Dynamic design of a nonlinear energy sink with NiTiNOL-steel wire ropes based on nonlinear output frequency response functions

A novel vibration isolation device called the nonlinear energy sink (NES) with NiTiNOL-steel wire ropes (NiTi-ST) is applied to a whole-spacecraft system. The NiTi-ST is used to describe the damping of the NES, which is coupled with the modified Bouc-Wen model of hysteresis. The NES with NiTi-ST vibration reduction principle uses the irreversibility of targeted energy transfer (TET) to concentrate the energy locally on the nonlinear oscillator, and then dissipates it through damping in the NES with NiTi-ST. The generalized vibration transmissibility, obtained by the root mean square treatment of the harmonic response of the nonlinear output frequency response functions (NOFRFs), is first used as the evaluation index to analyze the whole-spacecraft system in the future. An optimization analysis of the impact of system responses is performed using different parameters of NES with NiTi-ST based on the transmissibility of NOFRFs. Finally, the effects of vibration suppression by varying the parameters of NiTi-ST are analyzed from the perspective of energy absorption. The results indicate that NES with NiTi-ST can reduce excessive vibration of the whole-spacecraft system, without changing its natural frequency. Moreover, the NES with NiTi-ST can be directly used in practical engineering applications.