中文摘要：

对自主设计的太阳帆航天器进行了模态分析，此太阳帆具有套筒式结构展开和帆面多点连接的特点。通过ANSYS有限元软件，分别进行了太阳帆与太阳光线平行和垂直2种姿态时的模态分析；得到了太阳帆航天器在2种姿态下的固有频率和振型。分析结果表明，垂直光线时，太阳帆薄膜承受光压产生应力刚化效应，结构固有频率增大，振型也相应改变。

英文摘要：

This paper presents the modal analysis results of a new solar sail structure, which deploys tube- in- tube booms and multi- point con- nected sails. The finite element software ANSYS is used to undertake the modal analysis. This article focuses on two specific solar sail attitudes in space： one is parallel to sunlight while the other is vertical to sunlight which bears the largest pressure. The natural frequencies and vibration modes are obtained, respectively. The solar sail displays higher natural frequencies in the latter condition for the stress stiffening effect, which is caused by large deformation under solar pressure. And so does the mode shape change accordingly.