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1.
Chilin  Yu. N.  Evdokimov  R. A. 《Cosmic Research》2001,39(5):504-516
The conceptual and methodological principles, as well as some results of the comprehensive substantiation of a technical approach at early stages of design of power-propellant systems (PPS), are presented. By the PPS of a spacecraft is meant a set of devices for production, transformation, and distribution of energy onboard orbital vehicles. The element-stream matrix is suggested to be used as a rational form of representing the PPS structure.  相似文献   

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3.
航天器装配定位机构是重要的技术改造项目之一,用于舱段精密对接与分解,其通过与空间定位系统、自动起吊装置的配合,实现舱段对接与分解过程的量化识别与自动控制。该机构主要设计有质心捕获、自动调平和旋转等功能,为舱段对接与分解提供基础支撑平台、航天器空间姿态调整和相关数据支持。文章阐述了航天器装配定位机构原理,并对其主要功能的实现方法进行了设计。  相似文献   

4.
航天器密封舱流动和传热的数值研究   总被引:5,自引:1,他引:5  
钟奇  刘强 《宇航学报》2002,23(5):44-48
在有强迫流动的航天器密封舱内,与固壁存在热交换的三维气体流动使得舱内传热相当复杂。本文用数值分析模拟航天器在轨状态下的流动和传热。结果表明,辐射和流动在密封舱热分析中都不可忽略。对多种风速的计算结果表明,平均对流换热系数与风扇布局基本无关而仅与平均风速有关,最后由计算结果得出了平均对流换热系数和平均风速的经验关系式。  相似文献   

5.
The results of numerical solution of the problem of a rendezvous in the central Newtonian gravitational field of a controlled spacecraft with an uncontrollable spacecraft moving along an elliptic Keplerian orbit are presented. Two variants of the equations of motion for the spacecraft center of mass are used, written in rotating coordinate systems and using quaternion variables to describe the orientations of these coordinate systems. The problem of a rendezvous of two spacecraft is formulated [1, 2] as a problem of optimal control by the motion of the center of mass of a controlled spacecraft with a movable right end of the trajectory, and it is solved on the basis of Pontryagin's maximum principle. The paper is a continuation of papers [1, 2], where the problem of a rendezvous of two spacecraft has been considered theoretically using the two above variants of the equations of motion for the center of mass of the controlled spacecraft.  相似文献   

6.
研究欠驱动刚性航天器受到正弦干扰力矩作用时的旋转轴指向稳定控制问题。采用欧拉-泊松形式描述航天器的运动方程,然后分别针对轴对称情况和非轴对称情况设计控制律,并结合Lyapunov直接法和LaSalle不变性定理证明控制律的全局渐近稳定性。理论分析和仿真结果都表明新的控制律能够实现旋转轴指向全局渐近稳定。  相似文献   

7.
The hazards of microbial contamination in life support systems onboard spacecraft during long duration missions are presented. Tables present information about microbial characteristics of moisture-containing substrates and wastes submitted to and passing the regeneration system; the content of microflora on different types of polymers typically used in regenerative systems; and medical risks associated with microflora isolated from space object construction materials in spacecraft. Priorities for decontamination are total decontamination, localization of decontaminating equipment before and after regeneration, and physical methods of decontamination.  相似文献   

8.
The problem of maintenance of the equipotentiality of spacecraft surfaces is considered. The method under examination is the use of the conductive thermal-vacuum multilayer blanket (CMLB), whose outer surface represents a fabric woven of threads of glass fiber type with interwoven metal threads. The process of spacecraft potential formation and methods of the potential calculation are described, and the results of such a calculation for the illuminated and shadowed parts of spacecraft surfaces in some characteristic near-Earth plasma environments are presented. The CMLB model is described, and the potential distribution near the CMLB surface is calculated. The conclusion was drawn that the conductive thermal-vacuum multilayer blanket used in some cases on Russian spacecraft does not ensure the equipotentiality of spacecraft surfaces, and in the case of using CMLB, the differential spacecraft charging in outer regions of the Earth's magnetosphere may reach a dangerous level for onboard electronic systems. In spite of the fact that CMLB guards against large-scale powerful discharges, one cannot exclude discharges completely, what may result in broadband noise enhancement and cause onboard systems failures.  相似文献   

