Theoretical Study of Semi-Active Suspensions By Nonlinear Feedback Control

Active Control Technology (ACT) has been applied to the improvement of dynamics of ground vehicles, such as ride quality, running stability and handling performances of automobiles. In this paper, the two degrees-of-freedom (two-DOF) model of automobiles with a semi-active suspension is analyzed theoretically using computer simulation. A nonlinear feedback control system by which the coefficient of the damper force is continuously modulated is proposed and analyzed to discuss the vibration suppression characteristics when the vehicle is excited by a random road surface.