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1.
刘莹莹  周军  刘光辉  张佼龙  白博  李朋  黄河  刘睿 《宇航学报》2019,40(10):1115-1124
针对西北工业大学“翱翔”系列立方星在低成本、短周期、快响应的立方星技术方面的突破,介绍了应用于大气层外偏振导航技术试验的世界首颗12U立方星“翱翔之星”,世界首次组网开展低热层大气参数测量的QB50计划“翱翔一号”立方星等,总结了“翱翔”系列立方星的标准化结构设计、姿态控制系统、电源系统、星载计算机、通信与测控、部署器等核心系统的发展现状,介绍了自主研制的飞轮、磁力矩器、偏振敏感器载荷。并基于在轨组装,编队飞行,一箭多星等技术对“翱翔”系列立方星的应用进行了展望,对探索柔性、高精度、长寿命的立方星将有重要的意义。  相似文献   

2.
马卫华 《宇航学报》2020,41(7):860-867
本文对导弹/火箭制导、导航与控制(GNC)技术的发展进行了综述。总结归纳了不同阶段GNC关键技术的突破与跨越,重点对惯性导航、组合导航、摄动制导、闭路制导、迭代制导、频域设计、全数字设计、冗余控制、自适应控制等多项技术进行了总结和应用成果论述。对未来GNC技术的发展进行了思考与展望,并提出了七项关键技术。针对更聪明、更自主的弹/箭控制技术发展需求,提出并分析了"会学习"弹/箭的制导、导航与控制技术。  相似文献   

3.
Marcia S. Smith   《Space Policy》2011,27(1):20-23
The major features of President Obama’s new US space policy are discussed and particular aspects are compared with those of the previous Bush policy. In many cases there are similarities of substance but the tone of the latest policy is more outward looking and inclusive, with a far greater emphasis on cooperation, both internationally and with the private sector. And while some complain that the policy does not sufficiently emphasize US leadership, a statement by President Obama on the day of its release makes clear that this remains a paramount goal. Serious questions remain, however, about implementation of the new policy, particularly where it requires substantial government funding such as human spaceflight and the restructured weather/environmental satellite programs.  相似文献   

4.
Kevin Madders  Jan Wouters   《Space Policy》2003,19(1):155-46
Despite some impressive programmes, Europe has not yet succeeded in forging a coherent space policy and, as a result, has not achieved its full potential in this field. As efforts to formulate a more comprehensive policy intensify, a series of workshops has been initiated in order to provide an independent platform, allowing broad participation, for discussion of the issues. This article describes the rationale behind the process and the structure of the workshops and reports on the highlights of the first workshop, examining the fundamental questions involved. The themes of forthcoming workshops are also presented.  相似文献   

5.
长征运载火箭飞行控制技术的发展   总被引:1,自引:0,他引:1       下载免费PDF全文
宋征宇  潘豪  王聪  巩庆海 《宇航学报》2020,41(7):868-879
介绍了新一代长征运载火箭(LMLVs)的型谱,并从四个方面对运载火箭控制系统的发展进行了综述。制导技术从开环制导发展到迭代制导,并针对大推力直接入轨和终端姿态约束要求,进一步发展了迭代制导算法,入轨精度大幅提升;姿态控制仍以PID技术为基础,采用空间模态和等效摆角的建模方法解决助推飞行段多个舱段发动机联合摇摆问题,结合自抗扰技术(ARDC)进行主动减载控制;自载人航天工程起开展系统性的可靠性设计研究,逐渐形成了以设备冗余、算法容错和系统在线重构等为特点的技术体系,促进了长征火箭控制系统可靠性的整体提升;电子系统从分立的集中式体系架构,发展为集成化的分布式数字控制系统。针对当前飞行控制技术的研究热点,本文最后总结了长征运载火箭在这方面的最新实践与发展趋势。  相似文献   

6.
This report highlights the major conclusions and outcomes from a workshop held 28–29 June 2010 at Resources for the Future in Washington, DC, on methodological frontiers and new applications of valuing information and its social benefit. The participants provided answers to a series of questions: what is meant by “value of information”? When does information have value? What are state-of-the-practice methods to ascribe value to information? Participants also identified steps to ascribe, measure, and communicate value. The workshop included identification of five discrete approaches at the frontier of methodological advances: price- and cost-based derivation; Bayesian belief networks; regulatory cost-effectiveness evaluation; econometric modeling and estimation; and simulation modeling and estimation.  相似文献   

