Air table experiment system for testing nano-satellite end-of-mission reorbiting device

该实验方案的目标是设计一个空气台实验系统，能够在模拟失重空间环境中测试纳卫星使命结束离轨装置的系绳展开机构。 纳米卫星使命终止脱轨器是利用电动系绳（EDT）阻力使纳米卫星脱轨的小型装置。由于它利用与地球磁场的被动电磁相互作用来降低航天器的轨道，因此它既不需要推进剂也不需要动力。因此，它能够以非常低的质量要求实现纳米卫星的自主脱轨。随着世界各地越来越多的大学能够为他们的教育计划发射纳米卫星，未来的发射器必须将使命结束的纳米卫星从太空中移除，以保护航天器免受空间碎片的影响。自1992年以来，EDT已经进行了多次演示飞行。然而，由于工程问题，许多过早失败，包括最近的MAST使命在2007年4月，其中系绳未能部署。EDT系统遇到的关键工程问题包括：（1）系绳部署，以及（2）系绳系统的稳定性。系绳将通过使用弹簧力或其他机械装置从主卫星排出的端部质量来展开。弹簧力不足会因系统阻尼而导致部署失败，而弹簧力过大如果没有适当的控制，可能会使系绳松弛或受阻，导致系绳反冲或端部质量反弹，危及主机。拟议的研究计划将通过开发和测试一个高度可靠的EDT系统来解决工程问题，该系统使用空气台来模拟失重的空间环境。发现现有理论中可能忽略的一些基本问题，将有助于对纳卫星使命结束离轨装置的设计提供见解。拟议的设备将在实验设计、先进的测量和仪器方面对总部质量保证人员进行培训。该提案的结果将加强约克大学的空间工程计划。

The objective of this experimental program is to design an air table experiment system able to test the tether deployment mechanism of a nano-satellite end-of-mission deorbiting device in a simulated space environment of zero gravity.     Nano-satellite end-of-mission deorbitors are small devices that use electrodynamic tether (EDT) drag to deorbit a nano-satellite. Because it uses passive electromagnetic interactions with the Earth's magnetic field to lower the orbit of the spacecraft, it requires neither propellant nor power. Thus, it can achieve autonomous deorbit of a nano-satellite with very low mass requirements. As more and more universities around the world are able to launch nano-satellites for their educational programs, it is important for future launchers to remove the end-of-mission nano-satellites from space in order to safeguard spacecrafts from space debris. Several EDT demonstration missions have flown since 1992. However, many failed prematurely due to ENGINEERING problems including the most recent MAST mission in April 2007, where the tether failed to deploy. The critical engineering problems encountered by the EDT system include: (1) tether deployment, and (2) stability of the tether system. The tether will be deployed by the end mass expelled from the host satellite using either spring force or other mechanical means. Insufficient spring force will fail the deployment due to the system damping, while large spring force without proper control may slack or snag the tether, resulting in the tether recoil or the rebound of end mass to endanger the host. The proposed research program will address the engineering problems by developing and testing a highly reliable EDT system using an air table to simulate space environment of zero gravity. It will help in providing insights into the design of the nano-satellite end-of-mission deorbiting device to discover some fundamental issues which may be overlooked by existing theories. The proposed equipment will train HQPs in the design of experiments, advanced measurements and instruments. The outcome of the proposal will enhance the space engineering program at York University.