多柔体系统动力学模型的特征值降阶方法

详细研究了多柔体系统动力学模型的特征值降阶问题，针对挠性空间飞行器系统的姿态动力学方程，推导出基于Riccati迭代算法的特征值模态截断准则和计算步骤。分析结果表明，它较一般特征值截断准则更能精确地反映原系统特性，并且能准确地保留原系统低阶模态频率和振型。其模态截断后动力响应曲线与原系统吻合较好。

Eigenvalue Reduced-order Method for Dynamic Model

This paper expounds the problem on eigenvalue reduced order for flexible umltibody system model, and derives the eigenvalue modal reduced order oriterion and calculation steps based on Riccati iteration algorithm in accordance with attitude dynamics of flexible spacecraft system.Analysis results indicate that it can reflect better the basic characteristics of the original system than usually eigenvalue truncation criterion and exactly preserve the lower frequencies and mode shapes of the original system.Dynamic response curves of reduced order model accord better with original system.