Pilot-Induced Oscillation Research: Status at the End of the Century

Pilot-Induced Oscillation Research: Status at the End of the Century

150 Pages · 2015 · 3.63 MB · English

with ATTAS. Holger Duda and Gunnar Flying Qualities group of Boeing Phantom Works. The project was Mitchell et al 1994. Mitchell et al 1998.

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NASA/CP2001210389/VOL2 ¢ PilotInducedOscillationResearch: StatusattheEndoftheCentury CompiledbyMaryEShaferandPaulSteinmetz NASADrydenFlightResearchCenter Edwards,California April2001 https://ntrsnasagov/searchjsp?R=20010038125 20191001T01:09:03+00:00Z TheNASASTIProgramOfficeinProfile Sinceitsfounding,NASAhasbeendedicated totheadvancementofaeronauticsandspace scienceTheNASAScientificandTechnical Information(STI)ProgramOfficeplaysakey partinhelpingNASAmaintainthis importantrole TheNASASTIProgramOfficeisoperatedby LangleyResearchCenter,theleadcenterfor NASA'sscientificandtechnicalinformation TheNASASTIProgramOfficeprovidesaccess totheNASASTIDatabase,thelargestcollection ofaeronauticalandspacescienceSTIinthe worldTheProgramOfficeisalsoNASA's institutionalmechanismfordisseminatingthe resultsofitsresearchanddevelopmentactivities TheseresultsarepublishedbyNASAinthe NASASTIReportSeries,whichincludesthe followingreporttypes: •TECHNICALPUBLICATIONReportsof completedresearchoramajorsignificant phaseofresearchthatpresentiheresultsof NASAprogramsandincludeextensivedata ortheoreticalanalysisIncludescompilations ofsignificantscientificandtechnicaldata andinformationdeemedtobeofcontinuing referencevalueNASA'scounterpartof peerreviewedformalprofesSiona|papersbut haslessstringentlimitationsonmanuscript lengthandextentofgraphicpresentations TECHNICALMEMORANDUMScientific andtechnicalfindingsthatarepreliminaryor ofspecializedinterest,eg,quickrelease reports,workingpapers,andbibliographies thatcontainminimalannotationDoesnot containextensiveanalysis CONTRACTORREPORTScientificand technicalfindingsbyNASAsponsored contractorsandgrantees CONFERENCEPUBLICATION Collectedpapersfromscientificand technicalconferences,symposia,seminars, orothermeetingssponsoredorcosponsored byNASA SPECIALPUBLICATIONScientific, technical,orhistoricalinformationfrom NASAprograms,projects,andmission, oftenconcernedwithsubjectshaving substantialpublicinterest TECHNICALTRANSLATIONEnglish languagetranslationsofforeignscientific andtechnicalmaterialpertinentto NASA'smission SpecializedservicesthatcomplementtheSTI ProgramOffice'sdiverseofferingsinclude creatingcustomthesauri,buildingcustomized databases,organizingandpublishingresearch resultsevenprovidingvideos FormoreinformationabouttheNASASTI ProgramOffice,seethefollowing: AccesstheNASASTIProgramHomePage athttp://wwwstLnasagov EmailyourquestionviatheInternetto [email protected] °FaxyourquestiontotheNASAAccessHelp Deskat(301)6210134 •TelephonetheNASAAccessHelpDeskat (301)6210390 Writeto: NASAAccessHelpDesk NASACenterforAeroSpaceInformation 7121StandardDrive Hanover,MD210761320 NASA/CP2001210389/VOL2 PilotInducedOscillationResearch: StatusattheEndoftheCentury CompiledbyMaryEShaferandPaulSteinmetz NASADrydenFlightResearchCenter= Edwards,California_i NationalAeronauticsand SpaceAdministration DrydenFlightResearchCenter Edwards,California935230273 _L 71!