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Inrecentyears,withtheprogressofsocietyandthecontinuousexpansionofrailway,unmannedrailwaymouthincreasinglyarousedpeople'sconcern.Usingunmannedrailwaymouth,notonlycangreatlysavemanpower,materialandfinancialresourcesconsumption,andcaneffectivelyreduceduetohumanerrorcausedtheaccident.Thispaperdesignedakindofwiththemicrocontrollersasthecontrolcenterofthedetectionsystembasedonvibrationsensor.Systemmainlyincludepowersupplycircuitmodule,MCUmodule,modeselectionmodule,motordrivemodule,vibrationsensormoduleandtrafficlightsandothercomponentsofthemodule,withmanual/automaticswitchingfunction.Themanualstate,thecontrolofthemotorbystaffarepositiveandnegativerotationcompleteguardrailriseandfall;Inautomaticstate,startedbyvibrationsensordetectiontothesignalcontrolsystem,thecompletionofthemotorispositiveandnegativerotationimplementationbarriersofriseandfall,atthesametimecooperatewithtrafficlightsonthehighwayandthebuzzeralarmdevice,controlorbanningofpedestriansandvehicles,thusensuringthedrivingsafety.Thesystemnotonlycanrealizeautomaticcontrolofunmannedrailwaycrossing,butalsoincaseofanemergencycanusemanualmodetocontrolthetrafficintersection,systemoperationissimple,easytouse,hasacertainpracticalvalue.Key Vibrationsensor MotordriveTheTheResearchWiththecontinuousdevelopmentofeconomicconstructioninourcountry,thetransportationhasthemoreprosperous,andrailwayisthenationalimportantinfrastructurefacilities,isoneoftheresourcesandenvironmentfriendlywayoftransportation,speeduptherailwaydevelopmenthas etheconsensusofthesocietyindifferentaspects.Theadvantageofrailtransport:security,economic,convenient,affordable,all-transportation,andfastspeed,largecapacity,safeandcomfortable,energy-savingandground-saving,reductionefficiency,etc.Asthearteryofnationaleconomy,thedevelopmentofrailwayhasasignificantroleandfar-reachinginfluenceinourcountry'seconomicandsocialdevelopment.Therefore,ourcountryisdevelotheconstructionoftherailwayindustrycareer.Butfornowthetrainintherailwaycrossingprotection,thegenerallightandfenceareartificialcontrolwork,hardtoavoiderrors,andrailwaycrossingisvarious,manpowerandmaterialresourcesandfinancialresourcesusedupbig,railwaycrossinghasbeenthefocusoftherailwaytransportationsafetyproblemsandweakness.Therefore,somedevelopedcountriesabroadtherailwaycrossingcontrolstudiesfocusonsignalcontrol,butthecontroleffectisnotControlmethodofrailwaycrossingtoroughlythefollowingtwoways:someguardsandunmanned.Manualcontrolmodeiscrossinggatemachineorgatebymanualmanipulation.Manualcontrolandlocalcontrolandelectricremotecontroltwokinds.①Localcontrol:Thekeeperhadreceivedaphonecalloratrainapproachingautomaticnotification,closethegateintime,atthesametimewithsounderandflashcrossingsignalalarmtoroadvehiclesandpedestrians;Immediayaftertrainthroughopenbarwoodmachine.