專業(yè)英語unite16專題省名師優(yōu)質(zhì)課賽課獲獎?wù)n件市賽課一等獎?wù)n件

UNIT16Transducers(Sensors)傳感器第1頁游戲很好玩，工作原理是什么？Wii健身運(yùn)動第2頁觸摸屏是怎么感知？第3頁空隙隔離點(diǎn)保護(hù)膜內(nèi)金屬層玻璃上電阻層觸摸屏結(jié)構(gòu)這里觸摸屏就是一個傳感器第4頁搖擺你手機(jī)使用者翻動手機(jī)選擇“響鈴”或“震鈴”；搖擺手機(jī)變換不一樣鈴聲和游戲；音樂和壁紙伴隨人們動作而改變。傳感器第5頁身邊傳感器CCD熱敏電阻傳聲器溫控器第6頁力傳感器溫度開關(guān)第7頁試驗(yàn)室

傳感器第8頁無線傳感器結(jié)點(diǎn)工業(yè)監(jiān)測與控制產(chǎn)品檢測天然氣壓力監(jiān)測第9頁什么是傳感器狹義地定義：能夠?qū)⑼饨绶请娦盘?，按一定?guī)律轉(zhuǎn)換成電信號輸出器件或裝置。溫度改變電阻值改變熱敏電阻第10頁16.1IntroductionAtransducerisadevicewhichconvertsthequantity(量)beingmeasuredintoanoptical(光學(xué)),mechanical,ormorecommonly-electricalsignal.Theenergy-conversionprocessthattakesplaceisreferredtoastransduction.傳感器（換能器）是一個將被測量轉(zhuǎn)換為光信號、機(jī)械信號或者更常見電信號裝置。能量轉(zhuǎn)換過程稱之為換能。Unit16Transducers第11頁16.1IntroductionTransducersareclassifiedaccordingtothetransductionprincipleinvolvedandtheformofthemeasurand(被測對象).Thusaresistancetransducer(電阻式傳感器)formeasuringdisplacement(位移)isclassifiedasaresistancedisplacementtransducer.Otherclassificationexamplesarepressurebellows,forcediaphragm,andsoon…Unit16Transducers第12頁16.2TransducerElementsUnit16TransducersAlthoughthereareexception,mosttransducersconsistofasensingelementandaconversionorcontrolelement,asshowninthetwo-blockdiagram(二方框圖)ofFig.16.1.第13頁輔助電源敏感元件轉(zhuǎn)換元件基本轉(zhuǎn)換電路被測量電量敏感元件是直接感受被測量，并輸出與被測量成確定關(guān)系某一物理量元件。轉(zhuǎn)換元件：敏感元件輸出就是它輸入，它把輸入轉(zhuǎn)換成電路參量。基本轉(zhuǎn)換電路：上述電路參數(shù)接入基本轉(zhuǎn)換電路（簡稱轉(zhuǎn)換電路），便可轉(zhuǎn)換成電量輸出。Unit16Transducers第14頁Forexample,diaphragms(振動膜),bellows(波紋管),straintubesandrings(應(yīng)力管和應(yīng)力環(huán)),bourdontubes(布爾登管),andcantilevers(懸臂)aresensingelementswhichrespondtochangesinpressureorforceandconvertthesephysicalquantitiesintoadisplacement.

Unit16Transducers第15頁磁鐵

手柄外環(huán)手柄霍爾元件F2＋－F2F1＋－F1晶體晶體第16頁超聲波傳感器工作原理壓電晶片壓電晶片壓電晶片是一個壓電式傳感元件，它既能夠?qū)C(jī)械能轉(zhuǎn)換為電能，又能夠?qū)㈦娔苻D(zhuǎn)換為機(jī)械能。發(fā)射器接收器第17頁磁鐵

手柄外環(huán)手柄手柄旋轉(zhuǎn)手柄，調(diào)整磁鐵和霍爾元件之間距離，電路輸出對應(yīng)電壓，從而控制車速。磁傳感器——電動車車速控制霍爾元件第18頁[2]…Thisdisplacementmaythenbeusedtochangeanelectricalparametersuchasvoltage(電壓),

