基于虚拟仪器的微位移测量系统的研制

测控论文编号:CK056   论文字数:11516,页数:24

目 录

1  绪论 2
1.1研制虚拟仪器的意义 2
1.2虚拟仪器的研究现状 3
1.3课题来源及主要研究工作 3
2  微位移测量系统的电路设计与分析 4
2.1总体方案设计 4
2.1.1设计原理和原理框图 4
2.1.2电感传感器工作原理 5
2.2前置处理电路的设计与分析 6
2.2.1  激励电源的设计与分析 6
2.2.2电阻—电感测量电桥的构成与分析 7
2.2.3震荡器的设计与分析 8
2.2.4相敏检波电路的设计与分析 8
2.2.5带通滤波电路的设计与分析 9
2.3  A/D转换电路的设计与数据采集 11
2.3.1  A/D转换 11
2.3.2 数据的传输与采集 13
2.4减少误差的设计和分析 14
2.4.1系统的抗干扰设计 14
2.4.2.随机误差的消除 15
2.4.3.系统误差的处理 15
2.5元器件选择，电路图 16
2.5.1.元器件的选择 16
2.5.2电路图 16
2.6  虚拟微位移测量系统的软件设计 17
2.7本章小结 18
3  总结 19
致谢 20

摘  要
 
 虚拟仪器是二十世纪八十年代中期出现的一种新型的仪器模式。它以计算机硬件为平台，由传感器、模块化硬件接口卡以及测量软件库构成虚实并存的测量系统，是仪器智能化、集成化、远程化以及测控一体化设计的典型范例。目前，用于电量测量的虚拟仪器已极为普遍，然而，用于非电量测量的虚拟仪器相对较少，特别是在几何量测量领域，其虚拟仪器则几乎没有见到。为此，我们对位移量测量仪器的虚拟化进行了研究，并制作了一套虚拟电感测微仪。
 本论文首先阐述了课题的目的和意义，分析了国内外对虚拟仪器的研究状况。然后，对差动电感传感器的工作原理做了详细的分析，并在此基础上设计了用于虚拟电感测微仪的信号处理板、A/D卡以及测量软件。
 实验结果表明：在200m、150m、100m、50m范围内，仪器的绝对线性度误差分别为0.62m、0.30m、0.28m和0.16m，相对线性度误差分别为1.6‰、0.9‰、1.5‰和1.6‰。仪器的示值分散度为0.16m，标准偏差为0.09m。本仪器已基本达到设计要求，具有较大的测量范围和高分辨率以及很好的精密度，具备实用及推广价值。
关键词：虚拟仪器  位移测量  电感式传感器

Abstract
    Virtual Instrument (VI) was put forward as a novel instrument mode in the middle of the 1980s. It is a virtual-real measuring system based on PC computer and composed of sensors, modularized hardware interface cards and measurement software packages. It is a typical model for instrument design with intellectualizing, integrating, long-distance, and measurement & control as a whole. At present, VI for electrical measurement has been widely used. However, those for non-electric measurement are rarely reported, especially for geometrical measurement covering extensive fields and many sorts of sensors.To solve the problem, we reasearched virtual technology of geometrical measurement and developed an Inductive Micro-Displacement Instrument (IMDI) based on virtual technology.
     First,the purpose and significance of the project are introduced in this dissertation, and the status of the art in virtual measurement at home and abroad is also described. Subsequently, the working principle of inductive sensor and the design of the signal process card of the IMDI are discussed. The dissertation also provides the detailed design schemes of pre-processing circuit and A/D sampling card based on ISA bus of the virtual IMDI.
 The result shows that, in the range of 200m、150m、100m and 50m, the absolute linearities of the instrument are 0.62m、0.30m、0.28m and 0.16m respectively and the relative linearities are 1.6‰、0.9‰、1.5‰和1.6‰ respectively.The dispersion of the instrument is 0.16m and the standard deviation is 0.09m.The virtual system has achieved design requirement, it has large measurement range, high resolution, good precision, and is worth to extend.

Keywords：Virtual Instrument (VI), Displacement measurement, Inductance    sensor