虚拟制动试验台信号采集与监控系统

以信号分析理论为基础,采用虚拟仪器技术,辅以多参量数据采集模块化硬件,设计开发了基于VC 6.0虚拟仪器技术的制动试验台信号采集与监控系统,对制动试验台面临技术老化的状况进行了改进。本文较详细地介绍了该系统的硬软件结构、功能和设计思想及理论依据。经实验验证,其性能符合要求,完成了对试验台常用信号的采集以及对试验台的开关控制。     

A hybrid control architecture and coordination mechanism in virtual manufacturing enterprise

The concept of Virtual Enterprise (VE), a special organization of manufacturing units and enterprises, has attracted considerable attention in recent years. Unlike traditional enterprise, VE is most suitable in production environments that experience frequent changes in product mix. To complete a complex task composed of some sub-tasks, traditional control architecture is not versatile enough to coordinate and schedule multi-site and multi-type resources, especially in resolving resource conflicts during operations. Using hybrid control architecture, VE can execute the effective control on multi-site enterprises to support the rapid response to customer demands. Coordination mechanism running through the total life cycle of VE is applied to coordinating and scheduling the requests from different tasks and resources, which make VE flexible, adaptive and robust. In this paper, the hybrid control architecture based on multi-agent technology that supports the cooperation of enterprises is presented. Coordination mechanism and the corresponding optimal models are discussed. Finally a case study is used as an illustration to present the detailed coordination mechanism.     

协调加载控制及数据采集系统的自动校准设计

利用标准仪器的通信接口,在VEE Pro软件开发平台上设计出一套针对协调加载控制和数据采集系统的自动校准平台.该系统由仪器信息采集、伺服控制通道校准、数据采集通道校准、打印输出4个主模块组成,可实现实时显示、超差报警、自动处理数据及存档等功能.应用结果表明:自动校准平台高效、准确、可靠,在直升机研发试验中发挥出重要作用,具有广泛的应用前景.     

Status of the JET control and data acquisition system CODAS

This paper presents the current status of the JET Control and Data Acquisition System (CODAS). This system is the result of the effort of the whole CODAS team.     

Fastbus data acquisition for CDF

All CDF event data are collected in a multilevel FASTBUS network. At the lowest level of this network, MEP/MX and SSP scanners read and buffer data from RABBIT and FASTBUS front end systems. Operation of these front end scanners is coordinated by the Trigger Supervisor module which initiates parallel readout after receiving Level 1 and Level 2 triggers. Dataflow from scanners to consumer processes on host VAX computers is supervised by the Buffer Manager which directs an Event Builder to collect and format data from a set of scanner modules. This system is designed to allow partitioning into semi-independent sections for parallel development and calibration studies.     

Efficient data acquisition for engineers

A method of simple modular data acquisition is described. The approach is currently used by engineers for a wide variety of applications. It is particularly useful for engineers who have a limited knowledge of computer programming.     

室温磁制冷往复式系统控制采集系统开发

介绍室温磁制冷系统的流程。在往复式室温磁制冷系统实验台中用模块化方法分别开发针对电磁阀、步进电机和变频器的控制系统以及温度、流量和压力的采集系统,并集成开发采集控制的软件系统。     

随钻声波测井仪数据采集电路设计

针对随钻声波测井仪数据采集系统的快速、高精度、接口传输速度可编程控制的要求,设计了一种以"前端模拟调理模块+ADC+DSP"架构为核心的四通道数据采集电路。详细介绍了电路的硬件结构和软件设计流程,着重阐述了模数转换之前的信号调理模块和ADC与DSP之间的通信接口的实现。实验结果表明:该数据采集系统能够在随钻声波测井仪控制系统的控制下稳定可靠地完成声波测井数据的采集,满足工业生产作业的需要。     

Personal computer-basedcamac system for data acquisition

A single board auxiliarycamac crate controller for a Z80-A based personal computer ZX-spectrum to drive thecamac crate housing multipleadc, tdc, dac and 16 I/O ports has been developed. Thecamac crate controller used in this system is of A2 type which supports multiple auxiliary crate controllers. Acamac exerciser/training software for the use ofcamac commands in process control as well as data acquisition has been developed.     

Organizing a virtual manufacturing enterprise: an analytic network process based approach for enterprise flexibility

Virtual manufacturing is a dynamic enterprise structure that will enable future competitiveness in the fast changing business environment. This is made possible through quick IT based integration of flexible and core competent business entities capable of providing value-added product and services. Flexibility elements represent change capabilities of enterprise wide processes and resources in time and cost dimensions. Value chain considerations require synergy among the participating flexible resources. Also decision information synchronization delays need to be managed so that other entity flow processes in the enterprise remain well synchronized. This may require a capability of dynamic changes in flexible structures leading to effective virtual enterprises. There is a need to develop suitable enterprise architectures for virtual enterprises that offer an increasing focus on agility. Infrastructure support for integration of flexible capability to attain synergy among resources is necessary for enterprise agility. We conceptualize virtual manufacturing (VM) as an integrating infrastructure of flexible resources made possible through alliance of enterprises that are individually core competent in specific business function. Such a VM can attain the required cost, flexibility and responsiveness characteristics in its operations to provide solution to the demanding customer in a global dynamic market. Modelling frameworks depicting these composite flexibility states have complex and tacit interrelationship with plural business goals. Analytical network process (ANP) has been used to model the interrelationship of different decision domains with a view to prioritize enterprise wide flexibility dimensions. The ANP modelling framework takes into consideration the interdependency among sub-strategies. We demonstrate through sensitivity analysis that strategic shift is required to accommodate changes due to dynamic condition in the business environment.     

A modular acquisition system for coincidence data

A modular extendable acquisition system for coincidence data is developed, which uses commercially available high-stability high-precision ADCs. The basic functions in the system are incorporated each in a specific type of module, which offers maximum flexibility. The user can define the relevant types of coincidences by making the connections between the different modules. Many tools are provided that make it easy to set up and to monitor the system. Data latching, a fast clear, and the possibility of pileup rejection are implemented. Extension possibilities, included in the concept, are discussed. The maximum throughput of the system is such that the conversion-time of the ADCs and the maximum data-rate of a magnetic-tape unit are the limiting factors.     

A RISC architecture for high-speed data acquisition

A RISC architecture specifically designed for selective storage of high-speed digital words is presented. A specialized instruction set is created to allow programmable control of trigger conditions and storage memory. A RISC architecture is required to execute the instruction set and maintain a 10-MHz sample rate. The utility of the RISC system is illustrated by implementing both analog and digital data acquisitions. A prototype system was designed and fabricated for evaluation. Features of this design are presented     

High-accuracy data acquisition architectures for ultrasonic imaging

This paper proposes a novel architecture for a data acquisition system intended to support the next generation of ultrasonic imaging instruments operating at or above 100 MHz. Existing systems have relatively poor signal-to-noise ratios and are limited in terms of their maximum data sampling rate, both of which are improved by a combination of embedded averaging and embedded interleaved sampling. "On-the-fly" pipelined operation minimizes control overheads for signal averaging. A two-clock sampling timing system provides for effective sampling rates that are a factor of 20 or more above the basic sampling rate of the analog-to-digital converter (ADC). The system uses commercial field-programmable gate array devices operated at clock frequencies commensurable with the ADC clock. Implementation is via the Xilinx Xtreme digital signal processing development kit, available at low cost. Sample rates of up to 2160 MHz have been achieved in combination with up to 16384 coherent averages using the above-mentioned off-the-shelf hardware.     

高精度数据采集在压力测控系统中的应用

基于Window98平台，利用PC-7423A/D转换卡对压力测控系统中的压力信号进行采集，并通过几种定时方法的比较，选用多媒体定时器实现了对压力数据的定时获取。同时，采用数字滤波、自适应校正算法进一步提高了采集精度。最后，给出了用VC 开发的程序实例。     

LabVIEW的虚拟仪器数据接口设计与实现

LabVIEW是一种基于G语言的虚拟仪器开发环境 ,其数据接口设计是进行系统功能扩展的重要方法。本文在分析虚拟仪器软件LabVIEW特点的基础上 ,给出了虚拟仪器的数据接口途径 ,设计并实现了两种LabVIEW的数据接口 ,重点解决了虚拟仪器中的大数据量数据处理与模块共享问题。最后给出了设计实例。实践表明 ,此机制高效、易行 ,是增强LabVIEW数据共享及功能扩展的很好途径     

HP-NIM data acquisition system

A Hewlett Packard desktop computer has been connected through a Data Ready Flag with NIM ADCs to produce a data acquisition system which can be used for cosmic ray telescope detector applications. The system has been tested with a two detector telescope irradiated with beams of ²⁰Ne ions accelerated to 230 and 376 MeV.     

通过虚拟经营打造包装强势企业

面对经济全球化,国际理论界与企业实践界都普遍地认识到传统的企业经营管理模式已很难适应当前的竞争环境和未来企业组织发展的趋势,并积极探索、寻求新的发展模式.     

基于虚拟仪器的高准确度同步采集系统

针对工业生产、医疗以及科学研究过程中多路微弱信号检测的需求,采用FPGA并行控制实现16通道的同步采集,使用大动态范围的24位模数转换芯片和低噪声模拟调理电路获得较高的信噪比,USB高速接口的设计解决大量数据实时传输的问题,基于LabVIEW的上位机软件实现多通道数据的同步采集、传输、处理和存储。高精度硬件和虚拟仪器平台的结合,能够快速搭建检测系统,并且方便对仪器进行维护、扩展和升级。