用于叶轮机械流场计算的交错网格有限体积法

在对各种交错网格离散格式的奇偶不耦合数值误差进行了详细的傅里叶分析和比较后,采用一种紧致的交错网格有限体积法将纳维-斯托克斯方程和k-ε湍流模型方程紧密的耦合在一起求解,发展了一套三维定常流程序.通过对NASA Rotor 67设计和非设计工况内部流场的数值模拟结果与实验的比较、分析,初步验证了程序的准确性和可靠性.      

一种三维激光扫描系统的设计及参数标定

基于三维激光扫描系统的移动机器人动态环境地图构建技术是机器人智能感知技术的重要组成部分,而三维激光扫描系统的设计及标定技术对于地图构建的精度有决定性的影响。针对应用于小型移动机器人的三维激光扫描系统低成本、小型化的需求,设计了一套由高精度旋转云台和小型二维激光测距传感器组成的三维激光扫描系统,并提出了一种新的系统参数标定方法以提高三维扫描测量的准确度。该方法使用镂空圆孔标定板作为标定对象以完成对三维扫描特征自动准确获取,并根据非线性最小二乘法对三维激光扫描系统的参数进行优化计算。实验结果表明,所设计的三维激光扫描系统能够准确地测量周围环境的三维信息,实现了以低成本获得高质量环境建模的三维扫描数据技术。      

基于二维连通图的无人机快速三维路径规划

针对复杂真实环境下无人机三维路径规划解算速度慢的问题，提出一种基于二维连通图的快速三维路径规划方法。首先解析真实地理环境的地形特征和建筑要素，构建基于数字高程模型(DEM)的多层次等效三维数字地图；在此基础上，经过无人机可行空域到二维连通图的转化、连通图中的路径规划及路径的三维化与优化，快速获得一条可执行的三维路径。针对连通图中的全局路径规划，设计了一种基于步长地图的变步长稀疏A^*算法，在保证路径质量的同时有效降低路径搜索的时间；针对连通图中的局部路径规划，提出一种基于障碍预测的随机路标图(PRM)实时路径重规划算法，以满足无人机的实时性避障需求。分别在山地环境和城市环境中进行仿真飞行，结果表明：所提方法能够有效降低三维路径规划的解算难度，在短时间内完成复杂环境下不同尺度和需求的路径规划，全局路径规划算法同比三维A^*算法和基于二维连通图的二维A^*算法搜索时间分别降低了99%和95%，局部路径重规划算法能够在1 s的单次采样周期内完成路径重规划，实时躲避未知障碍物，保证飞行过程的安全。     

基于机器视觉的轻型梁三维振动测量方法

振动测量是状态检测和故障诊断的方法之一，针对传统接触式测量方法中存在负载效应等问题，对基于机器视觉的三维振动测量方法进行了研究。首先，基于视频相位的二维振动测量方法，提取出相机所采集图像中被测目标的二维振动数据。然后，在二维振动测量方法的基础上，结合双目立体视觉，设计了一种基于机器视觉的三维振动测量方法。最后，进行了悬臂梁的振动测量实验。结果表明:所提方法可以实现无接触和无标记的振动测量，并能准确测量出三维的振动信息。      

通信卫星成本和重量估算的模化方法——一种帮助系统工程师权衡空间通信系统(成本—重量)/性能的计算机模化程序

通信卫星系统设计的初期,设计师不仅应当满足用户提出的各种要求,而且必需协调不同要求所产生的种种矛盾。因此,要经常进行性能要求(如信道数量)和限制条件(如运载能力、投资总额)之间的权衡,以便确定系统的初步轮廓,作为深入分析和设计的基础。加拿大宇航有限公司(CAL)提出了一种估算通信卫星成本和重量的新的模化计算机程序(简称为CAL模化程序),帮助系统工程师进行设计权衡。     

一种通用红外成像跟踪实验装置的设计

介绍了一种先进的红外成像跟踪实验装置的研究与设计实现,给出了系统结构、主要性能参数、跟踪算法设计以及试验结果.在成功设计含双微处理机的并行图像识别跟踪器基础上,针对不同类型的目标开发了不同的跟踪算法以及噪声生成算法程序.该实验装置能模拟多种红外跟踪系统,可安装在直升机上对多种目标进行搜索、捕获和跟踪试验,试验恶劣天气、烟雾以及改变空间分辨率等系统参数对图像识别与跟踪的影响,也可进行各种干扰试验,以检查干扰效果.经试验验证,该系统有很好的应用效果.这些试验为模拟实验的研究提供大量原始素材,将为红外图像跟踪系统的设计和使用提供重要数据.      

