民用飞机舱门通风口机构的设计与研究

通风口机构作为常见的增压预防措施,阻止飞机在舱门未完全关闭、上闩、上锁情况下增压到不安全水平,有效监控了舱门关闭状态,提升了飞机安全性。针对通风口机构常用的凸轮和四杆机构,结合成熟设计实例提出凸轮和四杆机构的设计要点,介绍有效通风面积计算方法,阐述通风口机构的设计原理。     

一种用于移动机器人的多段变形轮

变形车轮是提升轮式移动机器人在严苛地形越障能力的有效方案。然而传统单构型变形轮仅能适应特定路面环境,不能同时满足多种路面环境。利用一种平面多边形机构,将已有研究的轮式、扩展式和轮腿式构型相结合,提出了4种多段变形轮机构。同时,比较各构型的优缺点并针对较优方案进行杆长优化,提出相应的设计方法。根据不同路面情况,通过轮形间的有效切换,使得轮式移动机构在越障能力得到提升的同时,还能保证机构对不同种类地形的适应能力,达到提升机构通用性的目的。      

三轴稳定通信卫星在地球搜索模式下的陀螺标定

本文介绍三轴稳定通信卫星在转移轨道远地点点火前，在地球搜索模式下的陀螺标定方法和计算公式。此种陀螺标定需进行两次姿态机动，利用太阳敏感器和速率积分陀螺遥测数据标定陀螺的常值漂移。     

机器人典型平衡系统的研究

以关节型机器人典型的弹簧式平衡系统作为研究对象,探讨了它的计算模型与优化设计方法,并用实例进行了计算。     

Machinability of γ-TiAl: A review

Owing to its outstanding mechanical properties, γ-TiAl is desirable materials for crossgeneration aero-engines. Nearly 70 years of exploration have made it into the initial application.However, the intrinsic brittleness of γ-TiAl is still a critical obstacle to its large-scale applications.In this context, researchers have made many attempts to study the machinability of γ-TiAl. At present, existing relevant reviews have mostly discussed the processing methods of γ-TiAl. Hence, there is still a ...     

Combustion mechanism of fluorinated organic compound-modified nano-aluminum composite particles: Towards experimental and theoretical investigations

Fluorinated Organic Compounds (FOCs) are commonly used as modifiers for Aluminum (Al) powder to improve its ignition, combustion, and agglomeration characteristics. However, the effects of FOCs on combustion and inhibition mechanisms of agglomeration of Al powder are not well understood. In this paper, based on the experimental study of Fluorinated Graphite (FG)-modified Al matrix composite particles, the combustion and aggregation inhibition mechanisms of FOCs on Al particles were studied by the quantum chemical calculation at B3LYP/6-311+G(d,P) and G3//B3LYP/6-311+G(d,p) levels. The flame behavior and single particle burning behavior of FG-modified samples were compared through ignition experiments, and the characteristic spectra of Al related oxides of different samples in the initial ignition stage were captured. It is found that FG increases the burning intensity of Al composite samples significantly, while it decreases the emission intensity of Al secondary oxides. Quantum chemical calculation results show that the thermal decomposition intermediates of FOCs, namely C₂F₄, can react with AlO and Al₂O, which weakens the characteristic emission intensity of AlO and Al₂O in the sample, and thus inhibits the formation of Al₂O₃ in the combustion process. These results contribute to enriching the combustion dynamics model of Al-FOCs reaction system.     

统一建模语言UML及其应用

UML是面向对象的统一建模语言，是面向对象领域的重要成果。它的内容包括UML语义和UML表示法两个部分。本文简要介绍了UML语义，表示法的内容，并总结了它在某些重要领域的应用。     

导弹电液伺服机构的终端滑模控制研究

针对导弹电液伺服机构的调节控制,设计了一种终端滑模控制方案。采用特殊的终端滑模切换面及相应的控制策略,使系统在有限时间内收敛至终端滑模面。当系统到达终端滑模面后保证系统的状态保持在终端滑模面上,并于有限时间内收敛于平衡点附近的邻域内。仿真结果验证了该方法的有效性和分析的正确性。     

一种驱动扫描镜扫描运动的方法

文章提出了一种扫描镜扫描运动的驱动方法——基于凸轮匀速旋转驱动扫描镜的方法，推导了一种扫描镜的扫描运动规律方程和凸轮轮廓曲线方程，并对其进行了仿真。结果表明：该方法具有控制简单、扫描重复性较好的优点，能够满足某些光机扫描相机的要求，应用前景较好。     

星载天线双轴定位机构指向精度分析

以星载天线双轴定位机构为对象,分析了其指向精度的影响因素,从传动误差、测量误差、安装误差以及热变形误差等方面,研究了各项精度影响因素的分析模型和计算方法,建立了指向精度的分析模型,并以某一天线双轴定位机构为例进行指向精度分析。