Critical Design Review (CDR)

CRITICAL DESIGN REVIEW (CDR)Charger Rocket WorksUniversity of Alabama in HuntsvilleNASA Student Launch 2013-14Kenneth LeBlanc (Project Lead)Brian Roy (Safety Officer)Chris Spalding (Design Lead)Chad O’Brien (Analysis Lead)Wesley Cobb (Payload Lead)

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Prometheus Flight Overview

Payloads Here

Payload DescriptionNanolaunch 1200 Record flight data for aerodynamic coefficients

Dielectrophoresis Use high voltage to move fluid away from container walls

LHDS Detect and transmit live data regarding landing hazards

Supersonic Coatings Test paint and temperature tape at supersonic speeds

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Technology Readiness Level

http://web.archive.org/web/20051206035043/http://as.nasa.gov/aboutus/trl-introduction.html

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Outreach• Adaptable for different ages and

lengths• Beginning outreach packet with

Elementary School• Building the program from the ground up

with school advisers• Supporting activity

• Water Rockets• Completed

• Science Olympiad• 102 Middle School• 54 High School

• Scheduled• Challenger Elementary

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On Pad Cost

Payload

Hardware

Recovery

Propulsion

$- $10,000.00 $20,000.00

$626.98

$506.94

$408.00

$820.91

$2,026.98

$15,506.94

$408.00

$15,820.91

Theoretical: $33.762Actual: $2,362

Cost

Syst

em

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ANALYSIS

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Analysis Responsibilities• Fin Flutter Analysis• RockSim/Open Rocket Trajectory Simulations• MATLAB 3DOF Simulations• Monte Carlo Simulations• FEA Analysis using MSC PATRAN and NASTRAN• CFD Analysis using CFD-ACE+

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Flight Trajectory• Max Altitude: 15800 ft• Max Velocity: 1600 ft/s, Mach: 1.45• Acceleration: 40 G

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Flight Trajectory

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Flight Trajectory

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Vehicle Aerodynamics – M4770

• Static Margin – 1.61• CP – 92 in• CG – 84.4in

• Thrust To Weight • Max Thrust – 1316 lbf T2W: 40• Average Thrust – 1073 lbf T2W: 33.5

• Exit Rail Velocity – 122 fps

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Final Motor Selection - CTI M4770-P

• ISP – 208.3s• Loaded Weight: 14.337 lb• Propellant Weight: 7.3 lb• Max Thrust: 1362 lbf

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Monte Carlo Analysis

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Proof of Randomization in Inputs

• Shows output consistency overmultiple sets of simulations.

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Drift Analysis

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Variation in Flight Time

• Time variance directlyaffects the radial landingdistance.

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CFD - Critical Mach Number

*Steady state values Indicated by color maps

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CFD – Aerothermal Heating

*Steady state values Indicated by color maps

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CFD - Drag vs Mach Plot

• Uncertainty with Mach < 0.5• Inadequate convergence in low Mach Regime

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Plan B Motor: CTI-L890

Cross Wind 5mph 10mph 15mph 20mph 25mph

Drift 900ft 1950ft 3050ft 4250ft 4700 ftMain Deployment

Altitude 750ft 750ft 750ft 750ft 500ft

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Recovery System

• Single Separation Point• Main Parachute

• Hemispherical• 12 ft • Cd 1.2• Nylon

• Drogue Parachute• Conic• 2.5 ft• Cd 0.71 (experimentally determined)• Nylon

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Recovery System Deployment Process

• Stage 1• 2 seconds after apogee • nose cone separates• release the drogue

• Stage 2• 2.1

• Drogue attached via tethers.• 2.2

• A black powder charge separates the tethers

• Stage 3• Main parachute pulled from

deployment bag

Eye bolt

L.H.D.S

Tethers

Black Powder Charge

Drogue

Main Parachute InDeployment bag

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Stage 1: Drogue DeploymentStage 2.1

Stage 2.2

Stage 3

Deployment Process

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Energy and Velocity at Key Points

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Sewing Technique• Seam Type: French Fell • Vent Hole supported with double stitched bias tapes• The bottom edge hemmed

• Prevent fraying• Increase durability

Stich Seam Cross Section

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Subscale Drogue• Flight Test

• Built by team• First attempt

• Subscale Data• Perfect flight Altimeter• Cd of 0.71• 27.5” Diameter

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Construction Materials

•Swivel ultimate load:1045 lbs•The nylon line anchor points ultimate load: 120 lbs per strap•The eyebolt ultimate load: 500 lbs

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DESIGN

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Hardware Team responsibilities:

