SEMI - ACTIVE SUSPENSION SYSTEM DESIGN FOR QUARTER CAR MODEL AND ITS ANALYSIS WITH PASSIVE SUSPENSION MODEL

The three main objectives that a suspension system of an automobile must satisfy are ride comfort, vehicle handling and suspension working space. Ride comfort is directly related to the vehicle acceleration experienced by the driver and the passengers. Lesser vertical acceleration, higher is the level of comfort. The aim of the Project was to design and analyze the semi active suspension system models using skyhook, ground hook and hybrid control for quarter car. The project work includes modeling of semi - activ e suspension system in MATLAB simulink, using 2 degree of freedom quarter car model. The skyhook on - off, ground hook and hybrid control strategies were designed using control laws stated in literatures. Simulated results have been compared with passive sys tem for time response analysis of body vertical displacement and vertical displacement of quarter car. Simulation was carried out for various road conditions such as random road excitation, road bump excitation, step input etc.