分析虚拟仪器软件代替硬件仪器的应用

1、分析虚拟仪器软件代替硬件仪器的使用在仪器设计或测试系统中尽可能用软件代替硬件，即“软件就是仪器”，它是在通用计算机平台上，根据用户需求来定义和设计仪器的测试功能，其实质是充分利用计算机的最 新技术来实现和扩展传统仪器的功能，这种测试仪器的硬件功能软件化，给测试仪器带来了深刻的变化，因此虚拟仪器代表了当前测试仪器发展的方向之一。In instrument designing or testing system using software instead of hardware as far as possible, namely "software is instrument&quo

2、t;, it is on general computer platform, according to user needs to define and design the instrument test function, its essence is to take full advantage of the latest computer technology to realize and expand the function of the traditional instruments, software, hardware functions of this instrumen

3、t to testing instruments has brought profound changes, so virtual instrument represents one of the developing direction of the current testing instruments.2、虚拟仪器的特点和构成2, the characteristics of virtual instrument and composition2.1虚拟仪器的特点2.1 the characteristics of virtual instrument和传统仪器相比，虚拟仪器具有高效、开

4、放、易用灵 活、功能强大、性价比高、可操作性好等明显优点。Compared with traditional instrument, virtual instrument has high efficiency, open, flexible and easy to use and powerful, cost-effective, good operability and other obvious advantages.2.2虚拟仪器的构成2.2 the composition of virtual instrument虚拟仪器的构建主要从硬件电路的设计、软件开发和设计两个方面考虑。The

5、 construction of virtual instrument is mainly from the hardware circuit design, software development and design two aspects to consider.根据目前我们所完成的测试设备，硬件电路的设计一般是选择现有的各种不同功能的板卡以及信号调理板来 搭建。所选用板卡的功能包括：高速数据采集和信号转换: 信号输出和控制；数据的a/d转换。将具有一种或多种功 能的板卡结合信号调理板组建起来，就能构成任何一种虚拟仪器。例如使用高速数据采集板卡和高速实时数据处理 就能构成1台示波器、1

6、台数字化仪或1台频谱分析仪: 使用数字量信号输入/输出板卡和实时数据处理就能构成1台函数发生器、1台信号源或1台控制器。According to the present we have complete testing equipment, the hardware circuit design of the general is to select the existing various functions of the card and signal conditioning board to build. Chooses the card features include: high

7、speed data acquisition and signal conversion; Signal output and control; Data of the a/d conversion. Combine with functions of one or more of the card signal conditioning board together, will constitute any kind of virtual instrument. For example, using high speed data acquisition board and high-spe

8、ed real-time data processing can constitute one oscilloscope and 1 digitizer or 1 spectrum analyzer; Using digital signal input/output boards can form 1 and real-time data processing function signal generator, 1 or 1 controller.3、虚拟仪器在实际测控系统中的使用3, the application of virtual instrument in the actual

9、measurement and control system3.1虚拟仪器在航空机载电子 测控系统中的使用3.1 virtual instrument application in airborne electronic measurement and control system测控系统在航空机载成件中起着举足轻重的作用，提高和完善测控系统的精度和测试能力对于整个飞机性能 分析具有重要的意义。我们主要完成了基于虚拟仪器的各 型继电器盒、各型开关盒测控系统的编织袋水性油墨测 试。使用数字采集板及工控机并在 labwindows/cvi开发 平台中实现了对整个测试的电压采集、 对各型继电器盒的

10、逻辑状态及延时时间进行输出存储和分析。Measurement and control system in the airborne pieces plays a pivotal role, enhance and improve the precision of measurement and control system and testing capability for the aircraft performance analysis has important significance. We mainly completed each relay box, each model b

11、ased on virtual instrument switch box test measurement and control system. Using a digital acquisition boards and industrial control in labwindows/cvi development platform and implements a voltage acquisition for the entire test, for each relay box of the logic of the state and output delay time for

12、 storage and analysis.测试系统组成3.1.1 test system整个测控系统由美国ni公司的labwindows/cvi8.0,研华的1块pci_175148路数字量输入/输出板,2块pci_1754 64 路数字量输入板、2块pcld_785b 24 通道继 电器输出板、6块pcld_782 24通道光电隔离数字量输入 板,1块pcl_818l 16通道a/d转换板、若干信号调理板及 工控机组成。The whole measurement and control system by the ni Iabwindows/cvi8.0, grind degrees of

