测控技术与仪器专业毕业设计外文翻译.docx

测控技术与仪器专业毕业设计外文翻译.docx

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测控技术与仪器专业毕业设计外文翻译

测控技术与仪器专业毕业设计外文翻译

DevelopmentofSensorNewTechnology

Sensorisonekindcomponentwhichcantransformthephysicalquantity,

chemistryquantityandthebiomassintoelectricalsignal.Theoutputsignal

hasthedifferentformslikethevoltage,theelectriccurrent,thefrequency,the

pulseandsoon,whichcansatisfythesignaltransmission,processing,

recording,anddemonstrationandcontroldemands.Soitistheautomatic

detectionsystemandintheautomaticcontrolindustry.Ifautomatic

Technologyisusedwider,thensensorismoreimportant.

Severalkeywordsofthesensor:

1SensorElements

Althoughthereareexception,mostsensorconsistofasensingelementanda

conversionorcontrolelement.Forexample,diaphragms,bellows,straintubesand

rings,bourdontubes,andcantileversaresensingelementswhichrespondtochanges

inpressureorforceandconvertthesephysicalquantitiesintoadisplacement.This

displacementmaythenbeusedtochangeanelectricalparametersuchasvoltage,

resistance,capacitance,orinductance.Suchcombinationofmechanicalandelectrical

elementsformelectromechanicaltransducingdevicesorsensor.Similarcombination

canbemadeforotherenergyinputsuchasthermal.Photo,magneticand

chemical,givingthermoelectric,photoelectric,electromaanetic,andelectrochemical

sensorrespectively.

2SensorSensitivity

Therelationshipbetweenthemeasuredandthesensoroutputsignalisusually

obtainedbycalibrationtestsandisreferredtoasthesensorsensitivityK1=output-

signalincrement/measuredincrement.Inpractice,thesensorsensitivityisusually

known,and,bymeasuringtheoutputsignal,theinputquantityisdeterminedfrominput=output-signalincrement/K1.

3CharacteristicsofanIdealSensor

Thehighsensorshouldexhibitthefollowingcharacteristics.

（a）highfidelity-thesensoroutputwaveformshapebeafaithfulreproductionofthe

measured;thereshouldbeminimumdistortion.

（b）Thereshouldbeminimuminterferencewiththequantitybeingmeasured;the

presenceofthesensorshouldnotalterthemeasuredinanyway.

（c）Size.Thesensormustbecapableofbeingplacedexactlywhereitisneeded.

文献（d）Thereshouldbealinearrelationshipbetweenthemeasuredandthesensorsignal.

（e）Thesensorshouldhaveminimumsensitivitytoexternaleffects,pressuresensor,for

example,areoftensubjectedtoexternaleffectssuchvibrationandtemperature.

（f）Thenaturalfrequencyofthesensorshouldbewellseparatedfromthefrequency

andharmonicsofthemeasurand.

Sensorscanbedividedintothefollowingcategories:

1ElectricalSensor

Electricalsensorexhibitmanyoftheidealcharacteristics.Inadditiontheyoffer

highsensitivityaswellaspromotingthepossibleofremoteindicationor

mesdurement.

Electricalsensorcanbedividedintotwodistinctgroups:

（a）variable-control-parametertypes,whichinclude:

（i）resistance

（ii）capacitance

（iii）inductance

（iv）mutual-inductancetypes

Thesesensorallrelyonexternalexcitationvoltagefortheiroperation.

（b）self-generatingtypes,whichinclude

（i）electromagnetic

（ii）thermoelectric

（iii）photoemissive

（iv）piezo-electrictypes

Theseallthemselvesproduceanoutputvoltageinresponsetothemeasurandinputandtheireffectsarereversible.Forexample,apiezo-electricsensornormallyproducesanoutputvoltageinresponsetothedeformationofacrystallinematerial;however,ifanalternatingvoltageisappliedacrossthematerial,thesensorexhibitsthereversibleeffectbydeformingorvibratingatthefrequencyofthealternatingvoltage.

2ResistanceSensor

Resistancesensormaybedividedintotwogroups,asfollows:

（i）Thosewhichexperiencealargeresistancechange,measuredbyusingpotential-

dividermethods.Potentiometersareinthisgroup.

（ii）Thosewhichexperienceasmallresistancechange,measuredbybridge-circuit

methods.Examplesofthisgroupincludestraingaugesandresistancethermometers.

文献3CapacitiveSensor

Thecapacitancecanthusmadetovarybychangingeithertherelativepermittivity,theeffectivearea,orthedistanceseparatingtheplates.Thecharacteristiccurvesindicatethatvariationsofareaandrelativepermittivitygivealinearrelationshiponly

overasmallrangeofspacings.Thusthesensitivityishighforsmallvaluesofd.Unlikethepotentionmeter,thevariable-distancecapacitivesensorhasaninfinite

resolutionmakingitmostsuitableformeasuringsmallincrementsofdisplacementor

quantitieswhichmaybechangedtoproduceadisplacement.

4InductiveSensor

Theinductancecanthusbemadetovarybychangingthereluctanceoftheinductivecircuit.

