msd 1 week 6 system design review team 15462 rochester institute of technology college of...
TRANSCRIPT
P15462
MSD 1 WEEK 6 SYSTEM DESIGN REVIEW
Team 15462Rochester Institute of Technology
College of Engineering
10/2/2014 1
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AGENDA
Background (10 minutes) Problem Statement Customer Needs Engineering Requirements Week 3 action item review
10/2/2014
System Analysis Functional Decomposition Areas of Design Solution Brainstorming Selection Criteria Concept Generation Pugh Chart Final System Selection Concept Feasibility Updated Project Plan System Architecture Risk Assessment
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PROBLEM STATEMENT
The goal of this project is to design, build, and reliably test an unpowered, human-controlled tethered glider specifically for use as an Airborne Wind Turbine system (AWT).
250m
100m
100m
250m10/2/2014
CUSTOMER NEEDS
Customer Need # Importance DescriptionCN1 9 Tethered glider system (with electric prop assist for launching) that
demonstrates at least 3 minutes of continuous circular flight path with taunt tether.
CN2 1 Clean appearanceCN3 9 Human controlled planeCN4 3 No special flight skill requiredCN5 9 Use existing base station designCN6 9 Tether tension is measured and recorded during flightsCN7 9 Tether direction is measured and recorded during flightsCN8 9 Videos with accompanying data files of all flight tests (even ones that don’t
work)CN9 9 Able to survive crashes with minor repairs (short downtime)
CN10 9 Replaceable PartsCN11 3 Maintenance GuideCN12 9 Design a robust glider which meets the above repair requirements and can
be piloted in the cyclical path.
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ENGINEERING REQUIREMENTS
10/2/2014
Rqmt. # Importance Type Source Engr. Requirement (metric) Unit of Measure Marginal Value Ideal Value Comments/Status Test (Verification)
S1 9 Aero CN1 Drag Coefficient -- 0.2 0.05 Calculation & XLFR5
S2 9 Aero CN1 Lift Coefficient -- 0.7 1 Calculation & XLFR5
S3 3 Aero CN1 Wingspan ft 3.3 3 Customer Constraint Tape Measure
S4 3 Aero CN4 Cooper-Harper Rating -- 3 1 Subjective
S5 3 Aero CN3 Flight Stability Binary Marginal Complete Static Stability Criteria Calulation & Flight Testing
S6 3 Aero CN11 Profile of Surface for Airfoil Manufacturing in 0.1 0.05 GD&T ASTM Standard
S7 9 Aero CN1 Efficiency of Wing - 0.82 0.9 Calculation
S8 1 Aero CN1 Fixed Angle of Attack deg 0 3 Protractor
S9 9 Electrical CN7 Horizontal Potentiometer Recording Binary Marginal Complete Capability Exists (P14462) LabVIEW
S10 9 Electrical CN7 Vertical Potentiometer Recording Binary Marginal Complete Capability Exists (P14462) LabVIEW
S11 9 Electrical CN1 Electronics Weight lbs 0.484 0.4 Motor not included Scale
S12 9 Financial CN1 Initial Cost $ 250 200 BOM
S13 3 Financial CN10 Repair Cost $ 100 50 BOM
S14 9 Mechanical CN6 Tether Tension lbs 5 23 Capability Exists (P14462) LabVIEW
S15 9 Mechanical CN1 Mechanical Weight lbs 4 3 Scale
S16 9 Mechanical CN1 Service Ceiling ft 75 100 FAA Regulation LabVIEW
S17 3 Mechanical CN1 Flight Path Diameter ft 25 50 LabVIEW
S18 9 Mechanical CN1 Maximum Glider Speed mph 30 45 LabVIEW
S19 3 Mechanical CN1 Fuselage Cross Sectional Area in2 20 16 Caliper
S20 9 Mechanical CN9 Fuselage Material Tensile Strength psi CF is ideal material MatWeb Lookup
S21 9 Mechanical CN9 Wing Material Tensile Strength psi Foam Mat'l Comparison MatWeb Lookup
S22 3 Time CN9 Repair Downtime hour 24 1 Stopwatch
S23 3 Time CN8 Time Between Flights min 30 5 Stopwatch
S24 3 Time CN4 Training Flight Hours hour 12 1 Training Documetation Stopwatch
