外文文献加中文翻译-基于单片机的超声波测距系统的设计

ULTASONICRANGINGINAIRGERUDASHEVSKIANDAAGORBATOVUDC534,3219531710837ONEOFTHEMOSTIMPORTANTPROBLEMSININSTRUMENTATIONTECHNOLOGYISTHEREMOTE,CONTACTLESSMEASUREMENTOFDISTANCESINTHEORDEROF02TO10MINAIRSUCHAPROBLEMOCCURS,FORINSTANCE,WHENMEASURINGTHERELATIVETHREEDIMENSIONALPOSITIONOFSEPARATEMACHINEMEMBERSORSTRUCTURALUNITSINTERESTINGPOSSIBILITIESFORITSSOLUTIONAREOPENEDUPBYUTILIZINGULTRASONICVIBRATIONSASANINFORMATIONCARRIERTHEPHYSICALPROPERTIESOFAIR,INWHICHTHEMEASUREMENTSAREMADE,PERMITVIBRATIONSTOBEEMPLOYEDATFREQUENCIESUPTO500KHZFORDISTANCESUPTO05MBETWEENAMEMBERANDTHETRANSDUCER,ORUPTO60KHZWHENRANGINGONOBSTACLESLOCATEDATDISTANCESUPTO10MTHEPROBLEMOFMEASURINGDISTANCESINAIRISSOMEWHATDIFFERENTFROMOTHERPROBLEMSINTHEAPPLICATIONOFULTRASOUNDALTHOUGHTHEPOSSIBILITYOFUSINGACOUSTICRANGINGFORTHISPURPOSEHASBEENKNOWNFORALONGTIME,ANDATFIRSTGLANCEAPPEARSVERYSIMPLE,NEVERTHELESSATTHEPRESENTTIMETHEREAREONLYASMALLNUMBEROFDEVELOPMENTSUSINGTHISMETHODTHATARESUITABLEFORPRACTICALPURPOSESTHEMAINDIFFICULTYHEREISINPROVIDINGARELIABLEACOUSTICTHREEDIMENSIONALCONTACTWITHTHETESTOBJECTDURINGSEVERECHANGESINTHEAIRSCHARACTERISTICPRACTICALLYALLACOUSTICARRANGEMENTSPRESENTLYKNOWNFORCHECKINGDISTANCESUSEAMETHODOFMEASURINGTHEPROPAGATIONTIMEFORCERTAININFORMATIONSAMPLESFROMTHERADIATORTOTHEREFLECTINGMEMBERANDBACKTHEUNMODULATEDACOUSTICULTRASONICVIBRATIONSRADIATEDBYATRANSDUCERARENOTINTHEMSELVESASOURCEOFINFORMATIONINORDERTOTRANSMITSOMEINFORMATIONALCOMMUNICATIONTHATCANTHENBESELECTEDATTHERECEIVINGENDAFTERREFLECTIONFROMTHETESTMEMBER,THERADIATEDVIBRATIONSMUSTBEMODULATEDINTHISCASETHEULTRASONICVIBRATIONSARETHECARRIEROFTHEINFORMATIONWHICHLIESINTHEMODULATIONSIGNAL,IE,THEYARETHEMEANSFORESTABLISHINGTHESPATIALCONTACTBETWEENTHEMEASURINGINSTRUMENTANDTHEOBJECTBEINGMEASUREDTHISCONCLUSION,HOWEVER,DOESNOTMEANTHATTHEANALYSISANDSELECTIONOF241DLTGEPRADPARAMETERSFORTHECARRIERVIBRATIONSISOFMINORIMPORTANCEONTHECONTRARY,THEFREQUENCYOFTHECARRIERVIBRATIONSISLINKEDINAVERYCLOSEMANNERWITHTHECODINGMETHODFORTHEINFORMATIONALCOMMUNICATION,WITHTHEPASSBANDOFTHERECEIVINGANDRADIATINGELEMENTSINTHEAPPARATUS,WITHTHESPATIALCHARACTERISTICSOFTHEULTRASONICCOMMUNICATIONCHANNEL,ANDWITHTHEMEASURINGACCURACYLETUSDWELLONTHEQUESTIONSOFGENERALIMPORTANCEFORULTRASONICRANGINGINAIR,NAMELYONTHECHOICEOFACARRIERFREQUENCYANDTHEAMOUNTOFACOUSTICPOWERRECEIVEDANANALYSISSHOWSTHATWITHCONICALDIRECTIVITYDIAGRAMSFORTHERADIATORANDRECEIVER,ANDASSUMINGTHATTHEDISTANCEBETWEENRADIATORANDRECEIVERISSUBSTANTIALLYSMALLERTHANTHEDISTANCETOTHEOBSTACLE,THEAMOUNTOFACOUSTICPOWERARRIVINGATTHERECEIVINGAREAPRFORTHECASEOFREFLECTIONFROMANIDEALPLANESURFACELOCATEDATRIGHTANGLESTOTHEACOUSTICAXISOFTHETRANSDUCERCOMESTOWHEREPRADISTHEAMOUNTOFACOUSTICPOWERRADIATED,BISTHEABSORPTIONCOEFFICIENTFORAPLANEWAVEINTHEMEDIUM,LISTHEDISTANCEBETWEENTHEELECTROACOUSTICTRANSDUCERANDTHETESTMEMBER,DISTHEDIAMETEROFTHERADIATORRECEIVER,ASSUMINGTHEYAREEQUAL,ANDCISTHEANGLEOFTHEDIRECTIVITYDIAGRAMFORTHEELECTROACOUSTICTRANSDUCERINTHERADIATORSIN21DJWBOTHINEQ1ANDBELOW,THEABSORPTIONCOEFFICIENTISDEPENDENTONTHEAMPLITUDEANDNOTONTHEINTENSITYASINSOMEWORKS1,ANDTHEREFOREWETHINKITNECESSARYTOSTRESSTHISDIFFERENCEINTHEVARIOUSPROBLEMSOFSOUNDRANGINGONTHETESTMEMBERSOFMACHINESANDSTRUCTURES,THERELATIONSHIPBETWEENTHESIGNALATTENUATIONSDUETOTHEABSORPTIONOFAPLANEWAVEANDDUETOTHEGEOMETRICALPROPERTIESOFTHESOUNDBEAMARE,ASARULE,QUITEDIFFERENTITMUSTBEPOINTEDOUTTHATTHECHOICEOFTHEGEOMETRICALPARAMETERSFORTHEBEAMINSPECIFICPRACTICALCASESISDICTATEDBYTHESHAPEOFTHEREFLECTINGSURFACEANDITSSPATIALDISTORTIONRELATIVETOSOMEAVERAGEPOSITIONLETUSCONSIDERINMOREDETAILTHERELATIONSHIPBETWEENTHEGEOMETRICANDTHEPOWERPARAMETERSOFACOUSTICBEAMSFORTHEMOSTCOMMONCASESOFRANGINGONPLANEANDCYLINDRICALSTRUCTURALMEMBERSITISWELLKNOWNTHATTHEDIRECTIONALCHARACTERISTICWOFACIRCULARPISTONVIBRATINGINANINFINITEBAFFLEISAFUNCTIONOFTHERATIOOFTHEPISTONSDIAMETERTOTHEWAVELENGTHD/ASFOUNDFROMTHEFOLLOWINGEXPRESSION2WHEREJLISABESSELFUNCTIONOFTHEFIRSTORDERANDISTHEANGLEBETWEENANORMALTOTHEPISTONANDALINEPROJECTEDFROMTHECENTEROFTHEPISTONTOTHEPOINTOFOBSERVATIONRADIATIONFROMEQ2ITISREADILYFOUNDTHATATWOTOONEREDUCTIONINTHESENSITIVITYOFARADIATORWITHRESPECTTOSOUNDPRESSUREWILLOCCURATTHEANGLE（3）FORANGLES20EQ3CANBESIMPLIFIEDTO（4）D760RCSI50FDC7605WHERECISTHEVELOCITYOFSOUNDINTHEMEDIMAAANDFISTHEFREQUENCYOFTHERADIATEDVIBRATIONSITFOLLOWSFROMEQ4THATWHENRADIATINGINTOAIRWHEREC330M/SEC,THENECESSARYDIAMETEROFTHERADIATORFORASPEDFIEDANGLEOFTHEDIRECTIVITYDIAGRAMATTHE05LEVELOFPRESSURETAKENWITHRESPECTTOTHEAXISCANBEFOUNDTOBE（5）WHEREDISINCM,FISINKHZ,ANDISINDEGREESOFANGLECURVESARESHOWNINFIG1PLOTTEDFROMEQ5FORSIXANGLESOFARADIATORSDIRECTIVITYDIAGRAMTHEDIRECTIVITYDIAGRMNEEDEDFORARADIATORISDICTATEDBYTHEMAXIMUMDISTANCETOBEMEASUREDANDBYTHESPATIALDISPOSITIONOFTHETESTMEMBERRELATIVETOTHEOTHERSTRUCTURALMEMBERSINORDERTOAVOIDTHEINCIDENCEOFSIGNALSREFLECTEDFROMADJACENTMEMBERSONTOTHEACOUSTICRECEIVER,ITISNECESSARYTOPROVIDEASMALLANGLEOFDIVERGENCEFORTHESOUNDBEAMAND,ASFARASPOSSIBLE,ASMALLDIAMETERRADIATORTHESETWOREQUIREMENTSAREMUTUALLYINCONSISTENTSINCEFORAGIVENRADIATIONFREQUENCYAREDUCTIONOFTHEBEAMSDIVERGENCEANGLEREQUIRESANINCRE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SIN21DJW图3在声音的各种问题上，包括成员测试设备和结构的关系，由于信号衰减吸收的平面和适当的几何性质的声束是，作为一项规则，一定是相差甚远的需要指出的是，选择的实际情况中光束具体的几何参数，是基于形状的反射面和空间的一些失真相对平均排布。让我们考虑一下更详细的几何关系和声束的动力参数这个最常见包括平面和圆柱结构的成员情况。众所周知，定向特性瓦的一个圆形活塞振动无限挡板是一个活塞比例函数,D/为下列表达式基础（2）从均衡器（2）中很容易发现，在减少两到一个敏感性散热器方面,声压级角度将会引起注意。（3）表1F0KHZ102030405060801001502003005000DB/M05071215226354691640对角可以简化为20EQ（3）（4）其中C是中期声速,F是辐射震动的频率它遵循均衡器（4），当辐射到空中，其中C300米/秒，在05级的D760ARCSIN50FDC7605压力面，散热器为采取的轴的直径用于指定角度的方向性图上是必要的（5）其中D是厘米，KHZ是千赫，是度角。在图1中显示的曲线图是均衡器（5）中6个角度散热器的方向性图。事实上，直径的“超声波降解标本”现场控制的两个变量，即直径的散热器和发散角的声音束一般情况下，最小直径的“超声波降解标本”在现场飞机表面处理，通常倾向于散热器的轴心。（6）L是测试表面最小的距离。对应的散热器直径（7）（7）作为从均衡器（6）及（7），“声振”现场最小直径，最高要求散热器直径距离不得少于2自然的，以短距离的障碍的大小，“声振“表面的更少。其中D是厘米，KHZ的在千赫，是度角让我们考虑在半径为R的中声波测距的情况。问题是在X和Y中坐标轴上衡