电动静液作动器热力学建模方法及油液温升规律

电动静液作动器（EHA）是多电飞机关键子系统之一,其高度集成设计在减小体积和质量的同时,大幅降低换热能力,导致EHA油液温度过高、功能丧失。针对目前EHA一维热力学建模不足问题,以油冷电机驱动的EHA为研究对象,提出EHA的“三维+一维+三维”的热力学建模方法。首先,分析EHA能量转换及传递规律,探究EHA热能产生和扩散途径,在考虑参数时变基础上提出EHA的“三维+一维+三维”热力学建模方法;其次,基于ANSYS平台建立EHA电机生热和壳体对流换热的三维热力学模型;然后,建立柱塞泵、液压缸、阀和增压油箱等一维热力学模型;最后,在AMESim平台上搭建EHA的“三维+一维+三维”的热力学模型。仿真和实验验证了EHA的“三维+一维+三维”热力学建模方法的正确性,揭示了EHA油液温升规律,为EHA的热设计提供了理论依据。      

一种以二极管为基础的94GHz单六端口反射计

本文描述了一种由带硅肖特基二极管检波器的WR-10波导构成的单六端口反射计的设计考虑,给出了测量结果,讨论了不同类型功率检波器的交替使用方法以及六端口接头的设计准则,比较了两种校准程序的优点。在94GHz的测量结果表明,q点和额定反射系数为0.1 的滑动失配的估计值和实验值之间达到了良好的一致。     

航天工程系统集成模型和策略研究

系统集成是系统工程的重要组成部分,决定着大型工程系统的成败.航天工程是典型的大型工程系统,系统集成过程环节多且关系复杂,经常发生因系统集成不合理而导致整个工程计划延误或性能指标降低的情况,严重影响了工程效用的发挥.本文探讨了航天工程系统集成模型的建立和策略的设计;分析了系统集成的两种典型模型和策略;通过示例研究了航天工程系统集成模型的建立和策略的设计.      

基于MBSE的民用飞机功能架构设计方法

基于模型的系统工程（MBSE）理论越来越广泛地应用于民用飞机设计与功能需求分析领域。研究起始于基于用户需求的自顶向下的民机系统产品顶层用例,辨识相关关键子用例,进一步基于对象用例展开“需求—功能分析”,构建黑盒活动图、顺序图表达实现相关飞机级需求的黑盒功能流,从而明确系统接口和辨识子系统,构建经验证可靠的可进行逻辑仿真的黑盒状态机。在黑盒功能架构的基础上驱动基于人机交互系统模型仿真的民机功能架构“正向设计”过程,对黑盒进行解白,基于建模分析和数值仿真结果,构建实现相关飞机级需求的系统功能白盒架构的“正向设计”。为充分演示上述方法,选择了对民用飞机产品安全性具有关键影响的最后进近着陆场景用例作为案例模型。研究表明,基于MBSE的民用飞机功能架构设计方法充分保证了需求分析和功能架构设计的紧密结合,正向构建了以满足民机产品需求为导向的结构化系统设计方法。      

执行应允式卫星指令控制体制

针对现代卫星指令控制技术要求,在信息反馈校验指令控制方式基础上,本文提出了执行应允式卫星指令控制新体制,介绍了体制的系统模型、校验监督能力、概率分析方法和系统性能特点;提供了本体制应用价值的理论依据和工程设计计算、系统性能评价的方法。     

A novel system parameters design and performance analysis method for Distributed Satellite-borne SAR system

As a promising new technology emerged in recent years, the Distributed Satellite-borne SAR (DSS) system with Interferometric Synthetic Aperture Radar (InSAR) imaging capability has been recognized by the remote sensing community as an integrated part of the spaceborne earth observation system. However, most researches on DSS were focused on individual aspects of system design/analysis and data processing, while few studies have been dedicated to establishing a standard methodological framework for universal DSS system design. Aiming at this problem, the topics of DSS system error analysis and design method are investigated in this paper. Firstly, a rigorous error propagation model of height measurement is theoretically derived from the DSS InSAR imaging geometry, and the impact of each error sources in this model on the height measurement accuracy is analyzed individually. In particular, the baseline length and its measurement error in the InSAR imaging plane are identified as the dominant factors. Second, a new method for DSS system design is proposed based on our analyses with the error propagation model. This method consists of two important phases, namely collaboration design and monostatic design. The major objective of collaboration design is to determine the configuration and parameters for the coordination between satellites in the DSS system. Afterwards, the key parameters for single satellite and the payload are determined by the monostatic design. Thirdly, a system performance analysis method is developed to comprehensively evaluate the performance of the pre-designed DSS system. In the next section, a typical example of DSS system design is given to demonstrate the effectiveness of the proposed system design and analysis methods. The target DSS system has the same goal and hardware configuration as the TanDEM-X mission. Finally, the conclusion is drawn with our major findings are presented.     

