基于工业以太网EtherCAT的DCS控制系统设计

EtherCAT是一种新型的工业以太网现场总线技术,在工厂自动化和流程自动化领域得到了广泛应用.文章介绍EtherCAT现场总线的技术特点,设计了一套基于EtherCAT的DCS实例系统.该系统中主控制器单元和现场输入输出设备之间使用EtherCAT实现高速、大容量的数据通信,并使用标准以太网与中央控制器进行数据交换.     

基于以太网的废旧电缆自动剥线装置设计

针对工程废旧电缆铜芯回收效率低的问题,设计基于以太网的废旧电缆自动剥线装置。具体设计了基于profinet总线式网络控制系统,执行层采用西门子1200系列PLC作为主控制器,采用通信方式实现对各执行电机的控制、手持式触摸屏实现现场设备的操控、工控机实现数据采集与远程监控,各部分以通信方式实现数据共享和执行部件的协同控制。经实际应用表明,基于以太网总线控制式电缆剥线装置功能强大、现场走线少、可靠性高,可有效提高废旧电缆的剥线、回收效率。     

基于EPA工业以太网的现场控制器研制

介绍EPA工业以太网和网络控制系统的基本结构，提出了基于EPA工业以太网和Compact PCI总线的先进现场控制器的解决方案，分析并解决了控制器通讯实时性调度协议、确定性通讯、现场总线集成等几项关键技术，使网络控制系统在开放性、可靠性、运算执行能力等方面具有良好的性能。     

EtherCAT协议芯片与单片机通信系统的研究

EtherCAT是基于标准的以太网技术,具有灵活的网络拓扑结构,系统配置简单,具有高速、高有效数据率等特点,其有效数据率可达90%以上.PIC系列单片机和EtherCAT协议芯片通过SPI串行通信方式进行连接,实现基于EtherCAT协议通信系统的基本通信功能,解决了传统以太网的介质访问控制方式不能满足工业现场实时性要求的问题.系统测试实验表明,系统通信准确,运行稳定,而且通过分析系统通信过程中的报文可知,系统的通信完全符合EthercAT 协议的要求.     

基于EtherCAT总线的簇绒地毯机提花控制系统

为了提高簇绒地毯机提花控制的实时性和通讯速度,将实时工业以太网技术EtherCAT应用于提花控制系统。该系统选择倍福PLC作为主控制器,采用步进电机带动提花轮的提花方式,通过实时改变各步进电机的转速来控制提花轮的喂纱量。提花系统中每根纱线由一个独立的步进电机控制,提花的分辨率精确到了1针,可以织出满幅循环的地毯花型。硬件上设计了基于LAN9252的EtherCAT通讯接口模块和基于STM32F103RCT6的步进电机提花控制器,并在STM32中移植了从站协议栈代码,实现了通过EtherCAT总线对多步进电机的同步群控。     

基于EtherCAT的五自由度机械臂控制系统研制

对自行设计的五自由度机械臂进行了运动学分析。为了实现对机械臂控制的实时性和可扩展性,研制了一种基于以太网控制自动化技术(EtherCAT)总线通信的机器人控制系统,采用ACS公司的SPiiPlus软件作为软主站,以ACS公司的两款基于EtherCAT的数字伺服驱动器UDMmc、UDMlc和Beckhoff公司的EK1100耦合器模块作为从站组成EtherCAT实时系统。对EtherCAT的主从站进行了一系列配置,并在五自由度机械臂平台上验证了轨迹规划的平稳性和系统的稳定性、实时性。     

基于蓝牙通信技术的嵌入式工业控制系统的开发

传统的工业控制系统中主要以PLC和DCS作为控制设备,但是PLC和DCS的控制成本高、实时性差的缺点使得它们难以满足飞速发展的现代工业对控制系统的需求。而嵌入式控制系统以其成本低、性能高、实时性好的优势在工业领域的应用不断扩大,设计了基于嵌入式的工业控制系统,包括模块化的数据采集系统、蓝牙通信系统和以ARM9为主控制器,在Linux操作系统下通过Qt4编程完成一款工控GUI.模块化的数据采集系统对采集的数据进行放大、线性化、滤波等处理后,再经过C8051单片机进行A/D转换后通过蓝牙通信技术传输给主控制器进行数据处理并将处理完成的数据通过总线返回给工业现场。试验证明,该控制系统对数据处理的精度高,速度快,实时性好,可以满足工业现场的应用需要。     

EtherCAT总线技术在新装备中的应用

通过对EtherCAT总线技术实时性强、可靠性高及传输速率快等技术特点的研究分析,根据新装备的特点和测试控制需求,论文阐述了将实时以太网引入新装备中的必要性和可行性。通过搭建EtherCAT总线实验仿真平台,以TwinCAT实时系统为研究工具,重点验证了EtherCAT总线技术满足新装备对实时性、可靠性、传输速率和热插拔的需求。     

基于Linux的EtherCAT主站的研究

实时工业以太网已经成为当今工业用现场总线的主流,本文研究了Linux下EtherCAT主站的结构,为开发基于软主站的开放式运动控制器提供了技术储备.进而为研制我国自己的工业实时以太网标准提供借鉴.     

基于ARM技术的以太网与CAN现场总线协议转换网关的设计与实现

介绍了一种以太网与CAN现场总线之间协议转换网关的设计与实现.该网关采用ARM微处理器AT91RM9200作为主处理器,通过MCP2510通信芯片与基于CAN总线协议的现场网络进行连接,可以实现CAN总线与基于TCP/IP协议的以太网络之间的双向通讯.     

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.     

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。     

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....     

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.     

Limits of topographic measurement by the scanning tunnelling and atomic force microscopes

Parameters describing the topographic character of a surface (height, surface wavelength, slope and curvature) can be derived from equivalent sinusoidal profiles. The response of a surface-measuring instrument may be modelled in terms of instrument parameters such as stylus radius, and scanning range and resolution. The performance of the instrument may then be mapped as a zone in amplitude-wavelength (AW) space to show the sinusoidal profiles it is capable of measuring. In a first-order analysis the STM and AFM are considered as equivalent to contact-stylus instruments with a notional stylus radius equal to the tip radius plus the gap. Comparisons between different instruments and types of instrument are readily made by mapping in AW space. The error arising from convolution of the sinusoidal profile with that of the finite tip may be quantified and plotted as contours in AW space.