critical design review
DESCRIPTION
Purdue University AAE 451 Fall 2006 Team FORE. Critical Design Review. Tung Tran Matt Drodofsky Haris Md Ishak Matt Lossmann. Mark Koch Ravi Patel Ki-Bom Kim Andrew Martin. Presentation Overview. Mission Requirements Aerodynamics Aspect and Taper Ratio Wing Selection Analysis - PowerPoint PPT PresentationTRANSCRIPT
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Critical Design ReviewCritical Design Review
Tung TranMatt DrodofskyHaris Md IshakMatt Lossmann
Purdue UniversityPurdue UniversityAAE 451AAE 451Fall 2006Fall 2006Team FORETeam FORE
Mark KochRavi PatelKi-Bom KimAndrew Martin
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PresentationPresentation OverviewOverview
PropulsionPropulsionMotor SelectionMotor SelectionBattery SelectionBattery SelectionHigh Speed FlightHigh Speed Flight
Propeller PropertiesPropeller PropertiesMotor PropertiesMotor Properties
Endurance FlightEndurance FlightPropeller PropertiesPropeller PropertiesMotor PropertiesMotor Properties
Dynamics & ControlDynamics & ControlTail Surface SizingTail Surface SizingControl Surface SizingControl Surface SizingYaw Rate Control Feedback Yaw Rate Control Feedback systemsystem
Build ScheduleBuild ScheduleFlight TestFlight Test
Static TestStatic TestDynamic TestDynamic Test
Mission Requirements
AerodynamicsAspect and Taper Ratio
Wing Selection Analysis
StructuresLanding Gear
Weight DeterminationWeight Determination
List of ComponentsList of Components
Wing Tip Vertical Wing Tip Vertical DeflectionDeflection
Bending Moment StudyBending Moment Study
Skin and MaterialSkin and Material
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Mission RequirementsMission Requirements
High Speed Autonomous Unmanned High Speed Autonomous Unmanned AircraftAircraft
1 lb payload measuring 2.5x4x3 in1 lb payload measuring 2.5x4x3 in Takeoff and Landing Distance of 120 ftTakeoff and Landing Distance of 120 ft Minimum Climb Angle 35Minimum Climb Angle 35oo
Stall Velocity <= 30 ft/secStall Velocity <= 30 ft/sec Dutch Roll Damping > 0.8Dutch Roll Damping > 0.8 Budget Cost $250.00Budget Cost $250.00
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3 View Drawing3 View Drawing
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3-D Picture3-D Picture
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Aspect RatioAspect Ratio
Minimize Drag (Induced vs. Skin Friction)Minimize Drag (Induced vs. Skin Friction) Skin Friction DragSkin Friction Drag
Turbulent Flat Plate ApproximationTurbulent Flat Plate Approximation
Induced DragInduced Drag
58.210 Relog
455.0
l
fC
planform
wingwetfD S
SCC
f
eARk
ARe
1
64.0045.0178.1 68.0
LD kCCi
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Drag vs. Aspect RatioAt Various Flight Speed
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 2 4 6 8 10 12 14 16 18 20 22
Aspect Ratio
Drag
[lbf
]
V= 130 ft/s
V= 40 ft/s
AR=2.1
AR=17
Wing Aspect Ratio Optimization For High-Speed and Low-Speed Flight
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1.2
1.4
1.6
1.8
2
2.2
0 2 4 6 8 10 12 14 16 18 20 22
Aspect Ratio
Drag
[ lbf
]AR=7
Aspect RatioAspect Ratio
Wing Span = 5.44 ft @ Wing Span = 5.44 ft @ AR = 7AR = 7
V = 49 ft/sV = 49 ft/s
V = 130 ft/sV = 130 ft/s
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Taper RatioTaper Ratio Best Taper Ratio: 0.45 (Best Taper Ratio: 0.45 (ellipticalelliptical = 0) [Anderson] = 0) [Anderson]
Induced DragInduced Drag
Fourier CoefficientsFourier Coefficients
SummationSummation
1.27% C1.27% CDiDi Increase v. Elliptical Lift Increase v. Elliptical Lift DistributionDistribution
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
0.09
0.1
Taper Ratio
Del
ta
AR=7
Min Taper = 0.449
N
ni
i
in
N
nin
i
nnAA
c
b
11 sin
sinsin
2
N
n
n
A
An
2
2
1
12
AR
CC L
Di
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Constraints:
Required CLmax at Vstall = 30 ft/s.
