大口径望远镜次镜调整机构的技术研究
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摘要
次镜作为大口径望远镜系统的重要组成部分,其各个方面都需要做详尽的理论分析和研究,以满足系统的要求。本文以卡塞格林式反射望远镜为例,取口径为Φ315mm的次镜作为研究对象,在对其轻量化设计和支撑优化设计的基础上,进行多自由度调整机构的设计,为所在研的某大口径望远镜项目提供参考。
本文在查阅大量文献的基础上,全面地介绍了国内外大口径望远镜中次镜结构系统的发展现状,对其中关键结构技术做了对比分析,提出了一种能满足项目要求的次镜结构系统设计方案。
在理论分析和传统经验的基础上,对次镜进行轻量化设计和支撑结构优化设计,并建立相应的有限元模型,对次镜的面形精度进行有限元分析。为了满足主次镜光轴的准直性要求,设计了一套组合型的五自由度次镜调整机构,它由二维XY移动平台和三自由度Tip/Tilt/Focus平台组成。二维XY移动平台的功能是调整次镜在X、Y方向的横向偏心误差,它由两个单向平移台串联而成,采用手轮驱动、精密丝杠传动与交叉滚柱导轨导向的方式实现次镜的移动。三自由度Tip/Tilt/Focus平台用于实现次镜的轴向离焦及倾斜的校正,它由基座、驱动器和动平台组成,驱动器和动平台之间由柔性铰链连接,通过驱动器的伸缩和柔性铰链的弯曲来实现动平台的三自由度运动。文中对三自由度平台的运动学原理进行了详细介绍,对柔性铰链的原理和设计进行了深入的探讨。
论文最后对设计的次镜结构系统进行有限元仿真分析,验证了次镜结构系统的可行性,并对后续工作进行了展望。
The secondary mirror is one of the most important part of large-aperture telescope system. It is necessary to research and analyze the theory thoroughly to satisfy the requirement of the system. Based on a 315mm diameter secondary mirror in Cassegrain telescope msystem,mutil-degree of freedom adjustment mechanism of the secondary mirror was planed after lightweighting the secondary mirror and optimizing its support systemeight design, which could provide reference for large-aperture telescope project.
The development of the secondary mirror structure was introduced comprehensively both at home and abroad, and the key structural techniques were compared. Finally a structure scheme for secondary mirror was put forward which would fit the requirements of the system.
Based on theoretical analysis and traditional experience, the lightweight design and optimal support for secondary mirror was carried out, and the corresponding finite element model was built. The surface precision of the mirror was analyzed. To meet alignment accuracy between primary and secondary mirror, a combined five-degree of freedom adjustment mechanism for secondary mirror was introduced, including a XY displacement platform and a Tip/Tilt/Focus stage. The XY platform, consisted of two one-way translation platform driving by hand wheel, transmitted by precision leadscrew and supported by cross roller guider, is to correct the eccentric error of X and Y direction. The Tip/Tilt/Focus stage, composed of three actuators, base and moving platform, is to adjust defocus and tip/tilt error. The moving platform and actuators were connected by flexure hinges, and the motion of the platform was performed by the extension of three actuators and the rotation of flexure hinges.The kinematic principle of three-dimension platform was presented in detail and the theory of flexure hinges was discussed detailedly.
At last,the finite element simulation analysis of structural system of secondary mirror was done, verified the feasibility of the designed mechanism,furthermore some expectations were proposed for the future work.
本文在查阅大量文献的基础上,全面地介绍了国内外大口径望远镜中次镜结构系统的发展现状,对其中关键结构技术做了对比分析,提出了一种能满足项目要求的次镜结构系统设计方案。
在理论分析和传统经验的基础上,对次镜进行轻量化设计和支撑结构优化设计,并建立相应的有限元模型,对次镜的面形精度进行有限元分析。为了满足主次镜光轴的准直性要求,设计了一套组合型的五自由度次镜调整机构,它由二维XY移动平台和三自由度Tip/Tilt/Focus平台组成。二维XY移动平台的功能是调整次镜在X、Y方向的横向偏心误差,它由两个单向平移台串联而成,采用手轮驱动、精密丝杠传动与交叉滚柱导轨导向的方式实现次镜的移动。三自由度Tip/Tilt/Focus平台用于实现次镜的轴向离焦及倾斜的校正,它由基座、驱动器和动平台组成,驱动器和动平台之间由柔性铰链连接,通过驱动器的伸缩和柔性铰链的弯曲来实现动平台的三自由度运动。文中对三自由度平台的运动学原理进行了详细介绍,对柔性铰链的原理和设计进行了深入的探讨。
论文最后对设计的次镜结构系统进行有限元仿真分析,验证了次镜结构系统的可行性,并对后续工作进行了展望。
The secondary mirror is one of the most important part of large-aperture telescope system. It is necessary to research and analyze the theory thoroughly to satisfy the requirement of the system. Based on a 315mm diameter secondary mirror in Cassegrain telescope msystem,mutil-degree of freedom adjustment mechanism of the secondary mirror was planed after lightweighting the secondary mirror and optimizing its support systemeight design, which could provide reference for large-aperture telescope project.
