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1.
自由滚转尾翼试飞器滚转特性分析   总被引:1,自引:0,他引:1  
自由滚转尾翼是解决鸭式布局导弹的鸭式舵难以差动兼作副翼进行滚动控制的一种技术途径.为验证某鸭式布局试飞器采用自由滚转尾翼方案的可行性,进行了试飞器的固定尾翼和自由滚转尾翼两种模型的风洞试验.试验结果表明,固定尾翼试飞器,当鸭舵作副翼偏转进行滚控时,在尾翼上会产生很大的诱导滚动力矩,抵消鸭舵的控制力矩,致使鸭舵不能进行滚转控制;滚转尾翼可有效减小诱导滚动力矩,实现通过鸭舵进行全弹滚转控制的目的.  相似文献   

2.
In the first Spacelab Mission which will take place in Sept. Oct. 1983 a Metric Camera will be flown as part of the Earth observation payload. The camera will be a modified high quality Aerial Survey Camera.The hardware development is finished and the instrument is already integrated into Spacelab.The application of Metric Cameras in Space, an area which is neglected up to now, can effectively contribute to an improved cartographic coverage of the Earth. The Metric Camera Experiment is a first step to fill this gap which can be realized by utilizing the extended capacities of the Space Transportation System.The paper outlines the scientific objectives of the experiment, describes in detail the camera system and deals with the operation and control philosophy during the mission.  相似文献   

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石玉红  肖耘  徐卫秀 《宇航学报》2004,25(5):484-487
最大速度头试验是指模拟运载火箭在最大速度头状态(Qmax)出现故障时,考核逃逸飞行器的工作情况。通过试验获得逃逸飞行器环境及性能参数;考核其结构强度;考核栅格翼释放机构的功能。试验涉及逃逸飞行器结构、遥测系统、外测系统、火箭车动力系统、火工品控制系统等,属于大型综合性试验,难度大,风险高。本文简述了CZ-2F逃逸飞行器的功能,介绍了最大速度头地面模拟飞行试验目的、方案设计及结果分析,得出了相应的结论。  相似文献   

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浅析飞行危险天气影响航路飞行区域的划设方法   总被引:1,自引:0,他引:1  
引言 飞行危险天气是影响航空安全,导致航班延误的首要原因。随着全球航空运输业务量的不断增加,研究在危险天气影响下如何安全、高效地飞行已迫在眉睫。飞行危险天气主要包括:雷暴、低空风切变、飞机颠簸、飞机积冰、大风和视程障碍,其中涉及航路飞行的危险天气主要为雷暴,及伴随其产生的其他天气现象。雷暴是由对流旺盛的积雨云引起的伴有闪电雷鸣的局地风暴,它是积雨云强烈发展的标志。  相似文献   

7.
Richard Rovetto has done a good job of assembling various arguments that are commonly advanced for a program of manned space flight. I will take them up one by one, and explain why I find them all unconvincing.  相似文献   

8.
Estimates of the cost of human space flight continue to generate controversy in the effort to set US space policy. Estimates vary widely, depending upon the position of the observer. This article identifies the real cost of major space flight programs and traces the heterofore unsuccessful efforts to cut the expense of space operations.  相似文献   

9.
Cell-to-cell interactions play an important role in all physiological processes and are mediated by humoral and mechanical factors. Mechanosensitive cells (e.g., osteocytes, chondrocytes, and fibroblasts) can be studied ex vivo to understand the effects of an altered gravity environment. In particular, cultured endothelial cells (EC) are very sensitive to a broad spectrum of mechanical and biochemical stimuli. Earlier, we demonstrated that clinorotation leads to cytoskeletal remodeling in cultured ECs. Long-term gravity vector changes also modulate the expression of surface adhesion molecules (ICAM-1, E-selectin, VCAM-1) on cultured ECs. To study the interactions of geterological cells, we cocultured endothelial monolayers and human lymphocytes, immune cells and myeloleucemic (K-560) cells. It was found that, although clinorotation did not alter the basal adhesion level of non-activated immune cells on endothelial monolayers, the adhesion of PMA-activated lymphocytes was increased. During flight experiments onboard the Russian segment of the International Space Station, we measured the cytotoxic activity of natural killer (NK) cells incubated with labeled target cells. It was found that immune cells in microgravity retained their ability to contact, recognize, and destroy oncogenic cells in vitro. Together, our data concerning the effects of simulated and real microgravity suggest that, despite changes in the cytoskeleton, cell motility, and expression of adhesion molecules, cell-cell interactions are not compromised, thus preserving the critical physiological functions of immune and endothelial cells.  相似文献   