Reynolds Number ≈ 100,000
Source : UiUC Windtunnel Data
Martin Hepperle MH45Martin Hepperle MH32Selig/Donovan SD7032
CLmax required depends on
Wing Loading.
W/S = 1.29 [ lbf/ft2 ]
3-D CLmax = 1.21 [with flaps]
2-D CLmax = 1.09 [without flaps]
Reynolds Number ≈ 100,000Airfoil SelectionAirfoil Selection
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Martin Hepperle MH45Martin Hepperle MH32Selig/Donovan SD7032
Source : UiUC Windtunnel Data
Coefficient of Drag at Vdash = 130 ft/s:
Profile Coefficient of Drag
From Drag Polar
Coefficient of Induced Drag
Function of Coefficient of Lift
Minimum CDi Occurs at the lowest CL:
MH45 has lowest CL at minimum CD
Reynolds Number ≈ 300,000
Airfoil SelectionAirfoil Selection
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Tail SelectionTail Selection Airfoil Section Chosen to:Airfoil Section Chosen to:
Have low dragHave low drag ManufacturabilityManufacturability
Horizontal TailHorizontal Tail NACA 0009NACA 0009
Vertical TailVertical Tail NACA 0009NACA 0009
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Wing AnalysisWing Analysis MH45 Wing Analysis [Raymer & Brandt]MH45 Wing Analysis [Raymer & Brandt]
Conversion between 2-D and 3-DConversion between 2-D and 3-D2-D 2-D
Re Re 100,000100,000
2-D 2-D
Re Re 485,000485,000
3-D 3-D
Re Re 100,000100,000
3-D 3-D
Re Re 485,000485,000
UnitsUnits
5.6155.615 6.2046.20411
4.2574.25744
4.6434.64322
1/1/radrad
0.2050.20555
0.0900.09044
0.1850.18500
0.0840.08411
----
1.1211.121 ---- 1.0081.00899
---- ----
12.3612.36 ---- 13.3613.36 ---- degdeg
1.41.4 ---- 1.2151.21533
---- ----
8.368.36 ---- 1010 ---- degdeg
LCeAR
C
CC
l
lL
1
0LC
maxLC
00
9.0 lL CC
maxmax
9.0 lL CC
max oo 5.11max
flappedLCmax,
flappedmax,
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Flap AnalysisFlap Analysis 2-D Analysis in XFOIL2-D Analysis in XFOIL
3535o Deflection (0.15c) Deflection (0.15c)
Convert to 3-D Convert to 3-D [Raymer][Raymer]
o
lC
4
419.0
max
max
..
.2max,max,max,
.
cos
cos9.0maxmax
lh
f
lhf
Dcleanflapped
lhf
lL
S
SS
SS
SCC
flapped area over wing area
angle of hinge line to center line
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Landing Gear AnalysisLanding Gear Analysis
Assumptions: [Raymer]Assumptions: [Raymer] Main Landing Wheels support 90% of Main Landing Wheels support 90% of
weights.weights. Taildragger aft tires are about a quarter Taildragger aft tires are about a quarter
to a third the size of the main tires. to a third the size of the main tires. Tire sizing:Tire sizing:
Diameter : 0.1633ft (1.96 in)Diameter : 0.1633ft (1.96 in) Width: 0.075ft (0.9 in)Width: 0.075ft (0.9 in)
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Longitudinal tip-over analysis Longitudinal tip-over analysis [Raymer][Raymer]
Angles between most aft/most forward CG and main landing gear should be between 16 to 25 degrees.
The tail-down angle should be between 10 to 15 degrees
Lateral tip over analysis
Main wheels should be more than 25 degrees laterally from Center of Gravity.