Measuringtechniquesusedwithcapacitiveandinductivesensor:

（a）A.C.excitedbridgesusingdifferentialcapacitorsinductors.（b）A.C.potentiometercircuitsfordynamicmeasurements.

（c）D.C.circuitstogiveavoltageproportionaltovelocityforacapacitor.（d）Frequency-modulationmethods,wherethechangeofCorLvariesthefrequencyofanoscillationcircuit.

Importantfeaturesofcapacitiveandinductivesensorareasfollows:

（i）resolutioninfinite

（ii）accuracy?

0.1%offullscaleisquoted

（iii）displacementranges25*10-6mto10-3m

（iv）risetimelessthan50uspossible

Typicalmeasurandsaredisplacement,pressure,vibration,sound,andliquidlevel.5LinearVariable-differentialTtransformer

6Piezo-electricSensor

7ElectromagneticSensor

8ThermoelectricSensor

9PhotoelectricCells

10MechanicalSensorandSensingElements

Ininformationage,theinformationindustryincludesinformationgathering,transmission,processthreeparts,namelysensortechnology,communication,computertechnology.Becauseofultralargescaleintegratedcircuit’srapiddevelopmentafterhavingbeendevelopedModerncomputer

technologyandcommunication,notonlyrequestssensorprecisionreliability,

文献speedofresponseandgaininformationcontentrequestmoreandmorehighbutalsorequestsitscosttobeinexpensive.Theobvioustraditionalsensoriseliminatedgraduallybecauseofthefunction,thecharacteristic,thevolume,thecostandsoon.Asworlddevelopmanycountriesarespeedinguptothesensornewtechnology’sresearchandthedevelopment,andallhasobtained

theenormousbreakthrough.Nowthesensornewtechnologydevelopmentmainlyhasfollowingseveralaspects:

Usingthephysicalphenomenon,thechemicalreaction,thebiologicaleffectasthesensorprinciplethereforetheresearcheswhichdiscoveredthenewphenomenonandtheneweffectarethesensortechnologicalimprovingways.itisimportantstudiestodevelopednewsensor’sthefoundation.Japanese

SharpCorporationusesthesuperconductivitytechnologytodevelopsuccessfullythehightemperaturesuperconductivitymagneticsensorandgetthesensortechnologysignificantbreakthrough.Itssensitivityissohighandonlyinferiorinthesuperconductivityquantuminterferencecomponent.Its

manufacturecraftisfarsimplerthanthesuperconductivityquantuminterferencecomponent.Mayuseinmagnetismimageformationtechnology.Soithasthewidespreadpromotedvalue.

Usingtheimmunebodyandtheantigenmeetsoneanothercompoundwhentheelectrodesurface.Itcancausetheelectrodepotentialchangeandusethisphenomenontobepossibletogeneratetheimmunitysensor.Theimmunitysensormakeswiththiskindofimmunebodymaytosomeorganisminwhetherhasthiskindofantoriginalworkinspection.Likemayinspectsomebodywiththehepatitisvirusimmunebodywhethercontractsthehepatitis,playstoisfast,theaccuraterole.TheUSUCsixthbranchhasdevelopedthiskindofsensor.

Thesensormaterialistheimportantfoundationforsensortechnology,becausethematerialsscienceisprogressiveandthepeoplemaymakeeachkindofnewsensorForexamplemakingthetemperaturesensorwiththehighpolymerthinfilm;Theopticalfibercanmakethepressure,thecurrentcapacity,thetemperature,thedisplacementandsoonthemanykindsofsensors;Makingthepressuretransmitterwiththeceramics.Thehighpolymercanbecometheproportionadsorptionandthereleasehydrogenalongwiththeenvironmentrelativehumiditysize.Thehighpolymerelectricityliesbetween

文献theconstanttobesmall,thehydrogencanenhancethepolymerthecoefficientofdialecticalloss.Makingthecapacitorthehighpolymerdielectricmedium,determinestheelectriccapacitycapecitythechange,thenobtainstherelativehumidity.Makingtheplasmausingthisprincipletogatherthelegitimatepolystyrenefilmtemperaturesensorbelow,ithasthecharacteristic.

Measuredthewetscopeiswide;Thetemperaturerangeiswide,mayreach-400?

~+1,500?

;Thespeedofresponseisquick,issmallerthan1S;The

sizeissmall,mayuseinthesmallspacemeasuringwet;Thetemperaturecoefficientissmall.

Theceramicelectriccapacitytypepressuretransmitterisonekinddoesnothavetheintermediaryfluidthedrytypepressuretransmitter.Usestheadvancedceramictechnology,theheavyfilmelectronictechnology,itstechnicalperformanceisstable,theyeardriftingquantityissmallerthan0.1%F.S,warmfloatsissmallerthan?

0.15%/10K,anti-overloadsstrongly,

mayreachthemeasuringrangeseveralhundredtimes.Thesurveyscopemayfrom0to60mpa.GermanE+HCorporationandtheAmericanKahloCorporationproductisattheleadingposition.

Theopticalfiberapplicationissendthematerialsignificantbreakthrough,itsusesinmostearlytheopticalcommunicationtechniques.Intheopticalcommunicationusediscoveredworksasenvironmentalconditionchangeandsoonthetemperature,pres-sure,electricfield,magnet