• Vehicle design

• Testing and verification of

materials and components

• Vehicle construction

• Interfaces

Design Details:

• 34lbs

• 40Gs acceleration

• Geometric similarity to NASA

Nanolaunch protoype

• Nanolaunch team requested

maximum use of SLS printed

titanium

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Interfaces (1)# Component Interface Method Load Locations1 Pitot probe Threaded to nosecone shaft Tension from pitot shaft, compression

from nose cone, aerodynamic forces

2 Nosecone Slip fit with Shear Pins Compression from pitot probe and slip ring, aerodynamic forces

3 Nosecone Payload

Threaded to nosecone shaft Acceleration forces, passed through nose cone shaft

4 Nosecone shaft Threaded to pitot probe Tension loads between the nose cone bulkhead and pitot probe, compression/ tension from payload acceleration forces

5 Nosecone Bulk head

Slipped over payload shaft Tension from payload shaft/ ring nut

Nose cone slip ring

Slipped into body tube with shear pins, retained to nose cone with nose cone shaft

Compression from nose cone and body tube, aerodynamic forces

6 Nosecone shaft nut

Threaded to nosecone shaft Tension from payload shaft

7 Recovery package Shock cord / knot / ring nut Tension from ring nuts, aerodynamic forces

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Interfaces (2)8 Payload Slipped onto payload shaft/

constrained between nutsAcceleration forces, passed through payload shaft

9 Lower slip ring Held in compression between body tube sections with payload shaft

Compression from upper and lower body tubes, aerodynamic forces

10 Payload shaft Threaded to motor case / lower bulk head / ring nut

Tension between bulkheads and ring nut, compressive and tensile forces from payloads under acceleration

11 Centering ring Slipped onto payload shaft/ constrained between nuts

Radial location of motor case; negligible forces

12 Motor case Threaded to payload shaft Outside manufacture; loaded in designed manner

13 Fins / Fin brackets Bolted to lower body tube/ T nuts inside body tube

Aerodynamic and acceleration forces, resulting tension from body tube

14 Thrust ring Held in compression between motor case and body tube

Compression from motor case

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Thrust Ring

• Printed titanium

• Analyzed with FEA

• Significantly stronger than

required

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Fin Assemblies

• Modified significantly since PDR due to

updated geometry from Nanolaunch

team (bolted instead of epoxied)

• Easier to inspect and verify

• Fin replacement in the field now

possible

• Moderate weight penalty compared to

original design.

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Body Tube

• Carbon composite

• FEA, destructive testing and

hand calculations done to assess

strength

• Large margin of safety and low

weight

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Payload Shaft

• 7075-T6 Aluminum threaded shaft

• Preloaded in tension

• FEA and hand calculations show significantly over strength requirements

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Payload Shaft Load Paths

• Carries thrust loads into payloads and recovery forces into lower rocket, as

well as providing assembly method for payloads, body tubes and recovery

harness

• Red Arrow indicates motor loads from thrust ring through body tube

• Green arrow indicates motor loads passed through payloads

• Blue arrow indicates recovery forces passed through payload shaft

• Orange arrow indicates motor case retention force

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Coupler Rings

• Machined aluminum

• Aft coupler retained by

payload shaft preload

• Fore coupler retained by

nose cone shaft and shear

pins

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Nose Cone Assembly

• All components retained by shaft similar to payload shaft

• Carbon fiber nose cone shroud and bulkhead

• Contains pitot pressure and accelerometer/ gyro data package

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Pitot Probe

• Allows measurement of static

pressure along with supersonic

AND subsonic total pressure

• Unique and original design which

could only be made with 3D

printing techniques

• Helps fulfill our Nanolaunch

request to explore selective laser

sintering in original ways.

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Structure Testing• Carbon fiber dog bones

• Loaded in tension • Verify tensile strength of materials

• Tubes• Loaded in compression• Verify compressive strength of

representative structures of body tube

• 45/45 Sleeve• 0/90 Wrapped

• Parachute Material• Loaded in tension • Verify parachute material and

seam strength

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Tension Results

Test Sample Failure Load (lbf) Max Extension (in)1 1951.4 0.0862 1785.3 0.0743 1781.8 0.0684 1732.8 0.0645 1820.3 0.084

Average 1814.3 0.075Standard Deviation 82.7 0.010

Dog Bones

0.00E+001.00E-022.00E-023.00E-024.00E-025.00E-026.00E-027.00E-028.00E-029.00E-02

0 500 1000 1500 2000

Exte

nsio

n (in

)

Load (lbf)

