基于SOPC的CAN总线系统设计与实现

提出了一种基于SOPC(片上可编程系统)的CAN总线系统,介绍了CAN总线控制器IP核的设计方法和系统结构,并在Altera的FPGA芯片上实现了集成微处理器核、存储器、CAN控制器IP核以及控制器软件的完整CAN总线系统,通过测试该CAN总线系统的具有良好的工作性能.     

基于LPC2292的Ethemet-CAN转换器的设计与实现

为了解决以太网和CAN总线之间的互联问题,将煤矿井下现场总线控制系统改造为以太网络分布式控制系统,研发了基于LPC2292微处理器和RTL8019AS以太网控制器的Ethernet-CAN转换器.LPC2292采用嵌入式TCP/IP协议栈通过RTL8019AS与以太网中的设备进行通信,利用LPC2292集成的CAN控制器与CAN总线上的终端进行通信.在通信过程中,LPC2292进行TCP/IP协议和CAN协议之间的转换.经验证,该转换器很好地完成了两种网络之间的协议转换和数据通信.     

CAN总线在结晶器振动监控系统中的应用研究

根据CAN总线的技术特点,提出了基于CAN总线的结晶器振动监控系统设计方案,介绍了CAN总线网络结构和MC9S12DG128的CAN控制器结构.在硬件电路设计中,对CAN总线实现原理及设计要点进行了详细介绍,软件部分给出了以控制器为核心的CAN总线节点模块的应用层软件.实验表明:该通信系统性能稳定、可靠、成本低,具有较高的实用价值.     

8051 IP 核与 CAN IP 核的接口技术

利用SOPC技术,将8051 IP核与CAN IP核有机融合,提出了一种创新型的控制器局域网（ CAN）节点设计方案。介绍了如何使用硬件描述语言（ HDL）实例化8051 IP 核和CAN IP核,描述了这两个软核的接口类型及它们之间的握手细节。编写测试程序,综合整个工程,并将生成的工程代码下载至FPGA运行。结果表明：使用SOPC技术设计的CAN节点通信良好,利用可重配置的IP核技术,可以实现更加复杂的功能,系统的设计也会更加灵活、稳定、可靠。     

基于LPC2292的Ethernet—CAN转换器的设计与实现

为了解决以太网和CAN总线之间的互联问题,将煤矿井下现场总线控制系统改造为以太网络分布式控制系统,研发了基于LPC2292微处理器和R．TL8019AS以太网控制器的Ethemet—CAN转换器。LPC2292采用嵌入式TCP／IP协议栈通过RTL8019AS与以太网中的设备进行通信,利用LPC2292集成的CAN控制器与CAN总线上的终端进行通信。在通信过程中,LPC2292进行TCP／IP协议和CAN协议之间的转换。经验证,该转换器很好地完成了两种网络之间的协议转换和数据通信。     

基于CAN总线的烧结配料监控系统

介绍了一种基于CAN总线的烧结配料监控系统的设计.利用CAN总线实现系统内部控制器组网,利用组态王软件实现上位机监控,系统一方面对整个生产线进行实时监测,另一方面对现场设备进行独立远程控制,实现了分布式控制和集中管理.另外,系统中各个控制器采用单片机实现,体积小、成本低.     

工业在线色谱仪温控器的DeviceNet智能通信节点的设计

针对目前国产工业在线气相色谱仪对较高实时性和可靠性的要求,研发了基于CAN总线DeviceNet协议的工业气相色谱仪温度控制器.系统以ATmega128单片机为核心处理器,CAN总线为底层通信网络,上层网络通信协议采用国标DeviceNet协议.温度控制信号通过CAN总线从上位机发送给温度控制器的DeviceNet智能节点.在设计中,建立了DeviceNet的基本模型,实现了基于8位高速单片机ATmega128的DeviceNet软硬件设计.     

基于FPGA的工程机械CAN总线技术研究

介绍了一种利用FPGA实现工程机械CAN总线的设计思路。在Altera的Cyclone系列的FPGA芯片上实现了NIOS、Flash、SDRAM和CAN控制器核的系统设计,并在NIOS IDE中完成了系统软件设计,通过USB—CAN工具测试该CAN核具有良好的性能,与EPEC2024控制器和ST104显示器等通信表现出了优异的可靠性和稳定性。     

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     

基于虚拟仪器技术的CAN总线转接器

设计了基于虚拟仪器技术的CAN总线转接器.以单片机和SJAI000 CAN总线控制器为核心构成下位机通信模块;以LabVIEW为开发平台,设计了上位机控制软件;上位机通过串口与下位机通信,实现上位机对CAN总线上的数据监测,还可以实现上位机向CAN总线各节点发送数据.实践表明此转接器具有一定的适用性,可以应用于某些CAN总线系统中.     

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.