University Student Launch Initiative (USLI) Florida Institute of Technology April 2, 2009

1. Panther II Heavy FRR: Measurement and CFD Prediction of Liquid Slosh Behavior During Model Rocket Flight University Student Launch Initiative (USLI) Florida Institute of Technology April 2, 2009 Alex Berta, Jiten Chandiramani, Esteban Contreras, Niroshen Divitotawela, Robert Geuther, David Jarkey, Justin LaFountain, Philip Meyer, Scott Perry Dr. Hector Gutierrez, Dr. Daniel Robert Kirk, H. Greg Peebles III

2. Project Overview and Goals • Successfully compete in 2008-2009 USLI competition: Design/build/recover a model rocket to fly to one mile apogee • Perform a NASA-relevant science experiment during flight: Use rocket flight to simulate and obtain slosh behavior during low-gravity maneuvers • Acquire full 6-Degree of Freedom rocket trajectory data: Facilitate benchmarking of NASA’s Universal Control Analysis Tool (UCAT)

3. Science Experiment Motivation • Motivation: Upper-stages of rockets undergo orbital maneuvers that may lead to large propellant slosh motions which may adversely impact performance • Example: NEAR spacecraft interrupted its insertion burn when fuel reaction was larger than anticipated. Prevented NEAR from orbiting Eros and delayed mission • Example: Does new NASA Orion spacecraft need baffles? • Problem to be addressed by science experiment: Lack of experimental data to benchmark and anchor advanced computer simulations of liquid propellant slosh • Florida Tech has extensive slosh dynamics research program including ground testing and multiple experimental flights on NASA’s Low-Gravity Research Aircraft • Utilize USLI competition as opportunity to conduct NASA-relevant science experiment aimed at acquiring vital slosh dynamics data which can be shared with researchers around the world! Delta IV Heavy Rocket

4. UCAT Overview • 6 DOF trajectory modeling and analysis essential for launch approval • University and industry need to supply reliable preliminary trajectory analysis • Trajectory verified by Air Force 45th Space Wing • SPLASH: Only “low-end and affordable” 6 DOF trajectory analysis programs on market • Air Force 45th Space Wing has deemed SPLASH not adequate for preliminary safety evaluation of trajectory • Space Florida is contracting for SPLASH upgrade • SPLASH has “a long way to go before adequate” • NASA KSC Mission Analysis Group has developed 6 DOF Universal Control Analysis Tool (UCAT) • Currently used by KSC to simulate large launch vehicle dynamics, trajectory and mission profile verification • Florida Tech working with KSC to upgrade UCAT and develop generic models appropriate for university or industry use • Input of thrust stand motor data into UCAT for flight analysis • NASA KSC interested in extending UCAT use for preliminary trajectory analysis for CCAFS university or industry launch customers

5. Overall Airframe Layout • Basic layout guided by over 10 years of high powered model rocket experience at Florida Tech • Detailed Pro|Engineering CAD model developed to aid design, predict exact mass properties (Mcg, Iij matrix) and input to NASA UCAT • Overall Dimensions (L = 12.5 ft, W = 25 lb) • Materials used: • G10 Fiberglass Main and coupler tubing Bulkheads • Aluminum reinforced bulkheads Nosecone Payload Main Recovery Drogue Motor/Fins

6. Thrust Measurement • Multi-DOF motor thrust measurement and statistical sampling critical to flight performance prediction • Florida Tech has unique 6-DOF thrust stand capable of measuring thrust misalignment and motor torques • Thrust curve provided by most manufactures (e.g. Loki Research) is insufficient for accurate modeling • Nominally only provide 1 axis of thrust – neglects thrust misalignment which can be significant! • Provides no estimate for test-to-test repeatability and statistical deviations (propellant mass, nozzle manufacture and alignment, etc.) • Such limited manufacture data would be insufficient for a rocket launch from Cape Canaveral Air Force Station as mandated by US Air Force 45th Space Wing – Florida Tech has launched student built rockets from CCAFS and provided high-fidelity thrust vs. time motor data

7. 9 10 9 8 8 7 7 6 6 Thrust to Weight Ratio 5 Thrust to Weight Ratio 5 4 4 3 3 2 2 1 1 0 0 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 0 0.5 1 1.5 2 2.5 3 3.5 4 Time (s) Time (s) Thrust to Initial Weight Ratio • Thrust curve provided by Loki Research on Rocksim database for Loki L930 motor • Shows approximate weight can generate enough velocity to remain stable Thrust to Weight Ratio for maximum projected vehicle weight of 30lbs. Thrust to Weight Ratio for minimum projected vehicle weight of 25lbs.

8. Space Florida Funded Test Stand • 10,000 lb capability • Measurement of all 6 degrees of freedom using state-of-the art instrumentation • No comparable facility in the world! • Capable of obtaining thrust misalignment data to compare to industry-given data

9. Test Fire Results • Thrust data in axial direction confirms given Loki Research given data • Thrust in non-axial directions can be used for thrust misalignment calculations Rocket Motor • Average Thrust = 199 lbs • Peak Thrust = 275 lbs • Burn Time = 3.61 s • Impulse = 795.7 lb· s

10. Launch Rail Considerations • Rocket needs certain speed by end of launch rail to produce aero-forces on fins to overcome any unforeseen thrust misalignment forces thus ensuring that rocket flight is within 30 deg of nominal flight trajectory • With known solid motor thrust vs. time history, speed of rocket along rail is calculated to be ~86 ft/s. • Knowing speed of rocket provides dynamic pressure on fins, and fin area then checked to ensure adequate stabilizing force vs. thrust misalignment and wind • If necessary iterate on final fin sizing and rocket mass distribution

11. Rocket Flight Stability • Complete model parameters (payload and recovery dimensions, etc.) input into RockSim and UCAT • Static Margin: 2 • Fins sized down after thrust misalignment altered • Rocket’s estimated altitude: 5200 ft cp cg 152.25” L x 4.00” D

12. Recovery Avionics • Avionics package selected to deploy parachutes at appropriate points of flight • Avionics selected and tested: • Ozark Aerospace ARTS 2 (left) • G-Wiz Partners HCX (right) • Completely redundant system: • Each recovery stage has an extra ejection charge mortar • Each mortar is blown by two electric matches, controlled by each avionics board

13. Dual Deployment Avionics Test • Flight computers tested to ensure firing of electric matches at appropriate times • Computers tested during test flight with dummy payload to ensure successful deployment G-Wiz Pyrotecnics Computer Test

14. Ejection Charge Amount Test • ONE ejection charge mortar will have a prefabricated squib, covered with tape • Avionics section installed with shear pin and weighted • Charge remotely ignited • Test repeated with different squibs until optimal deployment achieved • Main Charge – 9g • Drogue Charge - 4g Ejection Charge Mortars Ejection Avionics Board Ejection Avionics Batteries Perfect Flight Altimeter Perfect Flight Battery

15. Parachute Sizes and Descent Rates • Extended microgravity time required for science experiment necessitates use of two parachute system • Drogue Parachute (left): • RocketMan Enterprises 4ft Pro-Experimental • Timed deployment after reaching apogee • Slows rocket to terminal velocity of 50ft/s • Main Parachute (right): • RocketMan Enterprises 12ft Standard • Deployed at altitude of 800ft. • Slows rocket to terminal velocity of 16ft/s • Kevlar shock cord attached to U-bolts at both ends of drogue and main compartments connects parachutes to rocket

16. Payload Layout/Integration IR Camera (inside tube) Focal length for camera 6 DOF Board VCR (not shown here) Batteries Slosh Tank L-Brackets • 6 DOF boards connected to top bulkhead for easy data download • Bottom L-Brackets connect to a U-Bolt that passes through the large upper bulkhead

17. Payload Sensors Single axis gyroscope Dual axis accelerometer • Two dual axial accelerometers that measure ±18g • Three single axis gyroscopes that measure ±75º/sec • Data collection rate of 1000 Hz • Collected data used to benchmark NASA UCAT

18. PIC microcontroller Mounting Holes • Electronics controlled by PIC (Programmable Interface Controller) • Data collected on EEPROM (Electrically Erasable Programmable Read-Only Memory) • Board and sensors designed to fit within 3.75” diameter tube Sensors EEPROMs

19. Dummy Payload • Same size, weight, and weight distribution as payload • Disposable • Connects to upper bulkhead in same fashion as payload • Used for Palm Bay test flight

20. Procedures • Before payload is inserted into rocket payload systems will be turned on • System is triggered before engine ignition • After 60 seconds the system stops recording • Data recovered using a USB cable attached to sensor boards

21. Triggering • Pratt Hobby’s hybrid ground launch electronics will be used to start collecting data and ignite engine • First (normally fills tank) signal will turn on video recorder and sensor boards • Second signal on separate channel will ignite engine.

22. Project Safety • Regulatory Compliance: The MSFC USLI competition safety requirements regarding ATF, DOT, EPA, FAA, OSHA, & TRA/NAR are already in place within existing Florida Tech Rocketry Program. All pyrotechnic testing has and will conform to these standards. • Material Hazard Analysis – Ongoing. • Failure Modes and Effects Analysis – Ongoing. • Motor, Vehicle & Payload testing – Ongoing.

23. Test Launch – 3/14/09 • Height of 5144 ft • Both parachutes deployed successfully • All avionics recovered safely • Booster section lost • Recovered week later • Unscrewed eyebolt problem resolved

24. Outreach • Bayside HS • Physics class • Class discussion at time TBD • Sebastian River HS • Science class • Organized through teacher Cassandra Gonyer • 2 Class discussions April 3rd • Focus on aerospace opportunities in college, careers, women in aerospace and international opportunities

25. Current/ Planned Work • New booster completed • Payload nearing completion • Sebastian River outreach activity April 3rd • Scheduled launch with full electronic payload April 4th • Complete verification of payload electronics done beforehand • Prepare for trip to Huntsville!

26. Conclusion • Panther II Heavy builds on previous high-powered model rocket experience to successfully compete in USLI competition • Panther II Heavy will advance NASA slosh dynamics research and provide benchmark data to NASA UCAT rocket modeling tool • Over 50 Florida Tech students and 3 faculty members participating • Project is on schedule and cost • Questions?