Design and manufacture of Φ 1.05 m lightweight mirror

Hu Rui; Chen Zhiqiang; Zhang Yuanyuan; Xu Tao; Liu Hong; Zhang Jiyou

doi:10.12086/oee.2020.200317

Article navigation > Opto-Electronic Engineering > 2020 Vol. 47 > No. 10 > 200317

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Hu R, Chen Z Q, Zhang Y Y, et al. Design and manufacture of Φ1.05 m lightweight mirror[J]. Opto-Electron Eng, 2020, 47(10): 200317. doi: 10.12086/oee.2020.200317

Citation:

Hu R, Chen Z Q, Zhang Y Y, et al. Design and manufacture of Φ1.05 m lightweight mirror[J]. Opto-Electron Eng, 2020, 47(10): 200317. doi: 10.12086/oee.2020.200317

Design and manufacture of Φ 1.05 m lightweight mirror

1.
Lightweight Optics and Advanced Materials Center, Institute of Optics and Electronics, Chinese Academy of Science, Chengdu, Sichuan 610209, China
2.
Beijing Institute of Space Mechanics and Electricity, China Academy of Space Technology, China Aerospace Science and Technology Corporation, Beijing 100094, China

More Information

Corresponding author: Liu Hong, E-mail: liuh@ioe.ac.cn

Received Date 20 August 2020

Revised Date 16 September 2020

Published Date 15 October 2020

Abstract

Abstract

In terms of the strict design requirements of Ф1.05 m primary mirrors for space optical systems, a new method of structural optimization design of lightweight mirrors is proposed, and a platform for automatic simulation analysis and optimization design of mirror structures are established. The primary mirror design with excellent performances is determined based on that platform. The primary mirror weighs less than 50 kg, and the lightweight ratio is close to the foreign advanced level. The first mode frequency of the primary mirror under the support of three spherical hinges is 361.2 Hz, and the first-order non-zero free modal frequency is 501.9 Hz. Under the uniform temperature change of 1 ℃, the surface figures with defocus and without defocus are 0.55 nm RMS and 0.10 nm RMS, respectively. The maximum stress of the primary mirror under 30g overload acceleration is 16.1 MPa. All of these performances meet the design requirements. The most advanced third-generation large-aperture mirror processing technology is adopted, and the route is ultra-precision milling, CNC grinding and polishing of small grinding head, and ion beam finishing. In order to ensure the consistency of surface shape test results no matter in the space or on the ground, the gravity unloading technology, and surface shape error data post-processing technology are developed to eliminate the influence of gravity and other systematic errors. The final surface shape accuracy of the primary mirror reaches 0.011 λ RMS, which shows a high precision optical surface and demonstrates the rationality of the scheme.
- space optical system /
- lightweight mirror /
- optimization design /
- optical processing

