Periodic response analysis of a Jeffcott-rotor system under modified saturation-based control.

In this paper, two modified nonlinear saturation-based controllers and negative velocity feedback controllers are integrated to suppress the horizontal and vertical vibrations of a horizontally supported Jeffcott-rotor system at primary resonance excitation and the presence of 1:1 and 1:2 internal resonances. The second order approximations and the amplitude equations are obtained by applying the integral equation method to analyze the nonlinear behavior of this model. The stability of the steady-state solutions is determined based on the Floquet theory. The necessity of adding a negative velocity feedback to the main system is stated. The effects of different control parameters on the frequency-response curves and the force-response curves are investigated. Time histories of the whole system are included to show the response with and without control. It is shown that the main systems steady-state amplitude under the proposed control is reduced by about 99.8% and the negative velocity feedback can suppress the transient vibrations and prevent the main system having the large amplitude vibration. Finally, numerical simulations are provided to verify the effectiveness of the integral equation method. • Two modified saturation controllers are used for Jeffcott-rotor system. • A integral equation method is used for a four-degree-of-freedom system. • Analytical solutions based on our method agree with numerical simulations. • The saturation controller can avoid the phenomenon of double peaks. • The negative velocity feedback can suppress the transient vibrations. [ABSTRACT FROM AUTHOR]