Tip-over AnalysisTip-over Analysis
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Wing AssemblyWing Assembly
Wing Mount
Complete wing assembly with fiberglass cover
Leading Leading EdgeEdge
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Skin Materials Trade Skin Materials Trade StudyStudy
Balsa
WoodFiber
GlassUnits
Shear Modulus 23600 1000000 psi
Density 9.68 117.41 lbm/ft3
Required Skin Thickness 0.0684 0.00162 ft
Volume 0.2895 0.0068 ft3
Weight 2.8017 0.8037 lbs
Purpose: Compare weight of skin made of different materials
Method: Single cell Thin-walled analysis
Result: Fiber glass has lowest weight
t
dsq
GA2
1
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Skin & MaterialSkin & Material
GRP (Glass Reinforced plastic) wing GRP (Glass Reinforced plastic) wing covering (fiber glass w/ epoxy)covering (fiber glass w/ epoxy)
3oz E Glass Satin WeaveThickness: 0.0046“(Two layer 0.0092’’)
Epoxy hardener (205(fast) +206(slow))
Epoxy Resin (105)
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List of ComponentsList of Componentscomponent material weight (lb)
internal body balsawood 0.1444
main wing foam + fiber glass 1.2750
vertical wing foam + fiber glass 0.0946
horizontal stabilizer foam + fiber glass 0.2214
fuselage foam 0.1935
wing Mount balsawood + foam 0.0181
nose cap fiber glass 0.0773
motor (w/ gear box) 0.8000
gyro 0.0400
servo (rudder,elevator,flaperon) 0.3791
receiver 0.0397
speed control 0.1000
battery 0.5000
landing gear 0.1243
payload 1.0000
total (including battery payload) 5.0074
(excluding battery and payload) 3.5074
Total Weight:
5.0074 lb
(excluding control wires, hinges and glue)
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CG DeterminationCG Determination Center of gravity:Center of gravity:
m
m
dm
xdmx
m
m
dm
zdmy
Center of gravity
Moment of inertia (results from CATIA)
GGxx (in) (in) GGyy (in) (in) GGzz (in) (in)
11.8311.83 1.231.23 00
IIxx (slug*ft(slug*ft22)) IIyy IIzz IIxyxy IIxzxz IIyzyz
0.1340.134 0.3130.313 0.1850.185 -0.005-0.005 -1.731e-5-1.731e-5 -1.613e-5-1.613e-5
XX
YY
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Bending Moment StudyBending Moment Study
(psi) 210000
glassfiber
ofstrength Tensile
)199070(psi x
x I
My
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Wing Tip Vertical Wing Tip Vertical DeflectionDeflection
Vertical deflection of wing tip
0.1167ft (1.4in)
EI
Mxx
2)(
2
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Catia ModelCatia Model
BenefitsBenefits VisualizationVisualization Moment of InertiaMoment of Inertia CG CalculationCG Calculation Weight EstimationWeight Estimation CNC ManufacturingCNC Manufacturing
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Battery SelectionBattery Selection A123 Racing Lithium A123 Racing Lithium
Ion batteriesIon batteries 5 cells5 cells 70A continuous 70A continuous
dischargedischarge 2300mAh per cell2300mAh per cell 3.6 V per cell3.6 V per cell 70 grams per cell70 grams per cell
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Motor SelectionMotor Selection
Motor InformationMotor Information AXI 2826/10 Gold lineAXI 2826/10 Gold line
3-5 lipo cells3-5 lipo cells Kv - 920 RPM/VKv - 920 RPM/V Max Continuous – 30AMax Continuous – 30A Max Burst – 42AMax Burst – 42A Acceptable Props: Acceptable Props:
10x8-13x1010x8-13x10
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High Speed MissionHigh Speed Mission
