Estudo de suspensões passiva, semi-ativa MR e ativa

Abstract

The present work it’s divided in three principal part’s:  Study of theory approaching the concepts and features on vehicular suspensions and its components, on ride comfort related to the vehicles and humans, and on fluids magneto-rheologicals.  The development of the model, where the mathematical methods of modeling of systems, the procedures used in the obtainment of model, hypothesis, simplifications, elements used and control systems are described. Three types of mathematical models are discussed, being that all are linear. One more simple with 1 degree-of-freedom (DOF), obtained easily in literature review, other of a ½ vehicle with 2 DOF, made up by chassis movements, and last one model of 4 DOF, than takes into account both rear and front axles connected to chassis of vehicle. The control system is then equating, and representation and simulation their occur through the presents tools in software Matlab©.  Simulations and Results Analysis. On this part are accomplished the simulations of equating of the passive, semi-active and active suspensions systems into of environment SIMULINK® of Matlab©. The numeric simulation is used for forecast of the performance on suspensions systems when the vehicle is submitted to the entered one or know movements, attained the vibrations responses at time and frequency domain. With the results of the simulations, it is argued the relative performance to the ride comfort of the passengers, the security, the stability and the xii viability of the passive, semi-active MR (magneto-rheological) and active suspensions systems, comparing the results of the simulation with values of other studies. Is concluded that the numerical model contribute for a success of control, and that the semi-active MR suspension system is a little less efficient mode, but enough effective, and more viable that the active suspension, in vibration control in ride vehicles.