高面质比航天器轨道运动的表征

With the advent of “smart dust”, Chip Satellites, and Inflatable Satellites, ,The so-called High Area-to-Mass Spacecraft (HAMS) would be achieved when the ratio between the forces associated to its surface area and the forces related to its mass keeps increasing, such as “smart dust”, Chip Satellites, and Inflatable Satellites. Even for traditional spacecraft, the high ratio could be obtained by utilizing smaller mass while enlarging the surface area of such parts as solar sail, antenna..New features, that is, unsteady state, strong nonlinearity and non-Keper behaviors, are added to the dynamics of this kind of spacecraft. Although the scientific problem included in the topic, the characterization of orbital motion, could be described by Newtonian mechanics, the resulting orbital motion equations can be very complicated without the hypothesis of Kepler motion. .The current researches about the orbital dynamics for this spacecraft are very limited. Therefore, a novel description for the orbital motion of HAMS influenced by multiple force fields in geo-space is proposed in this investigation, which contributes to the precise modeling for the multi-source environment forces. Then, the forces are applied to act on the influenced space of six orbital elements, which is followed by a representation of novel orbital motion, which leads to the establishment of precise, simple and practical orbital dynamic model for HAMS..Analytic solutions are explored by combination of nonlinear mapping and regularization method. Furthermore, numeric simulations are used to demonstrate its validity. Enormous efforts would be paid to come up with novel orbital dynamic theory and modeling method for HAMS, laying foundations for the precise and on-line control.

随着“智能灰尘”、芯片卫星、充气卫星的出现，以及传统航天器的轻量化，太阳帆板、天线等部件面积的趋大化，航天器所受与面积相关的力和与质量相关的力之间的比值不断上升，出现了所谓的高面质比航天器。其飞行动力学表现出新的特点：非稳态性、强非线性和强非开普勒特征。其科学问题是其轨道运动虽仍可在牛顿力学框架下表征，却因其突破了开普勒运动的假设，导致轨道运动方程极其复杂。目前国内外对此类航天器的轨道动力学研究很少。本项目针对高面质比航天器在近地环境多力场作用下轨道运动的新型表征问题提出一类依赖于面质比的环境力表征参量，用于精确建立多源环境力模型；并作用于轨道六要素影响空间，建立一种新型轨道运动表征方法，得到准确、简洁、实用的轨道动力学模型；探索基于非线性映射和正规化理论的求解方法，并用数值方法验证其有效性。本项目将力求创新发展新型航天器轨道动力学理论与建模方法，为其精确和实时控制奠定基础。

本研究严格按照原计划进行。课题围绕高面质比航天器，主要开展了基于高面质比航天器的非开普勒轨道设计和协同编队飞行动力学与控制理论研究、地月系统中太阳帆航天器的轨道动力学与控制理论研究和面向芯片级航天器的高面质比智能太阳帆主动驱动结构设计等方面的研究工作，具体包括：（1）以两类非开普勒轨道附近的航天器编队飞行为任务背景，系统深入地研究了日心悬浮轨道和平动点轨道周围航天器相对运动的动力学与制问题；针对太阳帆、电动帆等利用自然力作为推进方式的新型航天器，分析了其在非开普勒轨道设计及多颗航天器协同编队飞行中的潜在应用。（2）以地月轨道转移和月球探测任务为背景，分析了地球-月球-太阳帆系统的非自治特性以及地月空间的复杂显著的摄动环境，研究了地月系统中太阳帆的动力学机理与相应的控制方法。（3）以高面质比太阳帆智能主动结构为对象，提出了一种基于微机电系统加工技术的高面质比主动驱动结构的设计，完成了原理样机的研制、测试和改进，初步验证了针对高面质比航天器或太阳帆航天器的结构模型假设的合理性。其中，针对高面质比航天器的非开普勒轨道提出了新的描述方法，并研究了其协同编队飞行动力学与控制理论；基于高面质比航天器在地月轨道转移过程中的自然摄动力提出了全新的轨道设计和控制方法；突破传统高面质比帆面的设计思维，从硬件的角度提出了一种可以显著提高太阳帆面质比的设计、加工和控制方法。此外，本课题还进一步拓展研究了基于大型高面质比航天器平台的空间机器人的相关控制理论，以探索高面质比航天器的应用前景，并提供相关技术储备。