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The Space Flyer Unit (SFU) system and mission chronology are briefly introduced. Lessons learned from the SFU mission are categorized as programmatic and engineering lessons. In the programmatic category are dealt with both international and domestic collaborations. As for the engineering lessons safety design, orbital operation, in-flight anomaly, and post flight analyses are the major topics reviewed. 相似文献
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In this paper, we explore the lessons learned from the work of the York University Rover Team (YURT), which designed, built, and operated two prototype rovers for the University Rover Challenge (URC) in 2008 and 2009, placing third in the first year, and winning first place in the second year. We outline the competition, the team, and briefly describe the York University space engineering program. Both of the rovers are described with evaluations of each major component and the resulting design changes. A general trend toward design modularity, purpose-driven customizations, and better critical thinking in the design process is evident as the team gains experience. Also, the value of this project as an educational medium is evaluated with respect to traditional classroom learning. Participating students from a wide range of disciplines gained real-world experience in both “hard” engineering skills such as mechanical and electronic design, fabrication, and testing, and “soft” skills such as project management, system-level thinking, creative problem solving, and interpersonal skills. Lessons learned from this include the necessity of good financial management, the importance of marketing and outreach, the use of short and simple development steps, and the need for comprehensive contingency planning. We conclude that the URC provided an inter-disciplinary, cooperative educational environment, and that student engineering projects such as this can provide “soft” skills through experiential education that are normally difficult to teach in the classroom. 相似文献
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In isolated and confined environments, two important leadership roles have been identified: the task/instrumental role (which focuses on work goals and operational needs), and the supportive/expressive role (which focuses on morale goals and emotional needs). On the International Space Station, the mission commander should be familiar with both of these aspects of leadership. In previous research involving a 135-day Mir space station simulation in Moscow and a series of on-orbit Mir space station missions during the Shuttle/Mir program, both these leadership roles were studied. In new analyses of the Shuttle/Mir data, we found that for crewmembers, the supportive role of the commander (but not the task role) related positively with crew cohesion. For mission control personnel on the ground, both the task and supportive roles of their leader were related positively to mission control cohesion. The implications of these findings are discussed in terms of leadership on board the International Space Station. 相似文献
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为构建具有密度误差原理级修正的热层大气模型动态修正软件系统,首先,根据温度垂直剖面计算方法,对拐点和外逸层2个边界温度计算函数按经纬度球谐系数展开,研究基于模型和实测密度估计修正系数的方法;从数值计算方面,将条件方程泰勒展开线性化迭代求解得到修正系数。然后,融合修正理论和数值方法,构建热层大气密度动态修正模型系统。之后,针对磁暴、磁静事件分类评估系统性能,结果显示修正后模型的预报准确性较MSIS00模型显著提升——预报相对误差磁暴期平均下降33.8个百分点,磁静期平均下降9.1个百分点。最后,分析边界温度修正量的序列,得到其主要变化规律。期望通过热层大气模型动态修正系统的研究与实践,为热层大气密度的高精度预测需求提供解决方案。 相似文献
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性能精度是液体火箭发动机的一项重要指标,对于上面级发动机性能精度尤其重要.以某型泵压式上面级发动机为研究对象,利用影响分析树的方法识别了发动机生产、测试、性能调整过程中影响性能精度的干扰因素;针对所识别的干扰因素,通过仿真计算,得到了其偏差对发动机推力和混合比的影响.根据统计学原理,推导得到多项干扰因素影响概率的计算模型,并利用小子样样本对计算模型和程序的正确性进行了验证.利用该概率计算模型,根据置信水平要求,确定了多项干扰因素对发动机性能的极限偏差影响.根据发动机性能精度要求,分解得到了单个干扰因素的控制目标. 相似文献
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Countries on every continent are making new or renewed commitments to domestic satellite programs. These programs have the potential to address national needs by enhancing access to information, improving infrastructure and providing inspiration to the public. How do countries without local expertise in space technology begin a new satellite program? What is the role of international collaboration in supporting the efforts of a new space fairing country? This paper explores such questions by highlighting outputs from intensive field work in Africa and Asia. Specifically, the study explores case studies of early space activity in these countries to search for lessons about the management of a young space program. The observations from field work are compared to ideas from scholarly literature on technological learning. The findings are organized using principles from systems architecture. The paper presents a model that captures many of the influences and strategic decision areas for a collaborative satellite development project. The paper also highlights the growth of capability among African countries in the area of satellite technology. 相似文献
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为研究导弹发射过程中发动机喷出的高温高速粒子对发射装置壁面的冲刷和侵蚀作用,利用MSDM(微尺度动力学模型)方法,建立了粒子对固壁材料的冲刷侵蚀模型,对粒子入射速度、入射角度、粒子尺寸及固壁材料特性等影响侵蚀效应的因素进行了研究,获得了粒子入射条件、固壁材料特性与侵蚀效应的相互关系.用MSDM方法将粒子和固壁离散为具有一定连接关系的微团质点,并利用材料属性和牛顿运动关系确定了微团间的相互作用和运动过程.研究表明,该方法在分析粒子-材料侵蚀方面具有一定效果. 相似文献
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We consider possible stages of constructing complex models of the circumterrestrial plasma including both neutral and charged
components in their interaction. At the initial stage it is suggested to use as a basis the empirical models of the upper
atmosphere and ionosphere. These models have concentrated fundamental data about the near-Earth space (NES) accumulated for
several decades of space exploration. The final goal is to construct a prognostic model which would allow one to calculate
both long-periodic variations of the NES structure (they can occur over several decades of years and more) and short-period
disturbances with a characteristic time of about a day. In order to predict the results of anthropogenic effects it is proposed
to construct imitation mathematical models that should allow one to calculate NES variations which can proceed at various
model scenarios of anthropogenic actions. 相似文献
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One of the most important problems for performing a good design of the spacecraft attitude control law is connected to its robustness when some uncertainty parameters are present on the inertial and/or on the elastic characteristics of a satellite. These uncertainties are generally intrinsic on the modeling of complex structures and in the case of large flexible structures they can be also attributed to secondary effects associated to the elasticity. One of the most interesting issues in modeling large flexible space structures is associated to the evaluation of the inertia tensor which in general depends not only on the geometric ‘fixed’ characteristic of the satellite but also on its elastic displacements which of course in turn modify the ‘shape’ of the satellite. Usually these terms can be considered of a second order of magnitude if compared with the ones associated to the rigid part of a structure. However the increasing demand on the dimension of satellites due to the presence for instance of very large solar arrays (necessary to generate power) and/or large antennas has the necessity to investigate their effects on their global dynamic behavior in more details as a consequence. In the present paper a methodology based on classical Lagrangian approach coupled with a standard Finite Element tool has been used to derive the full dynamic equations of an orbiting flexible satellite under the actions of gravity, gravity gradient forces and attitude control. A particular attention has been paid to the study of the effects of flexibility on the inertial terms of the spacecraft which, as well known, influence its attitude dynamic behavior. Furthermore the effects of the attitude control authority and its robustness to the uncertainties on inertial and elastic parameters has been investigated and discussed. 相似文献
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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
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This article aims to illustrate how the predominant role of the US military space capabilities within NATO adversely affects the European space industry's competitiveness and performance, as compared with the USA space industry. Thus, first the intra-NATO specialization is illustrated, followed by an analysis of the economics of the space industry. The connection is made through an economics model whose results verify the hypothesis, and predicts that the recent commitment by the WEU to military space can improve the position of the European space industry, especially if followed by close cooperation between the WEU and ESA. 相似文献