基于STM32的CAN总线测试平台设计

针对建筑电气与安防系统中不同波特率和不同协议的CAN总线网络节点,以STM32F103单片机为主控制器,设计了一种CAN总线测试平台。给出了该平台的硬件电路和软件设计方案。其中,硬件电路包括MCU控制模块、CAN总线接口模块、按键及开关模块、一键下载/串口通信模块与SWD调试模块等。软件部分包括波特率设置模块、CAN数据封装模块、串口/CAN转发模块、数据反射模块、灯光信号处理模块等。功能方面,该测试平台具有CAN总线信号反射、串口/CAN数据双向转发两种功能。经调试表明,该测试平台通讯可靠,灵活性高,可扩展空间大,达到预期设计目的。     

基于NPort串口服务器的座椅滑道装配线监控系统

为了解决座椅滑道装配线中各个独立工位的运行状态监控问题,采用了NPort串口服务器的形式进行各控制器的联网,介绍了串口服务器的发展过程、结构和设计原理,分析了滑道装配线的组成和装配工艺,分析了串口通讯时的通讯参数和自定通讯协议的构成,介绍了LabVIEW软件的功能和MX-Component模块的作用,提出了上位机监控软件的主体结构,设计的软件经过调试后能够稳定运行,实际使用结果表明,串口服务器可以很好地解决由独立工位构成的装配线中各控制器的联网监控问题。     

台达PLC与条码扫描装置的通讯

介绍了一种极具性价比且稳定可靠的串口通讯方式,利用台达可编程序控制器的自由通讯接口实现与串口设备的通讯。详细描述了台达PLC自由通讯口的通讯模式,给出了与条码扫描枪实现通讯的编程实例,为低成本实现通讯提供了一种解决方法。     

基于无线以太网的多线程数据采集系统设计

针对工业控制中现场总线存在电磁干扰大和串口数据传输不稳定、工程布线繁琐等问题,设计了一种以无线以太网为通讯方式的数据采集处理系统,介绍了数据采集系统的关键技术以及通讯软件的实现。实验证明该方案有效地解决了现场总线干扰问题,数据传输可靠性高,实时性好。     

基于VB串口通信的发动机水温测控系统开发

应用Honeywell专用的通讯协议开发DC1040数字控制器的通讯程序,通过计算机远程控制发动机试验水温。阐述了如何在VB6.0中使用Honeywell专用的通讯协议开发通讯程序从DC1040中读写数据,如何对计算机的串口进行正确配置。所用的通讯协议是DC1000系列数字控制器所通用的协议,所述方法对于使用VB6.0开发DC1000系列数字控制器通讯程序具备一定的参考作用。     

西门子S7-200串口通讯研究与应用实例

文章介绍了基于西门子S7-200可编程逻辑控制器的三种串口通讯方式,并采用自由口通讯模式阐述了一种PLC与计算机、PLC与条形码扫码设备进行数据交互的通讯系统设计。控制系统以西门子S7-200为核心,实现了不同标准接口设备稳定、灵活的串口通讯,并应用在实际工程项目中,运行稳定。     

基于M-Bus总线的热力站监测系统

M-BUS(‘Meter-Bus’)通讯总线是一种欧洲标；仁的仪表总线通讯格式．是为了远程读取热表而制定的一种新的欧洲标准。本文概述了基于M-Bus总线的热力站监测系统，并介绍了Mbus仪表总线协议以及应用串口读取m-bus总线内容的方法。给出了M-bus与RS232总线之间电平转换电路及其分析。     

利用串口通讯的分布式控制系统

本文介绍了由多台可编程控制器和亚当模块作为智能节点,通过串口通讯的分布式控制系统。     

一般问题

GJ20076005EPEC控制器在挖掘机总线通讯中的应用[刊,中]/杨翔…//工程机械.—2007,38(8).—1～3介绍了基于CAN总线的挖掘机总线通讯系统的基本构成,该系统主要由无线遥控器、控制器、传感器及显示屏构成其硬件平台,采用CAN总线作为系统中各单元之间交换信息的通道;分析了CANOpe     

基于ARM的抽油机变频器功能扩展和通讯控制器设计

为了解决抽油机变频器测控功能单一,通信串口不足的问题,设计一种基于ARM处理器的抽油机变频器功能扩展和通讯控制器,并给出了控制器软硬件的详细设计。该控制器能够协调监控中心与变频器、ZigBee等设备间的通讯,使用串口的DMA方式进行数据收发。通过ZigBee模块进行示功图数据的采集上传,采用单个接近开关和计算下冲程时间实现抽油机上、下冲程运行频率的实时切换。现场测试结果表明:该控制器通信稳定可靠,功能扩展方便,能够有效减少油田无线监控系统的建设成本。     

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.