The development of the secondary mirror structure was introduced comprehensively both at home and abroad, and the key structural techniques were compared. Finally a structure scheme for secondary mirror was put forward which would fit the requirements of the system.
Based on theoretical analysis and traditional experience, the lightweight design and optimal support for secondary mirror was carried out, and the corresponding finite element model was built. The surface precision of the mirror was analyzed. To meet alignment accuracy between primary and secondary mirror, a combined five-degree of freedom adjustment mechanism for secondary mirror was introduced, including a XY displacement platform and a Tip/Tilt/Focus stage. The XY platform, consisted of two one-way translation platform driving by hand wheel, transmitted by precision leadscrew and supported by cross roller guider, is to correct the eccentric error of X and Y direction. The Tip/Tilt/Focus stage, composed of three actuators, base and moving platform, is to adjust defocus and tip/tilt error. The moving platform and actuators were connected by flexure hinges, and the motion of the platform was performed by the extension of three actuators and the rotation of flexure hinges.The kinematic principle of three-dimension platform was presented in detail and the theory of flexure hinges was discussed detailedly.
At last,the finite element simulation analysis of structural system of secondary mirror was done, verified the feasibility of the designed mechanism,furthermore some expectations were proposed for the future work.
引文
[1]蒋世仰.现代大型光学望远镜巡礼[J].中国国家天文,2008,06:66-74.
[2]张景旭.大口径地基光电望远镜结构总体研究[D].中科院博士学位论文,2008.
[3] K Miyawaki,N Itoh,R Sugiyama,et al.Mechanical structure for the Subaru telescope[J].SPIE, 1994,Vol.2199:754-762.
[4] D Mancini, G Mancini, F Perrotta,et al.VST Project:Mechanical Design Optimization[J]. SPIE,2003,Vol.4837:379-388.
[5] P Schipani, F Perrotta, C Molfese, et al. The VST Secondary Mirror Support System[J]. SPIE, 2008, Vol.7018:4501-4510.
[6] A M Mcpherson, A J Born, J P Emerson, et al. VISTA:status, performance,and lessons[J]. SPIE, 2006,Vol.6267:1452-1463.
[7] Magomed A Abdulkadyrov, Alexey P Patrikeev, Sergey P Belousov, et al. M2 Secondary Mirror Manufacturing for VISTA Project[J]. SPIE, 2008, Vol.7018:B1-B9.
[8] Enric Martin Geijo, Joan Manel Casalta, Manuel Canchado, et al. VISTA Secondary Mirror Drive Performance and Test Results[J]. SPIE, 2006, Vol.6273:3801-3810.
[9] Lorenzo Zago, Pierre Genequand and Joseph Moerschell. Extremely compact secondary mirror unit for the SOFIA telescope capable of 6-degree-of-freedom aligment plus chopping[J]. SPIE, 1998, Vol 3352:666-674.
[10] L Zago,Ph Schwab and D Gallieni.Development and testing of a high-precision,high-stiffness linear actuator for the focus-center mechanism of the SOFIA secondary mirror[J]. SPIE, 2000, Vol.4014:392-398.
[11] Michel FRUIT, Pascal ANTOINE, Jean-Luc VARIN, et al. Development of the SOFIA Silicon Carbide Secondary mirror[J]. SPIE, 2003, Vol.4857:274-285.
[12] Pierre Y Bely. The design and construction of large optical telescopes[M]. Springer, 2002.
[13] http://dns4.pd.astro.it/planets/tngproject/spec.html, 1996.
[14] Claudio Pernechele, Favio Bortoletto,Klaus Reif. Position control for active secondary mirror of a two-mirror telescope[J]. SPIE, 1997, Vol.3112:172-180.