9.
姚郁  谢瑞强 《宇航学报》2007,28(4):831-834
从航天器微小型化的角度出发,提出了仅利用两个飞轮进行航天器姿态控制的飞轮配置方案。该方案还可以对高速旋转的飞轮所储存的能量进行管理,不需要磁力矩器等额外的卸载装置,从而简化了飞轮姿态控制系统的结构。详细描述了系统的结构和工作原理,推导了航天器姿态控制系统的非线性动力学模型,分析了影响航天器姿态机动性能的主要因素,并通过仿真验证了这种配置方案的有效性。  相似文献   

10.
空间材料放气污染特性研究技术   总被引:4,自引:3,他引:1  
文章阐述了空间材料放气污染对航天器的影响,并介绍了建立的放气污染特性研究装置和E595材料筛选标准装置,它可用于多种放气污染特性的研究,文章还给出了应用实例.  相似文献   

11.
航天微系统技术综述   总被引:1,自引:0,他引:1  
航天微系统技术包括专用集成电路(ASIC)、片上系统(SoC)、单片微波集成电路(MMIC)、混合集成电路(HIC)等微电子技术和微机电系统(MEMS)。文章介绍了这几种技术的特点、发展现状,以及在航天中的应用情况和应用前景。ASIC与SoC技术可显著提高电子系统的集成度和性能,已在航天中得到广泛应用。MMIC技术可用于航天器通信载荷和平台的射频通信部件,已在欧美航天器中大量应用,目前正朝高频段发展。HIC主要包括厚膜HIC和薄膜HIC,特别适于功率器件和微波器件的集成,目前国外已有大量产品用于航天,如"国际空间站"(ISS)。MEMS技术可用于航天器导航、热控、推进、光学遥感与通信等系统,甚至可对航天器设计方法产生重要影响,但目前还处于起步阶段。在以上技术领域,我国虽已开展了一些研究,但与国外相比还存在较大差距。文章针对航天微系统技术的产业布局、发展方式等提出了建议,可为我国的发展规划和战略决策提供参考。  相似文献   

12.
The paper provides a survey of novel mission concepts for continuous, hemispheric polar observation and direct-link polar telecommunications. It is well known that these services cannot be provided by traditional platforms: geostationary satellites do not cover high-latitude regions, while low- and medium-orbit Sun-synchronous spacecraft only cover a narrow swath of the Earth at each passage. Concepts that are proposed in the literature are described, including the pole-sitter concept (in which a spacecraft is stationary above the pole), spacecraft in artificial equilibrium points in the Sun–Earth system and non-Keplerian polar Molniya orbits. Additionally, novel displaced eight-shaped orbits at Lagrangian points are presented. For many of these concepts, a continuous acceleration is required and propulsion systems include solar electric propulsion, solar sail and a hybridisation of the two. Advantages and drawbacks of each mission concept are assessed, and a comparison in terms of high-latitude coverage and distance, spacecraft mass, payload and lifetime is presented. Finally, the paper will describe a number of potential applications enabled by these concepts, focusing on polar Earth observation and telecommunications.  相似文献   

13.
为提高载人航天器电测的效率和准确性,文章引入自动判读系统。该系统判读知识表达可支持多种运算符和函数,知识覆盖面广;推理机的设计充分考虑了载人航天器测试的特点,数据判读准确性高,实时性好。系统目前已实现参数判读、指令判读、事件判读和指令监视等功能,在后续载人航天器电测中将发挥更重要的作用。  相似文献   

