Behavior of a semi-active suspension system versus a passive suspension system on an uneven road surface

Abstract

The present paper intends to study the behavior of semi-active suspension systems in comparison with passive suspension systems when subjected to oscillation sources caused by the rolling surface. For this, it was necessary to establish the equations specific to the passive and semi-active suspension systems. For each case, the simulation schemes were developed using Matlab Simulink. For the simulation, the quarter car model was chosen. In order to verify the correctness of the model, the State Space and Transfer function models were also used. As the passive dampers have a linear dampening characteristic, we studied the semi-active systems that use magneto-rheological dampers with adjustable characteristics. In the simulation diagram we used a PID controller-proportional integrative derivative. Using two types of stimulus signals we analyzed the behavior of the semi-active suspension system with different dampening coefficients. By simulation, response signals for damper/spring displacement and damper/spring velocity were obtained. The analysis of the obtained results shows the advantages of semi-active systems in comparison with passive systems and the limitations of such systems compared to active systems.