基于LabWindows/CVI的导弹舵机测控系统设计

舵机是导弹控制系统的重要执行机构,为实现对电动及气动多种型号导弹舵机性能的测试,设计开发了一种基于LabWindows/CVI虚拟仪器的测控系统。介绍了该测控系统硬件组成和软件结构流程,软件设计过程中充分利用多线程、数据库等技术,准确快速完成舵机自动化性能测试。应用结果表明:该舵机测控系统工作稳定,测试精度和自动化程度高,满足舵机试验测试精度和技术指标要求,为舵机的性能研究和维修维护提供了良好的测试环境。     

一种测量重核素的小型高压型加速器控制系统的研制

为满足中国原子能科学研究院最新研制的400 kV小型重核素加速器质谱（AMS）装置的自动控制的需求,设计并实现了针对该装置的自动控制系统。从硬件和软件两个方面描述了系统结构。虚拟仪器LabWindows/CVI9.0、PLC、数据库、组态软件等的相结合,既组建了友好的人机交互界面,又提高了系统的可靠性。自主设计的具有较高自动化水平的气体剥离器控制,实现了同步监测、控制气体流量和真空度。自动换靶控制的零位指示和靶号显示相配合,更精确地实现换靶功能,提高了装置自动化程度。经长时间测试,该测控系统满足了加速器质谱系统的自动控制及就地操作需求。     

船载USB/UCB自动化测试系统的设计与实现

针对船载USB/UCB测控系统技术指标测试、系统自检工作复杂的特点,分析USB/UCB测控系统的关键信号节点,借助LabWindows/CVI软件及GPIB总线的支持,构建船载USB/UCB自动化测试系统。该系统可在系统监控台的统一组织下,结合系统内其它设备,采取无线/有线、射频/中频等方式,灵活组建测试平台,完成相应指标的自动化测试。通过对上行链路三阶交调测试结果分析,表明该自动化测试系统操作简便快捷、测试结果准确可靠。     

LabWindows与西门子PLC的3种数据通信方式研究

针对LabWindows/CVI与S7-300 PLC通过MPI、IE以及OPC 3种通信方式建立连接及数据通信的应用场合和具体实现方法进行了研究,具有很好的工程应用价值,并依次完成了3种通信方式下LabWindows/CVI对西门子CPU 314C-2DP跑马灯程序的实时监控实验。实验证明3种数据通信方式稳定可靠,可以根据不同实际测控系统需求选择使用。     

某型瞄准线稳定测试系统RS232串行通信的研究

某型瞄准线稳定测试系统是用于测试和检验班组武器系统、轻型低空反导转管机枪等武器系统中的光电跟踪子系统瞄准线独立性能的专用设备;介绍利用LabWindows/CVI实现上位机与下位机之间的通信,设计了瞄准线稳定测试系统,分析了下位机需要实时检测的物理量信息;为了提高系统的可视性和实现对下位机的控制,通过RS232串行通信技术向上位机传输数据;对上位机利用LabWindows/CVI的控件实现数据采集,数据显示和存储进行了研究;实验结果表明,基于LabWindows/CVI的RS232串行通信的上位机数据采集与显示系统具有可视性强、操作简单等特性。     

一种高准确度光纤光栅波长解调系统

为了消除F-P滤波器的温度特性对光纤光栅波长解调系统准确度的影响,提出了一种采用F-P标准具作为波长参考计算波长的方法,设计了一种高准确度波长解调系统,并采用虚拟仪器开发平台LabWindows/CVI实现了光谱数据的滤波、寻峰及波长计算算法.测试结果表明,该系统的重复性误差小于1.56 pm,稳定性误差小于1.13 pm.     

