安全气囊电子控制模块的开发分析

上海交通大学硕士学位论文安全气囊电子控制模块的开发分析姓名：李笑笑申请学位级别：硕士专业：电子与通信工程指导教师：李翔20070901DEVELOPMENTOFAIRBAGELECTRONICCONTROLUNIT,,,,,,ABSTRACTThispaperintroducesvehiclepassivesafetysystemfirstly.Manyforeigngovernmentandauto-makershavepaidhighattentiontovehiclesafetysystemlongyearsago,andmadeitsregulationorevenlawtoregulatethenewvehicleR&D,andgivescustomeraguidetodistinguishsafecarandunsafecar.Vehiclesafetysystemcanbedividedinto2parts,oneisactivesafetysystemandtheotherispassivesafetysystem.Activesafetysystemworksbeforecarcrash,tosomethingtopreventthecrashoraccident,whilepassivesafetysystemworksonceafteracarcrashoraccident,toeliminateorreducetheinjurytothepassengersinthecar.Passivesafetysystemcomprisesdeformableandenergy-absorbablecarcrashzone,reinforcedpassengercabinandpillar,seatbeltsystemandairbagsystem.AirbagECU(ElectronicControlUnit)isthecorepartofthepassivesafetysystem.Itmakethedecisionandcommandtheseatbeltandairbagtodeployornot.TheairbagECUdetectthevehiclemovementandifacarcrashoraccidentbeingdetected,theECUwilldoalgorithmtoseeifthecrashissevereenoughtodeploytheairbagorseatbelt.Ifyes,theECUwillsetignitioncurrenttofiretheairbagandseatbelt.TheECUiscapabletododiagnosticsofthewholesafetysystem.Whenanyerrorbeingdetected,theECwillstoretheerrorcodeandilluminatetheairbagwarningLEDtoinformthedriveraboutthefault.ThisarticlegivestheanalysisoftheairbagECUdevelopment.Relativetestdataandformhavebeincludedalsotoprovidebetterunderstandingofthedevelopment.Youcanalsofindthediagnosticsfunctionandfaultcodemanagementinthisarticle.Firingstrategyandalgorithmiskeytodiscriminateacrash.Thelastpartofthisdissertationprovidespersonalpointofviewandassumptionofwhatthesafetyelectronicssystemcouldbeorshouldbe,whatnewfeatureshouldbedevelopedintotheairbagECUinthefuture.KEYWORDS:ActiveSafetySystem,PassiveSafetySystem,FirstImpact,SecondImpact,Airbag,ECU,DSI20070920200792020079201.1953JornW.HertrickSRS(SupplementRestraintSystem)8050100045%60%(ActiveSafety)(PassiveSafety).,ABS211100%100%1115010001-1199720061-2199720060100,000200,000300,000400,000500,000600,000700,000800,000900,000Accidents305,000350,000410,000617,000760,003773,137667,507567,753450,254378,88119971998199920002001200220032004200520061-11997~2006Fig.1-1CountrywideTrafficAccidentStatistic(1997~2006)3020,00040,00060,00080,000100,000120,000DeathToll78,0082,0090,0094,00106,0109,3104,399,2198,7389,4419971998199920002001200220032004200520061-21997~2006Fig.1-2CountrywideTrafficAccidentDeathToll(1997~2006)45%60%(ActiveSafetySystem)(PassiveSafetySystem)112(ActiveSafetySystem)(PassiveSafetySystem).ABS,EBDASRESP4TRWABS113SRSECUSRSECU125GPSLIN,K-Line,CANFlexRay621ABC22(sensor)(ECU)(inflator)(bag)(clockspring)(airbagmodule)2-1Fig.2-1Inflator7221DABDriverAirbagPABPassengerAirbagSABSideAirbagCABCurtainAirbagTABThoraxAirbagKABKneeAirbag2-22-32-4AudiA62-2A6Fig.2-2AudiA6DAB2-3A62-4Fig.2-3AudiA6PABFig.2-4SAB822.2BagInflatorCover2-5Fig-2-5PABExplodedDrawing22.3N2232-6Fig.2-6AirbagECU924241197381519761219785019776FMVSS208FMVSSNHTSA2060ECEEEC200314166200620071242196731FMVSS20850ECE-R9456GB1155150FMVSS-21454GB-20071ECE-R9554FMVSS-208136895010243NCAP,NCAPNewCarAssessmentProgramUS-NCAPEuro-NCAP2006C-NCAP2-1NCAPNCAP100%40%C-NCAP50km/h56km/h50km/h+1NHTSA56km/h62km/h27°IIHS64km/h51km/hJ-NCAP55km/h64km/h55km/hE-NCAP64km/h50km/h2-1C-NCAPNCAPTable.2-1NCAPComparision113.1ECU3-13-1Fig.3-1AirbagSystemWorkingProcessECUECU3.2CPUEEPROMPowerSupplyEnergyReserveAccelerometerFiringUnitCommunicationInterfaceMultipleInterface3-2AirbagECU123-2ECUFig.3-2AirbagECUBlockDiagramA/DI/O/ECU3.2.13.2.1.1MY08ECUFreescaleX-Y3-313VssVssVss3-3MotorolaSX322Fig.3-3MotorolaAccelerometerSX322PIN#NAMEDESCRIPTIONInterface1VSSGNDGND2VSSGNDGND3VSSGNDGND4STSelf-testfromuPdigitalport(enable)5VOUTAccelerationoutputsignaltoA/D(microinput)6STATUSStatustouPinputport;monitorsensorstatus7VSSGNDGND8VDDPowerVcc;5V+/-5%9R/WRead/WriteforfactoryprogrammingUnconnected1410LOADLoaddataforfactoryprogrammingUnconnected11VPPHighprogrammingvoltagepinforfactoryprogrammingUnconnected12DATAUsedtoshiftdataintodeviceforfactoryprogrammingUnconnected13CLKCLKsignalusedforfactoryprogrammingUnconnected14N/CNoconnectNoconnect15N/CNoconnectNoconnect16N/CNoconnectNoconnect3-1SX322Table.3-1SX322PinDefinitionX-axis100Gg.VOutputSensingElementLowPassFilterAmplifier2AccelerationAmplifier13-4MotorolaSX322Fig.3-4MotorolaSX322Acc.SignalCollectingStructureProveouttestContinuoustestProveouttestsBiasBias15ContinuoustestAcc.RailAcc.RailProveoutContinuoustest3.2.1.23-5Fig.3-5AccelerometerCircuitDiagramLecroyWaveRunner6030A5V6Status3STStatus3-6163-6SX322Fig.3-6SX322WaveformAtPowerOn(NormalandZoonView)SX3223s6Selftest62.5V3.1V173-7Fig.3-7AccelerometerOutputWaveformAtCrashSimulation3-7XOUT1XOUT2PCB1+X2-X1-X2+XYOUT1YOUT2Y0WIN_PTMEEPROM3-8WIN_PTMEEPROMECUECUECU3-8Fig.3-8PTMSystemDataRecordatCrashSimulation18WIN_PTMXA/DA/DMY0810BitA/D8bit8bitA/Dconverter28=256A/Dconverter00hFFh0v~5vVpntsVbitsVDD0195.025658==Hex10.0195v80h=128×0.0195=2.496[V]01h=1×0.0195=0.0195[V]=~082h=130×0.0195=2.535[V]SX3220g2.5V,80h2.5+2.4