GREEN ROCKETRY

USLI 2011-12 Critical Design ReviewFebruary 8, 2012 – 3:00PM

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

Team SummaryTeam Summary

School Tuskegee University

Location Tuskegee, Alabama

Team Officials Dr. M. Javed Khan, Department Head and Professor, ASEng.

Dr. Vascar G. Harris, Professor, ASEng.

Safety Officer Troy Cole

Team Members

Name Team Role Major Classification

Troy Team Lead Aerospace Engineering Senior

Devin Assistant Lead Aerospace Engineering Freshman

Eldon Structures Group Lead Materials Science & Eng. Doctoral Student

Craig Payload Group Lead Aerospace Engineering Junior

Keith Aerodynamics Lead Aerospace Engineering Freshman

Tungie Recovery Group Lead Aerospace Engineering Freshman

Tiffany Propulsion Group Lead Aerospace Engineering Freshman

Chris Short NAR/TRA Mentor SEARS-572 - Prefect, SEARS 572 TRA/NAR

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

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

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

Separation point Main parachute #1 – 1000 feet AGL

Separation point Drogue parachute – Apogee

Separation point Main parachute #2 – 1000 feet AGL

Blue = airframe and bulkhead skin

Green = parachute Pink = Propellant in casing

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

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™

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

Envirez 1807 Resin

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

Mechanical Properties

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

KE for Apogee to Main Deployment

Rocket Component Mass and Kinetic Energy - Apogee to MPD*

Section Mass (lb)Velocity(ft/sec)

Kinetic Energy - ft*lbf

1 4.3 83.18 462

2 10.88 83.18 1169

3 5.41 83.18 581

4 12.07 83.18 1297

Total 32.66   3509

Rocket Component Mass and Kinetic Energy – Main to Landing*

Section Mass (lb)Velocity(ft/sec)

Kinetic Energy - ft*lbf

1 4.3 12.28 10.07

2 10.88 12.28 25.49

3 5.41 12.28 12.67

4 12.07 12.28 28.28

Total 32.66   76.51

Airframe sections

Motor section

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)

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

Flex Sensor™

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)

Altimeter Section cross section (4)

Propulsion (choices)

Motor

Liftoff Mass

(Kg)

Guide Velocity

(m/s)

Burnout Mass (Kg)

Burnout Time (s)

Burnout Altitude

(m)

MaxAcceleration

(G)

Max Velocity (m/s)

Apogee Time

(s)

Max Altitude

(m)

Optimal Delay (s)

AeroTech K1499 17.163 23.108 16.559 0.871 32.479 9.294 69.350 7.621 259.800 6.750

AeroTech K780 18.356 15.047 17.088 3.020 166.450 4.392 101.430 12.383 612.390 9.363

AeroTech K1000 18.024 17.584 16.790 2.490 161.320 5.555 115.540 12.990 730.040 10.500

AMW L1111 18.939 15.705 17.297 3.130 257.670 6.700 154.810 16.280 1181.000 13.150

AeroTech L1150 19.096 18.575 17.194 3.118 265.090 6.158 154.180 16.230 1181.200 13.113

Loki L930 18.960 15.516 17.055 3.990 329.240 5.146 148.770 16.740 1189.400 12.750

GR L1150 18.924 17.370 17.174 3.100 281.670 8.692 158.560 16.500 1244.500 13.400

AeroTech L850 19.164 16.946 17.069 4.680 455.920 5.436 149.650 17.030 1260.000 12.350

AeroTech L1520 19.073 21.305 17.219 2.590 253.400 8.283 175.000 16.890 1363.500 14.300

Loki L1482 18.960 19.502 17.121 2.590 239.280 8.487 182.280 17.340 1425.100 14.750

AeroTech L1390 19.301 19.789 17.328 2.910 287.950 7.906 177.670 17.410 1434.000 14.500

AeroTech L1170 20.412 18.737 17.612 3.660 374.540 6.402 175.750 17.910 1475.100 14.250

GR L1065 20.785 19.221 18.092 3.940 468.320 7.887 177.550 18.290 1583.100 14.350

AeroTech L1420 19.984 20.086 17.424 3.230 356.470 7.753 202.990 19.030 1745.300 15.800

AeroTech L1120 20.080 19.638 17.302 4.993 653.720 7.048 194.660 19.855 1860.600 14.863

Propulsion – Loki L930

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

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 – altimetersAssemble prior to launch test to avoid any

static discharge or miscalculations on powder volume

Risk Assessment

Risk Assessment - Pre-Launch/Launch

Risk Result Safety Risk Likelihood Prevention/Mitigation

Separation Charge/Igniter Arming

Detonation of separation charges at arming

Injury to ground crew and vehicle

High LowEnsure static charges do not build

up/proper use of arming switches

Premature ignition of motor

Injury to ground crew and vehicle

High LowEnsure igniter is properly grounded

before insertion and insert igniter just before launch

Unstable platformInjury to ground crew and

vehicleMedium Low

Ensure ground equipment is stable before loading vehicle on pad.

FFFFg Black Powder Charge Construction

Accidental detonation of separation charge

Injury to ground crew and vehicle

High MediumEnsure proper grounding of e-match

before encasing in FFFFg

Underpowered separation charges

Incomplete deployment of parachute - vehicle

damageMedium Low

Measure FFFFg carefully and ensure no spillage

Overpowered separation charge

Excessive pressure on vehicle components - vehicle

damageMedium Low

Measure FFFFg carefully and ensure no spillage

Risk Assessment – cont.

Risk Assessment - Recovery

Risk Result Safety Risk Likelihood Prevention/Mitigation

Separation Charge / FFFFG Assessment

Failure to ignite/ detonate Ballistic return - loss of vehicle High MediumUtilize redundant altimeters with charge

detonation capability

Premature detonation - in flightEarly separation of sections -

catastrophic loading on vehicle

Medium MediumEnsure proper wiring and settings on

altimeters

Ground detonation prior to launch

Injury to ground crew and vehicle High LowAltimeters will not be armed until vehicle is

on launch pad just prior to launch

Parachute - Drogue

Failure to fully deploy - entangled

Lack of stabilization and increased descent velocity

Medium HighEnsure proper packing, use of parachute bag,

use of swivel on parachute/shock cord interface

Tearing or burningLack of stabilization and increased

descent velocityMedium Medium

Use of parachute bag, ensure deployment at apogee

Riser line breakageLack of stabilization - increased

descent velocityMedium Low

Use of parachute bag, ensure deployment at apogee

Risk Assessment – cont.

Risk Assessment - Recovery

Parachute - Main

Failure to fully deploy - entangled

Increased descent velocity - impact with ground causes significant

damage to vehicleMedium High

Ensure proper packing, use of parachute bag, use of swivel on parachute/shock cord

interface

Tearing or burningIncreased descent velocity - impact with ground - significant damage to

vehicleMedium Medium

Use of parachute bag, ensure deployment at apogee for minimum velocity deployment

Riser line breakageIncreased descent velocity - impact

with ground causes significant damage to vehicle

Medium LowUse of parachute bag, ensure deployment at apogee for minimum velocity deployment

Electronics

Altimeter failure Ballistic return - loss of vehicle High LowDual fault tolerant system with three

altimeters

Wiring Failure Ballistic return - loss of vehicle High LowDual fault tolerant system with three

altimeters

Battery failure Ballistic return - loss of vehicle High LowDual fault tolerant system with three

altimeters

Outreach

Teaming with ASEE to conduct two middle school sessionsBTW Middle School (~75 students)Phenix City Intermediate (~200 students)

Dates tentative on schools (before 1 March)

Questions?