LabWindows/CVI在导引头地面测控设备中的应用

针对某型导引头挂飞试验实现导引头控制及实时性高的需求,设计了一种基于LabWindows/CVI软件开发平台的挂飞控制箱系统。该挂飞控制箱通过RS422串口与导引头相连,能够实现导引头控制、状态显示、GPS信息接收处理、试验数据存储等功能。挂飞控制箱采用VXI总线和LabWindows/CVI软件平台进行设计,硬件集成度较高,软件运用LabWindows/CVI开发平台自带的多线程技术,将串口通讯等周期性任务与数据处理、存储、显示等任务从时间上分开,提高了CPU工作效率,满足系统实时性要求。试验结果表明,该挂飞控制箱系统工作稳定,与导引头通讯可靠,实时性较高,试验数据完整且满足总体要求。     

基于虚拟仪器的电磁干扰近场测试系统设计

针对传统电磁干扰测试存在的环境要求苛刻、操作复杂及费用昂贵等问题,设计了一套基于虚拟仪器的电磁干扰近场测试系统。以近场探头和频谱仪组成系统硬件主体构架;运用LabWindows/CVI平台的交互式界面设计实现测试项目统一管理,通过VISA技术和NI-DAQmx完成频谱仪的控制和数据采集模块的设计。系统可满足非标准测试的需求,提高测试效率,并且开发周期短,兼容性强,具有一定的实用性与推广价值。     

基于CVI和VC++混合编程的雷达天线测试平台的软件设计

为了提高雷达天线系统外场的测试水平,研制了一种便携式雷达天线系统测试与控制平台;文章介绍了平台的组成结构,并详细地介绍了平台的软件设计;平台的软件设计采用LabWindows/CVI和VC++混合编程的思想,利用LabWindows/CVI开发了上层应用程序, 实现了良好的人机交互界面,采用VC++6.0开发了底层驱动程序,底层驱动程序以动态链接库形式封装,保证了硬件测控的实时性;实际应用表明该软件能满足雷达天线系统测试的需求,并能保证整个测试平台的实时性和可靠性,简化了测试过程。     

基于虚拟仪器的舵机综合测试系统设计

为了在实验室条件下模拟舵机系统实际飞行时所受的气动载荷,实现舵机部件和整机的动静态测试,设计了基于虚拟仪器的舵机综合测试系统。针对舵机测试系统自动化化和综合化需求,基于PXI架构和LabWindows/CVI平台,完成了测试系统的硬件设计和软件设计,采用异步定时器实现了实时数据采集,采用tdms数据流实现了大容量高速数据的记录,运用多线程实现了良好的人机交互与流畅的曲线显示,采用ActiveX技术调用Excel实现了测试报表的自动生成。使用和测试结果表明,该测试系统显著提高了舵机测试的效率和精确度以及自动化水平,使用方便,性能稳定,为舵机性能测试和设计优化提供了可靠保障。     

Design of multiplexed fiber optic chemical sensing system using clad-removable optical fibers

To prevent possible threats to public safety and economic loss from chemical leakage accidents, novel chemical sensing techniques for regular monitoring and leakage detection have been developed for various fields. We propose a fiber optic liquid chemical sensor (FOCS) system using specialty optical fibers and an optical time domain reflectometer (OTDR), and is based on the leaky wave mode sensing principle. OTDR enables simple multiplexing where individual sensor nodes along the fiber length could be interrogated by a common OTDR. The sensor node in the optical fiber is prepared by removing the desired length of a protective layer using mechanical stripping and chemical etching techniques. A novel laser stripping technique with superior capability to fabricate quasi-distributed dense sensor nodes is devised as well. The FOCS system is further analyzed to characterize the sensor response behavior in relation to the sensor node length and possible environmental and chemical temperature effect. Under the condition satisfying the leaky wave mode principle and within the minimum acceptable refractive index (RI) range by the system, this FOCS system could monitor numerous liquid chemicals with variable refractive indices and has been tested with positive results. In addition, the system shows the possibility for multi-point detection and is further expanded into a hybrid technique capable of estimating the refractive index range of the detected chemical.     

