基于FPGA的CAN总线通信节点设计

以FPGA代替传统的单片机和外围扩展芯片,给出了CAN总线通信节点的详细设计方案.其中以SJA1000为CAN总线控制器、FPGA为主控制器,设计实现通信节点的硬件接口电路.基于对CAN总线控制器的功能分析,并应用Verilog语言进行软件设计,从而实现CAN节点之间的通信功能.     

基于现场总线的监控网络节点的设计与实现

采用现场总线技术构建分布式监控通信网络系统,设计了基于AT89C52单片机的CAN总线控制器和RS-485通信节点硬件电路,介绍了CAN报文协议和MASTER-K120S系列PLC专用通信协议,并给出了通信软件的具体实现,连接计算机完成了数据的发送与接收。     

基于1553B与CAN总线的电机控制网络设计

基于DSP和CPLD设计了CAN-1553B网关,选择了1553B总线作为电机控制系统的主总线,其主要用于操作系统与子控制系统之间的通信。为了更好地完成各节点之间的通信,采用CAN总线作为子系统总线,构建基于CAN总线的由一个主控制器节点和一个采集执行节点组成的电机控制网络单元,实现两个节点之间的CAN总线通信以及电机的双模位置控制,并分析了控制性能。     

基于CAN总线的燃料电池客车通信网络设计

为了解决燃料电池电动客车各部件之间的通讯,基于CAN总线设计了整车通讯网络的拓扑结构,提出了其硬件要求.制定了CAN总线通信速率及通讯机制,介绍了CAN报文结构及协议.最后基于LPC2194微控制器和TJA1050高速CAN总线驱动器开发了各通信节点.实际应用表明,该系统稳定可靠.     

基于C8051F040的CAN总线技术的多节点通信网络设计

随着现在测控领域内要求得到的数据越来越多,总线上的各种传感器越来越多,对总线和各节点之间的通信的要求也越来越高,要求现场总线能对多节点的传感器进行实时的、灵活的、可靠的通信.为了满足这个要求,文中提出了一种基于C8051F040的CAN总线技术的多点通信网络.利用C8051F040内部的CAN控制器作为协议控制器,利用TJA1040作为物理层驱动器,用双绞线作为通信介质实现多点通信,同时通过USB-CAN转换模块和上位机软件实现PC机对数据的读取.文中详细介绍了多传感器节点通信网络的硬件电路和相关软件的具体实现方式.     

基于冗余CAN总线的船用阀门嵌入式控制系统

分析普通船用阀门控制的特点,将嵌入式微处理器技术应用于船用阀门,与工控计算机一同构成基于冗余CAN总线的船用阀门控制系统。控制系统由上位机与基于嵌入式微处理器的船用阀门控制器组成的多个节点组成。阀门控制器具有阀门开度信号的采集、电机电流采集等功能。节点通过冗余CAN总线技术实现与上位机的通信,便于实现船用阀门系统的闭环控制。文章详细介绍了控制系统的硬件和软件设计。     

纯电动汽车整车控制器的硬件在环技术建模研究

随着新能源汽车的快速发展,硬件在环测试平台在纯电动汽车整车控制器开发中占据重要地位。本文通过对纯电动汽车整车控制器的硬件在环测试提出理论指导依据,以某车型纯电动汽车整车控制器开发为例,利用硬件在环测试平台按照功能划分进行模型搭建以及在搭建整车模型过程中每一个对应零部件需注意的事项进行研究总结,为硬件在环技术应用于纯电动汽车整车控制器的开发提供参考,有效降低产品开发成本和周期,提高整车开发效率。     

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.     

电动汽车两档机械自动变速器控制器设计

针对目前电动汽车的选换挡品质欠佳和经济性低的问题,提出了新型电控式机械两档自动变速器设计。该变速器基于电动汽车电控式机械自动变速器控制器的结构以及工作原理,采用直流有刷电机作为电控式AMT控制器的执行选换档电机,选用了Freescale公司的MPC5634单片机设计了变速器控制器硬件电路,并通过分析电控式AMT的基本控制方式,设计了控制器的主程序以及各个子模块程序,增加了CAN通信模块和串口通信模块来实现电控式AMT控制器与整车系统的数据传输,最后对控制器进行了台架换档试验。实验结果表明:所设计的控制器能很好地实现选换档操作功能,且性能稳定。     

CAN总线工业测控网络系统的设计与实现

本文采用控制器局部网（CAN）和分散型计算机控制技术,成功地研制了CAN总线工业测控网络系统。该系统由多个主节点和多个从节点组成,且很好地实现了CAN总线工业控制网络的数据通信和现场测控功能。主节点监督和管理所有从节点,从节点测量和控制生产过程参数。     

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.     

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.