摘要
极轴式望远镜主镜的面形精度受极轴和赤纬轴复合运动的影响,针对其复杂的运动方式,以Φ700 mm主镜为例,设计了一套满足其各种工况要求的轴向及径向支撑结构。运用有限元分析软件MSC.Patran/Nastran对其在水平和竖直放置的极限工况进行了分析,计算出主镜水平状态下的镜面变形误差PV值为19.33 nm,RMS值为4.47 nm;竖直状态下当极角θ为0°时,镜面变形误差PV值为16.19 nm,RMS值为1.26 nm,当极角θ为30°时,镜面变形误差PV值为13.33 nm,RMS值为1.19 nm。分析结果满足设计指标所要求的RMS<λ/20,PV<λ/4(λ=632.8 nm),证实了该支撑方案可行。
The primary mirror surface deformation of equatorial telescope is affected by the composite motion of polar axis and declination axis.According to the complicated mode of motion,the axial and radial supports on Φ700 mm primary mirror were designed to meet any load cases.Some utmost load cases were analyzed with the finite element analysis software MSC.Patran/Nastran when the mirror was level and vertical.As a result,when the mirror is level,the surface deformation error PV value is 19.33 nm,RMS value is 4.47 nm;when the mirror is vertical,as the polar angle θ is 0°,the surface deformation error PV value is 16.19 nm,RMS value is 1.26 nm,as the polar angle θ is 30°,the surface deformation error PV value is 13.33 nm,RMS value is 1.19 nm.The results satisfy all the precision requirements RMSλ/20,PVλ/4（λ=632.8 nm）,and it proves that the support way is feasible.
出处
《红外与激光工程》
EI
CSCD
北大核心
2011年第3期476-479,共4页
Infrared and Laser Engineering
基金
国家863计划资助项目(2009AA808020)
关键词
极轴式望远镜
主镜
支撑
有限元法
equatorial telescope
primary mirror
support
finite element method
