Biodegradable Rocketry Project - Design Evolution and Performance Analysis

1. GREEN ROCKETRY USLI 2011-12 Critical Design Review February 8, 2012 – 3:00PM

2. Outline • Team Introduction and Goals • Changes made since PDR • Vehicle Description – Overall • Dimensions and performance • Materials • Kinetic Energy • Propulsion • Payload Design, Verification, and Test Plan • Vehicle Safety Verification and Testing • Outreach activities

3. Team Summary

4. Goals • To design, build and launch a rocket using bio-composite materials and verify modeling data • Prove that larger sounding rockets can be built from biodegradable and bio-renewable materials • Design Drivers – • Validate material properties in laboratory setting • Test materials in a real-world setting • Ensure safe launch and recovery of vehicle

5. Changes Made Since PDR • Vehicle Dimensions / Materials • Changes to kinetic energy – reduction in weight • Changes to resin system – change from polyester to epoxy resin (autoclave damaged) • Parachutes • Separation of vehicle at motor section / electronics section • Second parachute for motor section – deploy at 1000 feet (96 inch diameter) • Increase size of original parachute from 96 inch to 120 inch • Motor – Change from L1482 to L930 because of a reduction in weight

6. Vehicle Description • Length – 112.75 inches • Diameter – 5.20 inches outer, 5.0 inches inner • Mass • Launch: 36.2 lbf • Descent: 32.0 lbf (propellant = 4.2 lbf) • Static margin – 2.21 • CP – 77.3 inches from nose • CG – 65.9 inches from nose Pink = Propellant in casing Blue = airframe and bulkhead skin Green = parachute Separation point Main parachute #1 – 1000 feet AGL Separation point Main parachute #2 – 1000 feet AGL Separation point Drogue parachute – Apogee

7. Vehicle Performance • Max altitude: 5,281 ft AGL • Max Velocity: 574.43 ft/sec vertical • Max Acceleration: 10.13 g • Max drift @ landing (15-25mph winds): 173 feet • Thrust (Max/average): 255.5lbf / 209.1lbf • Burn time: 4.0 sec • Motor: Loki L930 Blue

8. Materials – Airframe (Overview) • Below nosecone • Fabric: Jute fiber and flax fiber woven cloth • Resin: SC-15 epoxy resin • Use of nano-clay and miscible rubber toughening agent to increase tensile strength and damage tolerance • Justification • Switch from Envirez 1807™ to SC-15™ because autoclave has been damaged (electronics) and will not be usable for 3-6 months • Switch allows components to be made in sections larger than 12 inches (currently largest possible in vacuum ovens) • Parts in the 12 inch range (fins, electronics boards, etc) will be still made of Envirez 1807™

9. Jute fabric • Mechanical Properties • Young's modulus 300 - 780MPa • Tensile strength 453 - 550MPa • Elongation 0.8 - 2% • Physical Properties • Density 1440 - 1460kg/m3 • Water absorption 2.0% if treated with KOH/Acetic acid before use

10. Envirez 1807 Resin

11. SC-15 Epoxy Resin • Two-phase epoxy cycloaliphatic amine. • Most widely data based VARTM/SCRIMP matrix resin which includes United Defense, Army, and several Phase II SBIR's for ballistic panels. • SC-15 Data: • Toughened Two-Phase • Mix ratio: 100:30 • Viscosity: 350 cps at ambient 77°F temp • 9.15 lbf per gallon • Cure cycle: 12 hours at 77°F • Post cure: 2 hours at 200°F • Tg (dry: 228°F; wet: 178°F) • Flex: 19.1 psi; Modulus 390 ksi (un-reinforced neat resin) • Water absorption: 1.3% • Will be toughened with Cloisite 6A nanoclay and miscible rubber toughening agent to ensure impact toughness

12. Mechanical Properties

13. Nose cone • Nosecone • Performance Rocketry 5:1 Ogive • E-glass/epoxy • Used previously in other flight vehicles – proven capabilities • One being used has been used previously in 5 other flights – bulkhead / retaining ring is well bonded

14. KE for Apogee to Main Deployment

15. Airframe sections • Motor section

16. Science Payload Section (2) • Arduino Uno – collect and process data from Flex Sensors™ • XBee 900MHz transmitter – transmit data to ground station for redundancy • 4.5 inch Spectra Symbol Flex Sensor™ (x 6) • Breadboard – link components • Power • 7-12V for Uno (will use 11.1V Li-PO) • 3.3V for XBee (Separate battery system)

17. Arduino Uno Specs • ATmega328 microcontroller • Input voltage - 7-12V • 14 Digital I/O Pins (6 PWM outputs) • 6 Analog Inputs • 32k Flash Memory • 16Mhz Clock Speed • Open source code/programming

18. Flex Sensor™

19. Altimeter section • One Strato-logger SL-100 altimeters • One Perfectflite MAWD altimeter • One ARTS2 altimeter • One TX-900G GPS/900MHz transmitter • One AT-2B RF tracking device (222.390MHz) • One BoosterCam video camera (Side of science package section)

20. Altimeter Section cross section (4)

21. Propulsion (choices)

22. Propulsion – Loki L930

23. Payload Verification/Test • Component integration • Power supply testing for duration • Code written and tested for microcontroller (Arduino Uno) – open source • Save onboard data plus transmit to ground station • Collect and compare data sets to NASTRAN results

24. Payload Safety • Isolate power supply (Li-PO batteries) • Risk of fire if damaged or overcharged • Static electricity discharge • Isolate and ground all sources • Ejection charges – altimeters • Assemble prior to launch test to avoid any static discharge or miscalculations on powder volume

25. Risk Assessment

26. Risk Assessment – cont.

27. Risk Assessment – cont.

28. Outreach • Teaming with ASEE to conduct two middle school sessions • BTW Middle School (~75 students) • Phenix City Intermediate (~200 students) • Dates tentative on schools (before 1 March)

29. Questions?