立方体纳卫星的发展及其启示

介绍了立方体纳卫星的发展概况;对“震动卫星”、Cute系列、“加拿大先进纳太空实验”卫星和Coral卫星平台等典型项目进行了分析,重点对立方体纳卫星的任务、姿态与轨道控制、电源系统、通信系统、星载综合电子和可靠性等方面进行了总结。结合立方体纳卫星快速发展的原因,提出了以下建议：结合在轨服务、深空探测和新技术空间飞行演示试验等应用需求,发展微电子技术、微机电系统技术的航天应用、微卫星平台技术和标准化辅载荷发射接口技术。     

火星探测无动力借力飞行轨道研究

对无动力情形的借金星引力辅助变轨进行了研究,并完成了火星探测轨道的设计;首 先使用Jacobi积分得到了蒂塞朗准则,在利用速度矢量图对借力飞行轨道的特性进行分析后 ,得到了Williams提出的C3匹配法,证明了蒂塞朗准则和C3匹配的同一性;在 搜索借力飞行的可行性转移轨道中,采用C3匹配对借金星引力的火星探测轨道进行了 仿真,并对结果进行了分析,最后使用蒂塞朗准则对C3匹配的仿真结果进行了检验。     

月亮女神探月计划的有效载荷与科学探测综述

月亮女神探月计划根据科学目标的需求配置多波段成像仪、地形测绘相机、测月雷达、月球磁强计、高清电视摄像机等15台(套)有效载荷.文章阐述了有效载荷的基本原理、主要技术指标及其科学任务.通过1颗主探测器(Kaguya)和2颗子探测器(Rstar,Vstar)的相互配合以及精密测轨,获得了迄今最为精细的重力场分布数据,为研究...     

变推力月球软着陆制导优化研究

提出了一种新的使用变推力火箭发动机实现月球定点软着陆制导的优化方法.在软着陆加速度抛物线(即二次函数)变化的条件下,通过一组代数方程连接初始条件和终端条件,避免了求解两点边值问题的迭代计算.给出了瞬时位置速度状态参数以及需要推力加速度、推力和秒流量的计算公式,并通过调整总飞行时间和着陆点位置实现了燃料消耗最小的优化处理.算例结果证明了这种方法的可行性和有效性.     

月球测绘学分类及应用展望

根据月球测绘的研究现状及发展趋势,对月球测绘学的概念进行了溯源与拓展.在分析月球测绘学与地球测绘学主要差异基础上,从传统测绘学科分类角度出发,综合考虑月球测绘学特殊性,重新梳理出月球测绘学主要学科专业分类,并详细介绍了每个学科专业的定义及国内外研究现状,给出了月球测绘学的五个主要应用领域及其应用展望.我国应尽早开展月球...     

空间探测烧蚀防热材料应用及趋势

综述了国内外空间探测器烧蚀防热材料的种类及其应用情况,美国主要包括高密度酚醛/玻璃钢、蜂窝增强烧蚀防热材料、PICA及PICA-X以及高密度碳酚醛材料等,国内则主要包括酚醛/尼龙、蜂窝增强烧蚀防热材料和NF材料,介绍了这些材料所应用的探测器、气动加热环境、防热材料性能和防热结构成型技术。总结了美国空间探测防热材料研制中出现的两次烧蚀异常及导致的探测器选材变化,可见防热材料与热环境耦合关系复杂。同时介绍了我国针对防热材料抵御异常损伤开展的部分工作。最后对空间探测防热材料的应用与发展做出了展望。     

Star angle/ double-differenced pulse time of arrival integrated navigation method for Jupiter exploration

Pulsar navigation is a promising autonomous navigation system for spacecraft, which is applicable to the entire solar system. However, the pulsar’s directional error and the onboard clock error are two types of systematic errors that seriously reduce navigation accuracy. To solve this problem, a star angle/double-differenced pulse time of arrival(SA/DDTOA) integrated navigation method is proposed. Since measurements obtained by observing different pulsars contain the same clock errors, the measurements can be differed to eliminate the common clock error. Then, the pulsar-differenced measurements at neighbor filtering time can be differed to suppress the effect of the pulsar’s directional error on navigation precision. Star angle is used to obtain absolute navigation information, which denotes the angles between the light of sight of Jupiter and that of its background stars. Simulation results demonstrate that the proposed method can eliminate the influence of the onboard clock error and greatly weaken the effects of the pulsar’s directional error. The navigation accuracy is better than the traditional star angle/pulse time of arrival integrated navigation method and star angle/pulse time difference of arrival integrated navigation method. In addition, the navigation accuracy of the SA/DDTOA integrated navigation method is less affected by Jupiter’s ephemeris error. This work greatly reduces the influence of common systematic errors in pulsar navigation on navigation accuracy.     

多视角多尺度陨石坑特征检测识别方法

针对序列图像间视角尺度变化大带来的特征无法检测和识别效率低等问题，提出了多视角多尺度陨石坑特征检测识别方法。基于明暗区域信息和形态学处理实现陨石坑图像特征边缘粗提取，利用快速傅里叶变换计算模板与图像特征的匹配度，从而实现图像特征所在区域粗定位。在此基础上，通过引入惯性测量信息计算图像间重叠面积，更新模板形状，并预测搜索区域，解决了序列图像间视角尺度变换及信息冗余带来的特征无法检测和识别效率低的困难，最终在单一陨石坑区域内实现其精细检测。     

Effect of mixing section configurations on combustion efflciency of Mg-CO2 Martian ramjet

Experiments were conducted to determine the effects of the mixing section configurations on the Mg-CO₂ Martian ramjet combustion efficiency. It was carried out at a mainstream mass flow rate of 110 g/s and a temperature of 810 K. The chamber pressure was measured under different configurations and Oxidizer to Fuel(O/F) ratios. Results showed that the engine achieved self-sustaining combustion and worked stably during experiments. The pre-combustion chamber is needed to increase the co...     

Technical evaluation of additive manufacturing technologies for in-situ fabrication with lunar regolith

In-Situ Fabrication and Repair can significantly reduce the construction cost of a permanent Moon base by using additive manufacturing (AM) and exploiting local resources instead of bringing all the required materials from Earth. In this article, we evaluate alternative additive manufacturing technologies for building a lunar base and maintaining it across its lifecycle. We compare alternative 3D-printing techniques, already tested for manufacturing with simulants of lunar regolith, using energy, Earth-deliverables consumption, and compressive strength of the produced samples as figures of merit. Based on our analysis, we conclude that Cement Contour Crafting and Stereo-lithography AM techniques are the most promising solutions for the construction of outdoor lunar infrastructure and small precise parts and instruments, respectively.