present thesis lies in its reference value in the process of modelingSUV platform K&C characteristics and the studies about the impact on operational stability.It also has certain value to the development and listing of SUV platform.