Numerical analysis using state space method for vibration control of car seat by employing passive and semi active dampers

Abstract

In passenger cars the vibrations developed at the ground are transmitted to the passengers through seats. Due to vibrations discomfort is experienced by the passengers. Dampers are being successfully utilized to reduce the vibrations in civil engineering structures. Few dampers are used in passenger cars as well. In the present study viscous dampers and semi-active variable friction dampers are used in passenger cars. The car and car seat are modeled together as two degrees of freedom system. The study is carried out for two cases namely car moving on sagged bridges and car moving on road humps. The paper also presents the comparison of performance of both the dampers for the two cases. State space method has been employed for the numerical analysis of the study. It is found that the amplitude of displacements is reduced considerably by the employment of dampers and resonance is avoided. Performance wise viscous damper is found to be slightly better than semi-active variable friction damper.

Keywords: Car seat, viscous damper, semi-active variable friction damper, two degrees of freedom, state space method