VEHICLE SUSPENSION CONTROL SYSTEM USING FULL CAR MODEL.pdf

Abstract

This study covers the complete control problem for the automotive industry. Based on the knowledge of vehicle suspension system its complete mathematical model is first established. The model utilizes 8 degrees of freedom so that complete analysis of the suspension and its effect on the vehicle could be understood. Once it is done, a proper control scheme is designed to find the solution for the problem that we encounter in case of passive suspension system. In regular passive suspension system, the main problems that one encounters is the fixed parameters for the elements that are used in suspension system. These parameters are stiffness and damping coefficients for the spring and damper. So when vehicle suspension system is first manufactured these parameters are designed for certain road profile, but in practical scenario there is variable road profile, so those passive suspension systems would not work under every condition. So one needs to develop a control scheme for the complete control of suspension system. In this study two different control variants are discussed. One is active control scheme based on PD and optimal control theory (LQR) and the second one is semi active control scheme based on dedicated control scheme for suspension system. Both strategies are designed for full car model. For active control some sort of actuators are used while in case of variable damping approach is used. At the end these control techniques are examined in detail for both cases and analysis is done based on the results. There is a clear indication of the fact that controlled suspension system has a better response as compared to uncontrolled suspension system