ANSYS在电连接器温升分析中的应用

对于玻璃封接电连接器,由于接触件材料的电阻率较大,在使用时大量发热而导致的温升,可能会引起电连接器电气性能的大幅下降,甚至可能导致电连接器的功能失效.所以能够准确地计算出电连接器的温升值,对提高电连接器的可靠性是至关重要的.使用相关的计算公式进行理论计算,无法获得准确的电连接器的温升值.通过有限元分析软件ANSYS对电连接器进行有限元分析计算,将更为准确地计算出电连接器的温升,增加设计的可靠性.     

航天电连接器分离拉力测试系统设计

针对航天电连接器在出厂前需进行分离测试的情况,以JF2-126TD航天电连接器为研究对象设计了一种航天电连接器分离拉力测试系统,并对测试系统中硬件及软件技术进行研究.系统主要利用拉力传感器和数据采集卡获得电连接器分离瞬间的拉力值,通过所测数据与标准值的比较来判断航天电连接器的分离是否合格.     

基于间歇故障特征分析的航空电连接器故障预测软件设计与实现

针对航空电连接器间歇故障的评估与故障预测开展工作,介绍了间歇故障内涵与动态特征,提取了间歇故障广义强度作为状态评估与故障预测的评估指标,基于该特征开发了间歇故障状态评估与故障预测软件,并在电连接器案例上进行了实现与验证.测试表明,该软件能够有效评估电连接器的使用状态,并对当前状态下的剩余使用寿命进行预测,可以应用于航空...     

载人航天器电测自动化程序设计及应用

针对现有载人航天器电测过程不能流程化、自动化程控,消耗了相当多的人力资源和时间成本的问题,设计了载人航天器自动化测试程序。通过对自动化测试程序的格式、功能、处理流程进行分析和设计,为航天器电测提供基础数据资源,实现了航天器电测全周期自动化、流程化,能够适应不同系列载人航天器电测,有效减少测试人员的手动操作及岗位人员数量,提高了测试效率,满足高强度的地面测试,高效完成高密度的载人航天器发射任务。     

基于性能退化分析的电连接器可靠性评估

某型电连接器具有寿命长、可靠性高的特点,传统的基于失效寿命数据的可靠性评估方法行不通。提出了基于性能退化分析的可靠性评估方法,给出了进行评估的一般步骤,并以温度为加速应力设计了该型电连接器的加速退化试验。分析了电连接器的接触失效机理,进而推导出退化模型,估计出了样品的伪寿命值。利用Anderson-Darling统计量确定寿命分布类型为对数正态分布,对寿命分布函数和Arrhenius加速方程的参数值进行了极大似然估计,推导出了该型电连接器在工作温度下的可靠度函数,得出t0.9为244 240h。     

基于OBD协议的Android平台汽车虚拟仪表设计

提出了一种基于OBD协议的Android平台汽车虚拟仪表设计方法.该装置以连接器硬件和解析OBD数据软件为核心,连接器硬件读取OBD接口实时数据,软件解析相关参数值,最后在Android平台设备上进行图形化虚拟仪表显示.在分析OBD协议关键技术后,具体阐述了Android SDK开发环境下软件的设计方案.按该方案设计的...     

卫星供配电测试设备电连接器的检测方法

卫星供配电测试设备上有许多外观完全相同的电连接器,为了防止仅靠人为主观识别而导致电连接器插错,文章提出一种全新的、客观的检测方法;通过使用电连接器上未使用的悬空接点,将其与电源、指示灯和开关等元器件连接,形成闭合检测电路;当供配电测试电缆连接正确时,相应状态指示灯亮;否则,指示灯状态不正确;检测电路可避免电连接器错插、漏插和插接不到位的问题,提高卫星综合测试的安全性和可靠性;该设计已成功应用于多套地面供配电测试设备,并经过多颗卫星综合测试和发射任务的检验.     

支承舱减振性能分析

支承舱是运载火箭与航天器之间的重要连接结构,支承舱的振动特性是力学环境设计需要考虑的因素之一.本文从振动环境控制的角度进行支承舱结构动力学分析,阐述了一种基于支承舱振动特性研究的改善航天器力学环境的方法.在有限元建模过程中,引入了材料级性能试验.计算并比较了不同材料支承舱结构对航天器振动环境的作用,比较了连接面形式对振动环境的影响.基于分析结果给出了进一步研究的建议.     

低地球轨道航天器表面计算仿真

现代战争中航天器发挥着越来越重要的作用,同时航天器表面带电造成的危害也越来越明显.利用航天器与等离子体相互作用系统软件SPIS,采用PIC粒子分室法模拟计算了低轨道航天器表面及周围等离子体电位分布,航天器表面电子、离子及二次电子电荷密度分布,总结了航天器表面充电特性规律.结果表明:由于等离子体温度低、浓度高,航天器表面带电的电位较低;航天器运动方向前方,等离子体电位较高,在航天器运动方向背侧,等离子体电位较低;航天器周围的等离子体环境受尾迹效应的影响显著.仿真结果为航天器表面带电问题研究及航天器表面带电防护技术提供了技术参考.     

基于地平/恒星的GEO航天器自主导航仿真分析

研究航天器自主导航的优化测试问题,针对我国的GEO轨道及施加小推力后的航天器自主导航的研究却很少.对GEO轨道航天器来说,若其不在我国测站测控范围内,则难以实现轨道测控.针对上述问题,提出采用地平仪和星敏感器的自主导航方案.同时,考虑众多的GEO轨道航天器采用高比冲电推进技术用于位置保持以及寿命末期离轨,还研究了在沿轨道速度方向连续小推力作用期间的自主导航问题.通过仿真,结果表明采用地平仪和星敏感器以及推广卡尔曼滤波的自主导航方法可以适用于GEO轨道航天器.     

