面向空间电推力器的氙气供给系统发展综述及展望

在阐述氙气供给系统组成与分类基础上,将传统氙气供给系统和先进氙气供给系统按照机械减压型、开关控制型和比例控制型三种类型进行梳理,提炼了氙气供给系统中涉及到的关键技术,如建模与仿真技术、流体控制部件技术及系统集成技术,并对其研究现状进行了概述。对氙气供给系统的发展现状和发展趋势进行了总结,重点对国内外氙气供给技术的差距进行分析,给出了我国电推进氙气供给系统的发展建议。首次全面、系统地对面向空间电推力器的氙气供给系统进行综述、总结和展望,对于氙气供给技术的研究具有重要的参考价值。     

高精度非接触磁浮机构设计及其输出特性测试研究

为验证"双超"卫星地面试验系统与地面验证方案的合理性、可行性,针对"双超"卫星平台的核心部件非接触磁浮机构,提出了一种非接触磁浮机构磁钢匀强磁场、激励线圈拓扑结构及高精度程控精密功率放大器的多参数综合优化设计与测试方法。首先,通过选择适宜的磁钢材料和设计磁钢结构尺寸参数实现非接触磁浮机构磁钢磁场的均匀性;其次,通过激励线圈参数优化可降低输出力的波动;再次,通过驱动电路的优化设计可提升程控精密功率放大器的输出电流精度;最后,通过非接触磁浮机构的输出特性测试,验证了设计方法的有效性。该方法将"双超"平台的需求分解成磁浮机构各部分的设计指标,简化明确了设计思路,方案通过验证为下一步"双超"平台原理样机的设计及未来"双超"平台的工程应用提供了技术支撑。     

基于不同拓扑结构的十二相同步发电机整流电压波形分析

传统中小功率十二相整流型同步发电机电压等级较低,整流装置通常采用4套不控整流单元并联结构。随着舰船中压直流综合电力技术的发展,整流发电系统的容量和电压等级大幅提升,十二相整流单元采用两并两串的拓扑结构可以适应发电机绕组较高的电压设计值,同时整流端中性线可引出用于电力推进调速装置的均压控制。分析了两并两串拓扑结构的不同联接组合型式,重点对两种可行的拓扑结构下的直流侧电压波形进行了解析计算,并通过仿真与试验验证了理论分析的正确性,证明了(Y1//Y3)+(Y2//Y4)拓扑结构为最优组合方式,具有最佳的直流电压品质。     

TRIP2.0_SOLVER的开发与应用

本文介绍了“亚跨超CFD软件平台”2.0版本流场解算器部分(TRIP2.0_SOLVER)的开发工作和应用情况,重点是结构网格部分的开发工作,包括对接网格、拼接网格、重叠网格等多种网格拓扑结构。TRIP2.0_SOLVER采用有限体积法离散雷诺平均的N-S方程,数值模拟绕流飞行器的空间流场和飞行器的气动特性,本文从软件已经具备的基本功能,用户界面的开发、软件测试和和多种网格拓扑结构的应用等四个方面总结了亚跨超CFD软件平台流场解算器(TRIP2.0_SOLVER)的工作进展情况。     

直升机灭火瓶充填及导入设备的研制

直升机灭火瓶充填难,返厂修理周期长、费用高,运输安全隐患大等问题严重影响了飞行训练任务地完成。复合式充填工具及导入设备的成功研制可简化氮气及灭火剂的充填,安全实用,显著提高了维修功效。     

导航卫星原子钟舱温度控制方法及其验证

原子钟是导航卫星的重要组成部分,可为卫星系统提供高准确及高稳定度的时间频率源.原子钟工作性能与环境温度变化密切相关,为保证其在轨连续、稳定运行,热控系统需为其提供良好的工作温度环境.本文以某导航卫星原子钟舱温度控制为研究内容,给出原子钟舱热控设计方案、控制算法,并进行仿真分析和试验验证.在轨遥测数据表明,卫星原子钟舱热控方案和控制算法设计合理,仿真分析及试验结果有效,各原子钟在轨工作温度满足要求,原子钟温度稳定度满足并优于设计指标近一个数量级.     

CCD衬底反弹防护的工程实现

文章阐述了电荷耦合器件（CCD）衬底反弹问题产生的机理以及防护措施。针对高速驱动信号的工作特点和衬底反弹对CCD信号造成的影响,介绍并分析了波形化理论。理论分析表明,利用波形化理论能够对衬底反弹进行抑制,通过电路仿真和实际电路测试,验证了理论分析的正确性,为焦面驱动电路设计提供了一种新方法。     

宇航元器件应用验证系统工程研究

在调研国内外宇航元器件应用验证研究及工程实践的基础上,总结了我国宇航元器件应用验证的目标和特点,即以解决元器件宇航应用可用度评价并促进成熟应用为目标,具有多阶段、多领域、多目标、多任务和多参与方等特点。分析了应用验证的复杂性、层次性、整体性、环境适应性等复杂系统特性;在论证系统工程理论和方法指导宇航元器件应用验证研究适用性的基础上,建立了系统工程视角下的我国宇航元器件应用验证技术框架体系,凝练出一套集成的应用验证成果体系。应用验证工程实践表明,应用验证研究成果具备有效性和科学性,但仍需不断丰富和完善。     

Static Frame Model Validation with Small Samples Solution Using Improved Kernel Density Estimation and Confidence Level Method

An improved method using kernel density estimation (KDE) and confidence level is presented for model validation with small samples. Decision making is a challenging problem because of input uncertainty and only small samples can be used due to the high costs of experimental measurements. However, model validation provides more confidence for decision makers when improving prediction accuracy at the same time. The confidence level method is introduced and the optimum sample variance is determined using a new method in kernel density estimation to increase the credibility of model validation. As a numerical example, the static frame model validation challenge problem presented by Sandia National Laboratories has been chosen. The optimum bandwidth is selected in kernel density estimation in order to build the probability model based on the calibration data. The model assessment is achieved using validation and accreditation experimental data respectively based on the probability model. Finally, the target structure prediction is performed using validated model, which are consistent with the results obtained by other researchers. The results demonstrate that the method using the improved confidence level and kernel density estimation is an effective approach to solve the model validation problem with small samples.     

Investigation into Pilot Handling Qualities in Teleoperation Rendezvous and Docking with Time Delay

Teleoperation rendezvous and docking can be used as a backup for autonomous rendezvous and docking(RVD) for an unmanned spacecraft when the autonomous system is failure or for guiding the chaser docking with an uncooperative target.The theoretical model for analyzing the handling qualities in teleoperation RVD process is established based on the previous studies conducted by National Aeronautics and Space Administration(NASA).The predictive factor is introduced to describe the pilot’s predictive ability in the teleoperation tasks with time delay,which interrelates with the skills of a pilot and the predictive assist approach used in the tasks such as the predictive display method.Based on the semi-physical simulation system in our laboratory,900 experiments at two levels of time delay are carried out by 18 volunteers for validating the established model.The experimental results demonstrate the correctness of the theoretical model and indicate that a skilled pilot has a predictive ability of approximately 0.9 in teleoperation RVD tasks.The theoretical analysis shows that the handling qualities are greatly affected by the time delay and the predictive factor,and it is impossible to achieve a teleoperation RVD task for the skilled pilot when the time delay is larger than 9.0 s.