The Improvement And Optimization Of Chassis In The Motor Vehicle Of Category N2on Account Of Steering Stability

Since its appearance on the market three years ago, a certain style of A00-Classpassenger car has been well received by purchasers with a sales volume of nearly tenthousand per month, owing to its low fuel consumption, inexpensive price andconvenience in maintenance. However， in the recent several months， the sales of thisstyle of car has been declining. According to the market feedback and the follow-upsurvey on clients， apart from its old-fashioned appearance, the poor performance of itschassis prevents customers from choosing it. Therefore, in order to enhance itscompetitiveness in the market， the improvement and optimization of its chassis ishighly necessary to obtain an excellent steering stability, improve customers’ drivingexperience and regain market recognition.The first approach for the improvement and optimization of its chassis is to find theexisting problems of this style of car. To begin with, experiments on the tyremechanical characteristic and the suspension K&C characteristic, subjective assessmentand objective tests are conducted to offer clues for the finding of weaknesses in itschassis. After that, a chassis model is established with the assistance of ADAMS.Finally, drawbacks which need immediate attention are affirmed based on experimentalconclusions and the real situation of this style of car， and according performancemodification plans for hard points and components of the chassis are provided. Afterbeing tested and verified by the ADAMS model, ultimate improvement andoptimization goals are proposed. By means of a new round of subjective and objectiveassessments and the K&C characteristic test, the plan’s feasibility is confirmed.Eventually, the car’s steering stability is significantly improved after its chassis beingadjusted and calibrated.In this thesis，substantial and exhaustive experiments，which are enforced on theearlier stage of the chassis’ adjustment and calibration, and an advanced K&C testbedfor the finished automobile， which is introduced as experimental tools for the proposalof improvement and optimization goals, greatly enhance the accuracy of the test for thechassis’ actual performance; in the subjective assessment, detailed assessment items areestablished to precisely demonstrate the driver’s driving experience, which contributesto finding the defects of this style of car in an intuitional way. On the premise that realvehicle testing is unavailable， the ADAMS model, which can not only verify thevalidity of tests on the earlier stage but also stimulate the improved project on the latterstage, can make an accurate judgment on the performance of the improved chassis. As a result, a mass of time and economic cost in implementing real vehicle testings aresaved.