On the chaotic response of a nonlinear rolling isolation system

Isolation systems protect fragile objects from potentially-damaging shocks and shakes by mechanically decoupling motions of the object from motions of the surrounding environment. Shock and vibration isolation systems have been applied to systems ranging from the micron scale to the scale of entire buildings. Many isolation systems operate within a linear range, while others have strong nonlinearities. The focus of this paper is on the chaotic response of a rolling-pendulum vibration isolation system. An experimentally-calibrated model is reduced to a single-degree-of-freedom nonlinear system. The nonlinearities involve softening behavior at intermediate responses and stiff impacts at large amplitudes. This model is investigated numerically to explore and establish the influence of harmonic forcing parameters on the chaotic nature of responses. Rich chaotic behavior is exhibited in the case where the response includes impacts.