基于GTM900-B的化学工业区气体检测终端设计与实现

化学工业区的中往往密布气体输送管道,这些管道专门布置在公共管廊中进行管理和监控,管道内易燃、易爆、有毒等气体泄漏的远程检测尤为重要。传统的检测设备具有一定的局限性,需要设计能联网的、小型化的、低成本的数据采集终端。因此设计出一种基于GTM900-B化学工业区气体检测终端,用于组建基于GPRS网络的化学工业区气体检测系统。该终端可向网络控制和管理中心发送可燃气体、氯气和氨气等气体泄漏数据,并且具有报警功能。软硬件测试和实际应用结果表明所设计终端的可行性和有效性。     

基于无线传感器网络及GPRS的水质监测系统设计

提出了一种基于ZigBee无线传感器网络和GPRS技术的多参数远程实时水质监测系统。无线传感器网络以CC2430通信模块为核心。传感器节点采集到的数据经路由节点汇总至协调器节点,通过GPRS模块及时远传至监控中心。设计信号调理电路,将传感器电极输出的微弱电信号进行放大、滤波。采用时间同步机制实现网络节点的同步唤醒,大幅提高网络的稳定性。对系统进行了多天连续测试。通信距离为100米时,网络的平均丢包率低于1%。pH值、溶氧度的平均相对偏差低于1%。测试结果表明,系统具有灵活、实时性好、准确性高、稳定可靠等优点,具有很强的实用价值。     

Experimental studies of using wireless energy transmission for powering embedded sensor nodes

A major challenge impeding the deployment of wireless sensor networks for structural health monitoring (SHM) is developing a means to supply power to the sensor nodes in an efficient manner. In this paper, we explore possible solutions to this challenge by using a mobile-host based wireless energy transmission system to provide both power and data interrogation commands to sensor nodes. The mobile host features the capability of wirelessly transmitting energy to sensor nodes on an as-needed basis. In addition, it serves as a central data repository and processing center for the data collected from the sensing network. The wirelessly transmitted microwave energy is captured by a receiving antenna, transformed into DC power by a rectifying circuit, and stored in a storage medium to provide the required energy to the sensor node. The application of wireless energy transmission is targeted toward SHM sensor nodes that have been recently developed by the authors, which can be used to collect peak mechanical displacements or piezoelectric impedance measurements. This paper will describe considerations needed to design such energy transmission systems, experimental procedure and results, method of increasing the efficiency, energy conditioning circuits and storage medium, and target applications. Experimental results from a field test on the Alamosa Canyon Bridge in southern New Mexico will also be presented.     

回归的能源有效网络大数据流汇聚算法研究

为了降低传感器网络数据流汇聚时的能源消耗,提出了一种基于回归的能源有效数据流汇聚算法。首先,将传感器节点分为活跃节点和能源有效节点。然后,以活跃节点为中心点将所有节点进行聚类,并应用回归方法通过活跃节点的数据流对能源有效节点的数据进行预测。接下来,通过节点预测值的累积误差不断修正活跃节点集。最后,应用活跃节点的数据流信息对能源有效节点的数据进行预测。实验表明,本文提出的算法与其它相关算法相比具有更好的预测准确性。     

基于LabVIEW的多点串联光纤传感系统设计

设计了一种远程多点光纤传感系统用于大范围对象测量,其结构为一个本地控制节点通过双向光纤链路串联所有远端传感节点。在本地控制节点共享光源、光电检测器等光电器件,并结合虚拟仪器实现数据处理电路;而远端传感节点仅包含敏感元件、无源光器件构成的光路,并能直接实现时分复用。以3节点系统的甲烷气体检测为例进行实验和计算,结果证明该方案能够有效工作,通过循环检测可使首个传感节点的相对误差降至0．2％以下。     

Development of capacitance-based and impedance-based wireless sensors and sensor nodes for structural health monitoring applications