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ENGINEERING REQUIREMENTS ADDITIONS
10/2/2014
Rqmt. # Importance Type Source Engr. Requirement (metric) Unit of Measure Marginal Value Ideal Value Comments/Status Test (Verification)
S7 9 Aero CN1 Efficiency of Wing - 0.82 0.9 Calculation
S8 1 Aero CN1 Fixed Angle of Attack deg 0 3 Protractor
S11 9 Electrical CN1 Electronics Weight lbs 0.484 0.4 Motor not included Scale
S12 9 Financial CN1 Initial Cost $ 250 200 BOM
S15 9 Mechanical CN1 Mechanical Weight lbs 4 3 Scale
S19 3 Mechanical CN1 Fuselage Cross Sectional Area in2 20 16 Caliper
S20 9 Mechanical CN9 Fuselage Material Tensile Strength psi CF is ideal material MatWeb Lookup
S21 9 Mechanical CN9 Wing Material Tensile Strength psi Foam Mat'l Comparison MatWeb Lookup
S22 3 Time CN9 Repair Downtime hour 24 1 Stopwatch
S23 3 Time CN8 Time Between Flights min 30 5 Stopwatch
S24 3 Time CN4 Training Flight Hours hour 12 1 Training Documetation Stopwatch
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GLIDER PURCHASE
UMX Radian BNF
For use as Practice Tethered Glider
Onboard Electronics Included
Folding Prop
Purchased from E-Flite via Amazon $89.99 +ship
Radio from P14462 (Professor Kolodziej) Futaba 6EX-PCM
Shipping ETA 10/1/2014
10/2/2014
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GLIDER PURCHASE
10/2/2014
Wingspan: 28.7 in (730mm)Overall Length: 16.5 in (418mm)Flying Weight: 1.50 oz (43 g)Motor Size: 8.5mm coreless brushed motorRadio: 4+ channel transmitter required
CG (center of gravity): 1.22 in (31mm) back from the leading edge of wing at wing root
Recommended Battery: 1S 3.7V 150mAh 25C LiPoFlaps: NoApprox. Flying Duration: 8-10 minutesCharger: 1S 300mA LiPo USB ChargerAssembly Time: Less than 1 HourAssembly Required: Yes
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AERO CLUB FLIGHT FAMILIARIZATION VIDEO
10/2/2014
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AGENDA
Background Problem Statement Customer Needs Engineering Requirements Week 3 action item review
10/2/2014
System Analysis Functional Decomposition (5 min) Areas of Design (3 min) Solution Brainstorming Selection Criteria Concept Generation Pugh Chart Final System Selection Concept Feasibility Updated Project Plan System Architecture Risk Assessment
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FUNCTIONAL DECOMPOSITION
10/2/2014
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FUNCTIONAL DECOMPOSITION
10/2/2014
Reach Desired Altitude
Take-Off Method Engage Tether
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FUNCTIONAL DECOMPOSITION
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Sustain Tethered Flight
Flight Path
Maintain Peak Altitude Cyclical Path
Regulate Tension
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FUNCTIONAL DECOMPOSITION
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Repeatable Flight
Provide Soft Landing Easily Replaceable Parts
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FUNCTIONAL DECOMPOSITION
10/2/2014
Record Data
Respond to on Board Feedback
Integrate with Base Station DAQ Capture Video
Record Angle Record TensionRecord length
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FUNCTIONAL DECOMPOSITION VS.AREAS OF DESIGN
10/2/2014
Areas of DesignTake Off Method
Engage Tether
Maintain Peak Altitude
Maintain
Cyclical Path
Regulate
Tension
Soft Landing
Easily Replace
able Parts
Respond to
feedback
Record Angle
Record Length
Record Tension
Capture Video
Fuselage x x x x Wings x x x x
Horizantal Tail x x Fuselage Material x x