13、 1 piece of pci_1751 48 road digital quantity input/output board, 2 piece pci_1754 64 digital tablet, 2 piece pcld_785b 24 channel relay output board, 6 piece of pcld_782 24 digital photoelectric isolation tablet, 1 piece of pcl_818l 16 channel a/d conversion board, number of signal conditioning boa

14、rd and industrial control.测控系统的数据采集和处理采用虚拟仪器测量平台。测控部分主要作用是参和被测产品的控制、测试数据处理和量化,驱动测试数据显示；工控机通过数字量输出板，经继电器输出板变换为被测产品的模拟控制信号；从被测产品采集来的电气逻辑信号经光电隔对旋局部通风机离数 字量输入板转换为数字量信号，通过数字量输入板输至工 控机;另外,利用a/d转换板来显示电压；利用系统时钟来完 成被测产品的时间继电器延时时间的测试。Measurement and control system of data acquisition and processing with virtu

15、al instrument measurement platform. Measurement and control part of the main function is involved in the control of the product under test, test data processing and quantitative, the drive test data display; Industrial computer through digital output board, the relay output board transform for produ

16、cts tested simulation control signal; Measured products collected from electric signal by photoelectric isolated digital logic measure tablet can be converted into digital signal, through the digital quantity input board sent to industrial control; In addition, the use of a/d conversion board to dis

17、play the voltage; Time to finish the products tested the system clock is used to relay delay time test.基于虚拟仪器的航空机载电子系统测控平台3.1.2 the airborne electronic system based on virtual instrument measurement and control platform该平台整体系统采用美国国家仪器公司的虚拟仪器 专用开发平台labwindows/cvi系统。由于cvi在标准c语 言(ansi c)的基础上增加了仪器控制和工具函

18、数库的虚拟 仪器开发软件，它的集成化开发平台、交互式编程方法、 丰富的面板功能和库函数使其自身功能更加强大，使用更加方便,界面完全能够虚拟真实实物进行设计，使得人机对 话界面直观、友好。The platform as a whole system adopts special virtual instrument development platform of the national instruments labwindows/cvi systems. Since cvi (ANSI c) in the standard c language on the basis of increas

19、ed instrument control and tool function library of virtual instrument software development, integrated development platform, interactive programming method of it, the rich palette and library functions to make its functions more powerful, more convenient application, virtual reality interface can co

20、mpletely physical design, makes the man-machine dialogue interface intuitive and friendly.由于测试的产品种类多，归属性强，因此系统测控平台 的用户界面采用下拉菜单式，所需测试的产品一目了然，选 用方便。Due to the test of product variety, strong GuiShuXing, so the system measurement and control platform user interface using the drop-down menu type, requir

21、ed to test the product at a glance, use convenient.3.2基于虚拟仪器的测控平台在测控系统中的使用所使用的几个关键技术3.2 measurement and control platform based on virtual instrument technology application in the measurement and control system used by a few key technology通过采用系统时钟的方法提高软件测时时间3.2.1 improve software test by using the me

22、thod of the system clock time在测试过程中要获得延时继电器的时间，一种方法是采用定时器/计数器板专门进行计数，另一种方法是采用系 统时钟进行计数。由于所需测试的时间为秒级，要求误差为20%,采用后一种方法完全能达到，一是可以节约成本,二是选购的计算 机可不必多配置一个插槽，节省了空间。在程序中使用了以下函数来获取高精度时间，它的精度可以达到毫秒级。In the testing process to get the time delay relay, one approach is to use the timer/counter board dedicated to

23、 count, another method is to use the system clock to count. Due to the required test time for the second level, request error was 20%, using the latter method can fully meet, it is can save the cost, the second is to choose the calculation doesn't need a machine equipped with a slot, more save a

24、 space. In the program using the following function to obtain a high precision time, its precision can reach millisecond.在测控系统中运用了数据库管理技术3.2.2 use database management technology in the measurement and control system由于lab windows/cvi开发平台能够方便使用ni公司开发的sql工具包,使得大量的测试数据能够以数据库的 形式存储、查询。Due to lab Windows/

25、cvi development platform can convenient use SQL kit developed by ni company, makes a lot of test data can be stored in the form of a database, query.在测控系统中，可以通过所设置的产品名称、件号、 时间、测试结果、温湿度、试验者、质控者等字段来进行 保存,完成了一套产品的履历记录，通过查询产品的件号、 时间等就可以调出每个产品的测试记录，这样就解脱了人工管理的诸多不便，提高了工作效率。In measurement and control system, can be set by the product name, part number, time, temperature and humidity test results, and participants, quality control and other fields to save, to complete a set of product record record, by