NASA COTS Photonics Validation Approach Construct

June23,2004NASAGoddardSpaceFlightCenterValidationofCommercialFiberOpticComponentsforAerospaceEnvironmentsMelanieN.OttMunizEngineering/NASAGoddardSpaceFlightCenterParts,Packaging,&AssemblyTechnologiesOffice301-286-0127,[e-mail]/photonicsMarch9,2005NASAGoddardSpaceFlightCenterOutline•Introduction•NASACOTSPhotonicsValidationApproach•ConstructionAnalysis•VacuumValidation•VibrationParameters•ThermalParameters•RadiationParameters•Examples:ShuttleReturntoFlight•Examples:MercuryLaserAltimeter•Examples:GeoscienceLaserAltimeter•ConclusionMarch9,2005NASAGoddardSpaceFlightCenterIntroductionChangesinOurGSFCEnvironmentShorttermprojects,lowbudgetsInstrumentslikeGLAS,MLA,VCLChangestotheMil-Specsystem,NASAreliedheavily.Telecommunicationsproductsavailable,state-of-the-art.Vendorsandpartsrapidlychanging.MostphotonicsnowCOTS.Qualificationnotonlyimpossiblebutfartooexpensive.CharacterizationofCOTSforriskmitigation.Qualitybysimilaritywherepossible.March9,2005NASAGoddardSpaceFlightCenterCOTSTechnologyAssuranceApproachForSpaceFlightSystemRequirements:Definecriticalcomponentparametersandthequantitybyhoweachcandeviatefromoptimalperformanceasaresultandduringtesting.EnvironmentalRequirementsContaminationandmaterialsrequirements.Boxlevelrandomvibration,doubleforcomponentThermalenvironment,10ChigheratextremesRadiation,worstcaseconditions.FailureModesStudy•ConditionsandParametersTestMethods•Tailoredtocapturingthelargestamountoffailuremodeswhiletestingforspaceenvironment.TestPlan•Containsnecessarytestingformissionwhilemonitoringforfailuremodes.March9,2005NASAGoddardSpaceFlightCenterQualificationPlanDefinecriticalparametersthatmustbestableduringtesting.Defineacceptablechangesinperformanceparametersasafinalresultoftestingandduringtesting(dynamicandpermanent).Definepartorsystemtobetested.Howmanysamplescanyouaffordtotest(consideringtime,equipment,materials)MaterialsAnalysis,Outgastestingforanythingunknown,takeconfigurationintoaccount.Packaging!VibrationSurvivaland“Shock”TestUsecomponentlevelsasdefinedbysystemrequirementsDefineparameterstomonitorduringtestingThermalCycling/AgingTestDefinewhichparameterswillindicatewhichfailuremodeMonitorthoseparametersduringtesting.RadiationTestingAccelerateddoserate,extrapolationmodeluseifpossible,worstconditionsAdditiontestbasedonspecificmissionrequirements?March9,2005NASAGoddardSpaceFlightCenterConstruction/MaterialsAnalysisDestructivePhysicalAnalysisIdentifypackagingissuesGasesAnalysis,hermetic?Materialsidentification,Packaging:wirebonds,dieattachmaterialsIdentifynonmetallicmaterialsforvacuumexposurePotentialcontaminationissues.ConstructionAnalysisiscrucial!LongTermReliabilityWillitsurviveharshenvironments?March9,2005NASAGoddardSpaceFlightCenterEnvironmentalParameters•Vacuumrequirements•Vibrationrequirements•Thermalrequirements•RadiationrequirementsMarch9,2005NASAGoddardSpaceFlightCenterEnvironmentalParameters:VacuumVacuumoutgassingrequirements:-ASTM-E595,100to300milligramsofmaterial125°Cat10-6Torrfor24hoursCriteria:1)TotalMassLoss1%2)CollectedVolatileCondensableMaterials0.1%-Configurationtest-Opticsorlasernearby,isASTM-E595enough?-askyourcontaminationexpert1)Useapprovedmaterials2)Preprocessmaterials,vacuum,thermal3)Decontaminateunits:simpleovenbakeout,orvacuum?March9,2005NASAGoddardSpaceFlightCenterEnvironmentalParameters:VibrationLaunchvehiclevibrationlevelsforsmallsubsystem(establishedforEO-1)Frequency(Hz)ProtoflightLevel200.026g2/Hz20-50+6dB/octave50-8000.16g2/Hz800-2000-6dB/octave20000.026g2/HzOverall14.1grmsHowever,thisisattheboxlevel,twicetheprotoflightvibrationvaluesestablishthecorrecttestingconditionsforthesmallcomponent.March9,2005NASAGoddardSpaceFlightCenterEnvironmentalParameters:VibrationLaunchvehiclevibrationlevelsforsmallcomponent(basedonboxlevelestablishedforEO-1)onthe“high”side.Frequency(Hz)ProtoflightLevel200.052g2/Hz20-50+6dB/octave50-8000.32g2/Hz800-2000-6dB/octave20000.052g2/HzOverall20.0grms3minutesperaxis,testedinx,yandzMarch9,2005NASAGoddardSpaceFlightCenterEnvironmentalParameters:ThermalThereisnostandard,typicalandbenign–25to+85C.Telcordiais–45°Cto+80°C.Dependingonthepartfortesting;InsitutestingwherepossibleAdd10°CtoeachextremeforboxlevelsurvivalThermalcyclesdeterminedbyparttype60cyclesforassembliesforhighreliability30cyclesminimumforassemblies,highrisk100ormore,optoelectronics.MoreforhighpowersystemsKnowledgeofpackagingandfailuremodesreallyhelpswithcyclesdetermination.March9,2005NASAGoddardSpaceFlightCenterEnvironmentalParameters:RadiationLEO,5–10Krads,SAAMEO,10–100Krads,VanAllenbeltsGEO,50Krads,CosmicRaysAssuming7yearmission,ShieldingfromspacecraftProtonconversiontoTotalIonizingDose(TID)At60MeV,1010protons/KradForsystemssusceptibletodisplacementdamageMarch9,2005NASAGoddardSpaceFlightCenterEnvironmentalParameters:RadiationTypicalspaceflightbackgroundradiationtotaldose30Krads–100Kradsover5to10yearmission.Doseratesforfibercomponents:•GLAS,100Krads,5yr,.04rads/min•MLA,30Krads,8yr,.011rads/min(fiveyearave)•EO-1,15Krads,10yr,.04rads/minAnyothere