HAN Chun-yang, XU Zhen-bang, WU Qing-wen etc. Optimization design and error distribution for secondary mirror adjusting mechanism of large optical payload[J]. Editorial Office of Optics and Precision Engineering, 2016,24(5): 1093-1103
HAN Chun-yang, XU Zhen-bang, WU Qing-wen etc. Optimization design and error distribution for secondary mirror adjusting mechanism of large optical payload[J]. Editorial Office of Optics and Precision Engineering, 2016,24(5): 1093-1103 DOI: 10.3788/OPE.20162405.1093.
Optimization design and error distribution for secondary mirror adjusting mechanism of large optical payload
A Hexapod precision positioning platform called the Secondary Mirror Adjustment Mechanism(SMAM) was designed to precisely adjust the second mirror of a large optical payload. The structure configurations were optimized based on the multi-objective function
and the errors of each strut and the upper (lower) hinges were distributed by the optimization algorithm. A kinematic model and a static flexibility model for the Hexapod platform were established
and the influences of main structure parameters on the mechanism performance were analyzed. Then
the positioning accuracy and anti-deformation indexes were put forward. By using the structural parameters as variables
the optimization functions were established
and two single-objective functions were optimized by the genetic algorithm. At the same time
a unified constraint function of weight factor was constructed
and the multi-objective function was also optimized by the genetic algorithm. Afterwards
a nonlinear optimized error distribution model was established
and it was used to distribute the errors for each strut and the upper (lower) hinges. Finally
by testing the performance indexes of a prototype
the efficiency of the proposed method was verified. The research results after optimization show that the positioning accuracy and the anti-deformation capacity are improved by 8.3% and 62.5%
respectively. The upper and lower hinge error bounds increase from 2.7
μ
m to 6.3
μ
m
and each strut error bound increases from 1.3
μ
m to 3.2
μ
m. Moreover
the relative positing accuracy and the static stiffness of
Z
axis are 0.6% and 41.14 N/
μ
m
respectively. The research in this paper improves the positioning accuracy and anti-deformation ability
and saves the design cycles and processing costs.
关键词
Keywords
references
杨剑锋,徐振邦,吴清文,等. 空间光学载荷六维隔振系统设计及特性分析[J]. 光学精密工程, 2015, 23(5):143-153. YANG J F, XU ZH B, WU Q W, et al..Design of six dimensional vibration isolation system for space optical payload[J].Opt.Precision Eng., 2015, 23(5):143-153.(in Chinese)
贾学志, 王栋, 张雷, 等. 轻型空间相机调焦机构的优化设计与精度试验[J]. 光学精密工程, 2011, 19(8):1824-1831. JIA X ZH, WANG D, ZHANG,et al..Optimizing design and precision experiment of focusing mechanism in lightweight space camera[J].Opt.Precision Eng., 2011, 19(8):1824-1831.(in Chinese)
GEIJO E M, CASALTA J M, CANCHADO M, et al.. VISTA secondary mirror drive performance and test results[C].Astronomical Telescopes and Instrumentation. International Society for Optics and Photonics, 2006:627338-627338-10.
DOUGLAS R N, RYAN S, JAKE D, et al.. Baseline design of the LSST hexapods and rotator[J].SPIE,2014,9151:91512B-1-16.
SEBRING T A, DUNHAM E W, MILLIS R L. The discovery channel telescope:a wide-field telescope in northern arizona[C].Astronomical Telescopes and Instrumentation. International Society for Optics and Photonics, 2004:658-666.
CASA LTA J M, ARINO J, CANCH ADO M, et al..The performances of GTC secondary mirror drive unit[J].SPIE, 2004, 5495:507-517.
