基于高速数据采集的发动机参数远程测试系统

将虚拟仪器技术与USB接口技术相结合,实现高速采集的网络化测试系统.USB总线可以实现对数据实时高速的采集,把采集数据传送到主机后再通过LabVIEW的网络通信功能进行数据的远程传输.介绍了USB接口模块硬件和软件的设计方法,阐述了LabVIEW开发平台上网络化传输的实现方法,结合发动机测试,实现发动机参数远程虚拟测试系统.     

基于MODBUS无线总线测控系统

本文提出了将工业现场总线ModBus通讯标准引入到nRF无线通讯技术中,组成ModBus无线总线测控系统.采用nRF905芯片作为无线收发模块的核心,主机和分机的信息交换以射频无线总线的方式实现,数据的无线传输遵循ModSus(RTU)通讯协议,采用半双工的工作方式,频率工作在ISM频段.按照ModBus协议的RTU模式,设计RTU消息帧的结构和格式,通过无线总线实现了主机与分机之间的信息传输和控制各个分机的工作.     

基于CH372-USB总线芯片的FPGA控制器

USB逐渐成为现场调试和实时监测设备的标准接口,在比较了几种实现USB接口的方式后,采用FPGA与带USB底层协议的总线芯片来实现USB接口通信。采用FPGA作为主控芯片,设计了基于CH372-USB总线芯片的控制器,论述了控制器工作的原理和核心状态机的设计过程,解决了FPGA控制CH372时,CH372对时序和命令输入的要求。最后,搭建实验硬件平台,验证了该方案的可行性和有效性。     

基于USB接口的高精度电荷校准仪

采用虚拟仪器技术、直接数字合成技术和计算机技术设计了电荷校准仪,其工作状态由计算机USB接口控制,能输出多种波形的电压和电荷信号,电路中采用双DAC结构实现了幅值的精确控制.计量检验结果表明设计的电荷校准仪精度高、性能稳定,能够满足高精度的压电测试系统和电荷放大器的校准需要.     

基于USB2.0的生物信号采集系统设计

介绍了基于USB2.0的生物信号采集系统设计原理与实现,提出了使用FPGA控制A/D转换器完成高速、高精度数据的采集和存储,同时给出了基于FX2实现高速数据传输的USB总线接口方案.按照该方案设计的生物信号采集系统可以实现不间断、大容量数据采集和传输.     

典型工业网络系统实验平台的设计

基于工业以太网技术及现场总线技术,设计并建立了一个典型的工业网络系统实验平台,阐述了系统总体设计思想、工程架构,以及具体的软硬件实现方案.详细描述了基于OPC技术的工业以太网与现场总线PROFIBUS通信连接设计、现场总线PROFIBUS与AS-i网络互联设计,阐述了该系统平台的科研及实验功能,其具体工程实现技术也可以很容易地应用于实际的现场总线控制系统设计实践中.     

线阵CCD的高速信号采集与USB数据传输系统设计

介绍了一种用于线阵CCD高速位移传感器的信号采集与USB传输系统.系统以DSP为控制核心,采用高速AD转换器件AD9238和USB2.0接口控制芯片CY7C68013实现信号采集与高速数据传输的功能,给出了硬件电路和相关程序的设计方法.实验表明:在DSP的控制下,系统实现了CCD传感器信号的高速采集和实时传输.     

基于USB总线的LCOS数码彩扩仪驱动设计

介绍了一种利用USB传输视频数据的LCOS数码彩扩仪驱动设计方案。采用专用USB芯片实现图像数据传输,CPLD及SRAM实现视频数据的缓存,并由CPLD设计产生XGA信号驱动后端的LCOS控制芯片,最终实现了数码彩扩驱动系统的稳定输出,为实现LCOS数码彩扩系统提出了一种新思路,具有相当的实用价值。     

基于CPLD的膜片钳数据采集系统--UDA-Ⅰ数据采集器

针对膜片钳实验系统自动化发展的需要,采用基于CPLD芯片的数字逻辑控制单元和USB1.1数据传输总线,研究并实现了一种新的数据采集系统--UDA-Ⅰ(USB Data Acquisition,Ⅰ型)数据采集器.实验证明,本数据采集器的数据传输速率达到100K Bytes/s,信号噪声在土10 mV范围内,能灵敏、准确地实现数据传输,符合膜片钳实验高速数据传输的要求.     

基于USB接口的音频信号采集系统设计

对USB总线技术进行了介绍。设计基于USB2．0接口技术的数据采集卡。介绍了USB的硬件设计、固件设计和驱动程序设计。给出具体的硬件设计方案;进行固件设计与驱动程序设计,介绍CY7C68013的GPIF接口的设计。利用USB与DSP技术实现音频信号的数据采集、处理与传输。     

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...     

