微衛星近年已成為使用太空資源與環境時，相當重要的工具，由於經費需求較少，逐漸發展成大學的太空實驗平台。PACE衛星為國立成功大學在台南研發之自主微衛星，主要的任務為提供在太空之姿態控制實驗，而此實驗尚未實現於微衛星上。PACE衛星之結構依循著CubeSat標準規格，其中定義了設計時的尺寸限制與最大重量。此結構體將可延續用於成功大學下一世代的微衛星，以節省經費與研究時間。為達此目的，目前的結構設計必須改良，此為本論文之目的。本論文提出一最佳化的結構體，可提高微衛星對環境的規格，例如增加可用載重、提昇系統自然頻率等。結構設計工具與觀念已有許多相關的研究，也提昇了以電腦輔助設計與結構模擬的可行性。不同部份的結構可透過模擬被改良、修正並評估，而所有的元件可分別組裝，而最終將把所有元件組合完成在一起模擬並進行確認。本論文主要闡述與PACE衛星團隊合作的經驗，並且提供成功大學未來微衛星計畫的平台。

Nanosatellites are useful tools increasingly being developed in universities throughout the world, as they provide an affordable and easy access to space. PACE is the first indigenous nanosatellite developed at the National Cheng Kung University (NCKU) in Tainan, Taiwan. The primary purpose of the PACE mission is to carry out active attitude control experiments in space, which has never been done in a nanosatellite. The structure developed for PACE follows the CubeSat standard. This specifies the dimensions and maximum mass the spacecraft has to meet. For the next generation of NCKU's nanosatellites, the same structure plat-form could be used which would be valuable in terms of cost and of study time. But to allow this, improvements have to be made to the current structure design. This is the purpose of this thesis, which proposes to optimize the structure to meet higher requirements, i.e. increase the available payload mass, elevate the natural frequencies of the system, etc. Structural optimization tools and concepts have been used to carry out most of the study, which implied the use of computer aided design and mechanical simulations. Different parts of the structure have been modified, improved and assessed through the simulations. All these changes can be integrated one by one, and a final design including them all is proposed. The work of this thesis together with the experience gained on PACE provide a precious combination for the future nanosatellite projects of NCKU.

[1] Definition by the Surrey Satellites Technology Ltd (SSTL), University of Surrey, Guildford, UK.
[2] J. Rotteveel, University CubeSat Projects Sector Overview. ISIS, 2007.
[3] Clyde Space, 2010: http://www.clyde-space.com.
[4] Pumpkin Inc., 2009: http://www.cubesatkit.com.
[5] GOM Space, 2009: http://www.gomspace.com.
[6] R. Munakata, CubeSat Design Specification (Rev.11). California Polytechnic State University (CalPoly), San Luis Obispo, 2008.
[7] J. Schaffner, The Electronic System Design, Analysis, Integration, and Construction of the CalPoly State University CP1 CubeSat. 16th Conference on Small Satellites, San LuisObispo, August 2002.
[8] List of CubeSat Missions and their status: http://mtech.dk/thomsen/space/cubesat.php.
[9] J. Puig-Suari, C. Turner and W. Ahlgren, Development of the Standard CubeSat Dep-loyer and a CubeSat Class PicoSatellite. California Polytechnic State University, San Luis Obispo, 2001.
[10] J.C. Juang and J.J. Miau, Overview of the PACE Satellite: a Three-Axis Stabilized
CubeSat. 1st International CubeSat Symposium, San Luis Obispo, 2003.
[11] J.K. Tu, S.H. Wu and C.C Chu, Platform for Attitude Control Experiment (PACE): An Experimental Three-Axis Stabilized CubeSat. 18th AIAA/USU Conference on Small Satellites, 2004.
[12] T. Sarafin, Spacecraft Structures and Mechanism. Kluwer Academic Publishers, 1995.
[13] Innovative Solutions In Space: http://www.isispace.nl.
[14] University of Leicester CubeSat project (PLUME): http://cubesat.wikidot.com
[15] P. Panetta, NASA/GSFC Nano-Satellite Technology Development. NASA-GSFC, Ma-ryland, 2003.
[16] C. McNutt, Modular Nanosatellite – (Plug-and-Play) PnPCubeSat. 7th Responsive Space Conference, AIAA, Los Angeles, April 2009.
[17] J. Phelan, Polysat CPX Modular Picosatellite Structural System. CalPoly, San Luis Obispo, March 2007.
[18] J. Wijker, Spacecraft Structures. Springer, 2008.
[19] National Research Council, Technology for Small Spacecraft. National Academy Press, Washington D.C., 1994.
[20] P. Fortescue and J. Stark, Spacecraft Systems Engineering 2nd Edition. Wiley, 1995.
[21] V. Pisacane, Fundamentals of Space Systems 2nd Edition. Oxford University Press, 2005.
[22] T. Doering, Development of a Reusable CubeSat Satellite Bus Architecture for the Kysat-1 Spacecraft. Master thesis, University of Kentucky, 2009.
[23] P. Christensen and A. Klarbring, An Introduction to Structural Optimization, Springer, 2009.
[24] W. Spillers and K. MacBain, Structural Optimization. Springer, 2009.
[25] R. Budynas, Advanced Strength and Applied Stress Analysis. McGraw-Hill, 1977.
[26] R. Cook, Concepts and Application of Finite Element Analysis 4th Edition. Wiley, 2001.
[27] H.H. Lee, ANSYS 12.0 course. Engineering Science Department, NCKU, 2009.
[28] A. Scholz, PACE Qualification Vibration Test Specification. NCKU, 2009.
[29] R. Fleeter, Micro Space Craft. The Edge City Press, 1995.
[30] MatWeb, Material Property Data: http://www.matweb.com
[31] C. Jenkins and S. Khanna, Mechanics of Materials: A Modern Integration of Mechan-ics and Materials in Structural Design. Academic Press Inc, 2005.
[32] G. Upadhyaya and A. Upadhyaya, Materials Science and Engineering. Anshan, UK, 2007.
[33] AIAA Aerospace Design Engineers Guide (5th Edition). AIAA, September 2003.