Intermittent failure detection of multiple electrical connectors in EWIS

Electrical wiring interconnection system (EWIS) of civil aircraft has been paid more attention in recent years, and intermittent failure detection of electrical connectors in EWIS is a challenging problem. This paper presents a sliding mode observer (SMO) approach for the intermittent failure detection of an aircraft electrical system with multiple connector failures. The mathematical model of the aircraft electrical system which contains multiple connector failures is established for transforming the intermittent failure detection problem into observer-based multiplicative faults isolation and estimation problems. A set of adaptive sliding mode observers are designed to locate the failure connectors preliminarily, the observers can adapt the unknown upper bound of the faults. Furthermore, a fault-reconstruction scheme applying the equivalent output error injection principle is proposed for fault estimation, where the characteristic parameters of connecters are reconstructed to identify the failures. Finally, a numerical example is provided to show the effectiveness of the proposed method.     

Eye movements and industrial inspection

A brief survey is given of the eye movement parameters which contribute to visual search strategies. The literature on eye movements and industrial inspection is reviewed and some recent studies carried out at the University of Birmingham into the eye movements underlying four inspection tasks are described. These tasks included the inspection of tin cans, electrical edge connectors, men's briefs and woven fabric.     

A novel approach to predict shear strength of tilted angle connectors using artificial intelligence techniques

Shear connectors play a prominent role in the design of steel-concrete composite systems. The behavior of shear connectors is generally determined through conducting push-out tests. However, these tests are costly and require plenty of time. As an alternative approach, soft computing (SC) can be used to eliminate the need for conducting push-out tests. This study aims to investigate the application of artificial intelligence (AI) techniques, as sub-branches of SC methods, in the behavior prediction of an innovative type of C-shaped shear connectors, called Tilted Angle Connectors. For this purpose, several push-out tests are conducted on these connectors and the required data for the AI models are collected. Then, an adaptive neuro-fuzzy inference system (ANFIS) is developed to identify the most influencing parameters on the shear strength of the tilted angle connectors. Totally, six different models are created based on the ANFIS results. Finally, AI techniques such as an artificial neural network (ANN), an extreme learning machine (ELM), and another ANFIS are employed to predict the shear strength of the connectors in each of the six models. The results of the paper show that slip is the most influential factor in the shear strength of tilted connectors and after that, the inclination angle is the most effective one. Moreover, it is deducted that considering only four parameters in the predictive models is enough to have a very accurate prediction. It is also demonstrated that ELM needs less time and it can reach slightly better performance indices than those of ANN and ANFIS.

     

软件复合连接件的形式化研究

基于构件的软件开发是软件开发的主流范型。构件通过连接件进行连接和交互。连接件是软件系统设计的一阶实体(First-class Entities),是决定软件系统功能和质量的重要因素。伴随软件系统和构件的规模及复杂程度日益增加,连接件变得愈加复杂和多样。因此,需要运用增量、合成的方法开发和支持复杂的连接件。本文提出一种根据已有连接件合成新连接件的形式化方法。该方法的特点是定义连接件合成的基本方式,即连接件运算符,组合运用连接件运算符合成复杂的连接件。并基于Wright连接件的形式化规约,给出了谊复合连接件形式化规约的生成算法。     

Design and UV-LIGA microfabrication of an electro-statically actuated power relay

A novel type of micro power relay has been designed and fabricated using UV-LIGA technology. The relay is based on electrostatic actuation and SU-8 was used as a functional material. The unique character of this novel power relay is that other than two SU-8 strips used both as electrical insulators mechanical connectors, all other components are made of metal or alloys. Because UV-LIGA technology has the advantages of broad material selection and the capability of making high aspect ratio microstructures, the technology is best suited for fabricating micro electro mechanical system power relays. A multi-step, multi-layer UV-LIGA process has been successfully developed and a prototype relay has been successfully fabricated.     

基于反射的连接器组合重用方法

连接器的建模与分析是复杂软件体系结构设计的一个重要问题.基于反射机制,提出了一种连接器的组合重用方法.为了支持这一想法,借用CSP进程间的运算,提出了连接器组合的一组元操作,并给出了组合连接器的CSP语义.该方法能为连接器提供一种增量式的开发方式,并且由于其严格的形式化基础,适合进行形式化分析和自动检查.     

连接件模型与分类研究

连接件对于基于软件体系结构的软件开发具有重要意义,该文根据连接件在软件体系结构中所承担的责任以及它对构件交互的支持,建立了连接件模型,进而根据软件开发中的连接实现以及软件体系结构风格的研究,对连接件进行了分类,包括过程调用等11类连接件,不同类型的连接件支持不同的实现映射和复用途径。     

BLDC motor speed control system fault diagnosis based on LRGF neural network and adaptive lifting scheme

Brushless DC (BLDC) machines are found increasing use in applications that demand high and rugged performance. In some critical circumstance, such as aerospace, the motor must be highly reliable. In this context, a novel model-based fault diagnosis system is developed for brushless DC motor speed control system. Under the consideration of the complexity of characterizing the dynamic of BLDC motor control system with analytic expression, a LRGF neural network (LRGFNN) with pole assignment technique is carried out for modeling the system. During the diagnosis process, fault signal of the motor is isolated with LRGFNN online. Meanwhile, adaptive lifting scheme and adaptive threshold method are presented for detecting the faults from the isolated fault signal under the existence of mechanical error and electrical error. The effectiveness of the diagnosis system is demonstrated in the simulation of electrical and mechanical fault in the motor. The detection of the incipient fault is also given.