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【摘要】：激光測距具有測量范圍遠、速度快、精度高、抗干擾能力強等優(yōu)點,因此在測繪、建筑業(yè)、交通、工業(yè)及航空航天等各領域得到了廣泛的應用。激光測距分為脈沖法和相位法兩種,本文通過對激光測距的研究,旨在提供一種低成本、多功能、無線化的激光測距儀。本文首先介紹了激光測距的原理,選擇了脈沖法作為本系統(tǒng)的測距方法,接著提出了系統(tǒng)的總體設計方案,設計的激光測距系統(tǒng)由激光發(fā)射電路、激光脈沖接收處理電路、時間間隔測量電路、基于TMS320F2812的主控制電路、Zigbee無線收發(fā)模塊及軟件系統(tǒng)組成,能夠?qū)崿F(xiàn)對目標物距離、面積、體積及高度的測量。其中激光發(fā)射電路部分采用了小功率、對人眼安全的半導體激光二極管作為系統(tǒng)的激光器,使用D觸發(fā)器設計了激光驅(qū)動電路。激光脈沖接收處理電路包含回波信號接收處理電路和內(nèi)部激光脈沖接收處理電路兩個部分,選用PN光電二極管作為光電探測器,設計了前置電流電壓轉(zhuǎn)換電路實現(xiàn)了對光電二極管光電流的轉(zhuǎn)換,針對信號信噪比低的特點,設計了低噪聲的放大電路和濾波電路使得信噪比大幅提高,并對激光脈沖的開始時刻和回波信號的返回時刻進行了準確地鑒別。在時間間隔測量部分,采用時間轉(zhuǎn)換數(shù)字技術(shù)設計了高精度的計時電路對激光脈沖的飛行時間進行了準確測量。主控制電路部分主要由TMS320F2812及其外圍電路構(gòu)成,負責掃描功能選擇按鍵、控制激光發(fā)射電路產(chǎn)生激光脈沖、控制計時電路測量激光飛行時間、計算和處理數(shù)據(jù)、控制串口發(fā)送測量結(jié)果及液晶顯示單元顯示測量結(jié)果。Zigbee無線收發(fā)模塊實現(xiàn)了測量數(shù)據(jù)的無線傳輸,軟件系統(tǒng)主要包括數(shù)據(jù)測量程序、無線收發(fā)模塊程序及上位機接收系統(tǒng),上位機軟件采用C#語言設計,方便用戶查看數(shù)據(jù)和遠程操作。本文最后對激光測距系統(tǒng)進行測試并提出了一種可降低測量誤差的數(shù)據(jù)擬合算法,測量結(jié)果表明系統(tǒng)基本達到了設計的要求,具有成本低廉、使用方便、精度較高的特點和良好的應用前景。
[Abstract]:Laser ranging has been widely used in many fields such as surveying, construction, traffic, industry, aerospace and so on, because of its advantages such as wide range of measurement, high speed, high precision, strong anti-jamming ability and so on. Laser ranging can be divided into pulse method and phase method. The purpose of this paper is to provide a low cost, multi-function, wireless laser rangefinder through the research of laser ranging. This paper first introduces the principle of laser ranging, selects the pulse method as the ranging method of the system, and then puts forward the overall design scheme of the system. The laser ranging system is designed by laser transmitting circuit, laser pulse receiving and processing circuit. The time interval measuring circuit, the main control circuit based on TMS320F2812, the Zigbee wireless transceiver module and the software system, can measure the distance, area, volume and height of the object. In the part of laser emission circuit, the laser drive circuit is designed by using D flip-flop. The laser pulse receiving and processing circuit includes two parts: the echo signal receiving and processing circuit and the inner laser pulse receiving processing circuit. The PN photodiode is selected as the photodetector. The photocurrent conversion of photodiode is realized by designing the preposition current-voltage conversion circuit. Aiming at the characteristics of low signal-to-noise ratio, a low-noise amplifier circuit and filter circuit are designed to improve the signal-to-noise ratio (SNR) greatly. The initial time of the laser pulse and the return time of the echo signal are accurately identified. In the part of time interval measurement, time conversion digital technology is used to design a high precision timing circuit to accurately measure the time of flight of laser pulse. The main control circuit is composed of TMS320F2812 and its peripheral circuit, which is responsible for selecting keys for scanning function, controlling laser emission circuit to generate laser pulse, controlling timing circuit to measure laser flying time, calculating and processing data. The Zigbee wireless transceiver module realizes the wireless transmission of the measurement data. The software system mainly includes the data measurement program, the wireless transceiver module program and the host computer receiving system. PC software is designed in C # language to facilitate users to view data and remote operation. Finally, the laser ranging system is tested and a data fitting algorithm is proposed, which can reduce the measurement error. The measurement results show that the system basically meets the requirements of the design, with low cost and easy to use. High precision and good application prospect.
【學位授予單位】：南京信息工程大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TN249

【參考文獻】

相關期刊論文 前1條

1 管敏杰;趙冬娥;;基于PIN型光電轉(zhuǎn)換電路的噪聲研究[J];電子測試;2012年02期

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本文編號：2385209