Study of the active suspensions impact in compact/sportive vehicles performance

Abstract

This research compared the characteristics of a full vehicle model, representing a Mustang 2003 using passive, semiactive and active suspension systems. For this, ADAMS/Car simulation software was used. The passive model was separated in four models, with and without antiroll bars; the semiactive models include Skyhook logic which varies the coefficient of viscous damping to simulated the semiactive suspension; the active model have forces in each damper to simulated the actuators and the controller was simulate with the ADAMS/Control tools kit. In first instant the research was based on discovering stabilizer bars influences in the vehicle's behavior, after that the active and semiactive suspension systems was included in the analysis. Some characteristics of the vehicle model response were analyzed, including the pitch and roll displacement and chassis acceleration of the vehicle body. The vertical displacement and acceleration of the body mass were used to represent the ride comfort of the vehicle, while the roll displacement of the body and the lateral velocities of the body were used to evaluate the vehicle safety. The results of the study show that the antiroll bars help some of the vehicles characteristics but nevertheless when helping one of them it harms others having mixed them to reach an intermediate behavior. The active and semiactive suspension improve the vehicle behavior in similar way, the results for this kind of suspension have similar performance, since both systems feedback the relative velocity of the body to control the dynamic responses. Both models have better performance, having better handling and greater comfort that the passives systems. The velocity in turns was increased by the active and semiactive suspensions systems having better safety. Chassis accelerations are smooth in the active and semiactive suspension systems having better comfort.