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281.
282.
文章介绍了空间碎片被动防护技术的主要技术路线及其三个核心研究内容,即风险评估、防护技术及超高速撞击试验,并对我国空间碎片被动防护技术体系的建设提出了一些初步建议。 相似文献
283.
空间碎片超高速撞击动力学建模与数值仿真技术 总被引:12,自引:0,他引:12
阐明了空间碎片超高速撞击数值仿真技术研究的目的、意义和国内外发展状况 ;重点论述了空间碎片超高速撞击数值仿真技术的主要研究内容、技术指标和具体实施途径 ,从而为研究的深入开展提供了技术依据和指导原则 相似文献
284.
带电粒子在材料中的剂量深度分布计算 总被引:4,自引:3,他引:1
航天器在轨道运行期间,会受到各种带电粒子的作用,其能量沉积在表面材料中,对表面材料的性能有较大的损伤。文章介绍了剂量深度计算程序,利用SRIM及ITS软件的计算结果,计算出了带电粒子在材料中的剂量深度分布,并对空间轨道实际环境下材料中的剂量深度分布进行了计算。利用这一程序,在“东四”热控涂层试验中进行了剂量深度分布拟合,计算了多种能量电子拟合试验下荆量深度分布与空间实际环境的比较,得出了相关的试验参数。 相似文献
285.
区域观察小卫星星座重构方法研究 总被引:1,自引:0,他引:1
在对地观测任务中,经过优化设计的卫星星座通常具有较强的适应能力。但是,当星座中某颗卫星失效或地面需求发生变化时,就需要进行星座重构,以恢复或增强对部分地区的观察能力。提出了小卫星区域观察组网的方法,重点探讨了在应急情况下区域观察小卫星星座的重构问题,研究了节省能量的卫星轨道机动方法,特别提出了保持轨道属性和星座基本构形的预置量机动方法,分析了应急机动星座重构的几种情况,给出了每种情况的星座重构策略。 相似文献
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287.
Michael C.F. Bazzocchi Juan Miguel Sánchez-Lozano Houman Hakima 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(3):1155-1173
As private companies and government space agencies begin to seriously consider the task of active space debris removal, it is becoming increasingly more important to determine the highest priority objects to deorbit. This work sets forth an approach for prioritization of space debris through the utilization of Multi-Criteria Decision-Making methodologies and fuzzy logic, as well as both quantitative and qualitative criteria. The proposed debris prioritization approach considers various criteria including the orbit, size, mass, pairwise and total collision probabilities, and decay timeframe of each debris object. The means of assigning attributes to each assessment criterion is discussed in detail. To determine the weighting scheme for the criteria, a questionnaire was prepared and shared with experts in the field of space situational awareness. The work examines over two thousand critical debris objects selected from the existing debris catalog with respect to these criteria. The quantified attributes for each debris object are then aggregated through the fuzzy versions of the Analytic Hierarchy Process and the Technique for Order Preference by Similarity to Ideal Solution. The results of the analysis identify high-priority debris objects for removal from Earth-bound orbits. 相似文献
288.
Estrella Olmedo Noelia Sánchez-Ortiz Nuria Guijarro Jaime Nomen Holger Krag 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
In the framework of a potential European Space Situational Awareness System (ESSAS), we propose some optical strategies such that try to minimize the requirement of tracking measurements for the orbit determination computation when the catalogue is under construction. We will analyse them in terms of coverage, timeliness and orbit determination accuracy by means of the AS4 simulator (developed by Deimos Space S.L.U.). Moreover, observation campaigns have been performed from La Sagra Observatory in order to check the applicability of those strategies. These strategies are used for defining different choices for the future European Optical Space Surveillance System in the framework of the ESA contract no. 22738/09/D/HK. 相似文献
289.
Low earth orbit has become increasingly congested as the satellite population has grown over the past few decades, making orbital debris a major concern for the operational stability of space assets. This congestion was highlighted by the collision of the Iridium 33 and Cosmos 2251 satellites in 2009. This paper addresses the current state of orbital debris regulation in the United States and asks what might be done through policy change to mitigate risks in the orbital debris environment. A brief discussion of the nature of orbital debris addresses the major contributing factors including size classes, locations of population concentrations, projected satellite populations, and current challenges presented in using post-mission active debris removal to mitigate orbital debris. An overview of the current orbital debris regulatory structure of the United States reveals the fragmented nature of having six regulating bodies providing varying levels of oversight to their markets. A closer look into the regulatory policy of these agencies shows that, while they all take direction from The U.S. Government Orbital Debris Mitigation Standard Practices, this policy is a guideline with no real penalty for non-compliance. Various policy solutions to the orbital debris problem are presented, ranging from a business as usual approach to a consolidated regulation system which would encourage spacecraft operator compliance. The positive aspects of these options are presented as themes that would comprise an effective policy shift towards successful LEO conservation. Potential economic and physical limitations to this policy approach are also addressed. 相似文献
290.
地球静止卫星南北位置保持控制系统的选择 总被引:4,自引:2,他引:4
简述了地球静止卫星南北位置保持控制系统的要求,然后比较了化学推进和电推进控制系统的特点,并较具体地分析了几种典型的电火箭发动机的性能和发展水平。在此基础上提出了作者对地球静止卫星南北位置保持控制的选择原则和看法。 相似文献