Nonlinear dynamic characteristics of a micro-rotor system with rub-impact in MEMS

In this paper, a general model of a Jeffcott rotor system with rub-impact for power MEMS is established and is analyzed by the modern nonlinear dynamics and bifurcation theories. An investigation is carried out on the stability of the rub solutions and the results provide a better understanding of the dynamical characteristics of the rotor system with rub-impact under different system parameters. Nonlinear behaviors of rub-related vibrations from imbalance are studied with numerical simulations and experiments. It is demonstrated that the system alternates among the periodic, quasi-periodic and chaotic motions as the system parameters change. The dynamical characteristics can be effectively used to diagnose the rub-impact fault for rotating micro-machineries.