EVALUATION AND COMPARISON OF HELICOPTER SIMULATION MODELS WITH DIFFERENT ...

94 Pages·2008·4.7 MB·English

1
EVALUATIONANDCOMPARISONOFHELICOPTERSIMULATIONMODELSWITH
DIFFERENTFIDELITIES
ATHESISSUBMITTEDTO
THEGRADUATESCHOOLOFNATURALANDAPPLIEDSCIENCES
OF
MIDDLEEASTTECHNICALUNIVERSITY
BY
DEN˙IZYILMAZ
INPARTIALFULFILLMENTOFTHEREQUIREMENTS
FOR
THEDEGREEOFMASTEROFSCIENCE
IN
AEROSPACEENGINEERING
JULY2008
Approvalofthethesis:
EVALUATIONANDCOMPARISONOFHELICOPTERSIMULATIONMODELSWITH
DIFFERENTFIDELITIES
submittedbyDENI˙ZYILMAZinpartialfulfillmentoftherequirementsforthedegreeof
Master of Science in Aerospace Engineering Department, Middle East Technical Uni-
versityby,
Prof. Dr. CananO¨zgen
Dean,GraduateSchoolofNaturalandAppliedSciences
Prof. Dr. ˙IsmailH.Tuncer
HeadofDepartment,AerospaceEngineering
Dr. ˙IlkayYavrucuk
Supervisor,AerospaceEngineeringDept.,METU
ExaminingCommitteeMembers:
Prof. Dr. CahitC¸ıray
AerospaceEngineeringDept.,METU
Dr. ˙IlkayYavrucuk
AerospaceEngineeringDept.,METU
Prof. Dr. OzanTekinalp
AerospaceEngineeringDept.,METU
Assist. Prof. Dr. Og˘uzUzol
AerospaceEngineeringDept.,METU
Assist. Prof. Dr. NilaySezerUzol
MechanicalEngineeringDept.,
TOBBUniversityofEconomicsandTechnology
Date:
Iherebydeclarethatallinformationinthisdocumenthasbeenobtainedandpresented
in accordance with academic rules and ethical conduct. I also declare that, as required
bytheserulesandconduct,Ihavefullycitedandreferencedallmaterialandresultsthat
arenotoriginaltothiswork.
Name,LastName: DEN˙IZYILMAZ
Signature :
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ABSTRACT
EVALUATIONANDCOMPARISONOFHELICOPTERSIMULATIONMODELSWITH
DIFFERENTFIDELITIES
Yılmaz,Deniz
M.S.,DepartmentofAerospaceEngineering
Supervisor : Dr. ˙IlkayYavrucuk
July2008,76pages
This thesis concerns the development, evaluation, comparison and testing of a UH-1H heli-
copter simulation model with various fidelity levels. In particular, the well known minimum
complexitysimulationmodelisupdatedwithvarioushigherfidelitysimulationcomponents,
such as the Peters-He inflow model, horizontal tail contribution, improved tail rotor model,
controlmapping,groundeffect,fuselageinteractions,groundreactionsetc. Resultsarecom-
pared with available flight test data. The dynamic model is integrated into the open source
simulationenvironmentcalledFlightGear. Finally,themodeliscross-checkedthrougheval-
uationsusingtestpilots.
Keywords: helicopter,simulation,fidelity,mathematicalmodeling
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¨
OZ
GERC¸EKC¸˙IL˙IG˘˙IDEG˘˙IS¸KENHEL˙IKOPTERMODELLER˙IN˙INDEG˘ERLEND˙IR˙ILMES˙I
VEKARS¸ILAS¸TIRILMASI
Yılmaz,Deniz
Yu¨ksekLisans,HavacılıkveUzayMu¨hendislig˘iBo¨lu¨mu¨
TezYo¨neticisi : Dr. ˙IlkayYavrucuk
Temmuz2008,76sayfa
Butezdeg˘is¸ikgerc¸ekc¸ilikseviyeleriolanUH-1Hhelikoptersimu¨lasyonmodelleriningelis¸tirilmesini,
testinivekars¸ılas¸tırılmasınıic¸erir. Literatu¨rdeiyibilinen”minimumcomplexity”simulasyon
modelininkontroldag˘ıtımı,yataykanatcıkaerodinamig˘i,rotoric¸ akıs¸ı,go¨vde,yeretkiles¸imi
gibiyenibirimlerilegerc¸eklikseviyesiartırıldı. Sonuc¸laruc¸us¸ testverisiilekars¸ılas¸tırıldıve
testpilotlarıtarafındansimulasyonortamındadenendi.
AnahtarKelimeler: helikopter,simu¨lasyon,gerc¸ekc¸ilik,matematikselmodelleme
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Tomyfamily
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ACKNOWLEDGMENTS
I would like to express my sincere gratitude to Dr. ˙Ilkay Yavrucuk who supervised in all
stepsofthisworkandprovidedthenecessaryresourcesofhisknowledgeandexperience. His
energy,supportandguidancehelpedmetocompletethiswork.
