双轴滚弯成形机成形过程与设计

通过分析板料双轴滚弯成形的变形机理，提出双轴滚弯成形有关参数的确定方法与滚轴设计的原则。     

在塑料模中应用液压抽芯机构

本文介绍了液压缸在塑料模抽芯机构中的应用，论述了液压缸的选用、与型芯的连接形式。固定、及如何对液压缸提供液压油等液压缸使用的方法及应该注意的问题。     

基于动力学模型的飞机大部件调姿轨迹规划

为了提高飞机调姿的运动安全并减小在误差敏感方向的冲击,采用Newton-Euler方法构建了调姿系统的动力学模型,以实现调姿轨迹的优化。该动力学模型综合考虑了支撑杆变形、驱动丝杆变形及运动误差的影响,可对比不同轨迹时部件运动全过程的运动学特性,实现多目标多约束条件下的轨迹优化。为了提高计算效率,提出了一种类间可分性最优的自适应核主成分算法进行特征提取,并结合模式识别中的自动分类方法,预判可行轨迹的性能,控制搜索范围,减少寻优过程中的计算量。以某型数控定位系统为例,在对150条可行调姿轨迹进行评价和优选后,大部件调姿过程的最大平动速度小于20mm/s,调姿结束时的最大角速度小于0.1rad/s,说明了该方法的可行性和有效性。     

弹射座椅某型机构撞针组件疑似裂纹故障探析

介绍了火箭弹射座椅某型机构撞针组件功能,对故障零件进行主要尺寸检查、试打火试验,并在体视显微镜、金相显微镜下进行了观察、维氏硬度检测等理化分析,最终确定了故障形成的原因及预防措施,可有效避免此类故障现象的重复发生。     

AGV技术发展综述

AGV是现代自动化物流系统中的关键设备之一,它以电池为动力,装备有电磁或光学等自动导引装置,能够独立自动寻址,并通过计算机系统控制完成无人驾驶作业.本文总结概括了AGV的发展概况,介绍了AGV的工作原理和应用领域,论述了AGV的关键技术及最新技术成果,为今后进一步设计出更好的AGV提供了参考.     

基于微分进化算法的深空小推力轨道优化设计

针对多目标多任务的深空探测轨道优化设计问题,基于以太阳为主引力体的二体模型,采用电推进小推力系统,提出了将目标行星的探测方式、探测顺序、发射窗口同时进行全局优化的解决方案.依此建立小推力轨道优化设计算法模型,利用微分进化算法进行全局一体化优化设计,得出多目标多任务的一体化深空探测轨道.通过与相同条件下其他设计方法的结果比对分析得出：基于小推力推进方式并采用微分进化算法进行优化的轨道优化设计方案,在多目标多任务深空轨道一体化设计问题上具有可行性及应用价值.     

A novel testability model for health management of heading attitude system

Prognostics and health management (PHM) is very important to guarantee the reliability and safety of aerospace systems, and sensing and test are the precondition of PHM. Integrating design for testability into early design stage of system early design stage is deemed as a fundamental way to improve PHM performance, and testability model is the base of testability analysis and design. This paper discusses a hierarchical model-based approach to testability modeling and analysis for heading attitude system health management. Quantified directed graph, of which the nodes represent components and tests and the directed edges represent fault propagation paths, is used to describe fault-test dependency, and quantitative testability information is assigned to nodes and directed edges. The fault dependencies between nodes can be obtained by functional fault analysis methodology that captures the physical architecture and material flows such as energy, heat, data, and so on. By incorporating physics of failure models into component, the dynamic process of a failing or degrading component can be projected onto system behavior, i.e., system symptoms. Then, the analysis of extended failure modes, mechanisms and effects is utilized to construct fault evolution-test dependency. Using this integrated model, the designers and system analysts can assess the test suite’s fault detectability, fault isolability and fault predictability. And heading attitude system application results show that the proposed model can support testability analysis and design for PHM very well.     

高校师德建设实践探索——以西安航空学院为例

师德建设是高校师资建设的重要内容。以西安航空学院已开展的工作为基础,从加强思想理论建设,建立完善各项相关规章制度,创建学习型组织等方面出发,探索构建高校师德建设的长效机制,推进高校师德建设向纵深方向发展。     

微型扑翼飞行器扑动机构相关研究进展

微型扑翼飞行器(FMAV)具有独特的外形和飞行优势,具有重要的军事和民用价值。扑动机构是微型扑翼飞行器实现能量转换和机翼仿生运动的核心部件,是扑翼飞行器研究中极其重要的一环。阐述了扑动机构仿生规律实现、设计方法的最新进展,同时就设计中的关键技术进行了评述,主要为:仿生扑动规律的实现;提高系统效率的机构匹配设计方法;扑动机构的发展趋势。     

Reliability evaluation of avionics system with imperfect fault coverage and propagated failure mechanisms

Fault tolerance designs are essential techniques for systems that require high levels of reliability, such as aircraft or spacecraft control system. Imperfect Fault Coverage (IFC) may lead to the failure of a system or subsystem even with adequate redundancy. Previous studies of IFC mostly concentrated on evaluating Coverage Factor (CF), whereas the system failure behaviors with IFC have rarely been involved. Failures that occur in low-layer may be covered by high-layer. However, if the coverage is imperfect, uncovered failure will have functional and physical impact on the system behavior. In this thesis, the failure behavior and reliability of IFC of multi-layer systems are studied and a Binary Decision Diagram (BDD)-based modeling and simulation method are proposed to evaluate system reliability. As a case, the failure behavior of an aero engine electronic controller with IFC is studied. The results show that the IFC may impact system behavior without taking the IFC into account, the system maintenance intervals may reduce, and thus the maintenance costs will increase.