[15] A Riccardi, G.brusa, P Salinari. et al. Adaptive Secondary Mirrors for the Large Binocular Telescope[J]. SPIE, 2003, Vol.4839:721-732.
[16] P M Gray, S C West & W Gallieni. Support and Actuation of Six Secondaries for the 6.5m MMT and 8.4m LBT Telescopes[J]. SPIE, 1997, Vol.2871:374-384.
[17] P Schipani, L Marty. Steward platform kinematics and secondary mirror aberration control[J].SPIE, 2006, vol.6273: B1-B12.
[18] P Schipani, L Ferragina, L Marty, et al. Parallel Robots in a Ground-based Telescope Active Optics System:Theory and Experiments[J]. SPIE, 2007, Vol.6715:301-309.
[19] YODER. JR. PAUL R. Opto-Mechanical systems design [M]. Marcel Dekker, Inc.New York, 1993.
[20]吴清文.空间相机中主镜的轻量化技术及其应用[J].光学精密工程, 1997, 5(6):69-80.
[21]国绍文,王武义,张广玉等.空间光学系统反射镜轻量化技术综述[J].光学仪器,2005, 27(4):78-82.
[22]胡企千.大型光学镜子的结构、支撑及重力变形计算方法[J].光学机械, 1983, 6:29-44.
[23] Pravin K Mehta. Flexural rigidty characteristics of light-weighted mirrors[J]. SPIE, 1987,Vol.748:158-171.
[24]吴清彬,陈时锦,董申.参数优化方法在轻质反射镜结构设计中的应用[J].光学精密工程,2003,11(5):466-471.
[25] Vukobratovich,D. ,Lightweight laser communications mirrors made with metal foam cores[J]. SPIE, 1989, Vol.1044:216-227.
[26]黄启泰.轻量化碳化硅反射镜支撑方案分析[D].苏州大学硕士学位论文,2004
[27]张学军,李志来,张忠玉.基于SiC材料的空间相机非球面反射镜结构设计[J].红外与激光工程,2007,36(5):577-582.
[28]曾勇强,傅丹鹰,孙纪文等.空间遥感器大口径反射镜支撑结构型式综述[J].航天返回与遥感,2006,38(2):18-23.
[29] R.N.Wilson, F.Franza and L.Noethe. Active Optics I:a system for optimizing the optical quality and reducing the costs of large telescopes[J]. Journal of Modern Optics, 1987, Vol.34:485-509.
[30] R N Wilson, F Franza and L Noethe. Active Optics IV:set-up and performance of optics of the ESO New Technology Telescope(NTT) in the observatory[J]. Journal of Modern Optics, 1991, Vol.38:219-243
[31]苏定强,崔向群.主动光学—新一代大望远镜的关键技术[J].天文学进展,1999,17(1):1-14.
[32]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,2005.
[33]程景全.天文望远镜原理和设计[M].北京:中国科学技术出版社,2002.
[34] Miyawaki,K., Itoh,N. Mechanical Structure for the Subaru Telescope[J], SPIE, 1994, Vol.2199:754-768.
[35] Stewart. A Platform with six degree of freedom[J]. Proceedings of the Institute of Mechanical Engineers,1965,180(15):371-386.
[36] K.H.Hunt. Structural Kinematic of in-Parallel-Actuated Robot Arms[J]. Journal of Mechanisms, Transmissions and Automation in Design, 1983(105):705-715.
[37] L.W.Tsai,G.C.Walsh,R.E.Stamper. Kinematics of a Novel Three DOF Translational Platform[J]. Proceedings of IEEE International Conference on Robotics and Automation,1996:3446-3451.
[38] Friso Klinkhamer,TNO TPD,Delft,et al.An adjustment for five degrees of freedom as an alternative for a hexapod mechanism[J]. SPIE, 2003, Vol.5176:108-113.
[39]朱思俊.少自由度并联机构运动学及五自由度并联机构的相关理论[D].燕山大学工学博士论文,2007.
[40]毕树生,王守杰,宗光华.串并联微动机构的运动学分析[J].机器人,1997(7):259-264.
[41]赵玮,于靖军,毕树生等.串并联微操作机器人系统的研究[J].北京航空航天大学学报,2001,27(6):623-627.
[42]郭喜庆,王越勇.大口径反射镜几种轻量化孔结构形式的分析[J].光学精密工程,2000,8(6):518-521.
