深空探测磁动力技术研究进展

开展深空探测对人类研究宇宙起源与发展、生命存在与进化等重大科学问题具有重要的意义。深空探测有很多关键技术有待突破,先进推进技术是其中最为重要的一个。而可用于深空探测的无需携带推进剂的磁动力推进技术,是利用太阳系和宇宙中广泛存在的等离子体流,使探测器所携带的低密度超导材料制作的线圈通电,在探测器周围形成一个磁场区域,通过该磁场与太阳风等离子流相互作用产生推动力的一种先进技术。文章介绍了磁动力技术的国内外发展现状、磁帆与等离子体流增强型磁帆的基本原理、技术特点以及在未来深空探测中的潜在应用,为我国未来深空探测任务的工程实施提供一种新的方法。     

磁等离子体推力器工作机理与应用前景研究

研究了发动机能量输入、工质电离、等离子体加速及能量转换过程及机理,同时分析了磁等离子体推力器在空间推进任务中的应用前景.研究表明磁等离子体推力器主要利用电磁力加速和磁喷管的能量转换作用来实现加速,这种方式在大功率条件下,能够获得大推力、高功率和较长工作时间,在大功率轨道航天器和深空任务中有广阔的应用前景.     

面向深空任务的电磁桨推力器设计

为解决深空任务需要大量推进工质的问题,提出了一种电磁桨推力器的概念,以恒星际等离子体为工质,利用带电粒子在正交匀强电场和磁场中的电漂移效应,产生对航天器的推力。根据带电粒子的漂移速度,分非相对论和相对论两种情况,推导了电磁桨推力器的推力公式,分析了电磁桨推力器的设计约束条件,并针对星际航行和无拖曳控制任务,结合实际工程技术水平,设计了初步电磁桨推力器方案和试验验证方案。计算结果表明,使用上述电磁桨推力器方案的航天器无需携带任何工质,在星际航行中每年可以得到1056m/s速度增量。     

大功率无电极高密度等离子体电磁推进概述

无电极高密度等离子体电磁推进技术已成为未来深空探测、载人航天和货运、太阳能电站以及航天器在轨服务与维护等空间任务中极具竞争力的核心推进技术之一。在梳理不同无电极等离子体电磁加速机制基础上,开展大功率无电极高密度等离子体电磁推进技术性能对比,给出新概念无电极场反构型电磁推进技术向未来超大功率拓展的优势和发展潜力,同步分析了该技术亟需解决的关键基础问题,旨在为中国新概念场反构型电磁推进技术的研发提供理论基础。     

深空探测推进技术发展趋势

推进技术是制约深空探测能力的重要因素,由于深空探测航天器自身特点和任务需求的多样性,对推进系统类型的要求也不尽相同,需要在推力、比冲、功率、重量等关键指标选择方面进行综合衡量。对当前和未来适用于深空探测任务需求的几种典型空间推进技术的发展情况进行了阐述,包括混合模式推进技术、太阳能电推进技术、空间核电推进技术、帆类推进技术等,介绍了这些技术的研究进展和应用情况,并对后续应用进行了展望,为我国深空探测推进技术发展提供参考。     

低轨航天器磁推进及其能力估算

针对地球空间磁场分布特点,提出可用于实现低轨航天器轨道维持、轨道变更的无质消耗推进技术。从基本的磁学理论出发,建立了带磁航天器在地球空间磁场中的飞行磁推力模型,阐述了通过航天器磁性获取无工质消耗连续推力的磁推进概念和原理,阐明了作用机理,提出了磁力矩解耦的磁力线追踪推力策略,给出了磁推进的能力包络和轨道高度保持与提升的典型估算结果。分析表明,当飞行体磁矩达到10⁶Am²量级以上时,可以有效用于600~1000km范围内轨道高度保持或提升。此外,文章还简要分析了实现高磁矩的技术可行性。     

发扬创新精神 发展离子推进

发扬创新精神发展离子推进朱毅麟（中国空间技术研究院）１电推进登上应用舞台□□电推进具有比冲高、推力小、重量轻、体积小、消耗工质少和需要一定量电功率等特点。本世纪六七十年代,电热、静电和电磁三类电推进器都陆续研制成功,并进行过多次空间飞行试验和试用。但...     

VASIMR中螺旋波等离子体源设计

螺旋波等离子体具有密度高,可控性强且无电极等优点,被应用于可变比冲磁等离子体火箭(VASIMR,Variable Specific Impulse Magnetoplasma Rocket)中.设计了一个螺旋波等离子体源,并给出了其中2个关键部分——磁场线圈和螺旋波天线的设计.对螺旋波等离子体源进行了初步实验,结果表明,电子密度随射频输入功率的增加几乎呈线性上升,估计电子密度的量级在通入工质后完全可达10¹¹ cm^-3.     