Wing & Tail Material x x On-Board Electronics (Control
Feedback) x x x Take-Off Method x
Tether-to-Plane Connection x x x x x Propeller Location x
Non-Destructively Achieve Tether Tension x x x
Flight Path x x Non-Destructive Landing x
Base Station Data Collection Program* x x x x
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AGENDA
Background Problem Statement Customer Needs Engineering Requirements Week 3 action item review
10/2/2014
System Analysis Function Decomposition Areas of Design Solution Brainstorming (2 min) Selection Criteria (2 min) Concept Generation (2 min) Pugh Chart (5 min) Final System Selection Concept Feasibility Updated Project Plan System Architecture Risk Assessment
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BENCHMARKING
Benchmarking Table Ampyx
Wing DesignPositive dihedral, semi elliptical wing, high fixed angle of attack, flaps
Tail Design Large primary T-shaped rudder with small elevatorsFuselage Design Mildly Aerodynamic/Box Fuselage with Protruding Pitot TubeTakeoff Mechanical-Electrical winch systemLanding Lands on underside of fuselage and wingsMaintaining Tension Constant reeling in and out of figure 8 patternTether Length (m) 300-600 metersAverage Kw Creation 15kW
10/2/2014
*Image from Ampyx Power
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SOLUTION BRAINSTORMING (PT.1)
10/2/2014
Fuselage WingsHorizontal
TailFuselage Material
Wing/Tail Material
On-Board Electronics
Take-Off Method
Flying Wing Swept BackCanard EPP EPP
Wireless Transmission
Rocket Engine
Rod Type Swept ForwardRear Tail
ROHACELL Foam
ROHACELL FoamIn-Flight Data
RecorderCompressed Air
CylindersFootball Shaped High Dihedral
H-shape "Other" Foam "Other" Foam With Software Winch
Cylindrical Shape Low Dihedral V-Shape Carbon Fiber Carbon Fiber Without Software Hydraulic Cylinders
Tear-Drop Shape Oblique SweepInverted V-
ShapePlastic Coating Plastic Coating Spring Loaded
Box Frame "Typical" Blended Wing
"Typical" Shape
Monocoat Monocoat Throw Glider
Lifting Body Other Coating Other Coating Balloon Launch
Linear Chord
Variation Fiberglass Fiberglass Kite-Run Launch
Elliptical Chord
Variation Aluminum Aluminum Tow with Truck
Winglets Plastic Plastic VTOL
Bi-Wing Wood Wood
Tow with RC plane assistance
X-Wing Titanium Titanium Drop from Tall Tower Mid Placement Magnetic Rail Gun High Placement Propeller Low Placement Powered Wheels Dragon Scales Bottle Rockets Helicopter Propeller
Bend Tree and Slingshot
Catapult/ Trebuchet Hot Air Balloon Diet Coke and Mentos Zip-line System
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SOLUTION BRAINSTORMING (PT.2)
Tether-to-Plane Connection
Propeller Location
Non-Destructively Achieve Tether Tension
Flight PathNon-Destructive Landing Method
3-Point Bridle Front Hand Spool Horizontal Circle Parachute
2-Point Bridle Middle Automated SpoolOffset Vertical
CircleLanding Wheels
1-Point Fixed Bridle Back On Board Spool Figure 8 Smooth Bottom
1-Point SliderAbove
CenterlineSpring Decellerator Mobius Strip
Separate Tethered Balloon
Ball-in-SocketBelow
CenterlineConstant Force Spring Two Tether Ellipse Reverse Rockets
Set Screw Nothing (Jerk at Tension) KiteGen Flight Path Tripod
3-Point Chuck Spring on Base StationRoller Coaster Rail
TrackInflatable Stunt Pad
1 Tether per Control Surface
Lasso Flight Path Corn Field
Feedback Triggered Rocket
Decellerator Skis
Kill Propeller Power Gas Inflated Balloon
Open Cargo Bay and Drop Line at
Altitude Air Bags/ Mars Rover
Tether is a Constant Force Spring Quadcopter with Drag
Net
Velcro End of Tether to Release at
Tension
Porous Net Raised Above Ground
