Evaluation of the Performance of the GSSM Under Vibration Based on Normalized Point Source Sensitivity

基于归一化点源敏感性的GSSM振动影响评价

安其昌^1,2,张景旭¹,杨飞¹,赵宏超¹

（1.中国科学院长春光学精密机械与物理研究所,长春 130033;

2.中国科学院大学,北京 100039）

创新点说明：

1）深入研究了振动对于GSSM光学中继作用的影响,并建立与PSSn的联系;

2）引入统计矩的方法获得GSSM在任意可测载荷下的光学传递函数;

3）引入功率谱的方法获得GSSM在统计载荷下的光学传递函数。

中文摘要：

巨型可控科学反射镜系统（GSSM）是国际合作项目30 m望远镜（TMT）的三镜。为全面研究GSSM 在振动下的光学传递能力的降低,本文引入了归一化点源敏感性（PSSn）以实现在整个频域上全面地评价系统所受到的影响。首先,介绍了PSSn的基本概念和定义,推导了在大气视宁占主导情况下系统PSSn的计算方法,为GSSM的概念设计与误差估计提供理论依据。之后,对在可测的任意载荷及符合统计规律的载荷（如风载）这两类载荷下的系统光学传递函数的计算方法进行了研究。在任意载荷下使用的是所测得振动的高阶统计矩,通过数值的方法来获得系统的光学传递函数;而对于符合统计规律的载荷,使用功率谱来进行分析。通过实测结合仿真得到GSSM在上述两种情况下PSSn从0.996分别下降到0.994和0.991。本文的研究,建立了GSSM所受振动与PSSn之间的关系,可以为系统工程师在进行GSSM以及TMT的误差分配过程中提供参考。同时由于PSSn良好的合成特性,可以结合其他误差项一起考虑。

关键词：三十米望远镜;标准化点源敏感性;光学传递函数;机械振动

     

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