Affiliations: Mechanical Engineering Department, College of
Engineering, International Islamic University Malaysia (IIUM), Malaysia | Mechanical Engineering Department, Virginia Tech,
Blacksburg, VA, USA
Abstract: The work aims to study the root mean square (RMS) responses to
acceleration input for four state variables: the m_{s}
vertical acceleration, the m_{s} pitch angular acceleration
and the front and rear deflections of the suspensions. A half-car two
degree-of-freedom model of semi-active control scheme is analyzed and compared
with the conventional passive suspension system. Frequency response of the
transfer function for the heave, pitch of the sprung mass and suspension
deflections are initially compared and then mean square analysis is utilized to
see the effect of semi-active scheme. Results indicate that significant
improvements were achieved in the sprung mass heave and pitch responses using
semi-active control scheme. However results for the rear and front suspension
deflection show that there are limiting values of damping coefficient beyond
which, the semi-active scheme becomes disadvantageous than the passive system.
