order of presentation david – intro and fall review matt – testing and summary of changes josiah...
TRANSCRIPT
Order of PresentationDavid – Intro and Fall ReviewMatt – Testing and Summary of ChangesJosiah – Details on New DesignJosh – Electrical HardwareOna – Electrical Software / OptimizationTJ – Progress Summary / Future Work
Outline Summary – Fall (David)
Review of Competition (missions, specs, etc.) Old Design
Progress Report New Design (Josiah) Testing (Matt)
Static thrust Endurance Various propellers / throttle settings conclusions
Payload Configuration (Matt) New Dimensions (Josiah) Bulkhead Skeleton (Josiah) Landing Gear (Josiah) Wing Attachment (Josiah) Electronics Configuration (Josh/Ona)
Block Diagram (side-by-side) Mission Model (flow chart) (Matt) HPMI (Matt)
Future Work (TJ) Fabrication
testing CFD Finalize Mission Model
Project OverviewDevelop a UAV which will satisfy the AIAA Design/Build/Fly
Competition mission profile.Competition Details
Location: Tucson, AZDate: April 15-17, 2011
Major requirements:Hand launchedFixed wingElectric powered (NiCad or NiMH batteries)Propeller drivenMust be contain within a carry on bagMax propulsion battery of ¾ lbs.Max current draw of 20 amps
Mission Profile
Mission 1: Dash to Critical Target•4 minutes without payload to fly around course•Scoring equation:
Mission 2: Ammo Re-supply•Steel bar payload completing 3 laps around course•Scoring equation:
Mission 3: Medical supply Mission•Golf balls payload completing 3 laps around course•Scoring equation:
Fall Semester Final Design
Side
Top
New Design
Testing – Complete Setup
Testing – Propulsion System
Testing – Data Logger Interface
TestingManufacturer Motor Specifications
Max Static Thrust: 42.4 oz (2.65 lb.)Able to propel 5 lb. aircraft
Static ThrustGLX Force Sensor
Various Propellers / Throttle SettingsGraph (12x8, 9x7.5, etc)
ConclusionsThrust may be insufficient for hand launch at initial
desired weight of 5lbsNeed to reduce the size and weight of systemDon’t want to increase battery size / weightMotor is already best option
Payload Configuration
Reduced to two rows side by side
Less required storage space
Less required structure
New Dimensions
Smaller DesignLighterLess dragLess energy consumption
Old DesignNew Design
4.5”3”
30”23”
Bulkhead SelectionProvides stiffness,
toughness, and ease of fabrication
Carbon fiber/Balsa Wood
Joined via thin circular CFRP tie rods
Landing Platform – Friction Contact
AdvantagesErgonomic hand
launchLess drag
DisadvantagesHigher potential for
damagePropeller
interference with ground
Landing PlatformRequirements
Leading ground contacts must be low friction
Rear contact must be high friction
All contact materials must be abrasion resistant
Our approachCarbon Fiber/Kevlar
hybrid compositeTeflon/low friction
coating for front ground contacts
Low Friction Ground Contacts
High Friction Ground Contact
Wing Connections – Friction FitSlides tightly into
positionQuick and easy
assemblyLight weightFew components to
break
Mission Model
1) Hand Launch (100%)
2) Acceleration (100%)
3) Turn 1 (90%)
4) Cruise (75%)
5) 360 Degree Loop (90%)
6) Cruise (75%)
7) Turn 2 (90%)
8) Landing (50%)
#) Phase (Throttle Setting)
Electronics - Hardware Propulsion Batteries: Elite
1500 mAh (10 Cell NiMH) 4.5 minutes battery life
(theoretical) 12V; 20A Avg. Current Draw
5.25 minutes battery life (tested) 13.5V; 16A Avg. Current Draw May need to increase Capacity
Servo Batteries 750 mAh (5 Cell NiMH) Servo Controller draws
minimal current Battery Lifetime yet to be
determined Receiver added to Servo
Battery Pack to maximize the lifetime for Propulsion Battery Pack.
Electrical/Electromechanical Components DX6 Transmitter/Receiver Himax 2025 Brushless Motor Castle Creations Phoenix
25A ESC Recommended for motor
Micro Maestro 6 Ch USB Servo Controller Supports 4 Servos / 1 Gyro Programmable
Dual Axis Gyroscope (Pitch and Roll) May or may not be used Can fight with experienced
pilots
Electronics - Hardware
Electronics & Controls Main selections- DX6i 6-channel transmitter (Spektrum)- AR6200 6-channel receiver (Spektrum)- Micro Maestro 6-Channel USB Servo Controller (Pololu)- Digital Servo D65HB (HuiDa RC International Inc) - LPR510AL Dual-Axis Gyroscope (Pololu) Safety Manuever - Kill Throttle- Roll Right- Yaw Right- Nose Up
Electronics & Controls Block Diagram
Aircraft Optimization
Lift CoefficientDrag CoefficientEmpty Weight
Aircraft DimensionsWind Speed
Payload Size / WeightPropeller Size
Motor PropertiesGear Box
Battery PropertiesReference Payload
Reference Laps
PropulsionPower
AerodynamicsStructures
Performance
Optimized?
Yes
No
Mission ScoreOverall Score
Aircraft DimensionsPayload Size / Weight
Propeller SizeMotor Properties
Gear BoxBattery Properties
Top SpeedPerformance
Inputs Analysis Optimization Optimal Parameters
Payload ConfigurationImage of new golf ball arrangementSmaller size (width and height)
Better for gripping Less dragEasier to fit into suitcase
16 golf balls (~1.6lbs)Decrease size of steel bar
P/W ~ 1.5 instead of 2.5
Maximum weight ~3lbs loaded
HPMIImage of manufactured componentLearned process to fabricate compositesHoneycomb-core no good
Too heavy if filled with resinRequires different technique (wet layup)
Permitted access to HPMI facilitiesFriday 01/28 @ 8:30am
Manufacture more components for testingBegin to fabricate wings, fuselage, other
parts
Preliminary FabricationNomex Honeycomb-Carbon Fiber
Composite Attempted Vacuum Bagging Need Different Fabrication Method (Wet Layup) Too Heavy Foam Core to Replace Honeycomb Kevlar added to bottom for landing gear
Work in ProgressFabrication of First PrototypeMission and Performance Analysis CodePower System Simulink SimulationControl System ProgrammingCFD of PrototypeReport Compilation
Future WorkControl System TestingFlight TestingDesign OptimizationFinalize Report