Auburn University USLI

Auburn University USLIFRR Presentation

AirframeJonathan Leonhardt

Vehicle Dimensions• Total Length of 75.125 inches• Inner Diameter of 5 inches• Outer Diameter of 5.5 inches• Estimated mass of 31.3 ounces

Clipped Delta• Easy to manufacture• Proven design• Performs well during sub sonic flight

Material selection• Carbon Fiber▫ High strength to weight

• HIPS 3D printed plastic▫ Ease of manufacturing

• Braided carbon fiber▫ Lighter than a solid carbon fiber structure

Braided Tubes• Body tube support structure• Motor tube structure• Manufactured at Auburn University

Stability Margin• Static stability margin of 2.32 Calibers• CG is 43.25 inches from nose cone• CP is 57.16 inches from nose cone

Section Mass (lb) Percentage

Structure 10.8 34.5%

Recovery 4.51 14.4%

Grid Fins 3.00 9.58%

Electronics 1.52 4.85%

Motor 7.90 25.24%

Ballast 5.00 15.97

Total 31.3 100%

Motor Selection• Motor has been changed to Loki L-1482

Predictions with Loki L - 1482• Simulated altitude of 5367 feet (AGL)• Thrust to weight ratio is 11:1• Provides rail exit velocity 44.3 ft/s

Motor Specifications

Manufacturer Loki Aerotech

Motor Designation L1482 L1520T

Diameter 2.95 in 2.95 in

Length 19.6 in 20.9 in

Impulse 3882 N-s 3769

Total Motor Weight 7.78 lbs 8 lbs

Propellant Weight 4.05 lbs 3.925

Average Thrust 339 lbs 340 lbs

Maximum Thrust 407 lbs 382 lbs

Burn Time 2.6 s 2.49 s

Requirements Verification Summary(Launch Vehicle)

• Subscale launch and successful recovery –Completed

• Full scale launch and successful recovery –Incomplete

Full Scale Flight Tests• Flight 1 : Failure (Altitude and recovery failure)• Flight 2 : Failure (Motor CATO)• Flight 3 : Failure (PLF Failure)• Flight 4 : Failure (Motor CATO)• Flight 5 : Launch April 2nd , 2016

RecoveryAdam Wolinski

Recovery Overview

Parachutes• Three parachutes required▫ Drogue – Circular – 22.11 inches▫ Payload Main – Hemispherical – 52.56 inches▫ Booster Main – Hemispherical – 39.84 inches

• Both mains will have a spill hole

Parachutes• Construction▫ Gores

• Ripstop nylon▫ Tear resistant weaving

ParachutesPayload Main deployed with Tender Descender by Tinder Rocketry

Attachment Hardware• Nylon Slotted Pan Head Machine Screws• Steel U-Bolts• Quick Links

Shock Cord• 1 inch tubular nylon• Excellent tensile strength• Low weight• The Auburn team has worked

with this material before

Electronics – Altimeters • Two Altimeters▫ Altus Metrum Telemega▫ Altus Metrum Telemetrum

• Taoglas FXP240 433 MHz ISM Antenna

CO2 Ejection System• Increased Safety• Better reliability at higher altitudes• Lowered risk of equipment and parachute damage

CO2 Ejection System• Redesigned Auburn’s Custom System• Three 12g cartridges for redundancy

Payload FairingLindsey Batte

PLF Final Design Overview• Purpose: ▫ Deploy Drogue/Main

Parachute• Design▫ Elliptical Design▫ 13 Inches Tall

▫ 18

in. Wall Thickness

PLF Component Overview• Vertical Sheer Pin Brackets

(Next Slide): ▫ Prevent premature separation

during flight ▫ Holds 4 vertical sheer pins

• Charge Bay:▫ Contains black powder charge

that will induce separation ▫ Location chosen to produce

largest moment▫ Lined with Fiberglass

• Ribs ▫ Ensure structural integrity of

the fairings▫ Aerodynamic Seal:

▫ Paraffin wax seal along all seams

Shear Bracket

PLF: Partial Deployment• Side A: ▫ Lip (inner/outer) Configuration on next slide

▫ Plugged half of the Charge Bay

• Side B:▫ Recessed▫ Open half of the Charge Bay▫ Outer Lip Contoured▫ Wax Seal

PLF Design Changes• Inner Lip (0.25 in) ~

Unchanged• Outer Lip (0.5) ~ Doubled • 4 Shear Brackets ~ +2• Kevlar Charge Chamber • 0.4 grams of BP ~ +0.1 grams• Wax to make the PLF air tight

PLF Design EvolutionPLF Version 1• 4 Horizontal

10-lb sheer pins

• Inner seal only

• 0.3 grams of black powder

PLF Version 2• 2 10-lb

vertical sheer pins

• Inner seal• 0.5-in outer

seal • 0.3 grams of

black powder

• 2 10-lb vertical sheer pins

• 2 25-lb vertical sheet pins

• Inner seal

• 1.0-in outer seal

• Paraffin wax seal on all seams

• 0.4 grams of black powder

PLF Version 3

PLF Testing: Charge Bay Strength Test• Test Article: ▫ Charge Bay

• Reason:▫ Determine the “Breaking

point” of the charge chamber structure

▫ Conclusion:▫ The charge bay will not be

damaged even when filled to capacity

PLF Testing: Ground Testing• Test Articles:

▫ PLF v.1, PLF v.2, PLF v.3• Reason:

▫ Ensure that the charge will effectively separate the fairing halves.

