【本科优秀毕业设计】光电计数器的设计

光电计数器的设计摘要本系统采用的是以单片机STC89C52为核心的自动计数器。采用反射式光电传感器，将红外发光管与光电接收管相邻安放，每当物体通过一次，红外光就被物体反射，光电接收管接收一次，光电接收管的输出电压就发生一次变化，这个变化的电压信号通过放大和处理后，形成计数脉冲，通过光电隔离耦合并行输入至STC89C52单片机的P1口，通过软件控制和键盘设定计数值并用LED加以显示，便可实现对物体的计数统计。本计数器可将机械或人工计数方式变为电子计数，并且采用LED数码管显示，可适用于诸多行业，以满足现代生产、生活方式的需求。所谓的光电式传感器是将光信号转化为电信号的一种传感器。它的理论基础是光电效应。这类效应大致可分为三类。第一类是外光电效应，即在光照射下，能使电子逸出物体表面。利用这种效应所做成的器件有真空光电管、光电倍增管等。第二类是内光电效应，即在光线照射下，能使物质的电阻率改变。这类器件包括各类半导体光敏电阻。第三类是光生伏特效应，即在光线作用下，物体内产生电动势的现象，此电动势称为光生电动势。这类器件包括光电池、光电晶体管等。光电效应都是利用光电元件受光照后，电特性发生变化。敏感的光波长是在可见光附近，包括红外波长和紫外波长。市场上的光电计数器采用的光电传感器有摄像头、光电管等，采用的光的种类有普通光和激光，可见光和不可见光等。光电传感器一般由光源、光学通路和光电元件三部分组成。光电式传感器是以光电器件作为转换元件的传感器，光电检测方法具有精度高、应用快、非接触等优点，而可测参数多，光电传感器的结构简单，形式灵活多变因此，光电式传感器在检测和控制中应用非常广泛。【关键词】计数器光电传感器单片机数码管调研报告11当今生活是信息时代,是获取信息和处理信息,以及信息应用的时代传感信息与检测技术的重要性在于它是获得信息并对信息进行一定处理的基础技术,是获取信息和信息加工处理的重要手段之一。传感与检测技术是一门知识面广、综合程度高、实用性很强的专业课程。它从传感器的基本理论入手，着重讲叙传感器的结构与感测原理，传感器是一个二端口的装置，不同的传感器输入输出特性不同，同一传感器适应不同的被测信号呈现的特性也有所不同。尤其当被测信号为静态信号时两种状态下，传感器的输入输出特性完全不同。感测技术在许多新知识里都有应用，以信息的传感、转换、处理为核心，从基本物理概念入手，阐述热工量、机械量、几何量等参数的测量原理及方法。光电式传感器是将光信号转化为电信号的一种传感器。它的理论基础是光电效应。这类效应大致可分为三类。第一类是外光电效应，即在光照射下，能使电子逸出物体表面。利用这种效应所做成的器件有真空光电管、光电倍增管等。第二类是内光电效应，即在光线照射下，能使物质的电阻率改变。这类器件包括各类半导体光敏电阻。第三类是光生伏特效应，即在光线作用下，物体内产生电动势的现象，此电动势称为光生电动势。这类器件包括光电池、光电晶体管等。光电效应都是利用光电元件受光照后，电特性发生变化。敏感的光波长是在可见光附近，包括红外波长和紫外波长。数字式电子计数器有直观和计数精确的优点，目前已在各种行业中普遍使用。数字式电子计数器有多种计数触发方式，它是由实际使用条件和环境决定的。有采用机械方式的接触式触发的，有采用电子传感器的非接触式触发的，光电式传感器是其中之一，它是一种非接触式电子传感器。采用光电传感器制作的光电式电子计数器。这种计数器在工厂的生产流水线上作产品统计，有着其他计数器不可取代的优点。该例光电触发式电子计数器只有两位数，但通过级联可以扩展为四位，甚至多位。12光电计数的现状及发展前景随着科学技术的发展，电子计数器的辅助功能也逐渐增加，现在已经出现了多功能计数器，多功能计数器产品的响应度较高，交直、流电两用、耗能低、价格低、无机械碰撞、无磨损、使用寿命长，既可计数，又可计算。例如在毛衣编织机上运用，除可计数和计算外，还可实现断线报警。通用计数器不仅可测频率、周期还可以测多周期平均、时间间隔、频率比和累计等。频率计数器专门用于测量高频和微波频率的计数器。微波计数器是以通用计数器和频率计数器为主配以测频扩展器而组成的微波频率计。它的测频上限已进入毫米波段，有手动半自动、全自动3类。系列化微波计数器是电子计数器发展的一个重要方面。由于有光电计数的设计理念，因此有了光电计数的发展。在市场电子计数器行业需求增长有所减缓的现状下，产能扩张的势头并没有得到较好的控制。产能过剩、重复建设不仅导致生产与消费的失衡，而且还引发了电子计数器行业内的一系列恶性价格竞争，影响了电子计数器行业业的盈利能力。中国电子计数器行业市场现状，为外资企业入驻中国创造了条件，国际许多电子计数器行业企业已经看中在中国低成本拓展市场的机会，随着外资投入逐步加大，中国国内企业改革重组迅速加快。