摘要在空气介质中，超声测距传感器因其性能好，价格低廉、使用方便，在现场机器人定位系统、车辆自动导航、车辆安全行驶辅助系统、城市交通管理和高速公路管理监测系统，以及河道、油井和仓库及料位的探测中都有应用。由于超声波传播不易受干扰，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，如测距仪和物位测量仪等都可以通过超声波来实现。为此，深入研究超声波的产生与传播规律、开发高性能超声波换能器及其收发电路，对于超声波检测技术的发展具有十分重要的现实意义。本设计介绍了基于单片机控制的超声测距仪的原理：由AT89C51控制定时器产生超声波脉冲并计时，计算超声波自发射至接收的往返时间，从而得到实测距离。并且在数据处理中采用了温度补偿的调整，用四位LED数码管切换显示距离和温度。整个硬件电路由超声波发射电路、超声波接收电路、电源电路、显示电路等模块组成。各探头的信号经单片机综合分析处理，实现超声波测距仪的各种功能。在此基础上设计了系统的总体方案，最后通过硬件和软件实现了各个功能模块。相关部分附有硬件电路图、程序流程图，给出了系统构成、电路原理及程序设计。此系统具有易控制、工作可靠、测距准确度高、可读性强和流程清晰等优点。实现后的作品可用于需要测量距离参数的各种应用场合。关键词：AT89C51；超声波；测距；电路AbstractThefeaturesofthegoodperformance,lowcost，easyuseareinearnatedintheultrasonicdistancemeasurementsensor.Theultrasonicdistancemeasurementsensorisusuallyusedatthescenerobotpositioningsystem，automaticvehiclenavigation，thesafetyofvehiclestravelingsupportsystem，theurantrafficmanagementandthehighwaymanagementmonitoringsystem，aswellasthedetectinrivers，oilwells，storagesandmaterials.Theultrasonicwavetransmssionisnoteasytodisturb，itsenergyconsumptionisslowlyanditcanbetransmitteddistantlyinthemedium，soitisfrequentlyusedinultrasonicdistancemeasurement.Forexample，therangefinderandthemateriallevelfindercanbeaehievedbyultrasonicwave.Therefore，thein-depthstudyofthegenerationandtransmissionlawofultrasonicandthedevelopmentofhigh-performanceultrasonicsensorandtransmitandreceivecircuitsisofgreatpracticalsignificanceinthedevelopmentofultrasonicdetectiontechnology.ThedesignintroducestheprincipleoftheultrasonicdistancemeasurementinstrumentbasedonSCMC-controlled:AT89C51controlstimerstoproducetheultrasonicwavepulseandtime,countthetimeofultrasonicwavespontaneousemissiontoreceiveround-trip,thusobtainsthemeasureddistance.Andthetemperaturecompensationadjustmentisusedinthedataprocessing,withfourLEDnixietubesdisplaydistanceortemperaturebyswitching.Theentirehardwarecircuitiscomposedbyultrasonictransmittercircuit,ultrasonicreceivercircuit,thepowercircuit,displaycircuit,andothermodules.TheprobesignalsareintegratedanalysisedbySCMCtoachievethevariousfunctionsofultrasonicdistancemeasurementinstrument.Basedonthishasdesignedsystem'soverallconcept,finaladoptionofhardwareandsoftwaretoachievethevariousfunctionalmodules.Therelevantpartshavethehardwareschematicsandprocessflowchart.Ithasgiventhesystemconstitution,thecircuitryandtheprogramming.Theinstrumentsystemhasfeatures:easeofcontrol,stabilityofoperation,highnessofprecisionanddistinctnessofprogrammeprocess,etc.Aftertherealizationoftheworkscanbeusedforneedsofthevariousparametersmeasureddistanceapplications.Keywords:AT89C51;Ultrasonicwave;Measuredistance;circuit目录摘要.........................................................IAbstract........................................................II1绪论...........................................................11.1课...