_ii_i April2001 NOTICE Useoftradenamesornamesofmanufacturersinthisdocumentdoesnotconstituteanofficialendorsement ofsuchproductsormanufacturers,eitherexpressedorimplied,bytheNationalAeronauticsand SpaceAdministration Availablefromthefollowing: NASACenterforAeroSpaceInformation(CASI) 7121StandardDrive Hanover,MD210761320 (301)62!0390 NationalTechnicalInformationService(NTIS) 5285PortRoyalRoad Springfield,VA221612171 (703)4874650 Foreword "PilotInducedOscillationResearch:The_StatusattheEndoftheCentury,"aworkshop heldatNASADrydenFlightResearchCenteron68April1999,maywellbethelast largeinternationalworkshopofthetwentiethcenturyonpilotinducedoscillation(PIO) Withnearlyahundredattendeesfromteni_0untdesandthirtypresentations(plustwothat werenotpresentedbutareincludedintheproceedings)theworkshopdidindeed representthestatusofPIOattheendofthe:century Thesepresentationsaddressthemostcu_en___t)nformationavailable,addressingregulatory issues,flighttest,safety,modeling,prediction,simulation,mitigationorprevention,and areasthatrequirefurtherresearchA!lpresentationswereapprovedforpublicationas unclassifieddocumentswithnolimitsontheirdistribution Thisproceedingsincludetheviewgraphs(somewithauthors'notes)usedforthethirty presentationsthatwereactuallygivenaswellastwopresentationsthatwerenotgiven becauseoftimelimitationsFourtechnicalpapersonthissubjectthatofferthis informationinamorecompleteformar(a_IsoincludedInaddition,copiesoftherelated announcementsandtheprogramareincorporated,tobetterplacetheworkshopinthe contextinwhichitwaspresented MaryFShafer % iii q CONTENTS FOREWORD==iii VOLUME1SESSIONSIIII SESSIONI6APRIL1999_:__1 1ModelingtheHumanPilotinSingleAxisLinearandNonlinearTrackingTasks YasserZeyadaandRonaldAHess,UniversityofCalifornia,Davis3 2BandwidthCriteriaforCategoryIandI!••PIOs DavidGMitchell,HohAeronautics,Inc;andDavidHKlyde,SystemsTechnology,Inc17 3CriteriaforCategoryIPIOsofTransportsBasedonEquivalentSystemsandBandwidth KennethFRossittoandEdmundJField,BoeingPhantomWorks29 4DesigningtoPreventPIO JohnCGibson,Consultant,BritishAerospacei_41 SESSIONII6APRIL199953 5ReplicatingHAVEPIOontheNASAAmesVMS JefferySchroeder,NASAAmesResearchCente__i55 6ReplicatingHAVEPIOonAirForceSimulators BaTNguyen,AirForceResearchLaboratory65 7PredictionofLongitudinalPilotlnducedOscillationsUsingaLowOrder EquivalentSystemApproach JohnHodgkinsonandPaulTGlessner,Boeing!andDavidGMitchell,HohAeronautics,Inc67 8RecommendationstoImproveFutureP!OSimulations BrianKStadler,AirForceResearchLaboratory:2_,81 SESSIONIII7APRIL199993 9FAA'sHistorywithAPC GuyCThiel,FAA95 10PIOandtheCAA GrahamWeightman,JAA(UKCAA)107 