Abstract The Electrodynamic Tether Technology for Passive Consumable-less Deorbit Kit (E.T.PACK) is a project aimed at the development of a deorbit kit based on low-work-function Tether (LWT) technology, i.e., a fully passive and electrically floating system made of a long conductive tape coated with a low-work-function material. The LWT interacts passively with the environment (ambient plasma, magnetic field, and solar radiation) to exchange momentum with the planet's magnetosphere, thus enabling the spacecraft to de-orbit and/or re-boost without the need for consumables. The main goal is to develop a deorbit kit and related software with Technology Readiness Level 4 and promote a follow-up project to carry out an in-orbit experiment. The planned kit in the experiment has three modes of operation: fully passive LWT and conventional electrodynamic tether equipped with an active electron emitter in passive and active modes. Several activities of the project pivot around the C 12 A 7 : e − electride, which will be used in four hardware elements: (i) LWT (ii) hollow cathode, (iii) photo-enhanced thermionic emission device to convert solar photon energy into electrical energy, and (iv) a hollow cathode thruster. These elements, some of which do not belong to the deorbit kit, are synergetic with the main stream of the project and common to some tether applications like in-orbit propulsion and energy generation. This work explains the activities of E.T.PACK and the approach for solving its technological challenges. After reviewing past progresses on electrodynamic tethers and thermionic materials, we present a preliminary concept of the kit for the in-orbit experiment, some simulation results, and the key hardware elements.

中文翻译：

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ETPACK 项目：迈向基于低功函数系绳技术的完全无源且无消耗的脱轨套件

摘要 The Electrodynamic Tether Technology for Passive Consumable-less Deorbit Kit (ETPACK) 是一项旨在开发基于低功函数 Tether (LWT) 技术的脱轨套件的项目，即由涂有低功函数材料的长导电胶带。LWT 与环境（环境等离子体、磁场和太阳辐射）被动相互作用，与行星的磁层交换动量，从而使航天器能够脱离轨道和/或重新加速，而无需消耗品。主要目标是开发技术准备4级的脱轨套件和相关软件，并推动后续项目进行在轨实验。实验中规划的试剂盒有三种操作模式：完全无源 LWT 和传统电动系绳，在无源和有源模式下配备有源电子发射器。该项目的几项活动围绕 C 12 A 7 : e - 电子，将用于四个硬件元素：(i) LWT (ii) 空心阴极，(iii) 用于转换太阳能光子能量的光增强热电子发射装置转化为电能，以及 (iv) 空心阴极推进器。这些元素（其中一些不属于脱轨套件）与项目的主流协同作用，并且在一些系链应用（如在轨推进和能源发电）中很常见。这项工作解释了 ETPACK 的活动以及解决其技术挑战的方法。在回顾过去在电动系绳和热离子材料方面的进展之后，