【正文】 ........ 1 課題設(shè)計(jì)的研究現(xiàn)狀 ........................................................................................................ 1 課題設(shè)計(jì)的任務(wù)和要求 .................................................................................................... 2 課題設(shè)計(jì)的任務(wù) .......................................................................................................... 2 課題設(shè)計(jì)的要求 .......................................................................................................... 2 選題的意義 ........................................................................................................................ 3 研究?jī)?nèi)容及論文構(gòu)成 ........................................................................................................ 3 2 超聲波測(cè)距原理 .................................................................................................................... 5 超聲波簡(jiǎn)介 ........................................................................................................................ 5 超聲波的聲學(xué)特性 ...................................................................................................... 5 超聲波的發(fā)生原理 ...................................................................................................... 6 超聲波傳感器的原理與特性 ............................................................................................ 7 原理 .............................................................................................................................. 7 特性 .............................................................................................................................. 9 超聲波測(cè)距儀的測(cè)距原理 ................................................................................................ 9 單片機(jī)最小系統(tǒng) ........................................................................................................ 11 超聲波發(fā)射電路 ........................................................................................................ 12 超聲波接收電路 ........................................................................................................ 13 超聲波測(cè)距儀顯示電路 ............................................................................................ 15 本章小結(jié) .......................................................................................................................... 15 3 超聲波測(cè)距系統(tǒng)軟件設(shè)計(jì) .................................................................................................... 17 超聲波設(shè)計(jì)概述 .............................................................................................................. 17 主程序流程圖 .................................................................................................................. 18 定時(shí) /計(jì)數(shù)器 T0/T1 定時(shí)程序流程圖 ............................................................................. 20 方式控制寄存器 TMOD.......................................................................................... 20 控制寄存器 TCON .................................................................................................. 21 定時(shí)器 T0 流程圖 ...................................................................................................... 21 定時(shí)器 T1 中斷服務(wù)程序流程圖 .............................................................................. 22 外部中斷服務(wù)程序流程圖 .............................................................................................. 23 顯示程序流程圖 .............................................................................................................. 23 計(jì)算程序流程圖 .............................................................................................................. 24 4 電路調(diào)試及誤差分析 .......................................................................................................... 26 系統(tǒng)軟件的調(diào)試 .............................................................................................................. 26 系統(tǒng)的軟硬件串聯(lián)調(diào)試 .................................................................................................. 28 系統(tǒng)的誤差分析 .............................................................................................................. 30 聲速引起的誤差 ........................................................................................................ 31 單片機(jī)時(shí)間分辨率的影響 ........................................................................................ 31 隨機(jī)誤差 .................................................................................................................... 32 提高測(cè)距精度的方法 ...................................................................................................... 32 本章小結(jié) .......................................................................................................................... 33 結(jié) 論 ........................................................................................................................................ 34 致 謝 ........................................................................................................................................ 35 參考文獻(xiàn) :................................................................................................................................... 36 附錄： ........................................................................................................................................ 37 1 1 緒 論 課題設(shè)計(jì)的研究現(xiàn)狀 當(dāng)我們的測(cè)距技術(shù)日漸趨于成熟，我們對(duì)測(cè)距的精度要求也日漸嚴(yán)苛，傳統(tǒng)的測(cè)距技術(shù)在某些場(chǎng)合已經(jīng)不能夠滿足人們的需要， 如在井道，水位，管道等的長(zhǎng)度 測(cè)量方面，傳統(tǒng)的測(cè)距方式已然不再適用。超聲波有兩個(gè)特點(diǎn)，一個(gè)是能量大，一個(gè)是沿直線傳播，它的應(yīng)用就是按照這 兩個(gè)特點(diǎn)展開的。 關(guān)鍵詞 ：超聲波測(cè)距儀 ,單片機(jī) Thesis: ultrasonic range finder (software) Specialty: Automation Undergraduate: (Signed) __________ Instructor: (Signed) __________ ABSTRACT Ultrasonic Ranging is a noncontact optical measurement method which has been widely applied in recent years. It has the advantages of measuring convenience, not be the object produce damage. Obvious fe