11PIOFlightTestExperienceatBoeing(PugetSound)andtheNeedforMoreResearch BrianPLee,BoeingCommercialAirplaneGroup109 12TheEffectsonFlyingQualitiesandPIOofNonLinearitiesinControlSystems EdmundField,BoeingPhantomWorks:157 13MitigatingtheAPCThreataworkinprogress RalphA'Harrah,NASAHeadquarters171 V VOLUME2SESSIONSIVV SESSIONIV7APRIL1999179 14FlightTestingforAPC:CurrentPracticeatAirbus PierrePoncelet,AerospatialeAeronautique;andFemandoAlonso,AirbusIndustrie18l 15ThePredictionandSuppressionofPIOSusceptibilityofLargeTransportAircraft RogiervanderWeerd,DelftUniversityofTechnology189 16FlightTestingForPIO RalphHSmith,HighPlainsEngineering217 17UseofInFlightSimulatorsforPIOSusceptibilityTestingandforFlightTestTraining MichaelParrag,VeridianEngineering227 18AMethodfortheFlightTestEvaluationofPIOSusceptibility ThomasRTwisdaleandMichaelKNelson,USAFTestPilotSchool259 SESSIONV8APRIL1999269 19OnboardPIODetectionandPrevention DavidBLeggett,AirForceResearchLaboratory271 20RealTimePIODetectionandCompensation ChadwickJCox,CarlLewis,RobertPap,andBrianHall,AccurateAutomationCorporation279 21PIODetectionwithaRealtimeOscillationVerifier(ROVER) DavidGMitchell,HobAeronautics,Inc299 22PilotOpinionRatingsandPIO MichaelKNelsonandThomasRTwisdale,USAFTestPilotSchool305 23TheNeedforPIODemonstrationManeuvers VineetSahasrabudheandDavidHKlyde,SystemsTechnology,Inc; andDavidGMitchell,HohAeronautics,Inc307 VOL_3SESSIONVIANDAPPENDICES SESSIONV!8APRIL1999317 24BoeingT45GroundHandlingCharacteristics JamesGReinsberg,BoeingStLouis319 25ExtractionofPilotVehicleCharacteristicsfromFlightDatainthePresence ofRateLimiting DavidHKlyde,SystemsTechnology,Inc,;andDavidGMitchell,HohAeronautics,Inc329 26ComparisonofPIOSeverityfromFlightandSimulation ThomasJCord,AirForceResearchLaboratory343 27ASummaryoftheGroundSimulationComparisonStudy(GSCS) forTransportAircraft TerryvonKlein,BoeingPhantomWorks359 28RealExperiencesintheFrequencyDomain RandallEBaileyandAndrewMarkofski,VeridianEngineering365 29PilotModelingforResolvingOpinionRatingDiscrepancies DavidBDoman,AirForceResearchLaboratory391 a$ vi 30ClosingRemarks MaryFShafer,NASADrydenFlightResearchCenter 397 APPENDIX1:ANNOUNCEMENTS,INFORMATION,ANDPROGRAM399 1Announcementandcallforpapers401 2Informationforpresentersandattendees(sentbyemail)403 3Program_=_i409 APPENDIX2:PRESENTATIONSPRINTEDBUTNOTGIVENATTHEWORKSHOP411 1RecentResultsofAPCTestingwithATTAS HolgerDudaandGunnarDuus,DeutchesZentrumftirLuftundRaumfahrteV413 2CriteriatoSimulationtoFlightTestma_iceVersa DavidGMitchell,HobAeronautics,Inc439 APPENDIX3:PAPERSSUPPORTINGWORKSHOPPRESENTATIONS453 1DesigningtoPreventSafetyRelatedPIO JCGibson,BritishAerospaceWarton(retired),Consultant455 2PilotInducedOscillationPredictionwithThreeLevels ofSimulationMotionDisplacement JefferyASchroeder,WilliamWYChung,andDucTTran,NASAAmesResearchCenter; andSorenLaforceandNormanJBengford,SYRELogicon475 3AMethodfortheFlightTestEvaluationofPIOSusceptibility