近室温磁制冷工质选择的热力学准则

对近年来在制冷界研究相当活跃的磁制冷的工质，尤其是近室温磁制冷的工质－铁磁材料，在外加磁场中的热力学特性进行了分析、讨论，并在此基础上总结了选取近室温磁制冷工质的理论依据和原则，使实际中的选择工作有了针对性，减少了盲目性。     

感应式脉冲等离子体推力器技术综述

摘要： 综合文献及作者研究实践,介绍了感应式脉冲等离子体推力器的原理和特点.从国外研究机构与项目、推力器组件和系统集成实验、工作机理数值仿真等方面,总结和评述了达到的技术状态与认识.最后梳理了面临的技术挑战,提出了可能的解决途径.     

连续小推力非开普勒悬浮轨道研究综述

连续小推力非开普勒悬浮轨道在深空探测与地球极地观测任务中有着重要的应用前景。归纳了电推进、太阳帆推进等连续小推力技术的发展历程与现状;阐述了日心、行星悬浮轨道的动力学特性、稳定性、轨道保持策略;分析了三体问题下人工拉格朗日点的优势及其在深空探测方面的应用;讨论了悬浮轨道编队飞行的研究方法与控制策略。最后针对小推力悬浮轨道研究发展面临的难题,提出了研究新思路和应用新方向。     

Systems design of a hybrid sail pole-sitter

This paper presents the preliminary systems design of a pole-sitter. This is a spacecraft that hovers over an Earth pole, creating a platform for full hemispheric observation of the polar regions, as well as direct-link telecommunications. To provide the necessary thrust, a hybrid propulsion system combines a solar sail with a more mature solar electric propulsion (SEP) thruster. Previous work by the authors showed that the combination of the two allows lower propellant mass fractions, at the cost of increased system complexity. This paper compares the pure SEP spacecraft with the hybrid spacecraft in terms of the launch mass necessary to deliver a certain payload for a given mission duration. A mass budget is proposed, and the conditions investigated under which the hybrid sail saves on the initial spacecraft initial mass. It is found that the hybrid spacecraft with near- to mid-term sail technology has a lower initial mass than the SEP case if the mission duration is 7 years or more, with greater benefits for longer duration missions. The hybrid spacecraft with far-term sail technology outperforms the pure SEP case even for short missions.     

Status of solar sail technology within NASA

In the early 2000s, NASA made substantial progress in the development of solar sail propulsion systems for use in robotic science and exploration of the solar system. Two different 20-m solar sail systems were produced. NASA has successfully completed functional vacuum testing in their Glenn Research Center’s Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by Alliant Techsystems Space Systems and L’Garde, respectively. The sail systems consist of a central structure with four deployable booms that support each sail. These sail designs are robust enough for deployment in a one-atmosphere, one-gravity environment and are scalable to much larger solar sails – perhaps as large as 150 m on a side. Computation modeling and analytical simulations were performed in order to assess the scalability of the technology to the larger sizes that are required to implement the first generation of missions using solar sails. Furthermore, life and space environmental effects testing of sail and component materials was also conducted.     

Extrasolar space exploration by a solar sail accelerated via thermal desorption of coating

For extrasolar space exploration it might be very convenient to take advantage of space environmental effects such as solar radiation heating to accelerate a solar sail coated by materials that undergo thermal desorption at a particular temperature. Thermal desorption can provide additional thrust as heating liberates atoms, embedded on the surface of the solar sail. We are considering orbital dynamics of a solar sail coated with materials that undergo thermal desorption at a specific temperature, as a result of heating by solar radiation at a particular heliocentric distance, and focus on two scenarios that only differ in the way the sail approaches the Sun. For each scenario once the perihelion is reached, the sail coat undergoes thermal desorption. When the desorption process ends, the sail then escapes the Solar System having the conventional acceleration due to solar radiation pressure. We study the dependence of a cruise speed of a solar sail on perihelion of the orbit where the solar sail is deployed. The following scenarios are considered and analyzed: (1) Hohmann transfer plus thermal desorption. In this scenario the sail would be carried as a payload to the perihelion with a conventional propulsion system by a Hohmann transfer from Earth’s orbit to an orbit very close to the Sun and then be deployed. Our calculations show that the cruise speed of the solar sail varies from 173?km/s to 325?km/s that corresponds to perihelion 0.3?AU and 0.1 AU, respectively. (2) Elliptical transfer plus Slingshot plus thermal desorption. In this scenario the transfer occurs from Earth’s orbit to Jupiter’s orbit; then a Jupiter’s fly-by leads to the orbit close to the Sun, where the sail is deployed and thermal desorption comes active. In this case the cruise speed of the solar sail varies from 187?km/s to 331?km/s depending on the perihelion of the orbit. Our study analyses and compares the different scenarios in which thermal desorption comes beside traditional propulsion systems for extrasolar space exploration.     

