Modelagem, simulação e análise de desempenho do controle fuzzy para uma suspensão veicular ativa

Abstract

Vehicle suspension systems are essential to ensure the comfort of a vehicle’s passengers. This paper consists in the study of the three main types of vehicular suspension: passive, semi-active and active; as well as the comparison of the active suspension’s performance over the traditional passive suspension. The current regulations classify vehicle comfort based on the effective value of the vertical acceleration transferred from the suspension system to the vehicle body. The active suspension is characterized by the presence of a control system that applies an active force to the vehicle suspension in order to minimize the effects of such acceleration. Through numerical simulation, both suspension systems are simulated in order to obtain their behavior against a disturbance of soil. The control strategy used in the simulation of the active suspension was the fuzzy logic control; a nebulous logic that can be programmed to make decisions similar to human reasoning. The active suspension system demonstrated a significantly greater rms acceleration value than passive suspension. However, it has proved much more effective in attenuating the consequences of such an acceleration in passenger’s sensation of comfort, as can be seen in relation to the displacement of the body. Thus, it is clear that the parameter of comfort evaluation only through the vertical acceleration analysis established in the current regulations does not apply to all types of suspension, especially to the active suspension properly designed with the fuzzy control.