Bifurcation and chaos in multi-degree-of-freedom nonlinear vibration isolation system

The classical nonlinear behaviors and global bifurcation of a multi-degree-of-freedom nonlinear vibration isolation system subject to harmonic excitation were investigated. Based on a simplified four-degree-of-freedom model, global bifurcation analyses with the variation of excitation amplitude and frequency were carried out respectively and some bifurcation diagrams were presented. Multiple solution branches were illustrated revealing that several different types of stable motions may coexist in certain parameter regimes. Three routes to chaos, including period-doubling route, quasi-period route and crisis route, were observed successively with the increase of excitation amplitude.