Two Tethers Which Trade Off Slack Reverse Zipline
10/2/2014
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SELECTION CRITERIA
10/2/2014
Simplicity & Effectiveness of Wing Design
Initial Cost
Replacement Part Cost
Weight
Durability
Ease of Manufacturing
Safe Landing
Development Time
Simplicity of Take-Off Method
Tether Stress on Plane
Tether Impulse Mitigation
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CONCEPT GENERATION
Area of Design Devin Maginn Kennedy Zebert Carl
Fuselage Design Football Shape Tear Shape Cylindrical Shape CylindricalBox type with nose cone
Wing DesignMid, High Dihedral, linear taper
Elliptical Wing/ low mount, Asymmetrical Dihedral
Linear Taper/Low Dihedral/Flaps
Flush transition from fuselage to wing/ winglets
High dihedral/ linear taper
Horizontal Tail DesignH shapeLow, Asymmetrical Dihedral Rear Tail/Normal Shape Rear Tail Rear Tail/ Normal
Fuselage Material WoodFoam/ Integrate with Fuse Other Foam/Monocoat EPP with CF rod support Carbon-Fibre
Wing/Tail Material Foam Foam with Monocoat Other Foam/Monocoat EPP or better with Monocoat Foam
On-Board Electronics Yes YesIn-Flight Data Recorder with Software
In-Flight Data Recorder with Software Yes
Plane Take-Off Method Man-powered winch
Propeller with hand launch Prop with hand launch Prop with winch launch Propeller hand launch
Plane-to-Tether Connection
Spool on Plane/ One Point
One Point/Ball and Socket Joint
One Point/Ball and Socket Joint
One Point/Ball and Socket Joint One Point Spool
Prop Location2 Mid Wing Mounted Props Nose Middle Middle (on top of fuselage) Middle
Non-Destructively Achieve Tether Tension
Spool on Board Spring Behind Base hand spool hand spool On-Board Spool
Flight Path Infinity Offset Vertical circle Offset vertical circle Infinity shape Offset Vertical CircleNon-Destructive Landing
Protruding Rod/ Smooth Bottom Parachute Deployment Smooth Bottom Smooth Bottom
Land on Airframe "Smooth"
10/2/2014
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PUGH CHART
10/2/2014
Selection Criteria Maginn Zebert Devin Kennedy Carl Datum (P14462 Bought Plane)Simplicity/Effectiveness of Wing Design + + + + +
Datum
Initial Cost - - - - -Replacement Part Cost + + + + +
Weight - - - - -Durability + + - + +
Ease of Manufacturing - - - - -Safe Landing + + + + +
Develop Time - - - - -Repair Downtime + + + + +
Simplicity of Take-Off Method s - - s sTether Stress on Plane * s s s s s
Tether Impulse Mitigation + s + s +Sum +'s 6 5 5 5 6 Sum -'s 4 5 6 4 4 Sum s's 2 2 1 3 2 Score 2 0 -1 1 2
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PUGH CHART
10/2/2014
Selection Criteria Maginn Zebert Devin Kennedy Carl Datum (P14462 Bought Plane)Simplicity/Effectiveness of Wing Design + - - s
Datum
-Initial Cost + + + + +
Replacement Part Cost + + + + -Weight - + - + +
Durability + - - - -Ease of Manufacturing - s s s +
Safe Landing + s + s -Develop Time - s - + +
Repair Downtime - - - + -Simplicity of Take-Off Method s - - s s
Tether Stress on Plane * - - s - sTether Impulse Mitigation - - s - -
Sum +'s 5 3 3 5 4Sum -'s 6 6 6 3 6Sum s's 1 3 3 4 2
k -1 -3 -3 2 0 -2
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AGENDA
Background Problem Statement Customer Needs Engineering Requirements Week 3 action item review
10/2/2014
System Analysis Function Decomposition Areas of Design Solution Brainstorming Selection Criteria Concept Generation Pugh Chart Final System Selection (5 min) Concept Feasibility (15 min) Updated Project Plan System Architecture Risk Assessment
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FINAL SYSTEM SELECTION