7.
Columba Peoples   《Space Policy》2010,26(4):205-208
Discussions of space security tend to recurrently return to the vexed issue of the ‘militarization’ and ‘weaponization’ of outer space. Debate over whether or not a sustainable definition can be maintained between these two concepts has been a feature of both academic and policy discourses, and has been particularly contentious with regard to new proposals for arms control in outer space. Yet, this paper argues, the militarization/weaponization debate fails to capture to vagaries of contemporary space policy with regard to understandings of ‘security’, and is in this sense an insufficient way of approaching the subject of space security in the first instance. Instead it is now more accurate to say that outer space is becoming ever more ‘securitized’: that is, access to space is now commonly framed as crucial to the military, economic and environmental security of leading states and international organizations.  相似文献   

8.
The rise of the EU as an actor in the European and world space theatres, in its various roles as initiator, owner and operator of large-scale programmes such as Galileo and GMES, has raised a number of questions with regard to industrial policy. Based on the experiences from the Galileo programme's procurement round in the Full Operational Capability (FOC) phase and on the present discussions on space industrial policy within the EU, this paper argues that, whereas the EU's political ambitions in space have been discussed and become reasonably well defined, the specific policy tools and legal instruments to put them into practice are far from complete. First, an unequivocal industrial policy for the space sector needs to be defined that reconciles the Union's political ambitions with the economic specificities of the space sector. At present, this is a work in progress, with opinions diverging between member states. Second, both logically and temporally, these policy decisions need to be translated into legal instruments that allow their implementation. This implies the development of made-to-measure funding instruments and procurement rules. We conclude by emphasising the need for a sector-specific industrial policy as an integral part of the EU's space policy.  相似文献   

9.
This article examines recent difficulties in the Russian space program through the analytic lens of the Russian political and economic reform effort. It argues that Russia’s problems go beyond a lack of financing. Instead, lack of investment and ‘brain drain’ have caused deep infrastructural problems which would take years of restored funding and political priority to fix. Russia’s continued activity in space stems almost solely from inertia left over from the Soviet period, and from funding provided by foreign partners anxious to exploit the cheap, sturdy elements of that Soviet legacy.  相似文献   

10.
杨彬  唐生勇  李爽  夏陈超 《宇航学报》2018,39(11):1197-1208
针对载人火星探测任务,结合我国现有技术基础,提出我国载人火星探测方案,重点研究载人火星探测任务推进系统的设计。首先,综合考虑载人深空探测任务的约束,采用Pork-Chop图设计了适用于不同任务场景的转移轨迹;然后,参考我国空间站技术,基于核热推进系统设计了我国载人火星探测任务的飞船;最后,对核热推进系统的发动机台数和推力进行了优化,得到了适用于不同任务场景的最优推进系统组合方案。本文所研究内容为我国未来载人火星探测任务提供了有益参考。  相似文献   

11.
Athough a poor nation with limited resources, India has spent large amounts of money on sophisticated space programme. It is pursuing a policy of using high technology to solve the country's social and economic problems, and at the same time to strengthen its international position. Satellite-aided communications, educational programmes, meteorology and resources survey and management are thus priority areas. This article examines the history and achievements of India's space programme, and considers the constraints faced and budget and staffing plans. Foreign policy and national security aspects are covered in detail, including the question of whether India's peaceful space policy can be put to military use.  相似文献   

12.
杨路易  李海阳  张进  周晚萌 《宇航学报》2019,40(12):1383-1392
针对载人登月任务中人货分运飞行模式,精确快速设计了着陆器(LM)的奔月轨道,分析了轨道窗口特性。以着陆器的奔月出发时刻、纬度幅角和加速脉冲为设计变量,基于多圆锥曲线法动力学模型,利用序列二次规划(SQP)优化算法对奔月轨道快速求解。在地心白道系下提出了近月点伪经度判别准则,该方法可为轨道设计参数初值提供正确参考。最后以伪倾角为窗口特性分析参数,发现了近月点窗口、近地点出发位置的变化规律。仿真结果表明,本文提出的伪经度搜索方法能够快速求解着陆器地月转移轨道,同时揭示了环月到达轨道(LLO)与近地出发轨道(LEO)之间的内在联系,研究结论可为未来载人登月工程提供借鉴。  相似文献   