10.
Changes in body fluids, electrolytes, and muscle mass are manifestations of adaptation to space flight and readaptation to the 1-g environment. The purposes of this paper are to review the current knowledge of biomedical responses to short- and long-duration space missions and to assess the efficacy of countermeasures to 1-g conditioning. Exercise protocols, fluid hydration, dietary and potential pharmacologic measures are evaluated, and directions for future research activities are recommended.  相似文献   

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One year after the achievemant of the 2 weeks ANTARES french-russian mission in the MIR station in July 1992, a 22 days ALTAÏR mission with a french cosmonaut has been performed in July 1993, making use of the scientific payload remaining on board. Taking benefit of the analysis of the previous mission, the experimental protocols were adapted to refine scientific objectives and gave to the scientists the opportunity to enhance quantitatively and qualitatively their results. The french biomedical program, conducted in close scientific cooperation with IMBP and associated laboratories, was composed of 8 experiments out of which 2 were new with regards to the ANTARES program. In the field of cardio-vascular physiology and fluid regulation, the experiments: ORTHOSTATISME, DIURESE have been renewed and complemented by the TISSU experiment (proposed by a german scientist) and a real-time tele-assistance program using US echography technic and ground support from the french CADMOS support control center located in Toulouse. With respect to neurosciences objectives, to the experiments VIMINAL (cognitive processes) and ILLUSIONS (study of proprioceptives cues), was added the SYNERGIES experiment to analyse the postural adjustements during movement. The IMMUNOLOGIE experiment carried on and the radiobiological experiment BIODOSE ended.

Adding the results of the 2 missions ANTARES and ALTAÏR, and the data obtained in between onboard with russian cosmonauts, the scientists have received a wealth of physiological data and gained reproducibility and confidence in their results.  相似文献   


13.
A nanosatellite to investigate the brightness oscillations of massive luminous stars by differential photometry is currently developed by a Canadian/Austrian team within the BRITE (Bright Target Explorer) project. The first Austrian satellite funded by the Austrian Space Program, called TUGSAT-1/BRITE-Austria, builds on the space heritage of the most successful Canadian CanX-2 and MOST missions. The satellite makes use of recent advances in miniaturized attitude determination and control systems. Precision three-axis stabilization by small reaction wheels and a star tracker provides the necessary accuracy for the photometer telescope to the arcminute level. This will provide to the astronomers photometric data of the most massive stars with unprecedented precision; data which cannot be obtained from the ground due to limitations imposed by the terrestrial atmosphere.The paper describes the spacecraft characteristics and the ground infrastructure being established in support of the BRITE mission which will consist of a constellation of up to four nearly identical satellites allowing to carry out long-term observation of stars (magnitude +3.5) not only with respect to brightness variations, but also in different spectrum ranges.  相似文献   

14.
Blood pressure at 30-sec intervals, heart rate, and percentage increase in leg volume continuously were recorded during a 25-min protocol in the M092 Inflight Lower Body Negative Pressure (LBNP) experiment carried out in the first manned Skylab mission. These data were collected during six tests on each crewman over a 5-month preflight period. The protocol consisted of a 5-min resting control period, 1 min at -8, 1 min at -16, 3 min at -30, 5 min at -40, and 5 min at -50 mm Hg LBNP. A 5-min recovery period followed. Inflight tests were performed at approximately 3-day intervals through the 28-day mission. Individual variations in cardiovascular responses to LBNP during the preflight period continued to be demonstrated in the inflight tests. Measurements of the calf indicated that a large volume of fluid was shifted out of the legs early in the flight and that a slower decrease in leg volume, presumably due to loss of muscle tissue, continued throughout the flight. Resting heart rates tended to be low early in the flight and to increase slightly as the flight progressed. Resting blood pressure varied but usually was characterized by slightly elevated systolic blood pressure, lower diastolic pressure, and higher pulse pressures than during preflight examinations. During LBNP inflight a much greater increase in leg volume occurred than in preflight tests. Large increases occurred even at the smallest levels of negative pressure, suggesting that the veins of the legs were relatively empty at the beginning of the LBNP. The greater volume of blood pooled in the legs was associated with greater increases of heart rate and diastolic pressure and larger falls of systolic and pulse pressure than seen in preflight tests. The LBNP protocol represented a greater stress inflight, and on three occasions it was necessary to stop the test early because of impending syncopal reactions. LBNP responses inflight appeared to predict the degree of postflight orthostatic intolerance. Postflight responses to LBNP during the first 48 hours were characterized by marked elevations of heart rate and instability of blood pressure. In addition, systolic and diastolic pressures were typically elevated considerably both at rest and also during stress. The time required for cardiovascular responses to return to preflight levels was much slower than in the case of Apollo crewmen.  相似文献   