10/2/2014
Areas of Design Final SystemFuselage Design Aerodynamically Optimized Rectangular Volume
Wing Design Linear Taper, Fixed Angle of Attack, Dihedral, Flaps
Horizontal Tail Design H-Shaped Tail
Fuselage Material Foam
Wing/Tail Material Carbon Fiber Strip Leading Edge, Foam with Coating
On-Board Electronics (Control Feedback) In-Flight Data Recorder with Software
Plane Take-Off Method Propeller hand launch
Plane-to-Tether Connection One Point/Ball and Socket Joint
Prop Location Nose Cone with folding Prop
Non-Destructively Achieve Tether Tension Hand Spool
Flight Path Offset Vertical Circle
Non-Destructive Landing Land on Airframe "Smooth"
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FINAL SYSTEM SELECTION SKETCH
10/2/2014
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CONCEPT FEASIBILITY - FLAP ANALYSIS
10/2/2014
(1)
(2)
(3)
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CONCEPT FEASIBILITY - FLAP ANALYSIS
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CONCEPT FEASIBILITY - FLAP ANALYSIS
10/2/2014
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CONCEPT FEASIBILITY-WINCH SYSTEM
Means of takeoff since propeller alone is insufficient Pros:
System has off board source of power Cons:
Mechanical-Electrical system is expensive
Alternative Method-Man Powered Pros:
More affordable Cons:
Must exert energy Is it feasible?
Yes! The method is called a Towline Launch.
10/2/2014
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FEASIBILITY STUDY: FOAM MATERIAL
71 Hero 110 Hero 200 Hero EPP-20 EPP-60 EPP-90 EPP-150 EPP-225
Density kg/m3 75 110 205 20 60 90 150 225Tensile Strength MPa 4.10 6.30 12.30 0.26 0.62 0.97 1.37 1.51Tensile Modulus MPa 123.00 189.00 389.00 - - - - -Elongation at Break % 9.50 9.90 10.80 15 14 12 11 9Compressive Strength MPa 1.10 2.50 7.10 0.31 1.07 2.08 5.80 13.50Compressive Modulus MPa 48.00 83.00 180.00 - - - - -Shear Strength MPa 1.30 2.30 5.20 - - - - -Shear Modulus MPa 28.00 50.00 109.00 - - - - -Max Shear Strain % 7.20 7.20 7.20 - - - - -Tear Strength kN/m - - - 1.74 3.25 4.35 5.77 7.33Flexural Strength MPa - - - 0.21 0.72 1.16 1.9 2.95
ROHACELL Expanded PolypropyleneUnitTest Method
10/2/2014
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CONCEPT FEASIBILITY – FOLDING PROPELLER
10/2/2014
Benefit:• Less drag in unpowered flight• More durable in nose first crash• Interfaces with normal RC components
Feasibility Test Plan:1. Test Flight with purchased glider
Due by:1. Week 9
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CONCEPT FEASIBILITY – INFINITY FLIGHT PATH
10/2/2014
*Image from Ampyx Power
Evaluate:• Is this an easier flight path to maintain
Feasibility Test Plan:1. Test Flight with purchased glider2. Test Flight with tethered purchased
gliderDue by:1. Week 92. Week 12
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CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
10/2/2014
Definition of Dihedral: The angle between a wing and pitch axis
Dihedral Effect Definition: Amount of roll moment produced per degree of sideslip Also influenced by wing sweep, vertical CG
Benefits: Higher dihedral angles generate higher roll moments Stabilizes Plane against crosswinds
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CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
10/2/2014
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CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
10/2/2014
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CONCEPT FEASIBILITY – DIHEDRAL ANALYSIS
10/2/2014
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AGENDA
