BPRT系统同步离合器试验台设计

设计了主要面向BPRT系统中的同步离合器接合动态性能的试验台。试验台采用电机调速、PLC数字控制及喷油强制润滑;PLC模块根据采集到的速度以及位置信号对变频电机进行调速,并通过人机交互界面对试验台进行实时监测。试验台结构简单,操作便捷,调速范围广。根据实验数据及同步离合器的啮合动态原理分析可知,该试验台能较好地满足同步离合器在不同速度下的性能试验,对同步离合器的设计及生产制造具有显著的工程意义。     

基于PLC跌落式冲击试验监控系统安全设计

文章从冲击试验台工作过程、监控系统方案、安全性措施、通讯四个方面系统地阐述了跌落式冲击试验监控系统的设计,重点从系统通讯安全性和命令执行安全性两个方面进行设计和阐述,最终设计实现整个监控系统的安全可靠运行。整个监控系统使用VB和PLC作为开发工具,采用多级安全保护、具有多种设定运行模式并能全部安全正确的自动完成。在GTSHOCK120V跌落式冲击试验台进行试验证明,系统功能和性能均非常良好。     

基于PLC的液压扩张器试验台设计

为提高液压扩张器产品的安全性和稳定性,设计了一种基于PLC的液压加载试验台。该试验台可对扩张器进行疲劳、过载等性能试验,控制系统利用上位机设置参数和显示数据,并通过PLC和传感器组成的闭环负反馈系统对试验台加载压力进行PID调节,使扩张器压力稳定保持在试验条件下。数据表明试验台能够准确调节负载,使扩张器压力稳定工作在试验要求范围内。试验台不仅对产品的设计、开发和改进提供依据,也对恒定加载的试验设备开发有一定的指导意义。     

开放式电梯限速器性能试验台设计

本文主要对开放式电梯限速器性能试验台设计进行了分析,其中试验台为机电一体自动化设备,满足额定速度10m/s的电梯限速器的动作速度特性和振动特性试验。试验台可自动采集、显示限速器运行速度曲线,能够记录并保存设备运行状态等数据,同时进行数据存储,查询。设备由伺服系统和PLC控制,按钮和上位机配合操作,使用方便。     

基于PLC和触摸屏的液压缸耐久性试验异常监控系统设计

液压缸耐久性试验中液压缸的运行次数多、时间久,且对液压缸自身有一定的破坏性。因此,在无值守人员的情况下,试验过程中试验台出现异常情况时,需要试验台的控制系统能够自我识别异常并做出紧急处理。该文结合本公司的液压缸耐久性试验,基于PLC和触摸屏控制系统,从液压缸的运行状态、液压缸进出油口的油压、液压油温度三个方面阐述试验台异常监控系统的设计。     

液压阀试验台计算机控制系统

针对传统的液压阀试验台精度不高、自动化程度低等缺点,采用电磁阀、西门子S7-200系列PLC和Visual Basic 6.0改进设计了煤矿液压支架用阀试验台,实现了试验控制和数据采集的自动化,提高了实验效率.其数据的采集和设备的控制由PLC等现场设备完成,VB则主要完成数据通信、网络管理、人机界面和数据处理等功能.     

组态软件WinCC在AGC缸测试系统中的应用

为某厂研制的AGC缸试验台,采用WinCC组态软件进行画面设计。介绍了自动监控系统的软硬件构成,分析了WinCC与PLC之间的通讯机制。画面程序实现了对测试过程中电流、电压等相关数据的显示,以及相关故障、报警信息的指示。主要阐述了利用组态软件WinCC设计监控系统的方法。     

OPC技术在液力变矩器性能试验台系统中的应用

为提高液力变矩器性能检测的效率,将计算机技术应用于液力变矩器试验台的控制系统中,构建了其硬件控制方案;并采用图形化编程语言LabVIEW作为上位机软件开发工具,结合西门子S7-300PLC实现了对检测液力变矩器性能试验过程的实时监控;同时研究了在LabVIEW中使用OPC技术与联网的PLC进行通讯以实现上位机对执行电机的控制.实践结果证明,该控制系统运行稳定、可靠,提高了变矩器性能检测的自动化程度,缩短了检测周期,提升了工作效率.     

减速齿轮箱试验台监控系统设计及实现

为提高减速齿轮箱试验台监控系统自动化程度和通用性,设计了基于Labview的减速齿轮箱试验台监控一体化系统。根据减速齿轮箱试验台系统总体结构,结合试验要求,完成了监控系统硬件选型,采用Labview开发了一套具备主电机控制、自动控制、数据保存和报警信息等功能的模块化监控软件,并对软件功能界面和实现进行详细介绍。经过长期试验和现场运行情况表明,该减速齿轮箱试验台监控系统稳定性好,自动化程度高,达到设计预期。     

变速箱疲劳试验台的研究与应用

主要介绍了变速箱疲劳试验台的组成及技术实现。该试验台能够进行手动、自动两种方式的试验,并且具有对多种类变速箱及分动器进行试验的能力,提高了试验台的通用性能。试验系统通过PLC对变频器的模拟量进行控制,实现对驱动和加载电机的变转速变转矩控制。通过模拟变速箱运行状况对变速箱进行加载,实现工控机对转速、转矩及油温信号等实时数据的采集、处理、显示和存储,并进行故障报警。该系统可实现对变速箱综合性能的检测,保障变速箱质量。     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.