为了解决光机系统动力学分析与面形优化过程中由于光机接口程序后处理方式所引起的计算数据量大或接口处理失效的问题, 提出将光机接口处理过程移到有限元前处理中, 并进行了光机系统的集成分析与优化。首先, 为了解决标准Zernike多项式在环形离散点域内的非正交性, 引入了节点面积加权因子和环域Zernike多项式。提出了通过对镜面施加均匀压强求节点支反力的方式求取节点面积加权因子的计算方法。然后采用最小二乘法推导出镜面刚体位移和拟合镜面变形的Zernike多项式系数与镜面各节点变形量之间的线性关系式。最后, 编写接口程序将这些线性表达式以多点约束(MPC)的方式导入到有限元模型中, 在前处理过程中完成系统的光机接口处理过程。通过对非稳态风载引起的某1.2m地基望远镜视轴抖动和液压whiffletree支撑下的主镜镜面高阶变形量进行结构动力学随机响应分析, 验证了光机前处理方法对解决光机系统动力学问题的有效性。此外, 还以镜面面形为优化目标对1.2 m轻量化主镜的镜体结构和尺寸进行敏感度分析, 证明了光机前处理方法可以有效地简化镜面面形的优化分析过程。

In order to solve the problems of large calculation data volume and failure caused by the post processing mode of interface program in the process of optical machine system dynamics analysis and surface shape optimization, the pre-processor was introduced into the opto-mechanical interface processing for integrated analysis and optimization of opto-mechanical system. First, the node area weighting factor and annular Zernike polynomial were introduced to settle non-orthogonality of standard Zernike polynomial within annular discrete field. And a calculation method was proposed to solve node area weighting factor by imposing uniform pressure on mirror surface to solve the bearing reaction force of the node. Then, the least square method was used to deduce the linear relation expression between rigid body deformation of mirror surface,Zernike polynomial coefficients of fitting mirror deformation and deformation of each note on mirror surface. Finally, the interface program was wrote and these linear expressions were channeled to finite element model by the way of Multiple Point Constraint (MPC); what’s more, the systematic interface pre processing of the optical machine was completed. Through making structural dynamics random response analysis on vibration of the bore-sight on 1.2m certain ground-based telescope caused by unsteady state wind load and high-order deformation of the main mirror surface supported by hydraulic whiffletree, the effectiveness of optical machine preprocessing method to the problem of optical machine system dynamics was verified; through taking the shape of the mirror as the optimization objective, the sensitivity analysis was made on the structure size of 1.2m lightweight lens body of primary mirror to verify the optimization analysis process of the mirror shape which was subject to be effectively simplified by the optical preprocessing method.