Dynamics and Control of Tethered Spacecraft Systems

系留航天器系统的动力学与控制

基本信息

批准号：
RGPIN-2018-05991
负责人：
Zhu, ZhengHong
金额：
$ 4.66万
依托单位：
York University
依托单位国家：
加拿大
项目类别：
Discovery Grants Program - Individual
财政年份：
2018
资助国家：
加拿大
起止时间：
2018-01-01 至 2019-12-31
项目状态：
已结题

来源：
https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=669907
关键词：
Dynamics Control Tethered Spacecraft Systems

项目摘要

Tethered Spacecraft Systems (TSS) are novel devices to extend the capability of spacecraft to conduct scientific and other tasks. Among them, the propellantless propulsion by electrodynamic tethers in Earth orbits or electrostatic tethers beyond Earth orbits is an appealing alternative to existing rocket propulsion. However, TSS are difficult to operate due to their extreme long length and variable configurations. As such, a thorough understanding of dynamics and control of TSS is a preoccupation for any successful TSS mission.******High-fidelity modeling of TSS inevitably leads to a set of nonlinear, distributed and coupled partial differential equations. The control of such systems subject to stochastic perturbative effects requires feedback of states. However, interior states along tether length are not measurable as sensors are only available at spacecraft connected at tether ends. This leads to a challenging feedback control for distributed systems with only boundary observation. Furthermore, the implementation and validation of control laws for TSS before launch are equally challenging. Novel ground test facility and theory are required to scale down the real TSS into testbeds with limited dimensions.******The aim of this discovery program is to systematically study fundamentals of dynamics and control of TSS in and beyond Earth orbits. Builds on the success of previous Discovery Grant, new computational control for flexible TSS will be developed by considering multiphysics, coupled rigid-flexible dynamics, orbital perturbations, and boundary feedback control with limited observation at boundary. First, a new nodal position finite element Kalman filter will be developed to give spatial and temporal estimates of interior states (motion and electric voltage) along tether length based on feedback at tether's ends. Second, a novel computational control without explicit structures for TSS will be developed by combining a dual adaptive model predictive control with the nodal position finite element Kalman filter. Third, the derived computational control will be used for tether deployment/retrieval, effective and efficient space debris deorbit by electrodynamic tether, and interplanetary travel by electrical solar wind sail. Fourth, ground tests will be conducted to validate the proposed computational control. Finally, key components of TSS will be tested in microgravity by parabolic flights and prototype of electrodynamic tether deorbit device will be demonstrated in space.******The discovery program will train HQP in multi-physical modeling, coupled rigid-flexible dynamics, astrodynamics, advanced control theory, space environment, software, hardware, and experimental validation. HQP will also be trained in professional development through discussion with collaborators and team members, participation in real TSS space mission, and collaboration with space industry.**

束缚航天器系统（TSS）是扩展航天器执行科学和其他任务能力的新型设备。其中，地球轨道或地球轨道以外的地球轨道或静电束的电动动力的推进是在现有火箭推进的方向上的一种吸引人的替代方法。但是，由于TSS非常长，很难操作。因此，对TSS的动力学和控制的透彻理解是对任何成功的TSS任务的关注。****** TSS的高保真建模不可避免地会导致一组非线性，分布式和耦合的部分偏微分方程。对这种系统的控制受到随机扰动效应的控制需要状态反馈。但是，沿着系绳长度的内部状态无法测量，因为仅在连接的绳索末端连接的航天器上可用传感器。这导致对只有边界观察的分布式系统的有挑战性的反馈控制。此外，在发布之前对TSS的控制法实施和验证同样具有挑战性。需要新颖的地面测试设施和理论才能将实际TSS扩展到具有有限尺寸的测试床中。******该发现计划的目的是系统地研究地球轨道内外TSS的基本原理。建立在先前发现赠款的成功之上，将通过考虑多物理学，耦合的刚性动力学，轨道扰动和边界反馈控制，而在边界上有限观察，将开发灵活TSS的新计算控制。首先，将开发出一个新的节点位置有限元元素滤波器，以根据束缚的末端的反馈来对内部状态（运动和电压）的内部状态（运动和电压）进行空间和时间估计。其次，通过将双重自适应模型预测控制与节点位置有限元元素KALMAN滤波器相结合，将开发出具有TSS显式结构的新型计算控制。第三，派生的计算控制将用于系绳部署/检索，有效，有效的空间碎片碎片，通过电动力绳索以及通过电气太阳风帆进行行径际旅行。第四，将进行地面测试以验证提出的计算控制。最后，将通过抛物线飞行和电动力束缚DeOrbit设备的原型在微重力测试中测试TSS的关键组件。 HQP还将通过与合作者和团队成员的讨论，参与真正的TSS太空任务以及与太空行业的合作进行讨论。**