【正文】 easily pleted the parameters of the test, analysis, printing and other functions. 3. the instrument hardware design Virtual hardware equipment, including puter hardware and equipment hardware consists of two parts, of which only equipment needed is the hardware design. The The hardware equipment from the main sensors, signal the same token, data acquisition cards and four puter parts. To cover a larger range and meet certain measurement accuracy, the choice of different parameters measuring range of more than sensors. For example, force measurement in the range of 01KN, precision measuring % (FS), should be measured by the upper limit of the four sensors assistance to cover their range. NI signal conditioning devices selected panies ( Nationnal Instruments, National Instruments, is a virtual production equipment ponents wellknown pany) produced a SCX11122 multiplexer, SCX1 a 1122 maximum 16channel, Strain gauge conditioning, thermistor, RTD, thermocouple voltage signal and munication, process control switch the type of signal conditioning. In accordance with the use of the puter is a laptop or desktop, choose different data acquisition board. In order to facilitate the portability of this equipment is used in portable puters. NI data acquisition card is a Ai Corporation DAQCard a 16XE a 50 for 16bit A / D converter sampling rate for single200K, multichannel at 20K. The measurement accuracy of this instrument to percent. 16 of the A / D fully meet this requirement。計(jì)算機(jī)技術(shù)的發(fā)展和應(yīng)用 , 給儀器儀表領(lǐng)域帶來了深刻的變化 , 特別是虛擬儀器的產(chǎn)生和應(yīng)用 , 可以說是儀器領(lǐng)域的一次革命 , 但長期以來 , 不論是在我們的物理教學(xué)活動(dòng)中 , 還是傳統(tǒng)儀器占主導(dǎo)地位 , 計(jì)算機(jī)與測量儀器基本上還處于互不相關(guān)的狀態(tài) , 這必將大大影響我們對于先進(jìn)儀器的了解和掌握 , 因此學(xué)習(xí)一些虛擬儀器的基本知識(shí)是頗必要的。 , 容易實(shí)現(xiàn)升級(jí)、虛擬儀器的硬件結(jié)構(gòu)是相對固定的 , 而軟件卻具有很大的靈活性 , 對軟件或操作系統(tǒng)升級(jí)后 , 虛擬儀器就可以更新、換代。用戶利用 鼠標(biāo)或鍵盤直接在虛擬面板上進(jìn)行操作 , 即可輕松完成各種參數(shù)的測試、分析、打印等功能。數(shù)據(jù)采集卡是 NI公司的 DAQCard一 Ai一 16XE一 50, 為 16位 A/D轉(zhuǎn)換器采樣速率單通道方式為 200K, 多通道時(shí)為 20K。本儀器的面板布局合理 , 易于操作 , 具有高度的人機(jī)交互性 , 用戶的每一步操作都能得到提示和即時(shí)響應(yīng) , 并提供在線助。隨著計(jì)算機(jī)在我國的進(jìn)一步普及 , 虛擬儀器必將得到越來越廣泛的應(yīng)用 , 也必將對物理教學(xué)作出更大的貢獻(xiàn)。s desktop dualchannel digital storage oscilloscope HP54603B functions, and instrumental analysis and processing functions have expanded. Instrument main features include: dualchannel signal input, trigger control, access control, timebase control, waveform display, parameter automatic measurement, spectrum analysis, waveform, such as storage and playback. The virtual digital oscilloscope also provides work interface, allowing the adoption of TCP / IP protocol work sharing or remote control apparatus. Table 1 is the virtual digital oscilloscope with HP54603B function table. In addition to financial reasons make the selected sampling rate data acquisition card HP54603B below, this virtual oscilloscope display, measurement, analysis, storage and external connections so as not less than even higher than HP54603B 2 Software Design and Implementation Software Development Environment Virtual Digital Oscilloscope software design using advanced graphical programming language LabVIEW for Windows98/NT. The main features of LabVIEW programming is divided into a number of virtual instruments basic function modules (equivalent to hardware design of integrated circuits), the representative pin module input / output interface. Programmers through interactive means, the use of graphical block diagram design method to plete the virtual instrument measurement and analysis of the logic and functional design. LabVIEW program design process and design equipment people very close to the thinking process, the program block diagram on the realization of the program code function, to avoid a general idea of program design from the diagram to the process by cutting red tape. Another advantage of LabVIEW programming is the software interface design and functional design to an independent open, modify interactive interface to the entire process without debugging, which is designed as instruments of such a plicated operation panel in terms of manmachine interface is very convenient. LabVIEW also provides a function for users to expand functionality, the use of LabVIEW in the Code Interface Node (CIN), can call using the traditional C programming language to write code。 ? Display Unit choice, provided the eight kinds of units. data storage and playback module Krupp magic button controls for data storage Main panel provides two file name input box, the former a signal waveform data file name input box, after a sampling period for the file name input box, these two documents from the write function and load sharing functions. From the floppy or hard disk to read the data with realtime acquisition of data, can automatically and display waveform parameter measurement and retained in the display window (display mode can be set to any of the three models a), may also need to set up in accordance with spectral analysis. The main control structure Measurement and Control Structure Through logical button measuring control whether or not to conduct measurement。數(shù)字示波器 。因此，我們可以設(shè)想在必要的數(shù)據(jù)采集硬件和通用計(jì)算機(jī)支持下，通過軟件設(shè)計(jì)實(shí)現(xiàn)儀器的全部功能，這就是虛擬儀器設(shè)計(jì)的核心。將它們安裝在一臺(tái)運(yùn)行 Windows95/98/NT 的 PC 機(jī)上（建議配置在 PENTIUMⅡ ／ 233 以上），即 構(gòu)成一個(gè)功能強(qiáng)大的可存儲(chǔ)數(shù)字示波器。實(shí)際測量時(shí)輸入信號(hào)通過 BNC 接頭從輸入端子進(jìn)入數(shù)據(jù)采集卡進(jìn)行采集。 LabVIEW 程序設(shè)計(jì)過程與人們設(shè)計(jì)儀器的思維過程十分相近，程序框圖就實(shí)現(xiàn)了程序代碼功能，避免了一般程序設(shè)計(jì)從框圖構(gòu)思到程序表示的繁瑣。通道選擇主要控制單通道或雙通道測量； 可實(shí)現(xiàn)的頻譜分析控制包括： 自動(dòng)調(diào)整掃描率控制結(jié)構(gòu) 由邏輯按鍵組 “自動(dòng) ”、 “手動(dòng) ”來控制是自動(dòng)調(diào)整掃描率還是手動(dòng)調(diào)整掃描