Optimal Design Of Front Suspention And Steering Systems Based On Tire Wear Model

With the development of economy and society in china, the electronic vehicles，with the advantages of zero’s emission and lower noise， have been widely used in thetourism attractions, school campus, and districts. The electronic car has some featuresthat low speed, good road condition and big load change. On this condition, it’s moreimportant to pay attention to the tires wear than others. In order to get low tire wear,lots of work should be done in designing the suspension system and steering system.As increasing in the accuracy of matching the front wheel alignment parameters,declining in the ackerman-error, which based on the reasonably designing of thesuspension and steering system, the tire wear will decreases, and themarket-competitions will be improved.Firstly, the theories of tire wear are introducted briefly. Analyzing the mechanismof tire wear in the condition of steady state tire cornering model, steady statelongitudinal-slip model and steady state tire cornering&longitudinal-slip model, allof these models are under base of brush model. A calculation method of tire frictionpower is build, and the relation is found beween the tire slip angle and the tire firctionpower. To quantize the effects on the tire wear which result from changing the frontwheel alignment parameters and the ackerman error, and analyze the mathematicrelationship between them and slip angle. A matching relationship is found betweenthe toe angle and the camber on the basis of analyzing tires lateral slippageAnd then, a preliminary design method about suspention and steering systems isintroduce and used to get the first scheme of hardpoint. According to the layout of car,a multibody dynamics model is built in ADAMS. Base the model，analyze is doneabout the front wheel alignment during the wheel rebound and bound and theacekerman error in the steering situation.In addition, it calculates the sensitivities of hard point about the toe angle, thecamber and the ackerman error in the condition of steering condition and boundcondition. By using the RSM method, some RSM functions are fitted to the toe angle,camber, and the ackerman error with factors after analyzing the suitable sensitivevariable parameters.Finally, according to the mechanism of tire wear, the front wheel alignmentparameters is optimized by limiting the scope of the trend of wheel alignmentchanging and the initial values and making all the aims more suitable. After these, the optimized hardpoints are tested and verifed the in ADAMS modle. It was proved agreat decline in the tire wear.To some extent, it also improve the vehicle handlingstability...