②Electricremotecontrol:Nearbythestationfloorattendantorsignalremotecontrolelectricgate,andbysettingthestateofthemonitorsurveillancecrossinggate.Withelectricfieldwoodmachine,severaladjacentcrossingcanbemadeofaunifiedcontrol.Automaticcontrolmodeisautomaticallybythecrossingsignalandautomaticbarwoodfinishcrossingprotection.Closetothetraincrossingthroughthetrackcircuitorothersensorswillbeclosetotransmittheinformationinatimelymannertothecrossing,crossingsignalandsounderflashinglightsandsoundsignalautomatically,automaticgatemachine.ThecurrentlargenumberofrailwaycrossingisdevelotowardsthedirectionofunattendedIsraelreubenites,car,theroadthreerelationscoordination.Withthedevelopmentofrailwaytransportationeconomy,thecontinuousexpansionofrailway,unmannedrailwaymouthismoreandmorearousedpeople'sconcern.Railwaycrossingnotwatchedassavemanpower,financialresourcesandagreatsolutiontoreduceaccidents,therefore,therearemanydesigntheauthordesignedforunattendedrailwaycrossingmanysolutions,thiscircuitisalsoconductedonthebasisoftheimprovedbasedonthepredecessors'design.TheResearchDesignDesignbackground:Unmannedrailwaycrossing.Theinstallationsite:Railwaycrossing.Realizethefunction:Theriseandfalloftheriseandfallofartificialrailingsandmodesofautomaticrailingandsoundandlightalarm,etc.becauseoxidativeagingcausedbythefault;Workingcircuitisnormalandregulartestingvibrationresponseincaseinsensitiveerrorinrailwaycrossing.SubjectRailwaycrossinginthedevelopmentoftheautomaticcontrolsystemofresearch,aimedatresolvingthehumantrafficduetotheincreasingdemandforheavysecurityproblemincreasingly,confinedtotrafficandroadconstructionofthetemporaryshortageofrapidgrowth,makemorevehiclesafetyandefficientuseofroadresources,avoidtheunattendedorman-madecausessuchasunnecessarysecuritycasualties.Railnetworkistheartery,asymbolofacountry'slevelofindustrialcivilization.Trafficrelationswithpeoplefortheproperty,safetyandtheinterestsofthetime.Withexcellentscientifictrafficcontroltechnologyforthesecurityofthelogisticsresourcesisveryvaluable,toensurethesafetyoftrafficlinessmooth,toensurethattravelatease,logisticsontimeinplaceorevenanextensionoftheroadoflife.ThissystemadoptstheMSC-51seriesmicrocontrollerATSC51andprogrammablevibrationsensordevicestodesigntheautomaticcontrolofunmannedrailwaycrossing,unattendedrailwaycrossingofmanualandautomaticProjectInmanualmode,staffcontrolofguardrailofrisingandfallingbythemotor’spositiveandnegativerotation.Inautomaticstate,whenatleast2minutesbeforethetrainthroughthefork,accordingtothevibrationsensordetectionsignallaunchcontrolsystem,completetheredlightonthehighway,alarmbellsringing,andloweredtheguardrail,banpedestriansandmotorvehicles;Whenthetrainleavesatleast30secondsaftertheguardrail,highwaygreenlight,pedestriansandmotorvehicles.Requestaccesstorelevantinformationforschemecomparison,determinethedesignschemeandaccordingtothesetrequiredforeachcomponenttypeandparameters.ResearchWiththecontinuousdevelopmentofeconomicconstructioninourcountry,thetransportationhas,themoreprosperous,andrailwayisthenationalimportantinfrastructure,thearteryofnationaleconomy,thebackboneofthetransportationsystem,forthenormaloperationofthecountry'ssocialeconomyanddevelopmentplaysadecisiveroleandthefunctionoftheoverallsituation.Thetransportationofrailwaytransportcapacitybig,canaffordalargeamountofpassengerandcargotransportationtask,highspeed,smallrestrictedbyclimateconditions,canbeall-weatheroperationsandlowertransportationcosts.Therefore,ourcountryisdevelotheconstructionoftherailwayindustrycareer.Butfornowthetrainintherailwaycrossingprotection,thegenerallightandfenceareartificialcontrolwork,hardtoavoidhaserrors,andrailwaycrossingisvarious,manpowerandmaterialresourcesandfinancialresourcesconsumption.Andautomaticcontrolsystemisverygoodtosolvetheproblem.Unattendedrailwaycrossingtominimizethecasualtiesofrailroadcrossing,improveintersectioncapacityandsavemoremanpower.Thissystemispractical,simpleoperation,strongextension,moreTheSystemHardwareCircuitTheTotalPrincipleBlockUnattendedrailwaycrossingtheautomaticcontrolsystemismainlycomposedofpowersupplycircuit,modeselectioncircuit,soundandlightalarmcircuit,motordrivecircuit,vibrationsensordetectioncircuitandsinglechip puterminimumsystemcircuitmodule,etc.Figure2.1Basedonsinglechip puterautomaticcontrolsystemfortherailwaycrossingstructurediagramAsshowninfigure2.1,thedesignisbasedonsinglechip puterautomaticcontrolsystem,motorcontrolpartis220vacservomotor,relaycontroladoptsrelayishighvoltageandlowvoltagecontrolforsinglechip puterinherit220Vmotor.Sensormoduleisvibrationsensor,thisdesignUSESavibrationswitchSW-420,thevibrationofSW-420willbeclosed,afteraoperationalamplifier,formacomparisoncircuit,toproduceahighlevel,willproducealowlevelwhenclosed.SCMwillbedonebycollectingthesignalcontrol,atthesametimewhenvibrationstowarninglightsflashingbackandforth,atthesametimeabuzzerEachpartofcircuitPowersupplyThepowerrequiredforthissystem:voltage:5V.ThevoltagerequiredbythesystemcanselectvoltagestabilizingcircuitregulatortubeforLM7805,theoutputvoltageofregulatoris5V,theinputvoltageofregulatortubeistobegreaterthan8V,sothechoiceof9Vpowersupplytransformer.Currentis1333mA,2Wtransformercansatisfythesystemrequirements,consideringthetransformercostandvolume,thesystemchoose5Vpowersupplytransformer.Theothercircuitcomponentsareclassicvalue.Figure2.2DCpowersupplycircuitThepowersupplycircuitwiringdiagramasshowninfigure2.3.Circuitisregulatedpowersupplyfortheoutputvoltage+5V、theoutputcurrent1.5A.Itiscomposedofpowertransformers,bridgerectifiercircuitD14~D17,filtercapacitorC11,C13,preventself-excitedcapacitanceC12,C13andastationarythree-terminalvoltageregulator(7805)isverysimpleandeasily.220VDCistransformedintothelowDCbylowvoltagepowertransformer,thenthroughbridgerectifiercircuitD1~D4andfiltercapacitorC11rectifierandfilter,thestationarythree-terminalvoltageregulatorLM7805Vin&GNDformedatbothendsofaDCvoltageisnotverystable(Thevoltageisoftenchangingbecauseofthemainsvoltagefluctuationloadchangesandotherreasons。TheDCvoltageproducehighprecision,goodstabilityDCoutputvoltageintheoutputofthestabilizedvoltagesupply,thoughLM7805onvoltagestabilityandC13filter.TheregulatedpowersupplycanbeusedasaMCUcircuitofpowersupply. PowercircuitwiringMCUSTC89C52MCUSTC89C52isonSTCcompanyproductionofalowpowerconsumption,highperformanceCMOS8bytemicrocontroller,with8KsystemprogrammableFlashmemory.STC89C52isusedclassicalMCS-51kernel,butmadealotofimprovementsthattraditionaldoesnotthefunctionofthe51single-chip