ThomasRTwisdaleandMichaelKNelson,USAFTestPilotSchool487 4PilotOpinionRatingsandPIO MichaelKNelsonandThomasRTwisdale,USAFTestPilotSchool493 vii Ses_nIV sin _179 181 UNEXPERIENCEDPILOTS STRESSFULENVIRONMENT:finalapwoach forma_flight workload heading _RUNWAYFLYt attitudeandairspeed,and_aircraft alignedontherunwaycentedine 182 183 184 185 186 COMPOSTEFLIGHT ! FLEXIBLETOOLS: _m _ydelaycanbeadjuste_J ="rscanpmv_positeif,sprays(useofmanyfeedbacksn_nv,q,)ml 187 |NITMLL ii_ml ThePredictionandSuppressionofPIO SusceptibilityofLargeTransportAircraft AnEvaluationofProposedMethods RogiervanderWeerd DelftUniversityofTechnology/AerospaceEngineering DepartmentofControlandSimulation 6Apdl1999 Prepaidandp_sentedby RogiervanderWeerd,MSc [email protected] ResearchAssociate FlightControlandSimulation tel+31(0)152789108 fax+31(0)152786480 Thispresentationisbasedontheresultsofastudymorethoroughlyreportedin: Weerd,vanderR;'PIOSuppressionMethodsandTheirEffectsonLarge TransportAircraftHandlingQualities';Thesis(MSc),DelftUniversityof Technology,Delft(TheNetherlands),January1999 ThestudywascarriedoutunderacooperativeagreementbetweenDelft UniversityofTechnologyintheNetherlandsandTheBoeingCompanyatLong BeachAstudentplacementwasmadepossibleattheStability,Controland FlyingQualitiesgroupofBoeingPhantomWorks Theprojectwascarriedoutundersupervisionof: TheBoeingCompanyDelftUniversityofTechnologE JohnHodgkinsonProfdrirJA(Bob)Muider DrEdmundJFieldirSamirBennani WaltervonKleinJr 189 |IIIIIN!* |llltlMI Contents •Introduction •PredictionofPIO AvailableCriteria CaseStudyUsingExampleAircraft •SuppressionofPIO AvailableMethods CaseStudyUsingExampleAircraft •ConclusionsandRecommendations ThestudyintoPIOhadtwomainobjectives: IInvestigateavailablemethodsforPIOprediction,includingthose recentlyproposed 2InvestigatepossibleremediestoPIO Someofthegroup'sexpertiseandexperiencewithPIOcouldbeused toevaluateandvalidatedifferentcriteriaandmethodsusingan examplelargetransportaircraftwithdifferentconfigurationsthathave handlingqualitiesthatareconsideredwellunderstood/investigated 190 cU_L iimlJnlll PredictionofPIO LimitationsofLinearMethods(CategoryI) MostobservedPIOsinvolvedratesaturationofcontrol surfaceactuator(s) •RateSaturationResultofPIO(poorCatIproperties) •Or,RateSaturationActualCauseofPIO? CatIIEvaluationrequirestheinclusionofnonlinearbehavior Thiscanbedonein •TimeDomain TimeDomainNealSmithHessMethodforNonlinearDynamics •FrequencyDomainUsingDescribingFunctionTechnique DLR'sOpenLoopOnsetPoint(OLOP) 191 litL im PredictionofPIO CategoryIExampleBandwidth TwoImportantParameters •BandwidthFrequency,(OBW ("Speed"ofSystem) •PhaseRollOff,zp ("Predictability") BodePlotof___0(j_) _)s_ck _andw_lth re,_t_,,f TheBandwidthcriterionhasbeenshowntobeawellperformingcriterionon awidevarietyofcases ExtendingBandwidthtosystemswithnonlinearelementsispossible(infact, themethodofperformingafrequencysweepinordertoestimatethesystem