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81.
This paper briefly introduces the history of China's Manned Space Flight Program and concludes the experiments done since 2008, namely, a small satellite and a material science experiment. An outlook of future Chinese Space Station is also described at the end.   相似文献   
82.
为了完成航天员的出舱活动任务,必须建设可以验证航天员出舱活动适应性的地面试验设备。文章描述了航天员出舱活动地面试验设备的系统构成、性能指标以及实现方法,给出了航天员出舱活动试验过程的实际过程曲线。试验结果表明:该地面试验设备可以满足航天员出舱活动试验任务的要求,拓宽了空间环境地面试验的领域范围,提升了空间环境地面模拟的能力,并为后续有人参与的空间环境地面试验提供了能力保证。  相似文献   
83.
General relativity (GR) can be probed by several tests in the weak gravitational field limit. On the contrary, very poor information exists about GR tests in strong gravitational fields. Here, we focus on the interaction of light rays with the strong gravitational field of a massive black hole and show that relativistic images may form. Hence, we calculate the shapes of shadows (mirages) forming just near BH horizons and discuss the possibility to estimate the black hole parameters (mass, spin and charge) by future astrometric missions. In 2007, the Radioastron space telescope will be launched and it will allow to evaluate those parameters for the black hole hosted at the center of our Galaxy.  相似文献   
84.
Design reliability and robustness are getting increasingly important for the general design of aerospace systems with many inherently uncertain design parameters. This paper presents a hybrid uncertainty-based design optimization (UDO) method developed from probability theory and interval theory. Most of the uncertain design parameters which have sufficient information or experimental data are classified as random variables using probability theory, while the others are defined as interval variables with interval theory. Then a hybrid uncertainty analysis method based on Monte Carlo simulation and Taylor series interval analysis is developed to obtain the uncer-tainty propagation from the design parameters to system responses. Three design optimization strategies, including deterministic design optimization (DDO), probabilistic UDO and hybrid UDO, are applied to the conceptual design of a hybrid rocket motor (HRM) used as the ascent propulsion system in Apollo lunar module. By comparison, the hybrid UDO is a feasible method and can be effectively applied to the general design of aerospace systems.  相似文献   
85.
Active shielding for long duration interplanetary manned missions   总被引:1,自引:0,他引:1  
For long duration interplanetary manned missions the protection of astronauts from cosmic radiation is an unavoidable problem that has been considered by many space agencies. In Europe, during 2002–2004, the European Space Agency supported two research programs on this thematic: one was the constitution of a dedicated study group (on the thematic ‘Shielding from cosmic radiation for interplanetary missions: active and passive methods’) in the framework of the ‘life and physical sciences’ report, and the other an industrial study concerning the ‘radiation exposure and mission strategies for interplanetary manned missions to Moon and Mars’. Both programs concluded that, outside the protection of the magnetosphere and in the presence of the most intense and energetic solar events, the protection cannot rely solely on the mechanical structures of the spacecraft, but a temporary shelter must be provided. Because of the limited mass budget, the shelter should be based on the use of superconducting magnetic systems. For long duration missions the astronauts must be protected from the much more energetic galactic cosmic rays during the whole mission period. This requires the protection of a large habitat where they could live and work, and not the temporary protection of a small volume shelter. With passive absorbers unable to play any significant role, the use of active shielding is mandatory. The possibilities offered by superconducting magnets are discussed, and recommendations are made about the needed R&D. The technical developments that have occurred in the meanwhile and the evolving panorama of possible near future interplanetary missions, require revising the pioneering studies of the last decades and the adoption of a strategy that considers long lasting human permanence in ‘deep’ space, moreover not only for a relatively small number of dedicated astronauts but also for citizens conducting there ‘normal’ activities.  相似文献   
86.
Jupiter’s icy moon Europa is one of most promising places in our Solar System where possible extraterrestrial life forms could exist either in the past or even presently. The Europa Lander mission, an exciting part of the international Europa Jupiter System Mission (EJSM/Laplace), considers in situ planetary exploration of the moon. The distance of Europa from the Earth and the Sun asks for autonomous analytical tools that maximize the scientific return at minimal resources, demanding new experimental concepts. We propose a novel instrument, based on the atomic spectroscopy of laser generated plasmas for the elemental analysis of Europa’s surface materials as far as it is in reach of the lander for example by a robotic arm or a mole, or just onboard the lander. The technique of laser-induced plasma spectrometry provides quantitative elemental analysis of all major and many trace elements. It is a fast technique, i.e. an analysis can be performed in a few seconds, which can be applied to many different types of material such as ice, dust or rocks and it does not require any sample preparation. The sensitivity is in the range of tens of ppm and high lateral resolution, down to 50 μm, is feasible. In addition, it provides the potential of depth profiling, up to 2 mm in rock material and up to a few cm in more transparent icy matrices. Key components of the instrument are presently developed in Germany for planetary in situ missions. This development program is accompanied by an in-depth methodical investigation of this technique under planetary environmental conditions.  相似文献   
87.
载人运输飞船流体回路试验研究   总被引:2,自引:0,他引:2  
详细介绍了载人运输飞船热控船流体回路主要技术方案,包括系统组成与流程设计、工作模式设计、主要技术状态等,并列出了流体回路全部试验工况及相关试验结果,试验结果表明流体回路具有良好的温度调控能力和适应能力。重点对流体回路辐射器、冷凝干燥器、冷板、换热器等设备换热能力及低温情况下工质体积补偿、低压情况下工质溶气释出导致泵压头波动等问题进行了分析。最后根据分析和试验结果对系统提出了优化改进建议。  相似文献   
88.
轨迹/飞行器总体参数的一体化优化方法研究   总被引:4,自引:0,他引:4  
王志刚  严辉 《飞行力学》1997,15(2):19-26
基于飞行力学、最优控制理论、最优化方法,采用两种轨迹/飞行器总体参数的一体化优化方法--静态+动态一体化优化方法和参数最优化方法,研究载人飞船再入的轨迹/总体参数的优化,并比较了两种一体化优化方法的不同特点。通过数字计算,得到飞船的最优滚转程序、升阻比,再入角和再人终端时间。结果分析表明,两种一体化优化方法有得到较高精度。  相似文献   
89.
遗传算法在载人飞船返回轨道一体化设计中的应用   总被引:1,自引:0,他引:1  
吴美平  胡小平 《宇航学报》2001,22(3):99-104
载人飞船返回再入轨道设计的主要任务是确定出标准返回轨道和再入制导规律。遗传算法具有全局寻优的特点,适合于工程设计的要求。文章探讨采用遗传算法实现飞船返回轨道的一体化设计,并给出飞船返回轨道设计步骤。  相似文献   
90.
载人飞船的一种混合再入制导方法   总被引:2,自引:2,他引:2  
提出了载人飞船的一种混合再入制导方法,即在制动段结束后的过渡段,利用落点预报及其制导规律在轨生成一条基准再入弹道,在再入段利用基准弹道制导规律实现再入升力控制的一种方法。该方法融合了落点预报制导方法和基准弹道制导方法的长处。相对基准弹道制导方法,该方法可对付较大的初始误差,达到较高的精度;相对落点预报制导方法,在再入段减少了计算量。数学仿真结果验证本方法是有效的。  相似文献   
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