LATERAL STABILITY AND HANDLING BEHAVIOUR OF A CAR

Abstract

The lateral stability and handling characteristics is always an important aspect of vehicle behaviour. The behaviour of vehicle during turning can only be predicted by lateral stability investigations. In this dissertation, work a 3-4egree of freedom mathematical model of a car has been taken up for investigating the lateral dynamic behaviour. The equations of motion are developed by using the Newton's second law of motion and these motion equations are used for evaluating the eigen values. The handling behaviour of vehicle is analysed by the understeer coefficient. The value of understeer coefficient is presented in the tabular form in the speed range of 5-35 m/sec. The force and moment characteristics of tyre affect the vehicle stability and handling behaviour. In the present work the force and moment characteristics of tyre are modelled with the help of the Magic Formula and then the tyre model is simulated with the vehicle model for investigating the stability and handling behaviour of car. Eigen values of various modes of vehicle motions are evaluated by means of a program. and the modes of motions studied. The results are presented making various parametric studies, recommendations are made and conclusion drawn for improving stability and handling behaviour.