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Progress Report. Order of Presentation. David – Intro and Fall Review Matt – Testing and Summary of Changes Josiah – Details on New Design Josh – Electrical Hardware Ona – Electrical Software / Optimization TJ – Progress Summary / Future Work. Outline. Summary – Fall (David)
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Order of Presentation • David – Intro and Fall Review • Matt – Testing and Summary of Changes • Josiah – Details on New Design • Josh – Electrical Hardware • Ona – Electrical Software / Optimization • TJ – 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 Overview • Develop a UAV which will satisfy the AIAA Design/Build/Fly Competition mission profile. • Competition Details • Location: Tucson, AZ • Date: April 15-17, 2011 • Major requirements: • Hand launched • Fixed wing • Electric powered (NiCad or NiMH batteries) • Propeller driven • Must be contain within a carry on bag • Max 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
Testing • Manufacturer Motor Specifications • Max Static Thrust: 42.4 oz (2.65 lb.) • Able to propel 5 lb. aircraft • Static Thrust • GLX Force Sensor • Various Propellers / Throttle Settings • Graph (12x8, 9x7.5, etc) • Conclusions • Thrust may be insufficient for hand launch at initial desired weight of 5lbs • Need to reduce the size and weight of system • Don’t want to increase battery size / weight • Motor is already best option
Payload Configuration • Reduced to two rows side by side • Less required storage space • Less required structure
New Dimensions • Smaller Design • Lighter • Less drag • Less energy consumption Old Design New Design 4.5” 3” 23” 30”
Bulkhead Selection • Provides stiffness, toughness, and ease of fabrication • Carbon fiber/Balsa Wood • Joined via thin circular CFRP tie rods
Landing Platform – Friction Contact • Advantages • Ergonomic hand launch • Less drag • Disadvantages • Higher potential for damage • Propeller interference with ground
Landing Platform Low Friction Ground Contacts • Requirements • Leading ground contacts must be low friction • Rear contact must be high friction • All contact materials must be abrasion resistant • Our approach • Carbon Fiber/Kevlar hybrid composite • Teflon/low friction coating for front ground contacts High Friction Ground Contact
Wing Connections – Friction Fit • Slides tightly into position • Quick and easy assembly • Light weight • Few components to break
Mission Model #) Phase (Throttle Setting) • Hand Launch (100%) • Acceleration (100%) • Turn 1 (90%) • Cruise (75%) • 5) 360 Degree Loop (90%) • Cruise (75%) • Turn 2 (90%) • Landing (50%)
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 & 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
Block Diagram Electronics & Controls
Aircraft Optimization Inputs Analysis Optimization Optimal Parameters Optimized? Yes No Lift Coefficient Drag Coefficient Empty Weight Aircraft Dimensions Wind Speed Payload Size / Weight Propeller Size Motor Properties Gear Box Battery Properties Reference Payload Reference Laps Propulsion Power Aerodynamics Structures Performance Mission Score Overall Score Aircraft Dimensions Payload Size / Weight Propeller Size Motor Properties Gear Box Battery Properties Top Speed Performance
Payload Configuration • Image of new golf ball arrangement • Smaller size (width and height) • Better for gripping • Less drag • Easier 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
HPMI • Image of manufactured component • Learned process to fabricate composites • Honeycomb-core no good • Too heavy if filled with resin • Requires different technique (wet layup) • Permitted access to HPMI facilities • Friday 01/28 @ 8:30am • Manufacture more components for testing • Begin to fabricate wings, fuselage, other parts
Preliminary Fabrication • Nomex 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 Progress • Fabrication of First Prototype • Mission and Performance Analysis Code • Power System Simulink Simulation • Control System Programming • CFD of Prototype • Report Compilation
Future Work • Control System Testing • Flight Testing • Design Optimization • Finalize Report