Ground-Based Microgravity and Magnetic Simulation Facility for Dynamics and Control of Electrodynamic Tethers in Space

该实验计划的目标是设计和建造一个地面试验台，以模拟电动系绳（EDT）在太空中将经历的微重力和磁场。它由一个亥姆霍兹保持架承载一个5自由度的空气轴承航天器系统。笼内的磁场是可控的，以抵消当地的地球磁场，并产生一个随时间变化的磁场，以模拟EDT在太空中跨越地球磁场。这将使我们能够观察EDT与地球磁场的相互作用，并验证地球上的EDT稳定性控制策略/法律。五自由度气浮航天器系统由花岗岩平台和带有EDT的五自由度气浮航天器模拟器组成。模拟器漂浮在适合亥姆霍兹笼内的桌子上。该试验台能够研究EDT的电动力学行为及其对地面控制动作的响应。这个高度集中的实验项目将为理解EDT的电磁相互作用，微重力下柔性系绳的动力学以及这些高度非线性，多物理耦合和欠驱动柔性系统的苛刻控制问题开辟一个新的窗口。由于空间验证/测试的成本过高，拟议的地面试验台将在实验室模拟空间环境中提供一个具有成本效益的测试设施，并揭示了在动态分析和控制律设计中遇到的复杂问题。这将使我们能够发现一些在正常情况下可能被现有理论忽视的基本问题。电动系绳技术在空间具有很大的潜力，例如清除空间碎片和用于行星际探索的电动太阳帆。拟议的设备将培训11名HQP。所有HQP将接受与电磁相互作用、多体动力学和控制理论、机械设计、加工和集成、电子硬件、无线通信、软件编程、数据采集和处理、评估系统性能的测试程序的设计和实施以及操作程序开发相关的多方面技术培训。它将提供一个类似太空的环境，培训HQP开发卫星有效载荷和仪器。这些实践经验和实际技能也将使HQP在就业市场上更具竞争力。

The objective of this experimental program is to design and build a ground testbed to simulate microgravity and magnetic field that an electrodynamic tether (EDT) will experience in space. It consists of a Helmholtz cage hosting a 5-DOF air-bearing spacecraft system. The magnetic field inside the cage is controllable to cancel the local Earth’s magnetic field and generate a time-varying magnetic field to simulate EDTs in space across Earth’s magnetic field. This will allow us to observe the EDT interaction with Earth’s magnetic field and validate EDT stability control strategy/law on Earth. The 5-DOF air-bearing spacecraft system consists of a granite table and a 5-DOF air-bearing spacecraft simulator that carries an EDT. The simulator float on the table that fit inside the Helmholtz cage. The testbed is capable of investigating the electrodynamic behaviors of EDTs and their responses to control actions on Earth. This highly focused experimental program will open up a new window to understand the electromagnetic interaction of EDTs, the dynamics of flexible tether in microgravity and the demanding control problems of these highly nonlinear, multi-physics coupled and under-actuated flexible systems. Due to the prohibitive cost for validation/testing in space, the proposed ground testbed will provide a cost-effective testing facility in an emulated space environment in lab and shed light into the complex problems encountered in the dynamic analysis and control law design. This will allow us to discover some fundamental issues that may be overlooked by existing theories in normal conditions. The electrodynamic tether technology has a great potential in space, for instance, the removal of space debris and the electric solar sail for interplanetary exploration. The proposed equipment will train 11 HQP. All HQP will be trained in multiple facets of technologies relating to electromagnetic interaction, multi-body dynamics and control theory, mechanical design, machining and integration, electronic hardware, wireless communication, software programming, data acquisition and processing, design and implementation of a testing procedure evaluating the performance of the system and development of operational procedures. It will provide a space-like environment to train HQP for the development of satellite payloads and instruments. These hands-on experiences and practical skills will also make HQP more competitive in job market.