I would like to thank Prof. Dr. Cahit C¸ıray for setting the first light about helicopters in my
mind during my undergraduate years. Also, many thanks to Assoc. Prof. Dr. SerkanO¨zgen
for encouraging me to start my master thesis about helicopter simulation. Special thanks to
Prof. Dr. OzanTekinalpandAssist. Prof. Dr. Og˘uzUzolfortheirassistanceandsuggestions.
I wish to state my thanks to the Teoman O¨zmen, who has never turned down my specific
requests about UH-1H helicopters and simulators located in helicopter maintenance center
militarybase.
IwishtostatemayendlessthankstoOnurTarımcıandS¸evketEserKubalı. Iprobablywould
not be able to finish my thesis without their help about coding and integration to simulation
environment. IwouldliketothankO¨zlemCeyhanandAdnanCeyhanforsharingmywhole
thesis progress. I appreciate the useful discussions we had with Volkan Kargın and Hilal
Erc¸in. I can not forget the assistance of Tolga Yapıcı, Tahir Turgut and Emre Altuntas¸ about
latex formating. I also would like to thank Gu¨rsu Tas¸ar, Alper Ezertas¸ and Go¨khan Ahmet
for always being on my side during the thesis. Thanks to Dr. Mustafa Kaya for his supports
too. I would like to thank all my friends working in the same laboratory; Burcu Akın, Tuba
C¸ig˘dem Elmas, Sinem Is¸ık, Zeynep C¸akır and Onur Tarımcı for supporting me whenever I
needed. Also many thanks to my friends, Burcu C¸akın Erdog˘an and Bus¸ra Akay who had
been far away but close enough to share my thesis progress. Special thanks to all aerospace
engineeringdepartmentstafffortheirkindresponses.
Finally, I would like to express my deepest thanks to my parents for their endless support
throughout my life. Also, this thesis is supported by the 106M069 project of The Scientific
andTechnologicalResearchCouncilofTurkey(TUBITAK).
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TABLE OF CONTENTS
ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
O¨Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
DEDICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
ACKNOWLEDGMENTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
TABLEOFCONTENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
LISTOFTABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x
LISTOFFIGURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
CHAPTERS
LISTOFABBREVIATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1 INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 MATHEMATICALMODELING . . . . . . . . . . . . . . . . . . . . . . . 9
2.1 MainRotorModeling . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2 StabilizerBarModeling . . . . . . . . . . . . . . . . . . . . . . . . 18
2.3 TailRotorModeling . . . . . . . . . . . . . . . . . . . . . . . . . . 19
2.4 HorizontalTailModeling . . . . . . . . . . . . . . . . . . . . . . . 20
2.5 VerticalTailModeling . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.6 FuselageModeling. . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.7 SkidModeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
2.8 GroundSurfaceReactionModeling . . . . . . . . . . . . . . . . . . 24
2.9 Altitudeandthrustcoefficientupdating . . . . . . . . . . . . . . . . 26
2.10 GroundEffectModeling . . . . . . . . . . . . . . . . . . . . . . . . 27
2.11 OtherUpdates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
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3 TRIMMINGUSINGAFLIGHTCONTROLLER . . . . . . . . . . . . . . . 31
3.1 InnerLoopController . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.2 OuterLoopController . . . . . . . . . . . . . . . . . . . . . . . . . 33
4 SIMULATIONRESULTSANDMODELVERIFICATION . . . . . . . . . 37
4.1 TrimConditionValidation . . . . . . . . . . . . . . . . . . . . . . . 37
4.2 DynamicResponseValidation . . . . . . . . . . . . . . . . . . . . . 41
4.2.1 HoverCondition . . . . . . . . . . . . . . . . . . . . . . 42
4.2.1.1 PilotCollectiveStepInput . . . . . . . . . . 42
4.2.1.2 PilotLongitudinalCyclicStepInput . . . . . 44
4.2.1.3 PilotLateralCyclicStepInput . . . . . . . . 46
4.2.1.4 PilotPedalStepInputtoHover . . . . . . . . 48
4.2.2 60KnotsForwardFlightCondition . . . . . . . . . . . . 50
4.2.2.1 PilotCollectiveStepInput . . . . . . . . . . 51
4.2.2.2 PilotLongitudinalCyclicStepInput . . . . . 53
4.2.2.3 PilotLateralCyclicStepInput . . . . . . . . 55
4.2.2.4 PilotPedalStepInput . . . . . . . . . . . . . 57
4.3 PilotEvaluationinRealTimeSimulation . . . . . . . . . . . . . . . 58
4.3.1 IntegrationIntoaSimulationEnvironment . . . . . . . . . 58
4.3.2 PilotEvaluation . . . . . . . . . . . . . . . . . . . . . . . 60
5 CONCLUSION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
5.1 FutureWork . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
REFERENCES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
A GEOMETRYSPECIFICATIONSOFTHEUH-1HHELICOPTER . . . . . . 69
B MAINROTORINFLOWDISTRIBUTIONS . . . . . . . . . . . . . . . . . 70
B.1 LongitudinalStepInputto60KnotsTrimmedFlight . . . . . . . . . 71
B.2 LateralStepInputto60KnotsTrimmedFlight . . . . . . . . . . . . 76
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