Vanderbilt University NASA University Student Launch Initiative

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Vanderbilt UniversityNASA University Student
Launch Initiative

• Flight Readiness Review
• Presentation

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Mission

• Our mission is to design, construct, test, launch
  and recover a rocket that travels to a mile high
  altitude which complies with the performance
  criteria laid down by USLI. The payload shall
  consist of a UAV, launched at a previously
  selected altitude, and landed separately from the
  rocket, following some remote sensing operations.
  
• We are also interested in developing a robust
  student-based program, which explores the overall
  scientific and technical issues in rocketry and
  aerial vehicle design and operation

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The Team

• Students
• Glen Bartley
• Thomas Folk
• Andrew Gould
• Nathan Grady
• Chris McMenamin
• Brandon Reed
• Will Runge
• Alex Sobey
• Greg Todd

• Advisors
• Professor Dr. A.V. Anilkumar
• Safety Officer Robin Midgett
• Army Engineer Dr. Patrick Taylor
• Rocket Enthusiasts Rodney McMillan and Russell
  Bruner

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Where We Are

• We have completed our first full size test
  launch, proven our payload deployment mechanism
  and have fabricated two uniquely designed
  prototype UAVs
• Ready for Launch Competition

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Justification of Rocket Deployment

• The rocket takes the UAV
• to its maximum altitude
• before using any battery
• life
• Range is now glide from
• starting altitude plus
• powered flight from battery
• Available area available for surveillance is
  greatly increased

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Actual Range

• Potential 3 mile ceiling for UAV and Rocket
• 101 Glide Ratio equals 30 miles of glide range
• Previous powered range of 6 miles increased since
  level flight requires less energy than climbing
  flight
• Estimated Total Range of 42 miles
• 7 TIMES GREATER RANGE OF SAME UAV DEPLOYED FROM
  ROCKET

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UAV Design History

• 2 Wing Rotation Concepts
• Split Wing Rotation
• Longer Wingspan, Sacrifice Chord Length
• Single Wing Rotation
• Larger Chord Length, Sacrifice Wingspan

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UAV Testing

• Wing Rotation Limitations
• Larger chord length yielded better flight
  characteristics
• Single wing rotation mechanism became the primary
  design
• 3 Test Gliders
• Adjustable wing position glider Determined the
  desired center of gravity of entire craft with
  respect to the quarter chord length of the wing
• Dihedral wing glider Demonstrated the static
  stability advantages of a dihedral wing
• Full weight and dimensions with control surfaces
  Concluded that the results from the previous
  gliders were applicable at full scale

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Airfoil and Wing Dimensions

• NACA Designation 6312
• Wing Span 43.5 in.
• Aspect Ratio 5.9
• Dihedral Angle 5

Max Camber Position 2.2 in.
Thickness 1 in.
Camber
Max Camber .5 in.
Cord Length 8 in.
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Pictures of Wings
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UAV Construction

• The tail plane, control, surfaces and wing use
  2mm and 4mm CoroplastTM (corrugated plastic
  sheeting).
• Fuselage is made from either 1/16 in. aluminum
  L-channel or 1/16 in. PVC
• U-channel
• Electronics consist
• Standard 8 gram servos
• HiTEC Micro 05S receiver
• BP 40A Brushless ESC Controller
• 450W Brushless Motor
• 3-Cell Li-Po Battery

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Wing Rotation Mechanism
Center Axis

• Materials
• ¾ in. Acrylic plates
• 2 springs
• Several screws, nuts,
• and bolts
• Spring driven rotation
• Acrylic Stoppers
• Locking Pin

Locking Pin Hole
Stoppers
Rotation Spring
Locking Pin
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Pictures of Current UAV Design
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Pictures of Current UAV Design
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UAV Test Film
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Rocket Design

• Static Stability Margin
• 1.5 ( same as previous test launch)

• Dimensions
• 10.125 in OD
• 14 ft. Tall
• 80 lbs (loaded)

