发布时间 : 星期一 文章数据采集系统-毕业论文更新完毕开始阅读
虚拟仪器设计-数据采集系统 摘 要
虚拟仪器由通用仪器硬件平台（简称硬件平台）和应用软件两大部分构成。硬件平台主要完成对被测信号的进行调理和采集。仪器硬件可以是插入式数据采集卡及必要的外围电路（含信号调理电路、A/D转换器、数字I/O、定时器、D/A转换器等），或者是带标准总线接口的仪器，如GPIB、VXI、PXI、STD、PCI总线仪器和网络化仪器等。
目前市场上的A/D采集卡和数据采集卡以及带标准总线接口的仪器等，其价格均不菲，以毕业设计的目的来说，性价比以及实用程度显的不高。
进而考虑到计算机中的声卡本身就是一个A/D，D/A的转化装置，具有16位的量化精度、数据采集频率是44.1kHz，完成可以满足特定应用范围内数据采集的需要，个别性能指标还优于商用数据采集卡，而价格却为商用数据采集卡的十分之一或者几十分之一，在设计实验中完全可以满足要求。
因此在本设计中，数据采集装置主要基于声卡和labview模拟数据采集。利用声卡实现对数据的采集，制作成一个简易的数据采集系统，能够实现数据采集、模拟采集数据、波形显示、进行低频滤波四大功能。
关键词：虚拟仪器；数据采集；声卡
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Virtual Instrument Design - Data
Acquisition System
Abstract
Virtual Instrument by the General Instrument hardware platform (the hardware platform) and consisted of two major applications. The main hardware platform to complete the conduct of the measured signal conditioning and acquisition. Hardware equipment can be a plug-in data acquisition card and the necessary peripheral circuits (including the signal conditioning circuits, A / D converter, digital I / O, timer, D / A converters, etc.), or with the standard bus interface equipment, such as GPIB, VXI, PXI, STD, PCI bus devices and network equipment and so on.
Currently on the market A / D acquisition card and data acquisition cards, as well as the standard bus interface with the equipment, their prices are expensive to design for the purposes of graduation, as well as the usefulness of the significant cost of not very high.
To take into account the computer's sound card itself is an A / D, D / A conversion devices, with 16-bit quantization precision, data acquisition frequency is 44.1kHz, completed within the scope of application to meet the specific needs of data collection, individual also better than the commercial performance data acquisition card, and the price of commercial data acquisition card for one-tenth or a few one-tenth of the experiment in the design to meet the requirements completely.
Therefore, in this design, data acquisition device is mainly based on the sound card and analog data acquisition labview. The use of sound to achieve the data collection, to create a simple data acquisition system, to achieve data acquisition, analog data acquisition, waveform display, the four major functions for low-frequency filter.
Keywords: virtual instrument; data acquisition; sound card
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目 录
1 绪论 ...................................................................... 1 1.1 虚拟仪器概述 .......................................................... 1
1.1.1 虚拟仪器的产生 .................................................... 1 1.1.2 虚拟仪器的概念 .................................................... 1 1.1.3 虚拟仪器的构成 .................................................... 2 1.2 虚拟仪器的发展趋势 .................................................. 2 1.3本文的研究内容 ........................................................ 3 2 数据采集系统的设计 ........................................................ 5 2.1 LABVIEW软件创建过程 .................................................... 5 2.2 设计方案的比较 ........................................................ 6 2.2.1 软件比较 .......................................................... 6 2.2.2 声卡采集数据的特点 ................................................ 7 3 软件模块的设计 ........................................................... 11 3.1 程序的流程图 ......................................................... 11 3.2 程序的结构图 ......................................................... 12 3.3 LABVIEW 简介 ......................................................... 12 3.3.1 G语言简介 ........................................................ 12 3.3.2 LABVIEW 程序组成 ................................................. 13 3.4 数据采集和处理模块 ................................................... 14 3.4.1声音输入配置虚拟仪器 .............................................. 15 3.4.2声音输入读取虚拟仪器 .............................................. 17 3.4.3声音输入清除虚拟仪器 .............................................. 18 3.5 数据模拟模块 ......................................................... 20 3.6 低通滤波模块 ......................................................... 22 3.7 波形显示模块 ......................................................... 23 3.8 小结 ................................................................. 23 4 程序设计显示 ............................................................. 25 4.1 程序的使用方法 ....................................................... 25 4.1.1 程序的环境 ....................................................... 25 4.1.2 声卡配置 ........................................................ 25 4.2 程序的总框图 ......................................................... 26 4.3 程序的调试结果 ....................................................... 26 4.3.1声卡采集数据的结果 ................................................ 26 4.3.2模拟采集数据的结果 ................................................ 27 4.4 小结 ................................................................. 29 5 设计中遇到的问题 ......................................................... 30 6 总结与展望 ............................................................... 31 参考文献 ................................................................... 32
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致 谢 ...................................................................... 33
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