A field demonstration of a new and hybrid wireless sensing network paradigm for structural health monitoring (SHM) is presented. In this paradigm, both power and data interrogation commands are conveyed via a mobile agent that is sent to each sensor node to perform individual interrogations, which can alleviate several limitations of traditional sensing networks. This paper will discuss such prototype systems, which will be used to interrogate capacitive-based and impedance-based sensors for SHM applications. The capacitive-based wireless sensor node is specifically built to collect peak displacement measurements. In addition, a wireless sensor node for collecting electromechanical impedance data has also been developed. Both sensor nodes are specifically designed to accept various power sources and to be wirelessly triggered on an as-needed basis so that they can be used for the hybrid sensing network approach. The capabilities of these miniaturized and portable devices are demonstrated in the laboratory and the field, which was performed at the Alamosa Canyon Bridge in southern New Mexico.     

推荐重要节点部署防御策略的优化模型

当前网络安全防御策略集中部署于高连接度节点主要有2个方面的不足: 一是高连接度节点在很多场合中并不是网络通信的骨干节点; 二是该类节点对信息的转发和传播并非总是最有效的.针对以上传统部署策略的不足, 改进了恶意病毒程序传播的离散扩散模型并采用中间路径跳数来衡量网络节点的重要程度, 提出了基于介数中心控制力和接近中心控制力模型的重要节点优先推荐部署技术.实验结果显示具有高介数中心控制力和低接近中心控制力的节点相对于传统的高连接度节点无论在无标度网络还是小世界网络均能够对恶意病毒程序的疫情扩散和早期传播速度起到更加有效的抑制作用, 同时验证了网络分簇聚类行为产生的簇团特性也将对恶意程序的传播起到一定的负面影响.     

Attractive target wave patterns in complex networks consisting of excitable nodes

This review describes the investigations of oscillatory complex networks consisting of excitable nodes,focusing on the target wave patterns or say the target wave attractors.A method of dominant phase advanced driving(DPAD) is introduced to reveal the dynamic structures in the networks supporting oscillations,such as the oscillation sources and the main excitation propagation paths from the sources to the whole networks.The target center nodes and their drivers are regarded as the key nodes which can completely determine the corresponding target wave patterns.Therefore,the center(say node A) and its driver(say node B) of a target wave can be used as a label,(A,B),of the given target pattern.The label can give a clue to conveniently retrieve,suppress,and control the target waves.Statistical investigations,both theoretically from the label analysis and numerically from direct simulations of network dynamics,show that there exist huge numbers of target wave attractors in excitable complex networks if the system size is large,and all these attractors can be labeled and easily controlled based on the information given by the labels.The possible applications of the physical ideas and the mathematical methods about multiplicity and labelability of attractors to memory problems of neural networks are briefly discussed.     

The selection of layer thicknesses to control acoustic radiation force profiles in layered resonators

Ultrasonic standing waves can be used to generate radiation forces on particles within a fluid. A number of authors have derived detailed representations of these forces but these are most commonly applied using an approximation to the energy distribution based upon an idealized standing wave within a mode based upon rigid boundaries. An electro-acoustic model of the acoustic energy distribution within a standing wave with arbitrary thickness boundaries has been expanded to model the radiation force on an example particle within the acoustic field. This is used to examine the force profile on a particle at resonances other than those predicted with rigid boundaries, and with pressure nodes at different positions. A simple analytical method for predicting modal conditions for combinations of frequencies and layer thickness characteristics is presented, which predicts that resonances can exist that will produce a pressure node at arbitrary positions in the fluid layer of such a system. This can be used to design resonators that will drive particles to positions other than the center of the fluid layer, including the fluid/solid boundary of the layer, with significant potential applications in sensing systems. Further, the model also predicts conditions for multiple subwavelength resonances within the fluid layer of a single resonator, each resonance having different nodal planes for particle concentration.