Computation of stabilizing PI parameters for vehicle suspension system using the stability boundary locus

This paper presents a new approach for the design of vehicle suspension system with the goal to maximise passenger comfort by minimising vertical acceleration. For this reason PI controlled suspension system, at which controller parameters are computed by using the stability boundary locus, is proposed. In order to select the best parameters in the stability region obtained using the stability boundary locus, the phase margin and the gain margin of system is studied and step response of the system is evaluated. The proposed method offers several important advantages over existing results since it is simple to apply and does not need to sweep over the parameters.