frequencyresponseincludesallkindsofnonlinearelementsofthereal system)RatelimitingelementsinthecommandpathoftheEFCScanbe identifiedeasilyforagiveninputamplitudeHowever,iftheratelimiting elementispartofafeedbackloop,theidentificationofthedescribing functionmayfail,astypicalnonlinearsystembehaviorgetsintoplay,egthe introductionofmultipleequilibria(limitcycles,jumpresonance) REF Hohetal1982 Mitchelletal1994 Mitchelletal1998 192 I!nl!! IRma NonlinearSystems(i) _imitCyclessustainednonlinearoscillations,fixed amplitude,fixedfrequency ConditionsforaLimitCyclearesought zQ | Useneutralstabilitycondition(Popov): C(jto)N(jto,fi)P(jto)=1 1 C(joJ)POo_)= N(jto,fi) NOte,O)isthesinusoidaldescribingfunctionrepresenation •_eo1_11o1_1_ao 193 |imllti iiIRimm NonlinearSystems(ii) JumpResonance Nouniquerelationanymorebetween frequencyandgain/phaseofclosed loopresponse PhaseJumpinPilotVehicleSystem 0 MisadaptationbyPilot PIO 15 10 S _o 04O lS mop_ i, a E |5_)1DO*SG 194 ilil!!!t IWILHi PredictionofPIO CategoryIIExampleOLOP yU eFlight't rheIPilot__II,r_,_1Bare, '_'_9_mi(PureGa{n)li_St'y°tet_i"T:FLT___"_AirframeF]I t/RateLimitl 0 RatelimitingcausesJumpResonance OLOPdetermines"theconsequence",, 4,Cl Pie _i7,__ OLOPis Luc0J=TTU(OoosetJ "_"_;oc, Attheonsetfrequency i_r,, •_/_OLOP _lo_ItP__x)OLOP REF Duda1997 Dudaetal1997 195 Ii!i illi CaseStudyConfigurations OfTheExampleAircraft •ReceiverAerialRefuelingTask CleanConfiguration HighSpeed,M=0613 HighAltitude,h=20,000ft •PitchRateCommandSystemConfigurations: OldSoftwareVersionF UpdatedSoftwareVersionH AddedPhaseLagst_=[01,025] •Simplifications SingleAxis NoModelUncertainties NoStructuralDynamics >PIOPRONE >PIOFREE TheExampleAircraft HighPerformanceFlyByWireMilitaryCargoAirplane Highwing,fourengines,TtailconfigurationLength175ft,height55ft, wingspan170ft,MTOW600,000lbs 'Highgain'missiontasksinclude:Landing/TakeoffShortAustereAirfieldsand AerialReceiverRefuelingPIOswereencounteredduringdevelopmentalflight testingforbothtasks[1],[2] Configurations ApartfromconfigurationsrepresentingoldandupdatedElectronicFlightControl System(EFCS)softwareversions,additionalconfigurationswereevaluatedthat representtheupdatedEFCSsoftwarewithintentionallydeteriorated characteristics Thelatterisaccomplishedbyaddingphaselagsintheflightcontrolsystemby increasingthetimeconstantofafirstorderfilterresidinginthecommandpathof thecontrollaws REF Iloputaifeetal1996 Iloputaife1997 196 11111111t |lutlgli PitchAxisPIOEvent EFCSSoftwareVersionF Pilotinitiatedemergency breakawayfromtanker TypicalcategoryIIPIO: •"Highpilotgain" •"Pilotis180°outofphase" withpitchattitude •Softwareratelimitingof elevatorcommandsignal [RefIloputaife1997,Iloputaifeeta11996] _:PitchStickPositionI'inJ_pull r_"_"push PitchA_tude[de_] L1 ,tlJ Elevato_DeflecSo_[dog] AJrlpeed[KIAS]"_= REF Iloputaifeetal1996 Iloputaife1997 197 llll|I, irma ExampleAircraft ControlLawChanges 2 _t_er PCIo)|Io AillaimlI_ q_nlo_II Maindifferencesbetweenoldandnewsoftware 