Resumo:
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
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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.