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Rocket Assembly

• Three main components, each with its own system

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Parachute Sizes

• Drogue Deployment
• Size 4 ft.
• Descent Rate 18.4 m/s
• Main Body Section
• Size 10 ft.
• Descent Rate 5.4 m/s
• Payload Section
• Size 8 ft.
• Descent Rate 5.9 m/s

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Motor Selection and Rail Exit Velocity

• Motor Selection
• Aerotech M1939W
• Total Impulse 10240 N-s
• Prop. Weight 5300 g
• Burn Time 7 s
• Rail Exit Velocity
• 66.5 ft/s

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G-force on Rocket from M1939W Motor
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Thrust to Weight
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Rocket Airframe

• Original Airframe
• Thumper rocket kit
• Fiberglass over cardboard
• 12 feet tall
• Airframe Modifications
• Payload Bay
• Lengthened to accommodate longer UAV
• Two standard body sections fiberglassed together
• 14 feet new overall length
• Fins
• Originally Baltic birch
• Updated with carbon fiber laminate

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Carbon Fiber Fins

• In order to increase the dynamic stability of the
  rocket, the center of gravity had to be moved up
• Therefore, either weight had to be added to the
  nose thus creating dead weight or removed from
  the bottom section of the rocket.
• Solution reduce the weight of the fins by
  replacing the Baltic Birch material with Carbon
  Fiber
• The specific compressive strength of the carbon
  fiber was found to be roughly 6 times greater
  than that of the birch
• In order to preserve the center of pressure, the
  overall fin shape was not altered

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Carbon Fiber Fin Fabrication

• Carbon fiber sheet made in house
• Three layers of woven aerospace grade tri-axial
  carbon fiber cloth
• Impregnated with high temperature epoxy resin to
  withstand exhaust heat
• Air dried overnight between sheets of glass
• Baked in kiln for 18 hours to finish curing
• Over 30 weight savings and twice as strong

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Launch Pad

• Portable launch pad constructed specifically for
  the large rockets demands
• Main Parts
• 3/16 inch thick 3 ft.
• square steel blast plate
• Four foldable legs
• Adjustable feet for
• leveling
• Hinged 16 ft. 80-20
• launch rod
• Simple, heavy, effective

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Test Launch Film
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Flight Test

• Test rocket configured with short payload bay and
  ballast to simulate UAV weight
• 1.5 calibers of stability
• M1297WP motor with 5417 Ns impulse
• Calculated altitude was 3500 ft
• Actual Altitude was 3052 ft

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Deployment Avionics

• Four Perfect Flight MAWD altimeters will be used
  for deployments
• Two for the drogue and main parachutes
• Two for the UAV deployment
• Redundancy in the design minimizes chutes not
  deploying as needed
• The altimeters will be tested in a pressurized
  chamber before their use
• Previously tested Copilot altimeters were used on
  the test flight

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Ejection Charge Test

• The commercial supplier of the base rocket,
  Polecat Aerospace, suggested the use of 3 4.5
  grams of back powder for ejection charges
• The test
• Four 256 nylon screws as shear pins
• 3 grams of black powder
• The rocket was resting horizontally
• It was found that this configuration of shear
  pins and charge amount is acceptable for the
  rockets stage deployments

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Sled Payload Deployment
The weight of the nosecone can produce a torque
which turns the piston inside the payload bay
tube disrupting deployment.
Preventing this torsion in the sled would add
unnecessary weight and decrease the amount of
volume in the payload bay.
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Sabot Payload Deployment

• The UAV will be encased in two form-fitting
  pieces of foam and placed in the payload tube
• A piston at the aft end of the tube will cause
  the pressure in the chamber to increase after a 6
  gram black powder charge, ejecting the nose cone
  which will pull the UAV and its foam casing out

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Sabot Payload Deployment
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Drogue Deployment Test
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Main Deployment Test
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UAV Deployment Test
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Questions?