On the Relation of Load to Average Gap in the Contact Between Surfaces with Longitudinal Roughness

A computer simulation model for the contact between longitudinally-oriented rough surfaces has been formulated. This model closely duplicates the actual surf ace contact deformation behavior by taking into account the elastic interactions between the asperities. There were no assumptions made about the shapes, or any deformation behavior of the asperities, except for their obeying the laws of elasticity. The plastic deformations on the high asperity peaks were taken into account by setting a ceiling on their contact pressures at the material hardness value. The simulations used real surface profiles which were digitized from unworn circumferentially ground steel surfaces. Each pair of these profiles was mathematically combined to form an equivalent rough profile pressing against an infinitely rigid flat and having the appropriately adjusted elastic modulus. A total of 28 different pairs of profiles were used in the simulations. Each contacting pair was subjected to 30 different load levels and the local contact pressures and deformations were calculated. The contact simulations yielded some important mathematical relationships between parameters, such as the real area of contact, average gap, and average asperity load through statistical curve fitting. Two analytical functions were generated to relate the average load to average gap and the real area of contact to load.     

三绕组变压器的双绕组等效建模及在Matpower中的应用

针对实际电网存在着大量的三绕组变压器,但国际上一些著名商业软件,如BPA仿真软件、Matpower这一权威潮流计算开源软件,均只提供双绕组变压器模型,限制了其在具有三绕组变压器的电力系统中的应用的问题,潮流计算是自主开发的电力系统各种应用软件的核心模块,因此依托国际权威开源程序进行二次开发,是一种较好的选择。对Matpower要求的数据格式进行了归纳,对变压器的一般的等值电路及带理想变压器的等值电路和带标幺值的等值电路进行了分析研究,提出了三绕组变压器转换为双绕组等效模型的建模方法,使得原先只适应双绕组变压器的潮流计算软件可以适用于三绕组变压器电网的潮流计算;最后以Matpower软件为例进行了案例计算,并用PSASP仿真软件进行对比验证。研究结果证明,所提出的建模方法是有效的。     

Quantum Cooperative Robotics and Autonomy

The intersection of Quantum Technologies and Robotics Autonomy is explored in the present paper.The two areas are brought together in establishing an interdisci...     

电站锅炉模糊风险评价方法研究与应用

针对电站锅炉风险等级评价问题,将模糊综合评价技术应用到电站锅炉风险等级评价中。开展了电站锅炉失效影响因素及模糊评价因素的重要程度分析,建立了一套科学合理适于在线评价的电站锅炉风险评价体系,提出了模糊综合评价技术与改进的模糊层次分析法相结合的模糊风险评价方法,利用改进的模糊层次分析法计算了指标体系中各层指标权重。对某一台电站锅炉的实际运行工况影响子因素进行了模糊风险评价,采用模糊合成算子进行模糊综合运算得到电了站锅炉运行工况影响子因素的评价向量。研究结果表明:电站锅炉的运行工况影响子因素的风险评价等级为第6级,失效可能性等级为小,该电站锅炉运行工况良好。     

考虑进油孔有限长滑动轴承油膜力的近似解析解

针对具有进油孔的有限长滑动轴承油膜力求解问题,采用变分原理和分离变量法,求得了有限长滑动轴承油膜压力分布的近似解析表达式。将油膜压力分布的近似解析表达式在油膜存在区域上进行积分,即得到了油膜力。将提出的计算有限长滑动轴承油膜力方法与无限长轴承模型、有限元方法的计算结果进行了比较,发现了提出的方法与有限元方法的计算结果很接近。最后,研究了进油孔位置和进油压力对油膜存在区域、油膜力等的影响,研究结果表明进油孔位置和进油压力对油膜存在区域和油膜力有较大的影响。     

Fifth International Summer School on Screw-Theory Based Methods in Robotics

正3-11 September,2014University of Bologna,Bologna,Italy www.summerscrews.org summerscrews2014.ing.unibo.it SUMMER 20SCREWS 14In 2014,our screw-theory school comes to the world's oldest university.In early September,Summer Screws'14 will gather six experts in the application of screw theory in robotics and up to 40 participants at the University of Bologna,Bologna,Italy.The school will teach attendees how to apply existing methods and empower them to develop new ones in their own research.The basic theoretical notions will be introduced in a rigorous manner,emphasizing examples,applications,and exercises.Scholarships are available.     

交通荷载作用下桥梁结构参数识别方法

应用动力节点加载法,将作用在桥梁上的交通荷载转化为等效节点荷载,再用两步构造法识别结构物理参数.第1步,用Newmark-β方法变换结构运动方程,并用结构的加速度响应求得变换空间内的位移、速度和加速度响应;第2步,基于最小二乘原理,构造出变换空间内求解结构参数的递推式,进行结构物理参数识别.数值模拟结果表明,在交通荷载作用下,该方法能够快速、准确地进行桥梁结构参数识别.     

INDUSTRIAL ENGINEERING AND VISUALISATION-A PRODUCT DEVELOPMENT PERSPECTIVE

Taking the actual project of teaching and researching process for example, the relationship between the industrial engineering and product development is discussed. And use the novel visualization technology to support the industrial engineering and product development. How to use the new computer modeling and simulating technologies to support the product development and industrial engineering, is introduced especially. The support includes both domestic products and industrial systems. The visualization and computer technologies take a very important role in some system or multi-direction modeling, those technologies mentioned above can help the industrial engineers study the effect of design on the whole life circle, including the producing steps. So the engineers can avoid making the wrong decision which may cause bad effects on the whole industrial engineering.     

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.