CRITICAL DESIGN
REVIEW (CDR)
Charger Rocket Works
University of Alabama in Huntsville
NASA Student Launch 2013-14
Kenneth LeBlanc (Project Lead)
Brian Roy
(Safety Officer)
Chris Spalding (Design Lead)
Chad O’Brien
(Analysis Lead)
Wesley Cobb
(Payload Lead)
2
Prometheus Flight Overview
Payload
Description
Nanolaunch 1200
Record flight data for aerodynamic coefficients
Dielectrophoresis
LHDS
Supersonic Coatings
Use high voltage to move fluid away from container walls
Payloads Here
Detect and transmit live data regarding landing hazards
Test paint and temperature tape at supersonic speeds
3
Technology Readiness Level
http://web.archive.org/web/20051206035043/http://as.nasa.gov/aboutus/trl-introduction.html
4
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
5
On Pad Cost
$15,820.91
System
Propulsion
$820.91
$408.00
$408.00
Recovery
$15,506.94
Hardware
Theoretical: $33.762
Actual: $2,362
$506.94
$2,026.98
$626.98
Payload
$-
$10,000.00
Cost
$20,000.00
6
ANALYSIS
7
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+
8
Flight Trajectory
• Max Altitude: 15800 ft
• Max Velocity: 1600 ft/s, Mach: 1.45
• Acceleration: 40 G
9
Flight Trajectory
10
Flight Trajectory
11
Vehicle Aerodynamics – M4770
• Static Margin – 1.61
• CP – 92 in
• CG – 84.4in
• Thrust To Weight
• Max Thrust
– 1316 lbf
• Average Thrust – 1073 lbf
T2W: 40
T2W: 33.5
• Exit Rail Velocity – 122 fps
12
Final Motor Selection - CTI M4770-P
•
•
•
•
ISP – 208.3s
Loaded Weight: 14.337 lb
Propellant Weight: 7.3 lb
Max Thrust: 1362 lbf
13
Monte Carlo Analysis
14
Proof of Randomization in Inputs
• Shows output consistency over
multiple sets of simulations.
15
Drift Analysis
16
Variation in Flight Time
• Time variance directly
affects the radial landing
distance.
17
CFD - Critical Mach Number
*Steady state values Indicated by color maps
18
CFD – Aerothermal Heating
*Steady state values Indicated by color maps
19
CFD - Drag vs Mach Plot
• Uncertainty with Mach < 0.5
• Inadequate convergence in low Mach Regime
20
Plan B Motor: CTI-L890
Cross Wind
5mph
10mph
15mph
20mph
25mph
Drift
900ft
1950ft
3050ft
4250ft
4700 ft
Main Deployment
Altitude
750ft
750ft
750ft
750ft
500ft
21
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
22
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
In
Deployment bag
23
Deployment Process
Stage 2.1
Stage 1: Drogue Deployment
Stage 3
Stage 2.2
24
Energy and Velocity at Key Points
25
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
26
Subscale Drogue
• Flight Test
• Built by team
• First attempt
• Subscale Data
• Perfect flight Altimeter
• Cd of 0.71
• 27.5” Diameter
27
Construction Materials
•Swivel ultimate load:1045 lbs
•The nylon line anchor points ultimate load: 120 lbs per strap
•The eyebolt ultimate load: 500 lbs
28
DESIGN
29
Hardware Team responsibilities:
Design Details:
• Vehicle design
• 34lbs
• Testing and verification of
• 40Gs acceleration
materials and components
• Vehicle construction
• Interfaces
• Geometric similarity to NASA
Nanolaunch protoype
• Nanolaunch team requested
maximum use of SLS printed
titanium
30
Interfaces (1)
#
1
Component
Pitot probe
Interface Method
Threaded to nosecone shaft
Load Locations
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
31
Interfaces (2)
8
Payload
Slipped onto payload shaft/
constrained between nuts
Acceleration forces, passed through
payload shaft
9
Lower slip ring
Held in compression between Compression from upper and lower body
body tube sections with
tubes, aerodynamic forces
payload shaft
10 Payload shaft
Threaded to motor case / lower Tension between bulkheads and ring nut,
bulk head / 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
14 Thrust ring
Aerodynamic and acceleration forces,
resulting tension from body tube
Held in compression between Compression from motor case
motor case and body tube
32
Thrust Ring
• Printed titanium
• Analyzed with FEA
• Significantly stronger than
required
33
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.
34
Body Tube
• Carbon composite
• FEA, destructive testing and
hand calculations done to assess
strength
• Large margin of safety and low
weight
35
Payload Shaft
• 7075-T6 Aluminum threaded shaft
• Preloaded in tension
• FEA and hand calculations show significantly over strength requirements
36
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
37
Coupler Rings
• Machined aluminum
• Aft coupler retained by
payload shaft preload
• Fore coupler retained by
nose cone shaft and shear
pins
38
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
39
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.