Average Load vs. Extension

Fractures

FracturesDog bones

• Verified Strength Requirements• Fractures showed uniformity in

the angle of the fibers• Calculated Young Modulus to

be 309 ksi

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Compression ResultsFractures

Test Sample Failure Load (lbf) Max Compression (in)Sleeve 6226.1 0.139

Wrapped 8093.5 0.070

Tubes

0100020003000400050006000700080009000

40 50 60 70 80 90 100

Load

(lbf

)

Time (s)

Tube Compressive Strength

Tubes• Wrapped tube holds the most

force• Fractures showed uniformity in

the angle of the fibers• Failure Load: 8094.5 (lbf)

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Parachute ResultsSeam Test

• Seam failed before material• Breaking of seam occurred at

35 lbf• Narrow sample failed at seam

due to edge effects

0

5

10

15

20

25

30

35

40

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0 20 40 60 80 100 120 140

Load

(lbf

)

Time (s)

Parachute Strength

Test Sample Failure load (lbf) Max Extension (in)1 35.71812 1.792 39.05464 1.87

Parachute

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Structure Testing Conclusions

Verified Requirements • Strength• Thickness• Fiber Angle • Fabrication

Future Testing• Recovery system• Electronic payload• Verification of flight hardware• Flight testing completed rocket

Test Sample Failure Load (lbf) Max Extension (in)1 1951.4 0.0862 1785.3 0.0743 1781.8 0.0684 1732.8 0.0645 1820.3 0.084

Average 1814.3 0.075Standard Deviation 82.7 0.010

Dog Bones

Test Sample Failure Load (lbf) Max Compression (in)Sleeve 6226.1 0.139

Wrapped 8093.5 0.070

Tubes

Test Sample Failure load (lbf) Max Extension (in)1 35.71812 1.792 39.05464 1.87

Parachute

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Vehicle Requirements

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PROCEDURES

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Testing ProceduresTest

Requirement Identified

Develop Operating

Procedures

Review of Procedures

by PRC Staff

Procedure Approval by

PRC Director

Identify Red Team

Members for Test

Review of Operating

Procedure with Red Team

Approval of Red Team Members

Testing

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Subscale Testing and ResultsSub-Scale Flight Test Matrix

Type of Test Test Goals Results

Sub-Scale Flights Verify the vehicle stability margin and flight characteristics. Successful (2/8/14)

Flight ElectronicsEnsure that payload records proper data and that launch detect functions properly.

Partial Success (2/22/14)

Recovery System Hardware

Test hardware that will allow for a single separation dual deploy setup in full-scale vehicle.

Partial Success (2/22/14)

Parachute DesignVerify construction techniques are adequate and determine effective drag coefficient.

Success (2/22/14)

High Acceleration Flight (40+ G’s)

Ensure that avionics will survive launch forces of full-scale. Not Yet Tested

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Recovery Hardware Testing

• Problems with deployment bag.• Successful proof of concept flight for parachute design.• Successful test of separation charges.

Deployment Bag Failure Point

CRW Built Parachute

Separation Charges

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Subscale Flight Data

• Apogee: 1,573 feet AGL.• Max Velocity: 279 ft/s.• Time of Flight: 63.9 seconds.• Motor: CTI I-205.• Recorded Using a PerfectFlite SL100

• Apogee: 4,156 feet AGL.• Max Velocity: 597 ft/s.• Time of Flight: 128.6 seconds.• Motor: Aerotech I-600.• Recorded Using a PerfectFlite SL100

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PAYLOADS

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Nanolaunch Experiment Overview• Calculating Aerodynamic Coefficients

• Pitching moment Coefficient• Drag Coefficient• Measure base pressure

• Two separate sensor packages• Accelerometers• Gyroscopes• Pressure sensors

• Similar not identical• Nosecone

• Pitot probe• 60 PSI• 100 PSI

• Near CG• Base pressure sensors

• 30 PSI• Designed for future use

CG Configuration

ADXL345

ADXL377

L3GD20

30 PSIPressure Sensors

ADC

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Nanolaunch Testing• Sensor Output

• Ground tests - Breadboard• Calculated Pressure Sensor Gain• Tested Code Functionality • Sampling at 48 Hz per sensor

• Subscale Flight – Data Extracted• Full Scale flight to Come

• Will Include Pressure Sensors

• EMI Testing• Test for EMI interference with

sensors• Ground tests

Subscale Payload Bay

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Nanolaunch Payload Test Matrix• Tested Methodically• Successful Payload Data Extraction During Subscale