Propeller PropertiesPropeller Properties 10 in propeller10 in propeller 8 in pitch8 in pitch Advance Ratio - .73Advance Ratio - .73 Propeller Efficiency - .85Propeller Efficiency - .85 Cp - .0404Cp - .0404 Ct - .0468Ct - .0468 RPM – 12909rpmRPM – 12909rpm Output Power – 327.3 Output Power – 327.3 ft-ft-
lbf/seclbf/sec
High Speed = 130 High Speed = 130 ft/secft/sec
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High Speed MissionHigh Speed Mission
Motor PropertiesMotor Properties Power Out – 525 wattsPower Out – 525 watts Input Current – 39.1AInput Current – 39.1A Input Voltage – 14.2VInput Voltage – 14.2V RPM – 12908rpmRPM – 12908rpm Motor efficiency - .95Motor efficiency - .95
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Endurance MissionEndurance Mission
Fly Fly endurance endurance mission at mission at 49ft/s49ft/s
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Endurance MissionEndurance Mission Propeller Propeller
PropertiesProperties 12 in diameter12 in diameter 8 in pitch8 in pitch Advance Ratio - .67Advance Ratio - .67 Propeller Efficiency Propeller Efficiency
- .85- .85 Cp - .03Cp - .03 Ct - .037Ct - .037 RPM – 4385rpmRPM – 4385rpm Output Power – 23.2 Output Power – 23.2 ft-ft-
lbf/seclbf/sec
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Endurance MissionEndurance Mission Motor PropertiesMotor Properties
Power Out – 36 wattsPower Out – 36 watts Input Current – 9.3AInput Current – 9.3A Input Voltage – 4.8VInput Voltage – 4.8V RPM – 4385rpmRPM – 4385rpm Motor efficiency - .81Motor efficiency - .81 51 min flight time51 min flight time
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Class II Sizing of Tail Area (Horizontal & Vertical Surfaces)
MAC = 0.815 ft (9.78 in)
CG Range = 0.184MAC – 0.327MAC
CG Location = 0.235MAC
AC Location = 0.4153MAC
Static Margin = 18%
Static Margin Range = 14 %
0 0.5 1 1.50
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1Static Margin based on Horizontal Tail Area
Horizontal Tail Area [ft2]
xbar
ac A
and
xba
r cg af
t []
Xcgaft
XacA
Sh = 1.0 ft2
Longitudinal Static Stability Longitudinal Static Stability CCmmαα
=-1.6265 rad=-1.6265 rad-1-1
Usually negativeUsually negativeSv = 0.4 ft2
Weathercock StabilityWeathercock Stability CCnnββ
=0.10193 rad=0.10193 rad-1-1
typically 0.06 to 0.2typically 0.06 to 0.2RoskamRoskam
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SummarySummary
Wing Horizontal Tail Vertical Tail Units
AR 7 4 2.3 []
Taper Ratio 0.45 0.72 0.6 []
Area 4.23 1 0.4 [ft2]
Span 5.44 2 0.9583 [ft]
MAC 0.815 0.5 0.54167 [ft]
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Control SurfacesControl Surfaces
eLhLLLLehi
CiCCCC
0 emhmL
L
mm
ehiCiCC
dC
dCC 00
Trim Diagram [Roskam]Trim Diagram [Roskam]Horizontal Stabilizer Incidence Angle = -1Horizontal Stabilizer Incidence Angle = -1oo
Max Trim Elevator Deflection Angle = -15Max Trim Elevator Deflection Angle = -15oo
High Speed CHigh Speed CLL = 0.08 = 0.08Flaperon
Span 3 ft
Chord 0.16667 ft
η_ia 0.35Spanw ft
η _oa 0.9Spanw ft
Elevator
Span 2 ft
Chord 0.1 ft
Rudder
η_v_ir 0.2083Spanv ft
η_v_or 0.9583Spanv ft
Chord 0.375 ft
Historical Data: Cessna Skywagon
Pitch, elevator sizePitch, elevator size CCmmδδee
=-2.6408=-2.6408
typically -1 to -2typically -1 to -2Yaw and/or roll, Yaw and/or roll, rudder sizerudder size CCnnδδrr
=-0.1002=-0.1002
typically -0.06 to -typically -0.06 to -0.120.12Roll, flaperon sizeRoll, flaperon size CCllδδaa
=0.285=0.285
typically 0.05 to typically 0.05 to 0.20.2
o10max
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Modal ParametersModal ParametersOpen LoopOpen Loop