40
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
41
Tension Results
Fracture
s
Dog bones
• Verified Strength Requirements
• Fractures showed uniformity in
the angle of the fibers
• Calculated Young Modulus to
be 309 ksi
Fracture
s
Extension (in)
Average Load vs. Extension
9.00E-02
8.00E-02
7.00E-02
6.00E-02
5.00E-02
4.00E-02
3.00E-02
2.00E-02
1.00E-02
0.00E+00
0
500
1000
Load (lbf)
1500
2000
Dog Bones
Test Sample
Failure Load (lbf)
1
1951.4
2
1785.3
3
1781.8
4
1732.8
5
1820.3
Average
1814.3
Standard Deviation
82.7
Max Extension (in)
0.086
0.074
0.068
0.064
0.084
0.075
0.010
42
Compression Results
Tubes
Fracture
s
• Wrapped tube holds the most
force
• Fractures showed uniformity in
the angle of the fibers
• Failure Load: 8094.5 (lbf)
Load (lbf)
Tube Compressive Strength
9000
8000
7000
6000
5000
4000
3000
2000
1000
0
Test Sample
Sleeve
Wrapped
40
50
60
70
Time (s)
80
90
100
Tubes
Failure Load (lbf) Max Compression (in)
6226.1
0.139
8093.5
0.070
43
Parachute Results
Seam Test
• Seam failed before material
• Breaking of seam occurred at
35 lbf
• Narrow sample failed at seam
due to edge effects
Parachute Strength
45
40
35
Load (lbf)
30
Test Sample
1
2
25
20
15
10
5
0
0
20
40
60
80
Time (s)
100
120
140
Parachute
Failure load (lbf)
35.71812
39.05464
Max Extension (in)
1.79
1.87
44
Structure Testing Conclusions
Verified Requirements
• Strength
• Thickness
• Fiber Angle
• Fabrication
Future Testing
• Recovery system
Dog Bones
Test Sample
Failure Load (lbf)
1
1951.4
2
1785.3
3
1781.8
4
1732.8
5
1820.3
Average
1814.3
Standard Deviation
82.7
Test Sample
Sleeve
Wrapped
• Electronic payload
• Verification of flight hardware
• Flight testing completed rocket
Test Sample
1
2
Max Extension (in)
0.086
0.074
0.068
0.064
0.084
0.075
0.010
Tubes
Failure Load (lbf) Max Compression (in)
6226.1
0.139
8093.5
0.070
Parachute
Failure load (lbf)
35.71812
39.05464
Max Extension (in)
1.79
1.87
45
Vehicle Requirements
46
PROCEDURES
47
Testing Procedures
Review of
Procedures by
PRC Staff
Develop
Operating
Procedures
Test
Requirement
Identified
Procedure
Approval by
PRC Director
Identify Red
Team
Members for
Test
Review of
Operating
Procedure with
Red Team
Testing
Approval of
Red Team
Members
48
Subscale Testing and Results
Sub-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 Electronics
Ensure 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 Design
Verify construction techniques
are adequate and determine
effective drag coefficient.
High Acceleration
Flight (40+ G’s)
Ensure that avionics will survive
launch forces of full-scale.
Success (2/22/14)
Not Yet Tested
49
Recovery Hardware Testing
CRW Built
Parachute
Deployment Bag
Failure Point
Separation Charges
• Problems with deployment bag.
• Successful proof of concept flight for parachute design.
• Successful test of separation charges.
50
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
51
PAYLOADS
52
Nanolaunch Experiment Overview
L3GD20
• Calculating Aerodynamic Coefficients
• Pitching moment Coefficient
• Drag Coefficient
30 PSI
• Measure base pressure
• Two separate sensor packages
• Accelerometers
• Gyroscopes
• Pressure sensors
• Similar not identical
ADXL345
Pressure
Sensors
ADXL377
ADC
• Nosecone
• Pitot probe
• 60 PSI
• 100 PSI
• Near CG
• Base pressure sensors
• 30 PSI
• Designed for future use
CG Configuration
53
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
54
Nanolaunch Payload Test Matrix
• Tested Methodically
• Successful Payload Data Extraction During Subscale
Launch
55
Nanolaunch Success Criteria
• Objectives: Meet Team/NASA SLI Requirements and
Verify Those Were Met
56
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
57
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
58
Experimental Changes
• Electrode configuration: from parallel
electrodes, to annular electrodes
• Voltage increase from 7kV to ~12kV
2012-2013
Configuration
2013-2014
Configuration
59
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
60
DEP Success Criteria
Requirement
Microgravity environment
Manipulate fluid with electric
field
Perform experiment without
interfering with other payloads
Recoverable and reusable
Success Criteria
Reach apogee of flight to
experience microgravity
environment
Noticeable collection of fluid
around central electrode
Reliable data collection from all
payloads adjacent to DEP
Fluid containers intact. No
electrical shorts. Functional
electronics
Verification
Retrieve accelerometer data
determine duration of
microgravity environment
Retrieve camera and
accelerometer data
Rigorous preflight testing .Post
flight analysis of data.
Recover the payload. Return to
flight ready state with no
repairs needed.
61
Supersonic Paints and Coatings
• Urethane
• Excellent retention
• Abrasion resistant
• Smooth Coating
Urethane
Epoxy
• Epoxy Primer
• Low film build
• Excellent adhesion
• Rough Coating
• Thermal tape
• 3-5 second reaction time
• Changes color at specific
temperatures
• Excellent Adhesion
Epoxy
62
SPC Testing
• Oven Testing for Temperature tape
• Calibration of tape
• Temperature sensitivity
• Reaction time
• Flight Test
• Subscale Test Flight
• Full scale test launch
63
Success Criteria of Paints and Coatings
64
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
65
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
66
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
67
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 Field
Manchester, TN
Bonneville Salt Flats, UT
68
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 postflight 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 Data
RF 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
GPS location data from the
module aboard the rocket to the rocket is received by the ground
ground station during the
station during the official flight at
competition launch.
the competition.
69