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This document presents the result of contract 'The study for the space debris mitigation (orbital analysis)', commissioned by NASDA. This report will provide useful information to the project to produce draft standard of space debris mitigation requirements., 本書は、宇宙開発事業団から委託された、委託業務計画書に基づき、研究を行った成果に関する報告書である。当受託業務は、スペースデブリ対策の一環として、スペースデブリの発生防止標準および設計基準の作成に必要な、軌道上の物体の軌道解析などの研究を行うことを目的としている。

This research project aims at acquisition of basic information on orbital dynamics that will be required in determining and performing mission through orbital analysis of various missions including interplanetary flights. The following subjects were studied in 1996FY. The outlines of the achievements were described. (1) Basic analysis of orbits near Lagrangian points was performed. When a mission to L1 and L2 points in the sun-earth system is considered, selection between a halo orbit with large size, and a Lissajous orbit with small size will become important, in conjunction with the satellite design. It was demonstrated that a halo orbit could easily be designed by starting from the linearized solutions near L1 and L2 points through numerical integration. (2) Higher order perturbation analysis of a Phobos rendezvous orbit was conducted. The effects of the eccentricity of 0.015 in the Phobos orbit were examined by adding the eccentricity to the simplified model. The effects of the oblateness of the Mars and the spherically nonsymmetric terms of the Phobos gravity were studied by the addition of an oblateness of 1.03 degree to the model. Though the relative inclination at the threshold of stability was lowered in comparison with the case of the simplified model, it was confirmed that the orbit would provide an observation platform which satisfies the intended purpose. (3) The mean element analysis of orbit around asteroids was made. The area where a frozen orbit can be obtained and conditions of the frozen orbit were studied., 本研究プロジェクトは、惑星間飛行を含む種々のミッションの軌道解析を通してミッションの決定と遂行に必要な軌道力学に関する基本的な情報の収集を目的としている。1996年度は、以下の主題について研究した。(1)ラグランジュ点近傍軌道の基礎解析を行った。太陽-地球系のL1とL2点への飛行を考える場合には、人工衛星の設計に関連して大径のハロー軌道と小径のリサジュ軌道の選択が重要になる。ハロー軌道は、数値積分によりL1およびL2点近くの線形化解から出発して数値積分により容易に設計可能であることを示した。(2)フォボス・ランデブ軌道の高次摂動解析を行った。単純化モデルに離心率を加えることにより、フォボス軌道の離心率0.015の効果を試験した。フォボス軌道の傾角の効果は、モデルに1.03度の傾きを加えることにより試験した。火星の偏平揺動効果およびフォボス重力の非球対称項の影響も検討した。安定性の限界の相対的傾斜角については単純化モデルのケースに比較して低下するが、軌道は意図している目的を満足する観測軌道を提供する。(3)小惑星周回軌道の平均要素解析を行った。凍結軌道が得られる領域、凍結軌道の条件を検討した。

After the successful launch and operation of UWE-3 in 2013, UWE-4 is the next picosatellite in the University of Würzburg Experimental satellite program. UWE-4 is first from its series to have integrated propulsion system and with a mission objective to demonstrate attitude and orbit control using the miniature propulsion system. In future, this will pave the way to perform complicated missions such as formation flying using picosatellites. Major challenge in UWE-4 is the integration of the propulsion system (which includes both thrusters and power processing unit) into the 1U CubeSat. Integrating the thruster into the Picosatellite has several constraints, few include accommodation of the system within the structure at minimum mass and volume impact, structural design to withstand the critical launch conditions.In the scope of this master thesis project, the design of UWE-3 system arrangement is studied and the regions of possible integration of thruster units are identified. The two propulsion systems considered for the UWE-4 mission are the Micro Vacuum Arc Thrusters (µVAT) developed at UniBW in Munich, Germany and the NanoFEEP (highly miniaturized Field Emission Electric Propulsion) thrusters developed at TUDresden, Germany. During design phase, different concepts are created for the CubeSat rails to integrate the thrusters and the concepts are validated against the functional requirements as well as the CubeSat design specifications. Detailed CAD designs are completed for UWE-4 satellite using SolidWorks 2014. To validate the structural design, the CAD models are then subjected to Finite Element Modeling and Analysis (structural and thermal) using Siemens NX CAE. During static Structural analysis, various loading conditions and constraints are identified and applied to the system. Later NX NASTRAN solver is used to study and simulate the impact on the UWE-4 model. Also modal analysis was performed to study the natural frequencies of the system. With the motivat, Validerat; 20150709 (global_studentproject_submitter)