Nonlinear dynamics of magnetorheological whole-satellite with variable parameters under small amplitude and medium-high frequency vibration

Abstract

Abstract Whole-satellite vibration isolation system with magneto-rheological (MR) damper is a new idea to solve the problem of small amplitude and medium-high frequency vibration. However, it also brings challenges to MR technology, wherein the super hysteresis and variable stiffness properties of MR damper are lack of research. Considering the particularity of MR damper under small amplitude and medium-high frequency conditions, the MR damper is identified by employing an improved Bingham model, then dynamic characteristics of the whole-satellite system are analyzed by nonlinear bifurcation theory, and then the nonlinear analysis method of MR whole-satellite system with variable parameters is proposed. To verify the effectiveness of the nonlinear analysis method of MR whole-satellite system with variable parameters, the influence of bifurcation parameters on the system parameters is analyzed qualitatively and quantitatively, then time histories and phase diagrams of fixed-parameter and parameter-varying MR whole-satellite system are compared. The analysis suggests that the improved Bingham model adequately characterizes the strong nonlinear hysteretic and variable stiffness behavior of the MR damper. Moreover, the comparison results illustrate that the time histories and phase portraits of the parameter-varying system are in good agreement with those of different fixed-parameter system, and the parameter-varying system has good adaptability in the selected range of bifurcation parameters. This study provides a basis for the design of structural parameters and the optimization of control strategy for MR whole-satellite system.