第21卷第11期 2013年11月
文章编号
1004-924X(2013)11-2860-10
光学精密工程
Opties and Precision Engineering
Vol. 21No. 11
Nov.2013
望远镜副镜的三自由度并联支撑构型研究与运动分析
王永1，姚太克1，周烽，张丽敏？
（1.中国科学技术大学自动化系，安徽合肥230027；
2.中国科学院长春光学精密机械与物理研究所，吉林长春130033）
摘要：针对望远镜副镜姿态和焦距自动调整的需求，设计了副镜三自由度并联支撑机构构型，分析了它们的运动学特性并讨论了构型的选取。首先，基于约束螺旋理论，设计了对称三支链两转一移并联机构的构型；根据副镜支撑运动副尽可能少、低惯性、直线驱动等要求，选取了12种可行构型。然后，针对12种可行构型，根据驱动输人特点和支链约束特性，提出分类建模思想，并建立了统一运动学模型；引人ZXZ欧拉角法描述机构姿态，简化了姿态空间和伴随运动的表达和分析方式。最后，以1.2m口径望远镜系统为例，仿真研究了副镜并联支撑机构的伴随运动。结果表明，支链约束力线矢平行静
平台的7种构型具有更小的伴随运动，不大于0.27mm，该项研究为后续的精度和刚度特性研究提供了基础。关键词：望选镜；副镜；三自由度并联支撑；构型设计；运动学建模；伴随运动
中图分类号：TH743
文献标识码：A
doi;10. 3788/OPE, 20132111.2860
Typesynthesisof3-DOFparallel
support systemfortelescope secondarymirror WANG Yong',YAO Tai-ke', ZHOU Feng', ZHANG Li-min(l.Departmentof Automation,Universityof Scienceand
Technologyof China,Hefei 230027,China;
2.Changchun Institute of Optics,Fine Mechanics and Physics,
ChineseAcademyof Sciences,Changchun130033,China) Correspondingauthor,E-mail:yongwang@ustc.edu.cn
Abstract: To realize tip/tilt and focus adjustment for a telescope secondary mirror, several types of parallel support systems were designed and their dynamic characteristics and construct selection were analyzed. First, the screw theory was used to realize the type synthesis for 2R1T (two-rotation and one-translation degrees of freedom) parallel mechanisms with 3 symmetrical branches. 12 types of fea sible mechanisms with the fewest joint in each branch, the smallest inertia and linear actuators were selected for the support systems, Then, the selected mechanisms were classified according to the actu-ating characteristics and constraint properties and the kinematics models were established respective ly, including actuation models and constraint models. Moreover, ZXZ Euler angels were introduced to describe the orientation of moving platform and to simplify the description and analysis of orienta tion and parasitic motion for 2R1T parallel mechanisms. Finally, a 1. 2 m telescope was taken as an il-
收稿日期：2013-05-12；修订日期：2013-06-17
基金项目：中国科技大学-长春光学精密机械与物理研究所超精密控制与系统联合实验室资助项目