基于單片機(jī)的超聲波檢測(cè)設(shè)計(jì)畢業(yè)論文

摘   要

隨著社會(huì)經(jīng)濟(jì)的發(fā)展交通運(yùn)輸業(yè)日益興旺，汽車的數(shù)量在大副攀升。交通擁擠狀況也日趨嚴(yán)重，撞車事件屢屢發(fā)生，造成了不可避免的人身傷亡和經(jīng)濟(jì)損失，針對(duì)這種情況，設(shè)計(jì)一種響應(yīng)快，可靠性高且較為經(jīng)濟(jì)的汽車防撞預(yù)警系統(tǒng)勢(shì)在必行，超聲波測(cè)距法是最常見(jiàn)的一種距離測(cè)距方法，本文介紹的就是利用超聲波測(cè)距法設(shè)計(jì)的一種倒車防撞報(bào)警系統(tǒng)。
論文的內(nèi)容是基于AT89C51單片機(jī)倒車防撞系統(tǒng)的設(shè)計(jì)，主要是利用超聲波的特點(diǎn)和優(yōu)勢(shì)，將超聲波測(cè)距系統(tǒng)和AT89C51單片機(jī)結(jié)合于一體，設(shè)計(jì)出一種基于AT89C51單片機(jī)的倒車防撞報(bào)警系統(tǒng)。該系統(tǒng)采用軟、硬件結(jié)合的方法，具有模塊化和多用化的特點(diǎn)。
論文概述了超聲波檢測(cè)的發(fā)展及基本原理，闡述了超聲波傳感器的原理及特性。對(duì)于系統(tǒng)的一些主要參數(shù)進(jìn)行了討論，并且在介紹超聲波測(cè)距系統(tǒng)功能的基礎(chǔ)上，提出了系統(tǒng)的總體構(gòu)成。通過(guò)多種發(fā)射接收電路設(shè)計(jì)方案比較，得出了最佳設(shè)計(jì)方案，并對(duì)系統(tǒng)各個(gè)設(shè)計(jì)單元的原理進(jìn)行了介紹。對(duì)組成各系統(tǒng)電路的芯片進(jìn)行了介紹，并闡述了它們的工作原理。論文介紹了系統(tǒng)的軟件結(jié)構(gòu)，通過(guò)編程來(lái)實(shí)現(xiàn)系統(tǒng)功能。最后，通過(guò)對(duì)系統(tǒng)的誤差分析，給出了系統(tǒng)的改進(jìn)方案。

關(guān)鍵字：?jiǎn)纹瑱C(jī)  超聲波  AT89C51
 

Abstract

Is day by day prosperous along with the social economy development transportation shipping industry, the automobile quantity climbs in the first mate. Traffic congestion condition also day by day serious, the collision event occurred repeatedly, has caused the inevitable person casualties and the economic loss, in view of this kind of situation, designed one kind to respond quickly, the reliability was high also a more economical automobile guards against hits the early warning system imperative, the ultrasonic wave range finding was the most common one distance range finder method, this article introduces is guards against using the ultrasonic wave range finding design one kind of back-draft hits the alarm system.
The paper is based on the contents of the AT89C51 monolithic integrated circuit reverse collision avoidance system design, mainly using ultrasound features and advantages, ultrasound ranging system and the integration with the integration AT89C51 monolithic integrated circuit, AT89C51 monolithic integrated circuit based on the design of a reverse collision avoidance warning systems. The system used software and hardware integrated approach of a modular and multi-use characteristics.
The paper outlines the development and the basic principles of ultrasound tests on the principles and characteristics of ultrasound sensors. Some of the main parameters for the system were discussed, and introducing ultrasonic ranging system functions basis, the overall composition of the system. Through multiple launch reception circuit design comparison, the best designed programme drawn, and various system design modules principles introduced. On the composition of the system circuit chip introduced and elaborated the principles of their work. Papers introduced system software architecture, through programming to achieve system function. Finally, through the analysis of system error, giving the system improvement programme.
Key word：monolithic integrated circuit；ultrasonic wave；AT89C51

目    錄

第1章  緒論 1
1.1  超聲檢測(cè)發(fā)展綜述 1
1.2  論文主要內(nèi)容和章節(jié)安排 3
1.3  本設(shè)計(jì)時(shí)間安排 3
第2章  超聲波測(cè)距原理 5
2.1  超聲波傳感器介紹 5
2.1.1  超聲波傳感器特性 6
2.2  超聲波檢測(cè)概述 7
2.2.1  超聲探傷 8
2.3  超聲測(cè)距原理及實(shí)現(xiàn)  9
第3章  單片機(jī)超聲波測(cè)距系統(tǒng)構(gòu)想 10
3.1  超聲波測(cè)距系統(tǒng)總體方案 10
3.2  系統(tǒng)主要參數(shù)考慮 11
3.2.1  傳感器指向角 11
3.2.2  測(cè)距儀的工作頻率 12
3.2.3  聲速 12
3.2.4  發(fā)射脈沖寬度 12
3.2.5  測(cè)量盲區(qū) 13
第4章  單片機(jī)倒車防撞報(bào)警系統(tǒng)各組成單元方案設(shè)計(jì) 14
4.1  發(fā)射接收電路方案設(shè)計(jì) 14
4.2  顯示報(bào)警單元方案設(shè)計(jì) 22
4.2.1  系統(tǒng)顯示電路設(shè)計(jì) 22
4.2.2  系統(tǒng)報(bào)警電路設(shè)計(jì) 23
4.3  單片機(jī)復(fù)位電路 24
4.4  時(shí)鐘電路 25
4.5  穩(wěn)壓電源 25
第5章  系統(tǒng)硬件及軟件實(shí)現(xiàn) 27
5.1  單片機(jī)硬件介紹 27
5.1.1  單片機(jī)AT89C51介紹 27
5.1.2  8155芯片介紹 28
5.1.3  74LS244芯片介紹 29
5.1.4  74LS06芯片介紹  30
5.2  運(yùn)算放大器 31
5.3  LM567芯片介紹 32
5.4  探頭UCM介紹  33
5.5  系統(tǒng)軟件結(jié)構(gòu)  34
5.5.1  主程序  34
5.5.2  顯示子程序和蜂鳴報(bào)警子程序  37
第6章  系統(tǒng)誤差分析及改進(jìn) 39
6.1  誤差產(chǎn)生原因分析 39
6.1.1  溫度對(duì)超聲聲速的影響 39
6.1.2  回波檢測(cè)對(duì)時(shí)間測(cè)量的影響 40
6.1.3  超聲傳感器所加脈沖電壓對(duì)測(cè)量范圍和精度的影響 40
6.2  針對(duì)誤差產(chǎn)生原因的系統(tǒng)改進(jìn)方案 40
參考文獻(xiàn) 42
致謝 43