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Nathan R. Boone Robert A. Bettinger 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2021,67(8):2319-2332
The theoretical analysis of the motion of natural space debris near the stable Earth-Moon Lagrange Points, and , is presented with a focus on the potential debris risks to spacecraft operating near these points. Specifically, the research formulates a debris propagation model using four-body dynamics, then applies candidate probabilistic survivability models to a notional spacecraft operating at the and Lagrange points to quantify the collision risks to the spacecraft from natural debris particles. Of the survivability models implemented, the natural debris collision risks to spacecraft survivability are found to be incredibly low, but mitigation strategies to reduce the risk further are identified in this study. Overall, research into stable Lagrange point natural debris propagation improves understanding of the collision risks posed by the naturally occurring Kordylewski clouds and enhances operational planning for Lagrange point space missions. 相似文献
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针对航天器抓捕后由于系统质量特性和动量的改变而导致复合体系统失稳的问题,提出了两种基于角动量守恒的协调控制方法:关节阻尼控制和关节函数参数化协调控制。这两种方法通过对各关节和飞轮的速度进行协调规划和控制,实现对系统角动量的管理和重分配,在实现对目标进行停靠的同时,保证了基座的稳定性。两种方法各有优缺点,其中,关节函数参数化在实现系统稳定的同时还可使机械臂处于期望的臂型,以方便开展在轨维修等服务操作。所提出的方法将实际飞轮作为动量交换装置,具有很好的工程可实现性。仿真结果验证了方法的有效性。 相似文献
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为研究锦纶材料在长寿命在轨航天器中的环境适应性,提出了锦纶材料在空间环境使用的空间环境适应性评价指标,设计并实施了空间环境适应性评价试验。试验结果表明,锦纶材料在燃烧性能、逸出有害气体、真空质损和可凝挥发物、抗菌防霉、耐受交变温度、电离辐射中表现出友好的环境适应性。锦纶材料在受到空间环境中原子氧、紫外辐射作用时断裂强力明显下降,且原子氧与紫外辐照协同效果对锦纶材料的力学性能破坏具有加强效果。锦纶材料可作为空间舱内环境长期使用材料,在舱外环境使用时,需要特别考虑其力学特性受到原子氧、紫外辐照的影响。 相似文献
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P.A. Chaizy T.G. DimbylowP.M. Allan M.A. Hapgood 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
In this paper, Science Operations Planning Expertise (SOPE) is defined as the expertise that is held by people who have the two following qualities. First they have both theoretical and practical experience in operations planning, in general, and in space science operations planning in particular. Second, they can be used, on request and at least, to provide with advice the teams that design and implement science operations systems in order to optimise the performance and productivity of the mission. However, the relevance and use of such SOPE early on during the Mission Design Phase (MDP) is not sufficiently recognised. As a result, science operations planning is often neglected or poorly assessed during the mission definition phases. This can result in mission architectures that are not optimum in terms of cost and scientific returns, particularly for missions that require a significant amount of science operations planning. Consequently, science operations planning difficulties and cost underestimations are often realised only when it is too late to design and implement the most appropriate solutions. In addition, higher costs can potentially reduce both the number of new missions and the chances of existing ones to be extended. Moreover, the quality, and subsequently efficiency, of SOPE can vary greatly. This is why we also believe that the best possible type of SOPE requires a structure similar to the ones of existing bodies of expertise dedicated to the data processing such as the International Planetary Data Alliance (IPDA), the Space Physics Archive Search and Extract (SPASE) or the Planetary Data System (PDS). Indeed, this is the only way of efficiently identifying science operations planning issues and their solutions as well as of keeping track of them in order to apply them to new missions. Therefore, this paper advocates for the need to allocate resources in order to both optimise the use of SOPE early on during the MDP and to perform, at least, a feasibility study of such a more structured SOPE. 相似文献
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