resistance(電阻),

capacitance(電容),orinductance(電感).Suchcombinationofmechanicalandelectricalelementsformelectromechanicaltransducingdevicesortransducers.Similarcombinationscanbemadeforotherenergyinputsuchasthermal,photo,magneticandchemical,givingthermoelectric,photoelectric,electromagnetic,andelectrochemicaltransducersrespectively.這個位移可用于轉(zhuǎn)換成電參數(shù)，比如電壓、電阻、電容或電感。這種由機(jī)械和電氣元件組成組合就形成了機(jī)電式傳感器或傳感器。類似組合能夠有其它類型能量輸入，比如熱、光、磁和化學(xué)能，分別組成熱電、光電、電磁和電化學(xué)傳感器。Unit16Transducers第19頁16.3AnalogandDigitalTransducersUnit16TransducersConsiderableexperiencehasbeenaccumulatedwithanalogtransducers,signalconditioning,A/Dconvertersetc.anditisnaturalthatmajorityofcurrentsystemstendtousethesetechniques.[3]…我們在模擬式傳感器、信號調(diào)整器以及模-數(shù)轉(zhuǎn)換器等方面積累了大量經(jīng)驗(yàn)，所以，很自然，多數(shù)現(xiàn)有系統(tǒng)趨向于采取這些技術(shù)。第20頁16.3AnalogandDigitalTransducersUnit16TransducersThistypeoftransducer,ifcoupledtocomputer,doesnotnecessarilyrequirethesameamountofequipment,sincemuchoftheprocessingdonebytheintegralcircuitrycouldbeprogrammedandperformedbythecomputer.這種類型傳感器怎樣連接到計算機(jī)上，就不再需要相同數(shù)量其它設(shè)備，因?yàn)橛煞e分?jǐn)?shù)字電路完成大量信號處理工作完全能夠由計算機(jī)編程完成。第21頁Coded-digitalDigitalAnalogSignalTypesInwhichtheparameterofthesystemtobemeasuredalthoughinitially(最初)derived(源于)inananalogformbyasensor,isconvertedtoanelectricalanalog,eithervoltageorcurrent.Someaveragingusuallyoccurs,eitherbydesignorinherent(固有)inthemethodsadopted.Inwhichaparalleldigitalisgenerated,eachbitradix-weightedaccordingtosomepredeterminedcode.[4]Thesearereferredtoasdirectdigitaltransducers.Inwhichafunction,suchasmeanrateofarepetitivesignal,isameasureoftheparameterbeingmeasured.Thesearesubsequentlyreferredtoasfrequency-domaintransducers.Unit16Transducers第22頁16.3AnalogandDigitalTransducersUnit16TransducersThemostpopularoftheseareoutsynchros(同時器),andsimilardeviceswhichproduceamodulatedoutputofacarrierfrequency(載頻調(diào)制輸出).第23頁16.3AnalogandDigitalTransducersUnit16TransducersForordinaryanaloguse,thisoutputhastobedemodulated(解調(diào))toprovideaDCsignalwhosemagnitude(主要性)andsignrepresentsanydisplacementofthetransducer’smovingelement.對于普通模擬用途，這種輸出必須解調(diào)，以提供一個其大小和符號能代表傳感器運(yùn)動元件位移直流信號。第24頁16.3AnalogandDigitalTransducersUnit16TransducersTheusualdisadvantageofthesesystemisthattheinertia(慣性)oftheinstrumentandencoderoftenlimitsthespeedofresponseandthereforetheoperationfrequencies.這些裝置普遍缺點(diǎn)是儀器和編碼器慣性經(jīng)常限制了響應(yīng)速度，從而也限制了工作頻率。[6]Indesigningsuchsystem,considerationmustbegiventothecomputertimerequiredtoaccessandprocessthetransduceroutputdata.在設(shè)計這類系統(tǒng)時，必須考慮到存取和處理傳感器輸出數(shù)據(jù)所需要計算機(jī)時間。第25頁16.4UseofSensorinProgrammableAutomationUnit16TransducersInthissectionweareconcernedwiththeapplicationofsensor-mediatedprogrammableautomationtomaterial-handling,inspection,andassembleoperationsinbatch-produced,discrete-partmanufacturing.這部分介紹以傳感器為媒介可編程自動化在批量生產(chǎn)和分散零部件制造時材料搬運(yùn)，檢測和裝配工序上應(yīng)用。第26頁16.4UseofSensorinProgrammableAutomationUnit16TransducersProgrammableautomationconsistsofasystemofmulti-degree-of-freedommanipulators(commonlyknownasindustrialrobots)andsensorsundercomputercontrol,whichcanbeprogrammedtoperformspecifiedjobsinthemanufacturingprocessandcanbeappliedtonew(butsimilar)jobsbyreprogramming.可編程自動化裝置是由計算機(jī)控制多自由度機(jī)械手（通常稱為工業(yè)機(jī)器人）和傳感器組成系統(tǒng)，它能夠經(jīng)過編程完成加工過程中特定加工任務(wù)，并能重新編程以適應(yīng)新（類似）加工任