柔性航天器自由飞行状态系统基频的估算方法

The natural frequency calculating for flexible spacecraft in free flight

首先分别采用部件模态和系统模态建立柔性航天器在轨运行状态下的动力学方程;重点推导了航天器系统模态与其部件模态之间的模态恒等式,得到了由部件模态计算系统模态频率的一般公式;然后结合目前航天器的常见构型,对一般公式进行合理简化,得到了估算航天器系统基频的简化公式;最后给出了简化公式的工程应用算例。

The calculation of the natural frequencies of flexible spacecraft was studied.First,the dynamical model of flexible spacecraft was formulated using appendage modes and system modes respectively.Second,the modal identity between appendage modes and system modes was deduced by which the natural frequencies of flexible spacecraft can be calculated.Finally,Considering the normal framework of modern spacecraft,the identity was simplified and the estimating formula for its basic natural frequency was got.The formula is simple and practical,and it shows the contribution of each appendage to the basic frequency of flexible spacecraft.