puterchip.Onasinglechip,ithasthenimble8bitCPUandsystemprogrammableFlash,makeSTC89C52providehighflexibleandeffectivesolutionformanyembeddedcontrolsystems.Therearethefollowingstandardfunctions:8kbyteFlash,512bytesRAM,32byteI/Oportline,thewatchdogtimer,thebuilt-inblock4KBEEPROM,MAX810resetcircuit,three16-bittimer/counter,4externalinterrupt,a7vector4levelinterruptstructure(compatiblewithtraditional51MCU5vectorlevel2interruptstructure),fullduplexserialport.AnotherSTC89C52canbereducedto0Hzstaticlogicoperation,supporttwokindsofsoftware,canchoosepowersavingmode.Ontheidlemode,theCPUstopworkingandallowtheRAM,timer/counter,aserialportcontinuetowork.Onthepower-failprotectionmode,thecontentofRAMaresaved,theoscillatorisfrozen,theMCUstopallwork,untilthenextinterruptorhardwarereset.Itshighestoperatingfrequencyis35MHz,canchoose6T/12T.STC89C52RMCUworkingmodeypicalconumption<01μAPowrbyexternalinterrupt,interruptreturn,continuetoimplementtheprogram;Idlemode:TypicalpowerconsumptionNormalworkingmode:TypicalpowerconsumptionPowerdownmodecanbeawakenedbyexternalinterrupt,isSuitableforwatermeter,gasmeterandotherbatterypowersupplysystemandotherportabledevices.Figure Single puterminimumCrystalResonanceCircuitAndResetFigure2.5CrystalresonanceCrystalsisshortforquartzoscillator,EnglishnamedCrystal,Crystalvibrationcanbedividedintopassiveandactivecrystals,itsactionisoscillatingcurrentinacircuit,theclocksignal.Itisthemostimportantpartsintheclockcircuit,itsfunctionistoprovideICandothercomponentsreferencefrequency,it'slikeastick,workingfrequencyinstabilitywillcausetherelatedequipmentworkingfrequencyisnotstable,easytoproblems.Now,thanksto temperaturestability.Resetcircuitisanintegralpartthatistoensurethecircuitof putersystembeingstableandreliablework,thefirstfunctionofresetcircuitispoweronreset.Generally,putercircuitworknormallyneedpowersupplyfor5V±5%,namelyfrom4.75V5.25V.The puterissequentialcircuitdigitalcircuit,itneedsastableclocksignal,therefore,whenpoweron,onlywhenVCCismorethan4.75Vbelow5.25Vandcrystaloscillatorstabilitywork,resetsignalisremoved,the putercircuitbegantoworkproperly.Sofar,thesingle-chip puterresetcircuitmainlyhastwotypes:oneistheelectricreset,theotherismanuallyreset.Theprincipleoftheresetasshowninfigure2.6.Figure puterresetOntheprincipleofelectricreset:WhenVCCistoelectricity,C16ischarging,the10Kresistorappearonvoltage,theMCUisreset;Afewmillisecondslater,C16isfilled,currentof10kresistoriszero,soisvoltage,MCUisintotheworkingstate.Manualresetprinciple:Duringthework,pressSW4,C16discharge.letSW4go,C16charging,the10Kresistorappearonvoltage,theMCUisreset.Afewmillisecondslater,MCUisintotheworkingstate.Thecircuitdesignisverysimple,youcanachieveasimplepromptandalarmfunction.MCUexportsaswitchsignaltothetransistor,triggeringtransistortoachievethisfunction.Figure ModeSelectionFigure2.8ModeselectionAsshowninFigure2.8,thedesignofcircuitmainlydesignfourbuttons,oneofthemS6keyismodetogglebutton,whenS6ispressed,thesystemwillswitchbetweenautomaticmodeandmanualmode,andentereachmode,achievetheirfunctions.Inmode,whentheS7keyispressed,thestepmotoristurning,whentheS8keypress,thestepmotorreverserotation,inordertorealizethemanualmodebythesteppermotortodrivetheguardrailrisesandlanding.TheS9keyisexitmode.Inautomaticmode,thebuttonhasnoeffect.TheTrafficLightFigure2.9ThetrafficlightWhenthevibrationsensordetectioncircuittohavevibration,thesystemwillgenerateinterrupts,intotheinterruptsubroutine,andP1mouthcycleforlowlevelMCUsystem,lightcircuitsimulationtrafficlightcycle.MotorDriveFigure2.10MotordriveThissystemusesafourphasefivelineofsteppermotor.AsaresultoftheMCUoutputcurrentissmall,itcan'tdirectlydrivesteppermotor,shouldpassthedrive,ordriverchip,ordrivecircuitbydiscretecomponents.SowhatthistopicusedisthelargecurrentcompositetransistorULN2003.Steppermotortransformstheelectricalpulsesignalintoangulardisplacementorlineardisplacementofopenloopcontrolstepmotor.Inthecaseofthenotoverload,motorspeed,stoppositiononlydependsonthepulsesignalfrequencyandpulsenumber,andnotaffectedbyloadchange.whenthestepperdriverreceivesapulsesignal,itisdrivingasteppermotoraccordingtosetthedirectionofafixedAngle,knownasthe"stepAngle",itsrotationisbasedontheAngleofthefixedstepbystepCanbecontrolledbycontrollingthepulsenumberofangulardisplacement,soastoachievethepurposeofaccuratepositioning;Aswellasbycontrollingthepulsefrequencytocontrolmotorrotationspeedandacceleration,soastoachievethepurposeofregulating.Figure2.11VibrationsensorThesensorsisveryimportantinthesystem,thetheoreticalvalidation,thecomparisonandtestformanytimes,haschosentheTsinghuaUniversityInstituteofPrecisioninstrumentMLY-9200seriesvibrationsensor,itcanbeusedtomeasurethebearingseat,casingorvibrationofthestructure.Theoutputvoltageisproportionaltothevibrationvelocity,thereforeisalsocalledthespeedsensor.Thevibrationsensorusingtheturtleinductionprincipleconvertvibrationsignalsintoelectricalsignals,itmainlyincludemagneticcircuitsystem,inertialmass,springdam,etc.Wheninstallation,tightenitattheinnersideofthetracks,trackvibration,withintheworkingfrequencyrangesensor,thesensordorelativemovementofthecoilandmagnet,cuttinglines,toproduceinducedvoltageinthecoil,thevoltageisproportionaltothevibrationvelocity.Fieldtestshowsthatthesensorcanmeettherequirements,totravelwithin1kmofthetraincanbedetected.Ithasthefollowingfeatures:Signalandthevibrationvelocityisproportionaltothe,suitablefor5~1000frequencyrange,suitableforrailwaytrackvibrationinlowfrequencyrange(500Havealowoutputimpedance,goodsignal-to-noiseratio,easytoSensorsiscancelledwiththeactivitiesofthefrictionelement,sogoodflexibility,canmeasuresmallvibrationdisplacement,havecertainabilityoftransversevibration.Thesystemindifferentdistanceandroadexperimentmanytimes,andartificialrecorddatacomparison,asshownintable2-3. Dataactualtrainup/downnumbersystemwarningup/downnumberTheactualdistanceDisplayrangeerror/mAlertsFromthetable2-3contentshowsthatthesystemcanaccurayforecastwithin1kmofTDDtrainhas,accordingtotheerroriswithin+100m,canhaveaccurateearlywarningrole.Afterlookinguptheseliteratures,accordingtotheirownactualsituation,thissystemchosetouseSW420oftenclosedvibrationswitch.Whenthesystemisinautomaticmode,switchingtoavibration,fiveseconds,electricopportunitytoreverse,audibleandvisualalarmatthesametimeAfterfiveseconds,electricityforward,atthesametimereporttothe.Althoughnotveryaccuratetocompletethetaskofthebookupto2kmawaytoachievethefunctionrequirements,butthistopicisbasedonthebasisoftheselected,probablyontheimplementationandthesubjectofsimilarfunction,havecertainresearchsignificance.NormallyclosedtypevibratorSW–Usedtotriggertheeffectofvariousvibration,reportedthetheftalarm,inligentcar,earthquakealarm,motorcyclealarm,etc.Thismoduleiscomparedwiththenormallyopentypevibrationsensormodule,vibrationtriggerforlongerperiodsoftime,candrivetherelaymoduleThemoduleSensormodule,vibrationtriggerforlongerperiodsoftime,candrivetherelayTheSW-420normallyclosedtypevibrationThecomparatoroutput,signalclean,goodwaveform,drivingabilityisstrong,formorethan15mA.Theworkingvoltageo3.3VtoTheoutputform:digitalswitchoutput(0andAfixedbolthole,convenientSmallboardPCBsize:3.2cmx1.4UsetheLM393widevoltage NormallyclosedtypevibrationsensorModuleProductsdonotshock,vibrationswitchisclosedonstate,outputoutputlowlevel,thegreenlightislit;Productvibration,thevibrationswitchinstantaneousdisconnection,output,outputgreenlightisnotOutputcanbeattacheddirectlytothesinglechip puter,throughsinglechipputertodetectthehighandlowlevel,thustodetectifthereisavibrationenvironment,reporttotheTheSoftwareTheMainProgramFlowInitializetheInitializetheDetectionvibrationIfithasWaitfor5reverse90BuzzerSteppermotoris90waitfor5secondsLEDcontrollightswentoutClosetheInthedebuggingofhardwarecircuit,thefirstdebuggingisbatterychargingmodule,mainadjustingsliding,maketheoutputvoltageandthesaturationvoltage,batteryis6.5V。Thenextstepisthesensormoduleanddebugmodeselectionmodulethefirstismanualmode,thecontrolmotorispositiveandnegativerotationcompletedbystaffguardrailrisesandlanding.Intheautomaticstate,thesignalcontrolsystem,vibrationsensorstorisingpositiveandnegativerotationrealizestheguardrailandlanding。Inthedebugtrafficsignallamppowersupplymodulefoundnovoltageoutput,lookingforreasons,foundthatthepolarityofthediodeweldingerrorinthismodule.DesignThissystemisbasedonsinglechip puterautomaticcontrolsystem,thevibrationsensormoduletestinginputsignal,withmechanicaldevicestorealizeautomaticcontrolofrailwaycrossing.Thepresentresearchsituationanddevelopmenttrendathomeandabroadareyzedindetail,andcomparedtheoriginalstudyplan,choosetheautomaticcontrolsystemwiththesinglechipprocessorasthecore.Choosesinglechip puter,throughcomparingtheSW-420asthevibrationsensormodule,iftheSW-420closed,afteranoperationalamplifier,canformacomparisoncircuit,ahighlevel,whereaslowlevel,singlechip puterthroughgatheringtheinterruptsignaltorealizetheautomaticcontrolofthesystem.Principlediagramofsystemandthedrawingofpartsfigure,accordingtothecircuitcircuitelementtothedesignofthepartsweldedonthecircuitboard.Combinedhardwareandsoftwaretodebugthecircuit.Duetothedemandishigher,theimplementationofthissystemandresearchtime,andmyabilityislimited,sotherearemanyneedimprovements.[1].铁路道口事故分析与预测[J].东学[2].无人管理道口的自动控制[J].铁路通信信号设计[3]等.列车接近无人看守道口的无线预报装置[J].铁道与经济[4].无人看守铁路道口自动装置设计[J].铁路安全卫生与环保[5]张铁壁.一种火车接近无线系统的设计[J].河北工程技术高等专科学校学[6].列车接近无线系统的研制[J].青岛大学学报(自然科学版[7].一种多功能铁路道口系统[J].自动化技术与应用[8].一种道口系统的设计[J].工矿自动化[9],,王者堂,,珂.微机联锁控制的铁路道口系统设计与应用[J]..区间信号自动控制[12]FredColemanIII,YoungJ.Moon(2011)TrappedVehicleDetectionSystemforFourQuadrantGatesinHighSpeedRailCorridors,TransportationResearchRecord1648摘效减少由于人为造成的事故的发生。装置,控制行人及机动车的通行或,从
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