[43] R. N. Wilson. Reflecting telescope opticsⅡ[M]. Springer, 2001.
[44]谭徽松.光学反射望远镜主、副镜安装调整不良引起的像差[J].云南天文台台刊,2003(3):5-61.
[45]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):1181-1189.
[46]盛鸿亮等.精密机构与结构设计[M].北京:北京理工大学出版社,1993.
[47]机械设计手册编委会.机械设计手册(新版第二版)[M].北京:机械工业出版社,2004.
[48]机械工程手册编辑委员会.机械工程手册,第二版,机械零部件设计卷[M].北京:机械工业出版社,1995.
[49]陈知泰,余跃庆,杜兆才.柔顺机构自由度的一种简化计算方法[J].北京工业大学学报,2005,31(3):225-228.
[50]夏尊凤,许焰.柔性构件和柔性机构自由度分析[J].机械设计,2009,26(4):51-53.
[51]李庆祥,王东生,李玉和.现代精密仪器设计[M].北京:清华大学出版社,2003.
[2]张景旭.大口径地基光电望远镜结构总体研究[D].中科院博士学位论文,2008.
[3] K Miyawaki,N Itoh,R Sugiyama,et al.Mechanical structure for the Subaru telescope[J].SPIE, 1994,Vol.2199:754-762.
[4] D Mancini, G Mancini, F Perrotta,et al.VST Project:Mechanical Design Optimization[J]. SPIE,2003,Vol.4837:379-388.
[5] P Schipani, F Perrotta, C Molfese, et al. The VST Secondary Mirror Support System[J]. SPIE, 2008, Vol.7018:4501-4510.
[6] A M Mcpherson, A J Born, J P Emerson, et al. VISTA:status, performance,and lessons[J]. SPIE, 2006,Vol.6267:1452-1463.
[7] Magomed A Abdulkadyrov, Alexey P Patrikeev, Sergey P Belousov, et al. M2 Secondary Mirror Manufacturing for VISTA Project[J]. SPIE, 2008, Vol.7018:B1-B9.
[8] Enric Martin Geijo, Joan Manel Casalta, Manuel Canchado, et al. VISTA Secondary Mirror Drive Performance and Test Results[J]. SPIE, 2006, Vol.6273:3801-3810.
[9] Lorenzo Zago, Pierre Genequand and Joseph Moerschell. Extremely compact secondary mirror unit for the SOFIA telescope capable of 6-degree-of-freedom aligment plus chopping[J]. SPIE, 1998, Vol 3352:666-674.
[10] L Zago,Ph Schwab and D Gallieni.Development and testing of a high-precision,high-stiffness linear actuator for the focus-center mechanism of the SOFIA secondary mirror[J]. SPIE, 2000, Vol.4014:392-398.
[11] Michel FRUIT, Pascal ANTOINE, Jean-Luc VARIN, et al. Development of the SOFIA Silicon Carbide Secondary mirror[J]. SPIE, 2003, Vol.4857:274-285.
[12] Pierre Y Bely. The design and construction of large optical telescopes[M]. Springer, 2002.
[13] http://dns4.pd.astro.it/planets/tngproject/spec.html, 1996.
[14] Claudio Pernechele, Favio Bortoletto,Klaus Reif. Position control for active secondary mirror of a two-mirror telescope[J]. SPIE, 1997, Vol.3112:172-180.
[15] A Riccardi, G.brusa, P Salinari. et al. Adaptive Secondary Mirrors for the Large Binocular Telescope[J]. SPIE, 2003, Vol.4839:721-732.
[16] P M Gray, S C West & W Gallieni. Support and Actuation of Six Secondaries for the 6.5m MMT and 8.4m LBT Telescopes[J]. SPIE, 1997, Vol.2871:374-384.
[17] P Schipani, L Marty. Steward platform kinematics and secondary mirror aberration control[J].SPIE, 2006, vol.6273: B1-B12.
[18] P Schipani, L Ferragina, L Marty, et al. Parallel Robots in a Ground-based Telescope Active Optics System:Theory and Experiments[J]. SPIE, 2007, Vol.6715:301-309.
[19] YODER. JR. PAUL R. Opto-Mechanical systems design [M]. Marcel Dekker, Inc.New York, 1993.
[20]吴清文.空间相机中主镜的轻量化技术及其应用[J].光学精密工程, 1997, 5(6):69-80.