Background Underlying Mission Problem Statement & Deliverables Customer Needs & Engineering Requirements Week 3 action item review
10/2/2014
System Analysis Functional Decomposition Areas of Design Solution Brainstorming Selection Criteria Concept Generation Pugh Chart Final System Selection Concept Feasibility Test Plan Updated Project Plan (2 min) System Architecture (2 min) Risk Assessment (2 min)
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UPDATED PROJECT PLAN
SYST
EM DES
IGN REV
IEW
SUBSY
STEM
S DES
IGN REVIEW
DETAILE
D DES
IGN REVIEW
FINAL D
DR
Deliverables Deliverable Stage Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11Computer Simulator 1 1 1 1Aero Team's Trainer 1 1 1 1
1 1 1 1
1 1
1 1
Revise and Refine 1 1Concept Generation 1 1Critical Tech Analysis 1 1
Morph Chart Framework 1 1Alternative List 1 1Concept Selection 1 1Assess CapabilitiesRevisit Requirements
Systems Design Preperation
Funtiaonl Decomposition
Benchmark Existing RC Plane Parts
Existing Systems Benchmarking Table
Edge Site Upkeep and Review
Flight Experience
SYST
EM DESIG
N REVIEW
SUBSY
STEM
S DES
IGN REVIEW
DETAILE
D DESIGN REVIEW
FINAL D
DR
Section Deliverables Deliverable Stage Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15Computer Simulator 1 1 1 1 1Aero Team's Trainer 1 1 1 1 1 1
1 1 1 1 1 1
1 1
1 1
Revise and Refine 1 1Concept Generation 1 1Critical Tech Analysis 1 1
Morph Chart Framework 1 1Alternative List 1 1Concept Selection 1 1Assess CapabilitiesRevisit Requirements
Elevator Speech 1 1Feasbility Posters 1 1Invite SDR Attendees 1 1Solidify SD (see below) 1 1
SDR Action Items 1 1Test Plan 1 1Peer Reviews 1 1 1 1 1
Critical Interfaces 1 1Specs 1 1Sub- Decomposition 1 1Proof of Concept 1 1
Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1
Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1
Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1Preliminary Design 1 1Final Design 1 1 1
Preliminary Benchmark 1 1Final Code 1 1 1Preliminary Benchmark 1 1Final Code 1 1 1Preliminary Benchmark 1 1Final Code 1 1 1
List 1 1 1
MSD Project Process
Subsystem Design
Post SDR
Sytem Design
Systems Design Preperation
Funtiaonl Decomposition
Benchmark Existing RC Plane Parts
Existing Systems Benchmarking Table
Edge Site Upkeep and Review
Flight Experience
Wing Design
Aero and Structual Design
Controls
Bridal System
Simulation Code
Fuselage Design
On Plane Hardware
Tail Design
Propeller Design
Rudder Design
Structural Integrity
Control Surfaces
Electric Motor
Speed Controler
Linear Acuator Controls
Micro Controler Design
RC Design
Controls Algorithm
Maintenance Documentation
Tether Material
Base System Integration
Kinematic Simulation (MATLAB)
Aerodynamic Simulation (CFD)
Structual Analysis (ANSIS)
Replaceable Parts List
10/2/2014
SYSTEM ARCHITECTURE
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Glider Fuselage
Base Station
Wings
Ailerons
Horizontal Tail
Vertical Tail
RudderElevators
On-Board Feedback System
TetherRemote Control
On Board Control
Electronics
Propeller
Motor
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RISK ASSESSMENT
10/2/2014
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RISK ASSESSMENT (CONT.)
10/2/2014
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SOURCES
10/2/2014
Feasibility Study: Foam Material http://
www.rohacell.com/sites/dc/Downloadcenter/Evonik/Product/ROHACELL/product-information/ROHACELL%20HERO%20Product%20Information.pdf
http://www.sonoco.com/UserFiles/sonoco/Documents/Tegrant%20EPP%20Design%20Guide%20April%202012.pdf
http://en.wikipedia.org/wiki/Dihedral_(aeronautics)