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References

[1]	张绍华, 徐大龙.美国商业遥感卫星的发展[J].测绘与空间地理信息, 2016, 39(12): 135-138. Google Scholar Zhang S H, Xu D L. The development of commercial remote sensing satellites in the United States[J]. Geomatics & Spatial Information Technology, 2016, 39(12): 135-138. Google Scholar
[2]	朱仁璋, 丛云天, 王鸿芳, 等.全球高分光学星概述(一):美国和加拿大[J].航天器工程, 2015, 24(6): 85-106. Google Scholar Zhu R Z, Cong Y T, Wang H F, et al. Global high-resolution optical satellite overview (1): USA and Canada[J]. Spacecraft Engineering, 2015, 24(6): 85-106. Google Scholar
[3]	范宁, 祖家国, 杨文涛, 等. WorldView系列卫星设计状态分析与启示[J].航天器环境工程, 2014, 31(3): 337-342. Google Scholar Fan N, Zu J G, Yang W T, et al. The design of WorldView satellite and its demonstrative value[J]. Spacecraft Environment Engineering, 2014, 31(3): 337-342. Google Scholar
[4]	Feinberg L D, Dean B H, Hayden W L, et al. Space telescope design considerations[J]. Optical Engineering, 2012, 51(1): 011006. doi: 10.1117/1.OE.51.1.011006 CrossRef Google Scholar
[5]	Liu S T, Hu R, Li Q H, et al. Topology optimization-based lightweight primary mirror design of a large-aperture space telescope[J]. Applied Optics, 2014, 53(35): 8318-8325. doi: 10.1364/AO.53.008318 CrossRef Google Scholar
[6]	Trumper I, Hallibert P, Arenberg J W, et al. Optics technology for large-aperture space telescopes: from fabrication to final acceptance tests[J]. Advances in Optics and Photonics, 2018, 10(3): 644-702. doi: 10.1364/AOP.10.000644 CrossRef Google Scholar
[7]	Kihm H, Yang H S. Design optimization of a 1-m lightweight mirror for a space telescope[J]. Optical Engineering, 2013, 52(9): 091806. doi: 10.1117/1.OE.52.9.091806 CrossRef Google Scholar
[8]	Werner D. WorldView-4's long road to launch about to pay off for DigitalGlobe[J]. Space News, 2016, 27(17): 21-22. Google Scholar
[9]	Watarai H, Katayama H, Niwa T, et al. Development of the wide-swath and high-resolution optical imager onboard advanced optical satellite (ALOS-3)[J]. Proceedings of SPIE, 2019, 11180: 111801Q. Google Scholar
[10]	Lee H, Hahn M. KOMPSAT-3 digital elevation model correction based on point-to-surface matching[J]. Remote Sensing, 2019, 11(20): 2340. doi: 10.3390/rs11202340 CrossRef Google Scholar
[11]	刘书田, 胡瑞, 周平, 等.基于筋板式基结构的大口径空间反射镜构型设计的拓扑优化方法[J].光学精密工程, 2013, 21(7): 1803-1810. Google Scholar Liu S T, Hu R, Zhou P, et al. Topologic optimization for configuration design of web-skin-type ground structure based large-aperture space mirror[J]. Optics and Precision Engineering, 2013, 21(7): 1803-1810. Google Scholar
[12]	Wu J F. Design of high-lightweight space mirror component based on automatic optimization[J]. Journal of Physics: Conference Series, 2020, 1605: 012023. doi: 10.1088/1742-6596/1605/1/012023 CrossRef Google Scholar
[13]	叶鹏程, 潘光, 高山.一种快速优化拉丁超立方试验设计方法[J].西北工业大学学报, 2019, 37(4): 714-723. Google Scholar Ye P C, Pan G, Gao S. Sampling design method of fast optimal Latin hypercube[J]. Journal of Northwestern Polytechnical University, 2019, 37(4): 714-723. Google Scholar
[14]	Lei D, Luo Y J, Wang Y Y, et al. Improved method of hybrid genetic algorithm[J]. Applied Mechanics and Materials, 2014, 556-562: 4014-4017. doi: 10.4028/www.scientific.net/AMM.556-562.4014 CrossRef Google Scholar

Overview

Overview

Overview: Ф 1 m magnitude space optical system has become the core strength in the field of domestic and overseas space observation. It has become one of the hotspots in the field of space optical system development in China because of its great demand and wide application prospect. Considering the launch cost, the space optical system should reduce the structural weight as much as possible. As the core component of the space optical system, the space mirror has a direct impact on the total weight of the system. Effectively reducing the weight of the reflector can greatly reduce the system's launch cost. Under the premise of ensuring the surface precision, the space mirror is developing towards low surface density. The lightweight of mirror has become an important research topic. Compared with developed countries, China lags behind in the field of space optical remote sensing technology. The lightweight mirrors which have been applied in orbit with space optical systems have relatively small aperture and low lightweight level.

In terms of the strict design requirements of Ф 1.05 m primary mirrors for space optical systems, a new method of structural optimization design of lightweight mirrors is proposed, and a platform for automatic simulation analysis and optimization design of mirror structures is established. The primary mirror design with excellent performances is determined based on that platform. The primary mirror weighs less than 50 kg, and the lightweight ratio is close to the foreign advanced level. The first mode frequency of the primary mirror under the support of three spherical hinges is 361.2 Hz, and the first-order non-zero free mode frequency is 501.9 Hz. Under the uniform temperature change of 1 ℃, the surface figures with defocus and without defocus are 0.55 nm RMS and 0.10 nm RMS, respectively. The maximum stress of the primary mirror under 30g overload acceleration is 16.1 MPa. All of these performances meet the design requirements. The most advanced third-generation large-aperture mirror processing technology is adopted, and the route is ultra-precision milling, CNC grinding and polishing of small grinding head, and ion beam finishing. In order to ensure the consistency of surface shape test results no matter in the space or on the ground, the gravity unloading technology and surface shape error data post-processing technology are developed to eliminate the influence of gravity and other systematic errors. The final surface shape accuracy of the primary mirror reaches 0.011 λ RMS, which shows a high precision optical surface and demonstrates the rationality of the scheme.