同时新的行业制度等政策的颁布和实施将促使我国电子计数器行业洗牌，企业兼并重组将在政策的促使下大力发展。由于当前电子计数器行业效益下滑，所以对电子计数器行业企业授信更要慎重。必须关注电子计数器行业子行业，关注电子计数器行业上下游企业，优化客户结构，针对电子计数器行业行业需求进行新产品开发。国内的制造技术水平远不如国外，制造技术不仅是衡量一个国家科技发展水平的重要标志,也是国际间科技竞争的重点。我国正处于经济发展的关键时期,制造技术是我们的薄弱环节。只有跟上发展先进制造技术的世界潮流,将其放在战略优先地位,并以足够的力度予以实施,才能尽快缩小与发达国家的差距,才能在激烈的市场竞争中立于不败之地。总之,在我国研究和发展先进制造技术势在必行。ENGLISHTRANSLATIONHISTORYABOUTELECTRONICSTHERECANBENODOUBTTHATTHE1900SISREMEMBEREDASTHEELECTRONICCENTURYOFCOURSETHEREHAVEBEENOTHERGREATADVANCESINTRANSPORTINSCIENCEINCOMMERCEANDMANYOTHERFIELDSBUTWHEREWOULDTHEYHAVEBEENWITHOUTTHEINSTRUMENTSANDDEVICESTHATELECTRONICSHASPROVIDEDHOWWOULDSEEA3DVIRTUALREALITYIMAGEOFYOURBEATINGHEATWITHNOELECTRONICSHOWWOULDYOUGETMONEYOUTOFTHEBANKONASUNDAYNIGHTWITHOUTELECTRONICSWOULDYOUGOTOAPOPCONCERTTHATHADNOAMPLIFIERSLARGESCREENSORLIGHTINGEFFECTSDONOTSAYYOUWOULDRATHERWATCHTVTHEREWOULDNOTBEANYELECTRONICSINTHEEARLY20THCENTURYSTARTEDTHRIVINGATAGREATERSPEEDUNLIKETHEPRE20THCENTURYDEVELOPMENTSTHERADIOINVENTEDBYTHEITALIANGENIUSMARCONIANDTHEWORKOFHENRYHERTZOPENEDTHEROADTOFURTHERDISCOVERIESANDINVENTIONSINTHEFIRSTDECADETHENEWTHINGTHATWASWELCOMEDTOTHETECHNICALWORLDWASTHEVACUUMTUBETHEVACUUMTUBESATTHATTIMEWORKEDASAMIRACULOUSCOMPONENTFORTHERADIODEVICESTHEREALELECTRONICSWHATITISCALLEDTODAYWASACTUALLYSTARTEDAFTERTHEDISCOVERYOFTHETRANSISTOREFFECTTRANSISTOROPENEDTHEROADFORTHEELECTRONICSANDMOREIMPORTANTLYITOPENEDTHEROADFORTHECOMPUTINGWORLDCOMPUTERSOFVARIOUSTYPESSTARTEDHITTINGTHEMARKETANDTHERESEARCHWORKSGOTABOOSTBECAUSEOFTHESTRONGPOINTOFULTRASONICENERGYCONSUMPTION,SLOW,MEDIUMOFCOMMUNICATIONINTHEDISTANCE,WHICHAREOFTENUSEDFORULTRASONICDISTANCEMEASUREMENT,SUCHASTHERANGEFINDERANDLEVELMEASUREMENTCANBEACHIEVEDBYULTRASOUNDUSEOFULTRASONICTESTINGISOFTENMORERAPID,CONVENIENT,SIMPLE,EASYTOACHIEVEREALTIMECONTROL,ANDMEASUREMENTACCURACYCANMEETTHEPRACTICALREQUIREMENTSOFINDUSTRY,INTHEMOBILEROBOTHASBEENDEVELOPEDONAWIDERANGEOFAPPLICATIONSTHESTRONGPOINTOFULTRASONICENERGYCONSUMPTION,SLOW,MEDIUMOFCOMMUNICATIONINTHEDISTANCE,SOIOFTENUSEULTRASONICTOMEASUREDISTANCE,SUCHASTHERANGEFINDERANDOBJECTMEASURINGINSTRUMENT,ULTRASONICRANGEFINDERDEVICEISPROVIDEDAIMINGPOINTDEVICE,ASLONGASTHEINSTRUMENTALIGNMENTOFTHEOBJECTTOBEMEASURED,THEREWILLBEAPOINTINTHERANGEFINDERDISPLAYSCREEN,MAINLYTHROUGHTHEVELOCITYMEASUREMENT,INVISIBLETOTHENAKEDEYEINJECTIONLINEULTRASONICRANGEFINDERFORTRANSMITTINGATTHESAMETIMETHEBEGINNINGOFTIME,THEULTRASONICTRANSMISSIONINTHEAIR,THEWAYTOMEETTHEOBSTACLEIMMEDIATELYRETURN,ULTRASONICRECEIVERRECEIVESTHEREFLECTEDWAVEISINTERRUPTEDIMMEDIATELYSTOPTHECLOCKTHROUGHCONTINUOUSDETECTIONOFGENERATEDWAVEEMISSIONOBSTACLEAFTERTHEECHOREFLECTED,INORDERTODETECTULTRASONICANDRECEIVESTHEECHOTTIMEDIFFERENCE,ANDTHENCALCULATEDTHEDISTANCELULTRASONICRANGEFINDER,BECAUSEULTRASOUNDISLARGELYINFLUENCEDBYTHESURROUNDINGENVIRONMENT,SOTHEGENERALMEASUREMENTWITHSHORTDISTANCE,LOWERMEASURINGACCURACYTHERANGEOFUSEISNOTVERYWIDE,BUTTHEPRICEISRELATIVELYLOW,GENERALLYAFEWHUNDREDYUANAPRINCIPLEOFULTRASONICDISTANCEMEASUREMENT1,THEPRINCIPLEOFPIEZOELECTRICULTRASONICGENERATORPIEZOELECTRICULTRASONIC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SSHOWAHIGHINONECYCLEANDALOWINTHENEXTCYCLE,THECOUNTISINCREMENTEDTHENEWCOUNTVALUEAPPEARSINTHEREGISTERDURINGS3P1OFTHECYCLEFOLLOWINGTHEONEINWHICHTHETRANSITIONWASDETECTEDSINCETWOMACHINECYCLES24OSCILLATORPERIODSAREREQUIREDTORECOGNIZEA1TO0TRANSITION,THEMAXIMUMCOUNTRATEIS1/24OFTHEOSCILLATORFREQUENCYTOENSURETHATAGIVENLEVELISSAMPLEDATLEASTONCEBEFOREITCHANGES,THELEVELSHOULDBEHELDFORATLEASTONEFULLMACHINECYCLEWITHTHERAPIDDEVELOPMENTOFSCIENCEANDTECHNOLOGY,THEULTRASONICRANGEFINDERINTHEMOREANDMOREWIDEAPPLICATIONBUTTHECURRENTTECHNICALLEVEL,PEOPLECANUSETHESPECIFICRANGEFINDERTECHNOLOGYEXTREMELYLIMITED,THEREFORE,THISISABOOMINGANDINFINITEPROSPECTOFTECHNICALANDINDUSTRIALAREASLOOKINGTOTHEFUTURE,ULTRASONICRANGEFINDERASANEWTYPEOFVERYIMPORTANTANDUSEFULTOOLINARESPECTTOHAVEVERYBIGDEVELOPMENTSPACE,ITWILLMOVETOWARDSAMOREHIGHPRECISIONPOSITIONINGINTHEDIRECTIONOFDEVELOPMENT,TOMEETTHEGROWINGNEEDSOFTHESOCIETY,SUCHASSONARBASICTRENDFORDEVELOPMENTMORESUITABLEFOROPERATIONINTHESHALLOWWATEROFSUBMARINESONAR,ESPECIALLYINSHALLOWSEATARGETRECOGNITIONPROBLEMTOLOWERTHESUBMARINESELFNOISE,IMPROVETHEWORKINGENVIRONMENTADMITOFNODOUBT,THEFUTUREOFTHEULTRASONICRANGEFINDERWITHAUTOMATIONANDINTELLIGENTCOMMUNITY,ANDOTHERRANGEFINDERSFUSION,FORMINGARANGEFINDERASTHERANGEFINDERTECHNOLOGYPROGRESS,RANGINGFROMSIMPLEJUDGMENTHASTHEFUNCTIONSTOTHEDEVELOPMENTHASTHELEARNINGFUNCTION,THEULTIMATEDEVELOPMENTOFCREATIVITYWITHTHEDEVELOPMENTOFSCIENCEANDTECHNOLOGY,THEIMPROVEMENTOFPEOPLESLIVINGSTANDARD,ACCELERATETHEDEVELOPMENTOFCITYCONSTRUCTION,CITYWATERSUPPLYANDDRAINAGESYSTEMHAVEGREATLYDEVELOPED,THESITUATIONCONTINUESTOIMPROVEHOWEVER,DUETOHISTORICALREASONSTHESYNTHESISTIMELIVEDMANYUNPREDICTABLEFACTORS,CITYWATERSUPPLYANDDRAINAGESYSTEMS,ESPECIALLYTHEDRAINAGESYSTEMOFTENLAGSBEHINDTHECITYCONSTRUCTIONTHEREFORE,OFTENAPPEARGOODBUILDINGEXCAVATIONHASBEENBUILDINGFACILITIESTOUPGRADETHEDRAINAGESYSTEMPHENOMENONTHEREFORE,DESIGNANDDEVELOPMENTOFBOXCULVERTDRAINAGEDREDGINGMOBILEROBOTAUTOMATICCONTROLSYSTEM,TOENSURETHEROBOTINTHEBOXCULVERTINFREEDRAINAGEDREDGINGCONTROLSYSTEMCOREPARTISTHERESEARCHANDDESIGNOFULTRASONICRANGEFINDERINTHENEWCENTURY,ANEWLOOKOFTHERANGEFINDERWILLPLAYABETTERROLE中文翻译电子技术历史毫无疑问的，20世纪是电子技术的世纪。当然许多其他行业如医药、交通、科学、商业、等也取得了很大的进步，但如果没有电子技术所提供的仪器和设备，这些行业能取得这么大的进步吗没有电子技术，你无法看到自己正在跳动的心脏的逼真的三维虚拟图像没有电子技术，你就无法在星期日的晚上从银行取钱。你愿意去参加一个没有音响放大器、没有大屏幕或灯光效果的流行音乐会吗不要说你宁愿在家看电视没有电子技术也就没有电视。与20世纪前不同，在20世纪早期，电子技术开始有了较快的发展。首先意大利天才马可尼发明的无线电和亨利赫兹的工作为电子技术进一步的发明创造开辟了道路。在20世纪第一个十年中最受技术世界欢迎的新东西是真空管，在那是真空管是无线电设备中的一个奇妙的器件。今天所说的电子技术实际上是在发现晶体管效应以后开始发展的。晶体管为电子技术开辟了道路，更重要的是它为计算机世界开辟了道路。各种类型的计算机开始在市场上出现，研究工作进入一个迅速发展的时代。由于超声波指向性强，能量消耗缓慢，在介质中传播的距离较远，因而超声波经常用于距离的测量，如测距仪和物理测量仪等都可以通过超声波来实现。利用超声波检测往往比较迅速、方便、计算简单、易于做到实时控制，并且在测量精度方面能达到工业实用的要求，因此在移动机器人研制上也得到了广泛的应用。超声波测距仪装置上有设置瞄点装置，只要把仪器对准要测量的目标，就会出现一点在测距仪的显示屏幕上，主要是通过声速来测量的，肉眼看不见射出的线。超声波测距仪在发射同时开始计时，超声波在空气中传播，途中碰到障碍物就立即返回来，超声波接收器收到反射波就立即中断停止计时。通过不断检测产生波发射后遇到障碍物所反射的回波，从而测出发射超声波和接收到回波的T时间差，然后求出距离L。超声波测距仪，由于超声波受周围环境影响较大，所以一般测量距离比较短，测量精度比较低。目前使用范围不是很广阔，但价格比较低，一般几百元左右。超声波测距原理1、压电式超声波发生器原理压电式超声波发生器实际上是0利用压电晶体的谐振来工作的。超声波发生器内部结构