15.
The tether assisted re-entry of small payloads is a highly interesting tool for space transportation especially for the return of small payloads from Space Station ISSA. The small tether mission Rapunzel was initiated in 1991 by the Institute of Astronautics, TU München and the Kayser-Threde Company, to design a low cost and feasible tether experiment for the verification of the tether assisted re-entry. Together with the Samara State Aerospace University, Russia, a mission concept on a Russian Resurs or Photon capsule was developed. Based on this mission a deployer has been designed, mainly based on technology of the textile industry, which insures high reliability at low cost. Recently a similar configuration is being discussed for the ESA-TSE mission.The main work during the recent time was the development and test of the breadboard model of the deployer system. After successfully completing initial ground tests with the deployer, further tests during the ESA Parabolic Flight campaign in November 1995 were conducted. After a short introduction of the overall mission scenario, the planned configuration in orbit, this paper will present the results of the microgravity test campaign onboard the KC-135 aircraft and compare them with the ground test. The deployer showed a good performance during all tests, including ejection of the end-mass, deployment, and braking. Problems that occurred during the tests will be discussed, and solutions for the detected flaws and the results of the redesign now in progress will be presented. These verifications have shown the feasibility of the concept and will lay the base for the planned development of the flight model of the deployer.  相似文献   

16.
McPhee JC  White RJ 《Acta Astronautica》2003,53(4-10):239-248
The hazards of long-duration space flight are real and unacceptable. In order for humans to participate effectively in long-duration orbital missions or continue the exploration of space, we must first secure the health of the astronaut and the success of such missions by assessing in detail the biomedical risks of space flight and developing countermeasures to these hazards. Acquiring the understanding necessary for building a sound foundation for countermeasure development requires an integrated approach to research in physiology and medicine and a level of cooperative action uncommon in the biomedical sciences. The research program of the National Space Biomedical Research Institute (NSBRI) was designed to accomplish just such an integrated research goal, ameliorating or eliminating the biomedical risks of long-duration space flight and enabling safe and productive exploration of space. The fruits of these labors are not limited to the space program. We can also use the gained understanding of the effects and mechanisms of the physiological changes engendered in space and the applied preventive and rehabilitative methods developed to combat these changes to the benefit of those on Earth who are facing similar physiological and psychological difficulties. This paper will discuss the innovative approach the NSBRI has taken to integrated research management and will present some of the successes of this approach.  相似文献   

17.
The EU 7th Framework Project FAST20XX [1] aimed to enlarge the foundations of suborbital high-speed transportation in a wide variety of fields. One of the key issues of this project was to outline a desirable regulatory framework that would best serve the interests of all European stakeholders in this new activity.  相似文献   

18.
公务飞行市场是中国民航业中一个新兴的细分市场,该细分市场目前正方兴未艾,虽然现在刚刚起步,但随着中国经济的不断发展其发展潜力不可小觑。可以预测,民航未来发展最快的就将是公务飞行市场。  相似文献   

19.
对设计变量的偏差量进行建模,拟合偏差量服从的概率密度函数,是分析评价飞行器性能和概率设计的重要基础.针对常用分布拟合能力有限,以及混合Gamma分布无法在整个数轴上对试验数据进行拟合的问题,在论证混合Gauss分布拟合任意概率密度函数合理性的基础上,提出了利用混合Gauss分布对试验数据进行拟合,并运用期望极大化算法(...  相似文献   

20.
为提升掠飞攻顶弹箭较高转速下的飞行稳定性,运用数值计算方法研究了弹体-扭曲尾翼组合体在飞行过程中的马格努斯效应气动机理,并应用标准尾翼弹(BFM)模型的实验数据对数值方法进行了验证。分别研究了带有平板尾翼和扭曲尾翼弹体模型的马格努斯力和力矩随攻角的变化规律,并针对弹体弹翼组合体产生马格努斯效应的机理深入分析。结果表明,扭曲尾翼可有效改善翼面的压力分布,并降低弹体对翼面马格努斯效应的干扰,在大攻角时其表现更胜一筹;弹体所受马格努斯力较大,主要集中在受到涡对称畸变的尾锥部;尾翼主要由于弹体干扰以及几何外形的影响马格努斯力集中在尾部,两者产生的马格努斯力矩数值相差不大,但方向相反。  相似文献   

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