[21]国绍文,王武义,张广玉等.空间光学系统反射镜轻量化技术综述[J].光学仪器,2005, 27(4):78-82.
[22]胡企千.大型光学镜子的结构、支撑及重力变形计算方法[J].光学机械, 1983, 6:29-44.
[23] Pravin K Mehta. Flexural rigidty characteristics of light-weighted mirrors[J]. SPIE, 1987,Vol.748:158-171.
[24]吴清彬,陈时锦,董申.参数优化方法在轻质反射镜结构设计中的应用[J].光学精密工程,2003,11(5):466-471.
[25] Vukobratovich,D. ,Lightweight laser communications mirrors made with metal foam cores[J]. SPIE, 1989, Vol.1044:216-227.
[26]黄启泰.轻量化碳化硅反射镜支撑方案分析[D].苏州大学硕士学位论文,2004
[27]张学军,李志来,张忠玉.基于SiC材料的空间相机非球面反射镜结构设计[J].红外与激光工程,2007,36(5):577-582.
[28]曾勇强,傅丹鹰,孙纪文等.空间遥感器大口径反射镜支撑结构型式综述[J].航天返回与遥感,2006,38(2):18-23.
[29] R.N.Wilson, F.Franza and L.Noethe. Active Optics I:a system for optimizing the optical quality and reducing the costs of large telescopes[J]. Journal of Modern Optics, 1987, Vol.34:485-509.
[30] R N Wilson, F Franza and L Noethe. Active Optics IV:set-up and performance of optics of the ESO New Technology Telescope(NTT) in the observatory[J]. Journal of Modern Optics, 1991, Vol.38:219-243
[31]苏定强,崔向群.主动光学—新一代大望远镜的关键技术[J].天文学进展,1999,17(1):1-14.
[32]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,2005.
[33]程景全.天文望远镜原理和设计[M].北京:中国科学技术出版社,2002.
[34] Miyawaki,K., Itoh,N. Mechanical Structure for the Subaru Telescope[J], SPIE, 1994, Vol.2199:754-768.
[35] Stewart. A Platform with six degree of freedom[J]. Proceedings of the Institute of Mechanical Engineers,1965,180(15):371-386.
[36] K.H.Hunt. Structural Kinematic of in-Parallel-Actuated Robot Arms[J]. Journal of Mechanisms, Transmissions and Automation in Design, 1983(105):705-715.
[37] L.W.Tsai,G.C.Walsh,R.E.Stamper. Kinematics of a Novel Three DOF Translational Platform[J]. Proceedings of IEEE International Conference on Robotics and Automation,1996:3446-3451.
[38] Friso Klinkhamer,TNO TPD,Delft,et al.An adjustment for five degrees of freedom as an alternative for a hexapod mechanism[J]. SPIE, 2003, Vol.5176:108-113.
[39]朱思俊.少自由度并联机构运动学及五自由度并联机构的相关理论[D].燕山大学工学博士论文,2007.
[40]毕树生,王守杰,宗光华.串并联微动机构的运动学分析[J].机器人,1997(7):259-264.
[41]赵玮,于靖军,毕树生等.串并联微操作机器人系统的研究[J].北京航空航天大学学报,2001,27(6):623-627.
[42]郭喜庆,王越勇.大口径反射镜几种轻量化孔结构形式的分析[J].光学精密工程,2000,8(6):518-521.
[43] R. N. Wilson. Reflecting telescope opticsⅡ[M]. Springer, 2001.
[44]谭徽松.光学反射望远镜主、副镜安装调整不良引起的像差[J].云南天文台台刊,2003(3):5-61.
[45]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):1181-1189.
[46]盛鸿亮等.精密机构与结构设计[M].北京:北京理工大学出版社,1993.
[47]机械设计手册编委会.机械设计手册(新版第二版)[M].北京:机械工业出版社,2004.
[48]机械工程手册编辑委员会.机械工程手册,第二版,机械零部件设计卷[M].北京:机械工业出版社,1995.
[49]陈知泰,余跃庆,杜兆才.柔顺机构自由度的一种简化计算方法[J].北京工业大学学报,2005,31(3):225-228.
[50]夏尊凤,许焰.柔性构件和柔性机构自由度分析[J].机械设计,2009,26(4):51-53.
[51]李庆祥,王东生,李玉和.现代精密仪器设计[M].北京:清华大学出版社,2003.