Solar sail science mission applications and advancement

Solar sailing has long been envisaged as an enabling or disruptive technology. The promise of open-ended missions allows consideration of radically new trajectories and the delivery of spacecraft to previously unreachable or unsustainable observation outposts. A mission catalogue is presented of an extensive range of potential solar sail applications, allowing identification of the key features of missions which are enabled, or significantly enhance, through solar sail propulsion. Through these considerations a solar sail application-pull technology development roadmap is established, using each mission as a technology stepping-stone to the next.     

A scalable bus-based attitude control system for Solar Sails

Recently, there has been a renewed interest in Solar Sails as an alternative means of space propulsion. Many different attitude control systems have been designed for Solar Sails taking advantage of the centre-of-mass (CM)/centre-of-pressure (CP) offset while utilising the main sail structure to position the actuators. However, by attaching actuators to the main sail, these systems increase the risks involved in the deployment subsystem.     

Paths not taken – The Gossamer roadmap’s other options

Highly efficient low-thrust propulsion is increasingly applied beyond commercial use, also in mainstream and flagship science missions, in combination with gravity assist propulsion. Another recent development is the growth of small spacecraft solutions, not in size but in numbers and individual capabilities.Just over ten years ago, the DLR-ESTEC Gossamer Roadmap to Solar Sailing was set up to guide technology developments towards a propellant-less and highly efficient class of spacecraft for solar system exploration and applications missions: small spacecraft solar sails designed for carefree handling and equipped with carried application modules.Soon, in three dedicated Gossamer Roadmap Science Working Groups it initiated studies of missions uniquely feasible with solar sails such as Displaced L₁ (DL1) space weather advance warning and monitoring, Solar Polar Orbiter (SPO) delivery to very high inclination heliocentric orbit, and multiple Near-Earth Asteroid (NEA) rendezvous (MNR). Together, they demonstrate the capability of near-term solar sails to achieve at least in the inner solar system almost any kind of heliocentric orbit within 10 years, from the Earth-co-orbital to the extremely inclined, eccentric and even retrograde. Noted as part of the MNR study, sail-propelled head-on retrograde kinetic impactors (RKI) go to this extreme to achieve the highest possible specific kinetic energy for the deflection of hazardous asteroids.At DLR, the experience gained in the development of deployable membrane structures leading up to the successful ground deployment test of a (20 m)², i.e., 20 m by 20 m square solar sail at DLR Cologne in 1999 was revitalized and directed towards a 3-step small spacecraft development line from as-soon-as-possible sail deployment demonstration (Gossamer-1) via in-flight evaluation of sail attitude control actuators (Gossamer-2) to an envisaged proving-the-principle flight in the Earth-Moon system (Gossamer-3). First, it turned the concept of solar sail deployment on its head by introducing four separable Boom Sail Deployment Units (BSDU) to be discarded after deployment, enabling lightweight 3-axis stabilized sailcraft. By 2015, this effort culminated in the ground-qualified technology of the DLR Gossamer-1 deployment demonstrator Engineering Qualification Model (EQM). For mission types using separable payloads, such as SPO, MNR and RKI, design concepts can be derived from the BSDU characteristic of DLR Gossamer solar sail technology which share elements with the separation systems of asteroid nanolanders like MASCOT. These nano-spacecraft are an ideal match for solar sails in micro-spacecraft format whose launch configurations are compatible with ESPA and ASAP secondary payload platforms.Like any roadmap, this one contained much more than the planned route from departure to destination and the much shorter distance actually travelled. It is full of lanes, narrow and wide, detours and shortcuts, options and decision branches. Some became the path taken on which we previously reported. More were explored along the originally planned path or as new sidings in search of better options when circumstance changed and the project had to take another turn. But none were dead ends, they just faced the inevitable changes when roadmaps face realities and they were no longer part of the road ahead. To us, they were valuable lessons learned or options up our sleeves. But for future sailors they may be on their road ahead.     

激光烧蚀微推进技术研究现状及展望

激光烧蚀微推进技术是空间微推进技术中的一种,是基于激光推进原理的电推进技术,可用于微纳卫星姿态与轨道控制.回顾激光烧蚀微推进技术发展的历程,简述其推进原理涉及的基本理论,对激光烧蚀微推进领域涉及的技术方向研究现状进行探讨,对相关各种类型微推力器进行对比分析,结合激光烧蚀微推进技术的特点,分析激光烧蚀微推进技术发展趋势,并给出了发展建议.