Abstract The Earth Space Elevator is an ingenious concept aimed at providing easy access to space, eliminating the need for rockets and potentially reducing drastically the launch costs. Technical advancements that could make the Space Elevator possible, among others, would be the availability of long carbon nanotubes or other super-strong and light material. This paper aims at addressing issues related with the stability of the system when the elevator is partially deployed starting from a nucleus in geostationary orbit (GEO). As noted by various authors, the energy increase needed to keep the orbital centre (where the gravity and centrifugal forces balance out) at GEO altitude during deployment while the tether is lengthened leads to an orbit with a positive orbital energy, i.e., the circular orbit has an energy level pertaining to a hyperbolic orbit. This situation leads to the instability of the unanchored system that would tend to escape from the geostationary orbit. The paper illustrates the change in orbital energy during assembly for a system made of a cylindrical tether and then investigate the stability of the coupled orbital and attitude motion in the orbital plane before anchoring. The analysis leads to the conclusion that the orbital motion instability ensues well before the orbital energy of the unperturbed system becomes positive.

中文翻译：

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部分部署的地球空间电梯的能量和轨道稳定性

摘要 地球太空电梯是一个巧妙的概念，旨在提供进入太空的便利，消除对火箭的需求，并有可能大幅降低发射成本。可以使太空电梯成为可能的技术进步，其中包括长碳纳米管或其他超强和轻材料的可用性。本文旨在解决当电梯从地球静止轨道 (GEO) 中的一个核开始部分部署时与系统稳定性相关的问题。正如多位作者所指出的，在部署期间将轨道中心（重力和离心力平衡的地方）保持在 GEO 高度所需的能量增加，同时系绳被拉长导致轨道具有正轨道能量，即，圆形轨道的能级与双曲线轨道有关。这种情况导致非锚定系统的不稳定性，该系统倾向于脱离地球静止轨道。该论文说明了由圆柱系绳制成的系统在组装过程中轨道能量的变化，然后研究了锚定前轨道平面内耦合轨道和姿态运动的稳定性。分析得出的结论是，在未受扰动系统的轨道能量变为正值之前，轨道运动不稳定就发生了。该论文说明了由圆柱系绳制成的系统在组装过程中轨道能量的变化，然后研究了锚定前轨道平面内耦合轨道和姿态运动的稳定性。分析得出的结论是，在未受扰动系统的轨道能量变为正值之前，轨道运动不稳定就发生了。该论文说明了由圆柱系绳制成的系统在组装过程中轨道能量的变化，然后研究了锚定前轨道平面内耦合轨道和姿态运动的稳定性。分析得出的结论是，在未受扰动系统的轨道能量变为正值之前，轨道运动不稳定就发生了。