動態(tài)應(yīng)變測試儀的研究與設(shè)計（本科畢業(yè)論文設(shè)計）
摘 要

隨著計算機(jī)技術(shù)的發(fā)展，儀器工業(yè)正在經(jīng)歷一場巨變。計算機(jī)強(qiáng)大的數(shù)據(jù)處理能力，使其可以在數(shù)據(jù)采集、后處理和表達(dá)中任意一個方面提升儀器性能。虛擬式動態(tài)應(yīng)變儀正是利用虛擬儀器的優(yōu)勢，并結(jié)合PC標(biāo)準(zhǔn)配置——聲卡，實現(xiàn)成本低廉、適應(yīng)性強(qiáng)、精度較高的動態(tài)應(yīng)變測試。
本文介紹了虛擬儀器基本框架和總體設(shè)計思路。在此基礎(chǔ)上，提出了基于PC聲卡的虛擬動態(tài)應(yīng)變測試儀的系統(tǒng)設(shè)計方案。文中重點講解了該動態(tài)應(yīng)變測試儀各模塊的詳細(xì)設(shè)計，包括數(shù)據(jù)采集、濾波、數(shù)據(jù)管理、時域分析和頻域分析等模塊，并給出了具體的設(shè)計方法和設(shè)計結(jié)果。
本設(shè)計以C++ Builder為軟件開發(fā)平臺，運用面向?qū)ο蟮木幊淘O(shè)計方法，開發(fā)了虛擬式動態(tài)應(yīng)變測試儀。該測試儀主要實現(xiàn)了應(yīng)變信號的采集、濾波、顯示、存儲及頻譜分析等功能，基本能滿足一般測試要求。最后對本次設(shè)計做了總結(jié)，對進(jìn)一步研究做出展望。

關(guān)鍵詞：虛擬儀器，動態(tài)應(yīng)變測量，聲卡，軟件開發(fā)

Abstract

The instrumentation industry is undergoing a variety of exciting changes as a result of the development of PCs. The computer can enhance the function of instrument in any of the areas in data acquisition, analysis, and performance. Combined with PC-standard configuration-sound card, the virtual dynamic strain measurement instrument take the advantages of virtual instrument, in order to achieve low costs, strong adaptability and high precision of the dynamic strain test.
This paper describes the basic framework and design ideas of virtual instrument. On this basis, we have proposed a virtual PC-based sound card dynamic strain measurement instrument in the system design. The article focuses on the virtual dynamic strain measurement instrument modules of the detailed design, including data collection, filtering, data management, time-domain analysis and frequency domain analysis module, and gives the specific design and design results.
This design uses object-oriented programming design method to develop the virtual dynamic measurement instrument at C++ Builder development platform. The main function of the measure instrument is to make the collection, filtering, display, storage, and spectral analysis of the strain signals come true, which can meet the basic requirements of general tests. Finally, we have made a conclusion and have proportion for further study.

Key words: virtual instrument, dynamic strain measurement, sound card, software development


目 錄

中文摘要 Ⅰ
英文摘要 Ⅱ
1 緒論 1
1.1 應(yīng)變測試的意義 1
1.2 應(yīng)變電測技術(shù)概述 1
1.2.1電阻應(yīng)變傳感器的發(fā)展概況 1
1.2.2應(yīng)變測試儀的發(fā)展概況 2
1.3 虛擬儀器技術(shù)概述 2
1.4 本課題的研究意義 3
2 虛擬應(yīng)變測試系統(tǒng)設(shè)計的理論基礎(chǔ) 4
2.1 電阻應(yīng)變電測技術(shù) 4
2.1.1 電阻應(yīng)變片 4
2.1.2 應(yīng)變測試電路 6
2.2 虛擬儀器技術(shù) 10
2.2.1 虛擬儀器的基本功能 10
2.2.2 虛擬儀器的結(jié)構(gòu) 11
2.3 測試信號處理技術(shù) 13
2.3.1 信號數(shù)字分析的基本步驟 13
2.3.2 連續(xù)時間信號的采樣 13
2.3.3信號的時域截斷、泄漏與窗函數(shù) 16
2.3.4 數(shù)字信號頻域分析基礎(chǔ) 17
3 系統(tǒng)的硬件設(shè)計 19
3.1硬件方案設(shè)計 19
3.2 數(shù)據(jù)采集部分 19
3.2.1聲卡的基本結(jié)構(gòu) 19
3.2.2聲卡的主要技術(shù)參數(shù) 20
3.2.3聲卡的選用 21
3.3 放大器的選用 21
3.3.1磁帶錄放機(jī)放大電路 22
3.3.2耦合電路 23
4 系統(tǒng)的軟件設(shè)計 24
4.1軟件方案設(shè)計 24
4.2數(shù)據(jù)采集模塊 24
4.2.1 相關(guān)Windows API函數(shù) 24
4.2.2聲卡數(shù)據(jù)采集的實現(xiàn)過程 26
4.2.3程序設(shè)計 27
4.3數(shù)據(jù)后處理模塊 30
4.3.1數(shù)字濾波 30
4.3.2數(shù)據(jù)管理 31
4.3.3時域分析 32
4.3.4頻域分析 34
5 系統(tǒng)功能模塊測試 35
5.1 系統(tǒng)功能概要 35
5.2 數(shù)據(jù)采集模塊測試 35
5.3 濾波模塊測試 35
5.4 標(biāo)定模塊測試 .35
5.5 時域分析模塊測試 35
5.6 頻域分析模塊測試 35
6 結(jié)論 39
參考文獻(xiàn) 43
附錄A：圖形顯示 45