▫ Conclusion▫ Each version of the PLF

was able to successfully deploy on the ground.

PLF Testing: Full Scale Testing• Test: Aquila I• Test Article:

▫ Static Full-Scale nose cone

• Results:▫ The rocket remained

stable throughout the flight

▫ Conclusion▫ The aerodynamic design

of the PLF performs well in transonic conditions.

PLF Testing: Full Scale Testing• Test: Aquila II and

Aquila IV• Test Article: ▫ PLF v.1, PLF v.3

• Results:▫ Motor CATO

▫ Conclusion▫ None

PLF Testing: Full Scale Testing• Test: Aquila III• Test Article:

▫ PLF v.2• Results:

▫ PLF deployed prematurely at Mach 0.6.

▫ Conclusion▫ Air broke through the

outer/inner seals at the stagnation point forcing the fairings to deploy.

▫ Need better aerodynamic seal

Aerodynamic Analysis Payload Gabriel Smith

OverviewMission:• To collect data on aerodynamic protuberances• Secondary mission:▫ Assist the rocket to the one mile height

requirement through aerodynamic braking

Wall Armed Fin-Lattice Elevator(WAFLE)• The WAFLE is the optimal

system designed to accomplish both missions

• Subsystems:• Grid fins• Arduino• Servos• 10-DOF IMU• RF Tracker• Outer Fairing

Height 8.85 in

Mass 2.5275 lb.

Diameter (inner/outer) 5/5.125 in

WAFLE Deployment

Grid Fin• The grid fin is the subsystem that all aerodynamic analysis will be performed on.

• Grid fin will act as a drag control surface

• 3D manufactured with HIPS

Length 5.91 in

Span 2 in

Height 0.77 in

Arduino• Arduino Uno will control the

WAFLE subsystems• Control calculations and

predict height of the rocket through acceleration input.

Operating/ Input Voltage

(V)

Analog I/O Digital I/O

5 / 7-12 6 / 0 14 / 6

Servos• Savox SV-1270TG Servo will

control the actuation of the grid fin.

• Precise angles under a flight loads can be achieved with this servo.

• Located on the exterior of the airframe, under the external fairing

Torque

(kg/cm)Size (cm) Weight (g)

35.07 4.0 x 2 x 3.7 56

10-DOF IMU• 10 DOF IMU Breakout records

acceleration and rotation in the x,y,and z axis as well as barometric pressure and temperature.

• Primary sensor for the WAFLE sensor

Operating Voltage (V)

AccerationTolerance (g)

Altitude Tolerance (ft)

3 - 5 ± 16 ± 3

RF Tracker• RC-HP Transmitter will act as

the tracking for the WAFLE system and the booster section.

• A CR2032 battery with a life span of 1 week

• Transmitting frequency of 222.450 MHz

Outer fairing• Aerodynamic fairing that

reduces aerodynamic loading on servos and grid fin base.

• Made from filament wound carbon fiber.

Fairing Span 2 in

Fairing Length 4.1 in

Fairing Height 1 in

Planned Test and Simulations• Simulations▫ Computational Fluid

Dynamics (CFD)▫ SolidWorks Flow ▫ Fortran- Flight and Dynamic

model▫ Drag Profile

• Test▫ Aerodynamic Load Testing▫ Vortex Shedding Testing▫ 1:5 Scale Test▫ 3:5 Scale Test ▫ Full Scale Test

Simulation ResultsVariable Value

Drag Estimate of Fins (at Max Velocity, 45 degrees)

53.16 lbf

Drag Estimate of Fins(at Max Velocity, 90 degrees)

13.45 lbf

Drag Estimate of Rocket (at Max Velocity)

96.94 lbf

Drag Estimate of Rocket and Fins (at Max Velocity, 45 degrees)

150.11 lbf

Drag Estimate of Rocket and Fins (at Max Velocity, 90 degrees)

110.39 lbf

Max Acceleration (at Max Velocity with Fins, 45

degrees)-185.19 ft/s^2

Max Acceleration (at Max Velocity with Fins, 90

degrees)-136.19 ft/s^2

SafetyAustin Phillips

Educational OutreachNoel Cervantes

Project OverviewCassandra Seelbach