13.
针对两种典型硅橡胶基防热涂层开展高温燃气流烧蚀实验,通过对烧蚀后涂层的宏观及微观形貌分析,探讨了其防隔热机理及烧蚀模型。研究结果表明:烧蚀后两种涂层均存在液态层、陶瓷层、热解层以及原始层;烧蚀过程中甲基苯基硅橡胶涂层主要发生主链“回咬”成环反应,导致树脂基体交联密度降低,力学性能下降,涂层外表面发生开裂,甲基乙烯基硅橡胶涂层则主要发生侧基交联反应,使树脂基体交联密度上升,促进涂层发生陶瓷化转变;热辐射、热容吸热、热解反应吸热以及热阻塞效应为四种主要的热耗散机制,质量损失产生的原因主要包括反应气体释放以及气动剪切力导致的机械剥蚀。  相似文献   

14.
In Japan, there are several government ministries and agencies with important roles in the development and use of space. In 2012, Japan restructured its administrative organs related to the development and use of space through legal amendments to the original acts that established these organs. Although this was an important administrative reform that took four years of planning and discussion to accomplish, this restructuring has not been communicated well outside of Japan. This study provides the first comprehensive overview of the recent legal changes in Japanese space policy. In contrast to some reports, the Ministry of Education, Culture, Sports, Science and Technology (MEXT) still has primary responsibility for the finances and personnel of the Japan Aerospace Exploration Agency (JAXA). This continues to be true even after the Cabinet Office begins its new role as the focal point for formulating Japanese space policy. It remains to be seen how the policy direction of the Cabinet Office will interact with the operational, financial, and personnel responsibilities of MEXT. I argue that knowledge of the roles of MEXT and the Cabinet Office in space policy, and the tension between the two organizations, is key to understanding Japan's future space policy decision-making process. By tracing the history of Japanese space policy since 2001, I also suggest that if bureaucrats had thought more deeply before making major reforms to space policy and its administration, there would have been less confusion over the development of national space policy this past decade. This paper concludes by identifying some key elements to monitor in the coming years of Japan's space policy.  相似文献   

15.
Richard Ohlemacher   《Space Policy》2003,19(4):277-281
The world's first political summit on Earth observation was attended by senior policy makers and expert organizations from a range of scientific disciplines. Its aim was to improve global cooperation in Earth observation and increase its use as a decision-making tool for sustainable development and resource conservation. This article presents a brief survey of the progress made in Earth observation since its birth, along with the specific events driving the convening of the summit. The summit produced a declaration outlining four key areas requiring support, and an ad hoc group was established to produce a 10-year plan and drive implementation of policy.  相似文献   

16.
As economic pressure and competition for budget among federal agencies has increased, there has been an increasing need for more granular data and robust management information systems. This is especially true for the execution of major civilian space programs. This need has resulted in new program management requirements being implemented in an attempt to limit cost and schedule growth. In particular, NASA Procedural Requirements (NPR) 7120.5D requires the implementation of an Earned Value Management System (EVMS) compliant with the requirements of American National Standards Institute (ANSI)/Electronic Industries Alliance Standard 748-B. The Radiation Belt Storm Probes (RBSP) program management team at The Johns Hopkins University Applied Physics Laboratory (JHU/APL) made a decision to implement an EVMS on RBSP during Phase B—a year earlier than specified in the contractual Phase C reporting requirement as defined in the NPR. This decision was made so that the project would have the benefit of 12 months of training and hands-on implementation during Phase B. Although there were a number of technical and process hurdles encountered during Phase B and into Phase C, the system was working well when the Integrated Baseline Review (IBR) was held in August 2009. The IBR was a success because it met the review requirements. It was also clear to all IBR participants that the EVMS was providing value to the project management team. Although the IBR pointed out some areas of concern regarding process and ANSI compliance, the system had markedly improved the project's ability to monitor cost and schedule. This, in turn, allowed the project team to foresee problems in advance, formulate corrective actions, and implement course corrections without causing significant adverse impact to the project. Opponents of EVMS systems often communicate the unfavorable opinion that EVMS systems create unnecessary cost and administration. Although it is undeniable that EVMS implementation does not occur without cost, the cost is minimal in comparison to the benefits of successful implementation. This paper will focus on the implementation of EVMS on the RBSP project, explain EV processes and the implementation's cost, and analyze the benefits of EVMS to provide insight into cost/benefit considerations for other projects considering EVMS implementation. This paper will do this by focusing on the following points: (1) RBSP is the first full-up implementation of earned value management (EVM) at JHU/APL; (2) RBSP EVM started in Phase B; (3) RBSP EVM implementation has been working well in Phase C/D; (4) RBSP EVM implementation has been recognized by Goddard Space Flight Center and NASA Headquarters as successful; and (5) an assessment of the benefits of EVMS to the project management team and sponsor shows that the system's benefits outweigh the cost of implementation.  相似文献   