归纳推理和归纳进程

分析了归纳推理与演绎推理的区别, 给出了归纳推理的形式化规则,定义了重构和归纳进程(序列)的概念.同时还给出了一个产生归纳序列的归纳过程模式,并证明:若已知模型M的全体实例集合ε_M,则可以从任一给定的理论出发, 使用此归纳过程模式所产生的所有归纳序列都收敛于同一极限,这个极限就是模型M的全部真语句. 这说明了归纳推理规则的合理性.     

信息传输卫星方案的综合和分析

本文提出一种用于信息传输卫星总体方案的设计方法,从分析对卫星任务的要求和约束出发,提出了总体方案的综合因素以综合各可替代方案。然后建立一个由总体设计要素和设计单元构成的二维总体方案设计模型用于对不同方案的分析。     

基于模型的民机验证需求捕获及应用技术

针对当前验证工作顶层规划性不强、研制单位与承试单位接口不清晰、验证活动充分性不确定等问题，基于系统工程的民机研制过程，结合验证场景建模，形成以验证需求为核心的验证工作技术流程。承接产品设计需求，开展验证场景利益关联方识别、验证场景活动建模及时序建模研究；定义验证需求的内涵要素，基于模型开展验证需求捕获，形成设计需求到验证方法到验证需求的映射追溯；在此基础上，研究基于验证场景模型的验证计划及验证程序定义方法。结合某型飞机起落架系统案例，形成一套从设计需求到验证需求再到验证程序的完整技术方法。所提技术方法能够充分保证从产品设计需求到验证活动开展的完整追溯，有效促进民机研制验证过程与产品研制有机融合，为民机研制早期对验证活动的规划提供重要借鉴。      

Generic procedure for designing and implementing plan management systems for space science missions operations

This paper is one of the components of a larger framework of activities whose purpose is to improve the performance and productivity of space mission systems, i.e. to increase both what can be achieved and the cost effectiveness of this achievement. Some of these activities introduced the concept of Functional Architecture Module (FAM); FAMs are basic blocks used to build the functional architecture of Plan Management Systems (PMS). They also highlighted the need to involve Science Operations Planning Expertise (SOPE) during the Mission Design Phase (MDP) in order to design and implement efficiently operation planning systems. We define SOPE as the expertise held by people who have both theoretical and practical experience in operations planning, in general, and in space science operations planning in particular. Using ESA’s methodology for studying and selecting science missions we also define the MDP as the combination of the Mission Assessment and Mission Definition Phases. However, there is no generic procedure on how to use FAMs efficiently and systematically, for each new mission, in order to analyse the cost and feasibility of new missions as well as to optimise the functional design of new PMS; the purpose of such a procedure is to build more rapidly and cheaply such PMS as well as to make the latter more reliable and cheaper to run. This is why the purpose of this paper is to provide an embryo of such a generic procedure and to show that the latter needs to be applied by people with SOPE during the MDP. The procedure described here proposes some initial guidelines to identify both the various possible high level functional scenarii, for a given set of possible requirements, and the information that needs to be associated with each scenario. It also introduces the concept of catalogue of generic functional scenarii of PMS for space science missions. The information associated with each catalogued scenarii will have been identified by the above procedure and will be relevant only for some specific mission requirements. In other words, each mission that shares the same type of requirements that lead to a list of specific catalogued scenarii can use this latter list of scenarii (regardless of whether the mission is a plasma, planetary, astronomy, etc. mission). The main advantages of such a catalogue are that it speeds-up the execution of the procedure and makes the latter more reliable. Ultimately, the information associated to each relevant scenario (from the catalogue or freshly generated by the procedure) will then be used by mission designers to make informed decisions, including the modification of the mission requirements, for any missions. In addition, to illustrate the use of such a procedure, the latter is applied to a case study, i.e. the Cross-Scale mission. One of the outcomes of this study is an initial set of generic functional scenarii. Finally, although border line with the above purpose of this paper, we also discuss multi-spacecraft specific issues and issues related to the on-board execution of the plan update system (PUS). In particular, we show that the operation planning cost of N spacecraft is not equal to N times the cost of 1 spacecraft and that on-board non-synchronised operation will not require inter-spacecraft communication. We also believe that on-board PUS should be made possible for all missions as a standard.     

无控固体火箭探空运载系统总体设计

由无控固体探空火箭和地面发射设备组成的运载系统是固体火箭探空系统的一个组成部分。文章介绍该运载系统在各研制阶段的设计内容,着重讨论总体方案选择的原则和总体参数设计的方法。