Phugoid modePhugoid mode Damping Ratio: 0.495Damping Ratio: 0.495 Natural Frequency: 0.2582 Natural Frequency: 0.2582 radrad//secsec
Short Period modeShort Period mode Damping Ratio: 0.934Damping Ratio: 0.934 Natural Frequency: 13.248 Natural Frequency: 13.248 radrad//secsec
Dutch Roll modeDutch Roll mode Damping Ratio: 0.2014Damping Ratio: 0.2014 Natural Frequency: 8.355 Natural Frequency: 8.355 radrad//secsec
Roll modeRoll mode Time Constant: 0.49 secTime Constant: 0.49 sec
Spiral modeSpiral mode Time Constant: 54.91 secTime Constant: 54.91 sec
OgataOgata
n
22dn j
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Dutch Roll Feedback Block Dutch Roll Feedback Block DiagramDiagram Nominal Gain: -0.11Nominal Gain: -0.11
Dutch Roll closed loopDutch Roll closed loop Damping Ratio: 0.841Damping Ratio: 0.841 Natural Frequency: 10.9 Natural Frequency: 10.9
radrad//secsec
Aircraft and Servo Transfer Function
950 + s 40 + s^2
950
)950402^)(79.69368.32^)(07673.0)(369.8(
)161.14425.02^)(355.8(69673
ssssss
sss
)81.69367.32^)(07672.0)(366.8(
)161.14426.02^)(354.8(3431.73
ssss
sssAircraft Transfer FunctionServo Transfer Function
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Root Locus of Control Root Locus of Control SystemSystem
Closed Loop Poles for Yaw Rate feedback to RudderClosed Loop Poles for Yaw Rate feedback to Rudder
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Build ScheduleBuild Schedule
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Flightline TestsFlightline TestsStatic TestStatic Test (Purdue Airport)(Purdue Airport)
Rate Gyro Gain setting – Correct DeflectionRate Gyro Gain setting – Correct DeflectionTransmitter Receiver operationTransmitter Receiver operationControl Surface operationControl Surface operationPropulsion operationPropulsion operation
Dynamic TestDynamic Test (McAllister Park)(McAllister Park)Taxi Run – Landing Gear and Tail Wheel controllabilityTaxi Run – Landing Gear and Tail Wheel controllabilityRate Gyro Gain setting – Correct MagnitudeRate Gyro Gain setting – Correct MagnitudeFirst flight: (Yaw feedback control off)First flight: (Yaw feedback control off)
Brief liftoff and land to feel initial handing qualities of aircraftBrief liftoff and land to feel initial handing qualities of aircraftSecond flight:Second flight:
Sustaining flight with turns to evaluate aircraft stability and Sustaining flight with turns to evaluate aircraft stability and controlcontrol
Third flight:Third flight:Go through procedures to set rate gyro gain.Go through procedures to set rate gyro gain.
FULL THROTTLE FLIGHT!FULL THROTTLE FLIGHT!
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ReferencesReferences
Brandt, Steven. Et al. Introduction to Aeronautics: Brandt, Steven. Et al. Introduction to Aeronautics: A Design Perspective. 1997.A Design Perspective. 1997.
Raymer, D. Aircraft Design: A Conceptual Raymer, D. Aircraft Design: A Conceptual Approach. Forth Edition. 2006.Approach. Forth Edition. 2006.
Stevens, B., Lewis, F. Aircraft Control and Stevens, B., Lewis, F. Aircraft Control and Simulation. 2003.Simulation. 2003.
Anderson, J. Fundamentals of Aerodynamics. 2001.Anderson, J. Fundamentals of Aerodynamics. 2001. Callister, W. D. Material Science & Engineering 2nd
edition. 2005. Sun, C. T. Mechanics of Aircraft Structures. 1998.Sun, C. T. Mechanics of Aircraft Structures. 1998.
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Questions?Questions?