17.
China's space policy and its purpose have become an increasingly contentious subject. This paper critically examines the claims, made by Ashley Tellis, among others, that China has a space strategy decided and coordinated by the Chinese military and dedicated to defeating superior US power locally in an asymmetrical war, and that it is this military space strategy that drives China's single-minded pursuit of space science and technology and the development of China's space programme. To do so, the paper conducts two investigations: into the declining role of the Chinese military in China's foreign and security policy making and its limited influence in formulating China's grand strategy; and the other into the contingent history of China's two space programs, Shenzhou and Chang'e, which have largely been driven by civilian scientist communities, rather than the military. In so doing, I argue that the claims of China's ‘military space strategy’ are over-imaginative and serve a particular political purpose. The social imaginary of a threatening China produced by the US strategic gaze at China in space, I further argue, has dangerous policy implications.  相似文献   

18.
In 1996, the National Research Council's Committee on Risk Characterization argued convincingly for the implementation of more participatory approaches to improve policy making by incorporating a wide range of stakeholder values and concerns in policy decisions. Guidance about how to best carry out such an approach in an agency like NASA is less clear. To address this gap, this paper discusses how the use of a structured approach to involve expert and non-expert stakeholders in policy making can improve the quality of stakeholder involvement and resulting decisions for space policy making at NASA. Supporting this discussion are results from two recent experiments. One compared the quality and type of participants’ input in a conventional stakeholder workshop with that of a more structured participatory process. The results from this experiment showed that a structured decision approach leads to more thoughtful and better-informed decisions. A second experiment showed that structured, participatory decision processes can help to legitimize space policy decisions after they have been implemented, leading to future benefits for the space agency.  相似文献   

19.
夏时宇  徐波 《宇航学报》2019,40(3):258-265
为更准确地描述大气飞行过程,提出一种三段式大气飞行模型,将大气飞行段分为下降段、平飞段和上升段,使用大气飞行角和航迹角描述飞行过程,并建立了相应的计算模型。对“地球-火星-地球”、“地球-火星-金星-地球”和“地球-金星-火星-地球”自由返回轨道序列的优化结果表明,三段式模型可以准确描述气动引力辅助过程,同时气动引力辅助技术可以有效提升自由返回轨道性能,如减少转移时间,降低燃料消耗等。  相似文献   

20.
《Space Policy》2014,30(4):226-230
We are witnessing a fundamental change in the perception of space-related issues. Once a symbol of technological competition between opposing political systems, space activities have become a part of everyday life and an indispensable means for states to achieve economic, scientific, political and social goals. This Report addresses the space activities of Turkey, a latecomer to space challenge but a country rapidly progressing in this field. In this context, major space-related policies and projects are first discussed. The current status of the Turkish space industry is then defined through SWOT analysis (strengths, weaknesses, opportunities, threats). The analysis is informed by a May 2012 workshop was held in Turkey at the Defense Sciences Institute, which brought together a range of interested actors to discuss Turkey's space policy. The workshop was followed up six months later with a survey of a larger group of participants. This Report lays out the findings of these two events, articulating the strengths and weaknesses for Turkey's space aspirations, and also a proposal for the country's future space ambitions. Strategies and policies that will be supportive in achieving the proposed space vision are also introduced.  相似文献   

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