深空探测航天器巡航段自主导航方法研究

对深空探测航天器自主导航方法进行了研究。为了应对深空探测中航天器轨道动力学模型的误差，在分光计测量航天器相对于太阳径向速度基础上，引入了小行星的视线矢量测量。通过最小二乘法计算出由小行星视线矢量所得到的位置信息，采用改进的信息融合方法修正扩展卡尔曼滤波中不精确的动力学模型造成的状态估计误差。同时计算了模型的能观度，对模型的可观性进行了分析。最后对算法进行了仿真分析，仿真结果表明，该算法对动力学模型的依赖性明显低于其他算法，在相同模型精度下，可获得更好的滤波精度。     

空间探测磁强计安装部件的力学特性分析

对某深空探测器中的有效载荷-高精度磁强计的安装部件进行了有限元分析,分别获取了磁强计安装部件在升空过程中承受40g加速度冲击载荷以及-180～75℃的极限温度情况下,在x,y,z方向上的最大应力和最大位移,给出了由于磁强计安装部件的变形而导致的三个探头在x,y,z方向上的偏转角度,采用扫频实验法分析了磁强计安装部件的频谱特性,为空间探测磁强计的设计提供了依据.     

基于单应视差的月面着陆区离面测量及平坦性分析

文章针对月球探测器的软着陆,提出了基于由平面诱导的单应视差的月面着陆区离面距离测量及平坦性分析方法.对于特征点分布不均匀情况,采用邻近特征点内插方法在全图强制性近似均匀选择点云作为兴趣点,用基于极线约束和单应约束融合的方法匹配纹理不丰富的兴趣点.使用由平面诱导的单应视差计算兴趣点的离面距离,以离面距离的最大值、绝对值的...     

空间探索用梯度密度气凝胶的合成与应用进展

气凝胶是空间探索领域的关键功能材料.系统介绍了单一密度气凝胶和梯度密度气凝胶材料的分类、合成方法、复合工艺、特殊性能及其在空间探索领域的应用.其中,梯度密度气凝胶材料的合成是国际上的技术难点,笔者结合自身研究将其复合方式分为早期方法、分层粘贴法、逐层凝胶法和梯度溶胶共凝胶法,揭示了梯度气凝胶应遵循由单位深度的低差异到高...     

A multiple-rendezvous,sample-return mission to two near-Earth asteroids

We propose a dual-rendezvous mission, targeting near-Earth asteroids, including sample-return. The mission, Asteroid Sampling Mission (ASM), consists of two parts: (i) flyby and remote sensing of a Q-type asteroid, and (ii) sampling of a V-type asteroid. The targeted undifferentiated Q-type are found mainly in the near-Earth space, and to this date have not been the target of a space mission. We have chosen, for our sampling target, an asteroid from the basaltic class (V-type), as asteroids in this class exhibit spectral signatures that resemble those of the well-studied Howardite–Eucrite–Diogenite (HED) meteorite suite. With this mission, we expect to answer specific questions about the links between differentiated meteorites and asteroids, as well as gain further insight into the broader issues of early Solar System (SS) evolution and the formation of terrestrial planets. To achieve the mission, we designed a spacecraft with a dry mass of less than 3 tonnes that uses electric propulsion with a solar-electric power supply of 15 kW at 1 Astronomical Unit (AU). The mission includes a series of remote sensing instruments, envisages landing of the whole spacecraft on the sampling target, and employs an innovative sampling mechanism. Launch is foreseen to occur in 2018, as the designed timetable, and the mission would last about 10 years, bringing back a 150 g subsurface sample within a small re-entry capsule. This paper is a work presented at the 2008 Summer School Alpbach,“Sample return from the Moon, asteroids and comets” organized by the Aeronautics and Space Agency of the Austrian Research Promotion Agency. It is co-sponsored by ESA and the national space authorities of its Member and Co-operating States, with the support of the International Space Science Institute and Austrospace.     

月球探测技术--发展历程和特点

介绍了人类发射月球探测器进行的主要探月活动以及月球探测技术的发展和演变。分析了月球探测轨道设计与地球卫星的区别 ,给出了一些最基本的设计原则。最后 ,对探测器总体系统设计中的构型技术和各分系统的特点及其设计要求作了描述     

月球采样机械臂系统设计及试验验证

在对月球采样返回任务需求及探测器系统任务剖面进行分析的基础上，设计并研制了一种轻量化、大负载、高精度、宽采样范围月球采样机械臂系统。该系统主要由4自由度机械臂及两种不同采样形式的末端采样器组成，可对不同指定区域浅层月壤进行铲、挖、浅钻等多形式采集。在综合考虑机械臂系统器上布局的基础上，基于运动学模型对采样机械臂的可达采样区域进行仿真分析，提出采样机械臂月面采样策略。基于等尺寸着陆器模拟平台，开展了针对3种不同密实度模拟月壤的采样试验，采样试验结果表明在可达采样空间内，采样机械臂对不同密实度月壤均具有较好的适应性，最大采样深度可达30 mm，最大单次采样量可达270 g，单次采样时间小于2 min。     

A BRIEF INTRODUCTION TO GEOSPACE DOUBLE STAR PROGRAM

The Geospace Double Star Exploration Project (DSP) contains two small satel lites operating in the near-earth equatorial and polar regions respectively. The tasks of DSP are: (1) to provide high-resolution field, particle and wave mea surements in several important near-earth active regions which have not been covered by existing ISTP missions, such as the near-earth plasma sheet and its boundary layer, the ring current, the radiation belts, the dayside magnetopause boundary layer, and the polar region; (2) to investigate he trigger mechanisms of magnetic storms, magnetospheric substorms, and magnetospheric particle storms, as well as the responses of geospace storms to solar activities and in terplanetary disturbances; (3) to set up the models describing the spatial and temporal variations of the near-earth space environment.To complete the mission, there are eight instruments on board the equatorial satellite and the polar satellite, respectively. The orbit of the equatorial satellite is proposed with a perigee at 550km and an apogee at 60 000km, and the inclination is about 28.5°; while the orbit of the polar satellite with a perigee at 700 km and an apogee at 40 000 km, as well as an inclination about 90°. The equatorial and polar satellites are planed to be launched into orbits in June 2003 and December 2003 respectively to take coordinating measurements with Cluster Ⅱ and other missions.     

浅谈中小企业如何引进和留住人才

作为资本有限的中小企业,不可能拿出大笔资金用于培训和招揽人才,但作为中小企业的经营者,在头脑中必须要有人才第一的观念,想尽一切办法去引进人才,留住人才,只有这样才能更好地适应新环境,促进新发展.     

密闭容器试验用人体代谢模拟装置

文章简要介绍了人体代谢地面模拟装置的原理、结构组成和应用结果。为在密闭容器中进行地面模拟试验,考核产品性能提供了一个较为可靠而全面的模拟环境。