An investigation on the Resonances and Chaotic Behavior of a Nonlinear Vehicle Suspension System

علوم کاربردی و محاسباتی در مکانیک

Article 4, Volume 24, Issue 1, June 2012, Pages 53-70   

Document Type: Original Article

DOI: 10.22067/fum-mech.v24i1.21492

Authors

m. Rezaee^* ; H. Samandari

Abstract

In recent years, more attention has been paid on intelligent vehicle suspension systems equipped with magneto-rheological dampers. In order to investigate nonlinear vehicle dynamics, in the majority of the researches, a quarter-car model with one or two degrees of freedom is used. In such simple models, one can only study the bounce motion of sprung and unsprung masses. In this paper, in order to consider more realistic model for vehicle suspension system, a nonlinear half car model with four degrees of freedom is employed. Frequency response diagrams of the model have been obtained. In order to identify the region of excitation frequency in which the system has chaotic behavior, the bifurcation and Poincare maps are used. Results show that near the heave and pitch natural frequencies, the system forced response has been changed considerably and new unstable region has been appeared in frequency diagrams. Moreover, results show that in comparison with quarter car model, the resonant frequency of pitch motion intensifies the chaotic response.

Keywords

Half-car model؛ suspension system؛ Non-linear vibration؛ Chaos; Bifurcation

References