徐刚, 杨世模, 龚雨兵. 大型光学望远镜副镜位姿精调机构的优化设计[J]. 光学精密工程, 2008, 16(7):1181. XU G, YANG SH M, GONG Y B. Optimal design of pose and position fine tuning apparatus for secondary mirror in large optical telescope[J]. Opt.Precision Eng., 2008, 16(7):1181. (in Chinese)
王永, 姚太克, 周烽, 等. 望远镜副镜的三自由度并联支撑构型研究与运动分析[J]. 光学精密工程, 2013, 21(11):2860-2869. WANG Y, YAO T K, ZHOU F, et al.. Type synthesis of 3-DOF parallel support system for telescope secondary mirror[J]. Opt.Precision Eng., 2013, 21(11):2860-2869. (in Chinese)
MERLET J. Parallel robots, second ed[M].Springer-Verlag New York Inc, 2006.
VON DAAKE A, VETTER C, BÖHM E, et al..Contribution to calibration of hexapod positioning units in industrial environment[J].Precision Engineering, 2013, 37(1):73-80.
HUANG T, DEREK G. A general and novel approach for parameter identification of 6-DOF parallel kinematic machines[J]. Mechanism and Machine Theory, 2005, 40(2):219-239.
ARSENAULT M, BOUDREAU R. Synthesis of planar parallel mechanisms while considering workspace, dexterity, stiffness and singularity avoidance[J]. Journal of Mechanical Design, 2006, 128(1):69-78.
SONG J, MOU J I, KING C. Parallel kinematic machine positioning accuracy assessment and improvement[J]. Journal of Manufacturing Processes, 2000, 2(1):48-58.
YAO R, TANG X, LI T, et al..Error analysis and distribution of 6-SPS and 6-PSS reconfigurable parallel manipulators[J]. Tsinghua Science & Technology, 2010, 15(5):547-554.
SU Y X, DUAN B Y, ZHENG C H. Genetic design of kinematically optimal fine tuning Stewart platform for large spherical radio telescope[J]. Mechatronics, 2001, 11(7):821-835.
段学超, 仇原鹰, 段宝岩. 基于自适应遗传算法的Stewart平台结构双目标优化设计[J]. 计算力学学报, 2007, 23(6):718-721. DUNA X CH,CHOU Y Y, DUAN B Y. Bi-objective optimization of structural parameters of the Stewart platform based on adaptive genetic algorithm[J].Chinese Journal of Computational Mechanics, 2007, 23(6):718-721.(in Chinese)
JAEHOON L,JOSEPH D, KENNETH H H. A practical quality index based on the octahedral manipulator[J].J.of Robotics Research, 1998,17(10):1081-1090.
MERLET J P. Jacobian, manipulability, condition number, and accuracy of parallel robots[J]. Journal of Mechanical Design, 2006, 128(1):199-206.
ZHANG D, WANG L, LANG S Y. Parallel kinematic machines:design, analysis and simulation in an integrated virtual environment[J].Journal of Mechanical Design, 2005, 127(4):580-588.
黄真,赵永生,赵铁石. 高等空间机构学[M]. 北京:高等教育出版社,2006. HUANG ZH, ZHAO Y SH, ZHAO T SH. Advanced Spatial Mechanism [M].Beijing:Chinese High Education Press,2006.(in Chinese)
SNEED R C, KEAS P J. Error reduction and modeling for hexapod positioners of secondary mirrors for large ground-based telescopes[C].SPIE Astronomical Telescopes Instrumentation. International Society for Optics and Photonics, 2014:915020-915020-14.
张景旭,安其昌,李剑锋,等. 基于机构条件数的30 m望远镜三镜Stewart平台[J]. 光学精密工程,2014,22(4):890-897. ZHANG J X, AN Q CH, LI J F, et al.. Third mirror Stewart platform of TMT based on mechanism condition number[J].Opt.Precision Eng., 2014,22(4):890-897.(in Chinese)
CHUNSHEN L. Precision design of modular parallel kinematic machines[J]. Tool Engineering, 2007, 41(8):38.
SNEED R C, CASH M F, CHAMBERS T S, et al.. Six degrees of freedom, sub-micrometer positioning system for secondary mirrors[C].SPIE Astronomical Telescopes+Instrumentation. International Society for Optics and Photonics, 2010:77332R-77332R-11.