Launch

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Nanolaunch Success Criteria• Objectives: Meet Team/NASA SLI Requirements and

Verify Those Were Met

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Outcomes and Nanolaunch Path Forward

• Outcomes:• Successfully Extracting Data• Preliminary Data/Results

• Rocket Angular Velocity: Will be Calculated Based on Sign Change in Accelerometer Data

• Path Forward• Record More Launch Data for Data Comparison• Create Data Buffer( To keep 30 seconds of data prior to launch

detect)• Calibration of Sensors• Raise the ADXL345 Accelerometers to 16G setting.• Incorporate Amplified Pressure Sensors and ADC Into Circuit

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Dielectrophoresis (DEP)• Fluid manipulation

• Electric field• Peanut oil

• Voltage• Voltage squared drives strength of electric field

• Fluid• Dielectric constant determines fluid interaction

• Electrode geometry• Gradient of electric field depends on geometry

Uniform Electric Field

Positive Region Negative Region

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Experimental Changes

• Electrode configuration: from parallel electrodes, to annular electrodes

• Voltage increase from 7kV to ~12kV

2012-2013 Configuration

2013-2014 Configuration

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DEP Testing• EMI Testing

• Test next to flight ready recovery system• Minus gunpowder

• Test next to Nanolaunch• Test and Prove design

• Test revised circuit• Structure tests

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DEP Success Criteria Requirement Success Criteria Verification

Microgravity environment Reach apogee of flight to experience microgravity

environment

Retrieve accelerometer data determine duration of

microgravity environment Manipulate fluid with electric

field Noticeable collection of fluid

around central electrode Retrieve camera and accelerometer data

Perform experiment without interfering with other payloads

Reliable data collection from all payloads adjacent to DEP

Rigorous preflight testing .Post flight analysis of data.

Recoverable and reusable Fluid containers intact. No electrical shorts. Functional

electronics

Recover the payload. Return to flight ready state with no

repairs needed.

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Supersonic Paints and CoatingsUrethane Epoxy

Epoxy

•Urethane • Excellent retention• Abrasion resistant • Smooth Coating

•Epoxy Primer• Low film build• Excellent adhesion• Rough Coating

•Thermal tape• 3-5 second reaction time• Changes color at specific

temperatures• Excellent Adhesion

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SPC Testing• Oven Testing for Temperature tape

• Calibration of tape• Temperature sensitivity • Reaction time

• Flight Test• Subscale Test Flight• Full scale test launch

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Success Criteria of Paints and Coatings

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Landing Hazard Detection• Beaglebone

• Camera cape• C++ libraries• Established knowledge base

• 3 Methods of Analysis• Color detection• Edge detection• Shadow analysis

• Grid analysis• Faster processing

• Orientation• Use accelerometer to filter images of the ground

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Radio• RF Module: XBee-PRO XSC S3B

• 900 MHz transmit frequency• 20 Kbps data rate• 9 mile LoS range• 250 mW transmit power• 3.3 VDC supply voltage• 215 mA current draw• 1.5+ hr battery life at max sensor sample rate• Laptop ground station

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GPS Tracking• GPS Module: Antenova M10382-Al

• GPS lock from satellites• Transmits data through XBee RF module• 8 ft accuracy with 50% CEP• 3.3 VDC supply voltage• 22 to 52 mA current draw

• Redundant GPS Unit: “Tagg Pet Tracker”• Supported by Verizon cell network• Smartphone based ground station• 25 ft accuracy with 95% confidence• Self-contained power source• 3.5+ days battery life

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LHDS Testing• Test Flights

• Full scale only• Alter method for different launch field

• Bench Test• White wall simulates salt flats• Colored paper as “hazards”• Google Map images

Hera Launch FieldManchester, TN

Bonneville Salt Flats, UT

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LHDS Success Criteria

Requirement Success Criteria Verification

Transmit LHDS data in real time to a ground station.

Data is sent from RF module aboard rocket to ground station

without loss or corruption.

Transmitted data is received by ground station. Data is verified using either Checksums or post-

flight data comparison.

The payload shall be recoverable and reusable.

Recover the RF module and reuse it.

The RF module is recovered and can be launched again on the

same day.

Transmit live GPS DataRF module transmits live GPS

data from the GPS module to the ground station.

GPS location of the rocket is received by the ground station.

The electronic tracking device shall be fully functional during

the official flight at the competition launch site.

GPS data is sent through RF module aboard the rocket to the

ground station during the competition launch.

GPS location data from the rocket is received by the ground

station during the official flight at the competition.

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THANK YOU

QUESTIONS?