1Structuralfilteringoptimization)increasesystembandwidth 2Stickshapingchange)reducecontrolsensitivity 3Changeratelimits)fullyuseactuatorcapability [Reflloputaife1997,11oputaifeeta11996] REF Iloputaifeetal1996 lloputaife1997 198 OmTm_|L illtmi BandwidthCriterion ValidationUsingExampleAircraft __PIO_SusceptlbTe PIOSucptleifFlightPathBandwidthInsufficient I;F,,,o"* o_,0III,,o INo,,o (|_:",)a PitchAttitudeBandwidth"_'w[tad/s} •PlO _'NoPlO _"ApproachFlightTeSt B2°AO_I RefuellrlgFliOhlTest "FlightTest 0NoPIOX15 FSghtTest mP_O r'lNoPIg Exmm_Aln;refl FlightTest "Source:Klyde,OH04a11995 Criterionmappingisnotconsideredto besuccessfuldiscriminationsinceflight pathbandwidthissufficientforboth configurations 711 |, ), _0, i o; t_ i3FC_bel_ osiis32S13S4aS P__tu__a_,_a_w_Svvmata[rl_=] 199 elmlBL& |u OLOPCriterion ApplicationtoExampleAircraft ilot "_iCUT Pilot p,,ch cAi 1AssumepuregainpilotthatexertssinusoidalsticksignalwithcertainamplitudeIrl 2Determinetheonsetfrequenciesofallratelimitingelementsusing _Thisequaf_oncanbesoJved ,__2t}G'c:"Igraphically 3Atthecriticalratelimiter,cutloop,plotlooptransferfunctiononNicholsChart 4OLOPispointonlocusforo_=_Oo,,_ItspositioncanberelatedtoCategoryIIPtO susceptibility 12 2OO ira!& NitKml OLOPCriterion EFCSSoftwareVersionF(old) OnsetFrequencies InnerLoop¢Oor_et=205rad/s OuterLoop(donset=353rad/s __,;_i:_i,:,!, 13 201 iIIIIIIIIJlL& 1411uulu OLOPCriterion ValidationUsingExampleAircraft [: ;j:,"":',i; 'i"""•':::" _i': r:NoC_Iq_ryUPlQ',;" _1¢Iti, •PIO _7NoPIO 0P_O 0NoPIO •PIO DNoP_O SDg_O_u_e"F'_ht"re=t "FhghlTel_t Exiling=_I_FP_F'_ghtTl_t •Source:Oucla,H1_197 2O2 ,m,ResCohensi ,,,,,,ultsmpreve° CriteriaValidation ResultsCategoryICriteria LOESBandwidthGibsonSmithHessNeaISmith CAPtGeddes FCEFCS(F)//LI/no/no/noLl/no4 FCEFCS(H)LI/12/Ll/no/no/noLllnoLI/ ResultsCategorytlCriteria HessOLOPTimedomain NonlinearNeaISmith FC,EFCS(F)yesyesyes FCEFCS(H)nonono L1,L2,L3 yes,no Note: EFCSversionFshowedPIOtendencies EFCSversionHistheupdated,PlOfreeconfiguration predictedCHR PredictedPIO suscul_t_ility Crileriondoesn't includeprediction 203 CUMII|& |N_tmm RemedytoPIO "Conventional"Methods •ChangeHardware Actuators FeelSystemCharacteristics •ChangeControlLaws ControlAllocation/Architecture ControlSensitivity" ReducePhaseLags/Filtering" "Alternative"Methods •PIOSuppressionFilter TailSize etc SystemBandwidth" LoopGains" etc AttenuatePilotCommandAtPredefinedPilotOperatingConditions SoftwareRateLimitersWithPhaseCompensation ReducePhaseLossUnderRateSaturation •Thesemethodswm'eappliedduringthed_elopn'_nlofth_examplealrcm__F___ 16 OnmostcasesofPIOexperiencedinthepast,theproblemswerediscoveredin arelativelylatephaseofdevelopment,oreven,duringroutineoperationA solutionthatallowstheestablishedcontrollawstructuretoremainthesame whileeliminatingPIOsusceptibilitysurelyispreferable Goal:LookformethodsthatsolvethePIOproblemwithouthavingtoredesign

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