含串联非线性能量汇的整星系统吸振效果研究

Vibration absorption effect of whole satellite system with series nonlinear energy sink

为了改善卫星在发射阶段的动力学环境,通过在卫星适配器结构中引入非线性能量汇装置,将其与卫星主结构耦合,实现整星系统的振动抑制。对于耦合后的整星等效集中质量模型,考虑了非线性能量汇装置所受重力对非线性弹簧恢复力的影响,并利用四阶龙格库塔法求出整星系统在谐波激励和冲击激励下的振动响应,结果表明考虑重力情况较未考虑重力更加精确,振动响应幅值偏小。为了在不改变原整星系统固有频率的基础上进一步提升非线性能量汇装置的消振效率,采用具有二级串联结构的等质量非线性能量汇装置,并基于靶向能量传递理论对其非线性刚度参数进行优化,分析结果表明引入串联非线性能量汇结构较单级结构在冲击激励下能获得更好的减振效果。

Here, in order to improve dynamic environment of a satellite in launching stage, a nonlinear energy sink device was introduced into the satellite adapter structure, it was coupled with the main structure of the satellite to realize the whole satellite system’s vibration suppression. For the equivalent lumped mass model of the whole satellite system after coupled, considering influences of the nonlinear energy sink’s gravity on nonlinear spring restoring force, using the 4 th order Runge-Kutta method, vibration responses of the whole satellite system under harmonic excitation and impact excitation were solved. Results showed that vibration responses considering gravity are more accurate than those without considering gravity, their amplitudes are a bit smaller;to further lift the nonlinear energy sink device’s vibration suppression efficiency without changing original natural frequencies of the whole satellite system, a nonlinear energy sink device with the same mass and a two-stage series structure was adopted, and its nonlinear stiffness parameters were optimized based on the theory of target energy transfer. The analysis results showed that the nonlinear energy sink with 2-stage series structure can have better vibration reduction effect than the one with a single-stage structure can under impact excitation.