14.
航天器的连接与分离技术是航天运输系统中的关键技术,连接分离装置作为该技术领域的关键装置,一直是航天领域的重要研究内容。针对航天器连接与分离的要求,提出一种涡卷弹簧非火工分离螺母装置,并对装置进行结构设计。涡卷弹簧是装置的关键部分,直接影响涡卷弹簧分离螺母装置的承载和工作特性。对涡卷弹簧的张力和扭矩特性进行分析,并通过仿真分析研究涡卷弹簧分离螺母装置的工作特性。  相似文献   

15.
在轨释放、分离载荷动力学仿真研究   总被引:2,自引:1,他引:1  
某些航天器需要在飞行过程中释放、分离载荷,由此涉及的动力学问题,关系到航天器平台与载荷的控制。文章主要对此类航天器的多体动力学问题进行研究,基于机械系统动力学仿真分析(ADAMS)软件平台建立了包括航天器平台、载荷和两类分离机构等在内的仿真模型,通过对三种在轨释放、分离载荷方案的分离过程动力学仿真结果对比分析以及参数化仿真分析,为载荷释放、分离方案设计提供参考。  相似文献   

16.
Nazarenko  A.I.  Chobotov  V.A. 《Space Debris》1999,1(2):127-142
Initial orbital parameter errors are used to examine the miss distance between a spacecraft and an ensemble of tracked objects by a Monte Carlo-type analysis. The radial separation between orbits is evaluated and a keep-out zone is determined, which reduces the risk of collision to an acceptable level.An operational prediction methodology is suggested based on a catalog database, which identifies potentially hazardous approaches and computes the probability of collision for selected spacecraft. An example for the Mir Space Station is presented, which estimates the collision probability and the cross-sectional flux of cataloged objects for the time frame of interest. The results appear to be in good agreement with those of other space debris models.  相似文献   

17.
航天器充放电在轨探测试验的发展   总被引:1,自引:0,他引:1  
介绍了航天器充放电中表面充电和深层介质充电的产生原因,以及充放电试验的发展。分析了国外瞬态脉冲监测仪(TPM)、充电电气效应分析仪(CEEA)、IDM装置、PASP Plus试验、集约环境异常传感器(CEASE)、DDE试验,以厦悬浮电位探测单元(FPMU)等充放电试验的原理厦其试验结果。最后,根据国外的经验和发展趋势,对国内航天器充放电在轨测试的目的、发展步骤,以及与各种空间物理量的关系等提出了相应的建议。  相似文献   

18.
文章描述了一个用于航天器防护结构综合优化的独特方法——几何规划优化技术,以减小暴露于流星体和空间碎片超高速碰撞环境下的航天器防护结构系统的重量。空间碎片和流星体环境由广义加权目标函数的公式来定义。通过Wilkinson,Burch和Nysmith超高速碰撞预示模型说明几何规划的性能。表明遵循几何规划形式的超高速碰撞模型,可以进行综合非线性设计优化。  相似文献   

19.
An improved method of analysis of low-frequency wave processes in the interplanetary plasma using the results of multi-satellite measurements is presented. The new method develops the phase difference method and is distinguished by the fact that it allows one to analyze wavelengths several times shorter than the mean separation between spacecraft that perform the measurements. Its capabilities and the feasibility of analyzing events in different regions where spacecraft plasma measurements are undertaken are demonstrated using several examples of dispersion functions obtained by this method from the results of processing the magnetic field measurements on four spacecraft of the Cluster mission. The remarkable role played by ion-cyclotron oscillations in the outer magnetosphere cusp region is demonstrated, which manifests itself in wave generation and nonlinear structure formation.  相似文献   

20.
Materials on experimental studies to determine the effect of thin condensate films of cesium (used as a model working medium for electric propulsion engines and some spacecraft power sources) on integral optical coefficients of spacecraft thermal control coatings are presented. A technique modified by the author and employing the regular thermal regime of a thin metal plate is used. Measurement results demonstrate that films with thicknesses of 100–1000 Å can seriously degrade the integral optical coefficients of thermal control coatings and thus disturb the heat balance of some spacecraft systems.  相似文献   

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