挠性卫星在轨非约束模态计算研究

Research on Calculation of On-Orbit Unconstrained Modal of Flexible Satellite

给出了一种适合工程应用的挠性卫星在轨模态计算分析方法:先通过地面试验对有限元模型进行校核,求出挠性附件约束模态结果,再结合整星动力学将约束模态转换成非约束模态结果。实例计算结果表明该方法能够准确计算挠性卫星在轨模态。工程中卫星在轨模态频率计算误差可在15%以内。

A method of on-orbit modal calculation suitable for the engineering application is presented in this article. Firstly, the finite element model should be corrected through the ground test, and the constraint modal results of flexible appendages will be extracted. Combining with the dynamics equation of entire satellite, the constraint modal will be translated into unconstraint modal by using the eigenvalue method. The example shows that the method in this article can calculate the on-orbit modal frequency accurately. In engineering, the error of on-orbit frequency will be under 15%.