Wq
Post-Launch
Assessment Review
2010-2011
For the NASA University Student Launch
Initiative Competition
University of Central Florida
Department of Mechanical,
Materials, and Aerospace
Engineering
4000 Central Florida Blvd.
Orlando, FL 32816
Project Overview
Team Name
Team Members
Motor
Payload
Rocket Height
Rocket Diameter
Rocket Mass
Official Altitude
“Knight Rider”
David Cousin, Stephen Hirst, Drew Dieckmann,
Mitra Mossaddad, Freya Ford, Md Arif
Cesaroni L-995
SMD Payload – Atmospheric Sensing Package
118” (9.83 ft)
4.5”
29.5 lbs
5,210 ft
Vehicle Overview
“Knight Rider” was flown on an L-995 Cesaroni solid rocket APCP motor to an
official altitude of 5,210 ft, only 70 feet below the targeted mile height. It stood 118”
(9.83 ft) tall and weighed 29.5 lbs with a diameter of 4.5”. The payload consisted of the
SMD sponsored atmospheric sensing payload package. Looking at figure 1 below we
see that the rocket was made out of two different types of composite materials. Carbon
fiber was used for the motor mount section and the nose cone due to the fact that it has
a higher structural strength than fiberglass which was used for the avionics bay and the
payload due to the fact that carbon fiber was unable to transmit GPS signals. The
recovery system consisted of two 60” main parachutes and two 24” drogue parachutes
with the rocket separating completely into two parts, with one part being the motor
mount and the other avionics and payload and nose cone, at apogee
Figure 1 - Launch Configuration
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Vehicle Data Analysis and Results
Four PerfectFlite miniAlt altimeters were flown on the rocket. Two altimeters (a
primary and secondary) were positioned in the motor section while the other two were
placed in the payload section. From the competition flight, the altimeters logged
altimeter data and were taken for further analysis.
The graphs shown below are taken directly from the altimeters through
PerfectFlite’s DT2x Data Transfer Kit. The data was obtained for all altimeters while the
data for the primary altimeters are shown below. The graphs show the recorded flight
profile for the rocket’s two separated sections. Simple calculations of the data resulted
in the descent rates and drift velocities of our competition flight. Drift distance was
calculated as a function of the wind speed multiplied by the time of descent. It may be
observed from the graphs that the altitude in which the main parachute descent rates
were calculated from show a height of 590 ft and 570 ft for the motor and payload
section, respectively. The altimeters were set to deploy the main at 700 ft, which was a
successful deployment, however using 700 ft as the beginning of the main drift would be
erroneous due to the small time it takes for the parachute to fully deploy and slow down
the rocket to a constant rate. Therefore, the data was cropped for the constant section
only to accurately show the rates of descent. Additionally, the official altimeter reading
for our launch was the secondary altimeter in the payload section. The data for this
altimeter is not shown below; the official reading was not taken from either of these
altimeters.
The motor section’s descent rates were 67.94 m/s on the drogue and 21.11 m/s
on the main parachute. The payload section’s descent rates resulted in 55.83 m/s on
the drogue and 19.03 m/s on the main parachute. All of the calculated descent rates
were within the mission requirements. Wind speed was estimated at roughly 3 mph (4.4
ft/s) since there were almost no winds during the early morning hours, which resulted in
approximately 418 ft and 501.6 ft.
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tdrogue=83 s
tmain=31 s
hdrogue=5224ft
hmain=590 ft
Figure 2 - Motor Section Altimeter Data (Primary).
Table 1 - Descent Velocity and Drift Distance for the Motor Section.
MOTOR SECTION ALTIMETER
Parachute
Drogue
Main
Time (s)
95
Time (s)
68
27
Distance (ft)
4620
570
MOTOR SECTION DRIFT DISTANCE
Wind Velocity (ft/s)
Launch Day
4.4
Max
20
4
Average Velocity
(ft/s)
67.94
21.11
Drift Distance (ft)
418
1900
tdrogue=68 s
tmain=27 s
hdrogue=5190ft
hmain=570 ft
Figure 3 - Payload Section Altimeter Data (Primary).
Table 2 - Descent Velocity and Drift Distance for the Payload Section.
PAYLOAD SECTION ALTIMETER
Parachute
Drogue
Main
Time (s)
114
Time (s)
83
31
Distance (ft)
4634
590
PAYLOAD SECTION DRIFT DISTANCE
Wind Velocity (ft/s)
Launch Day
4.4
Max
20
5
Average Velocity
(ft/s)
55.83
19.03
Drift Distance (ft)
501.6
2280
Payload Overview
Onboard “Knight Rider” contained the requirements of the payload package
sponsored by the Science Mission Directorate (SMD). This included 7 atmospheric
sensors which monitor pre-flight, flight, and post-flight conditions. Measurements of
these 7 sensors include: pressure, temperature, humidity, acceleration, magnetism, UV
radiation, and solar irradiance. Additionally, 4 video cameras were flown from 4 different
perspectives to capture multiple angles of the launch.
Payload Data Analysis and Results
Pressure
Figure 4 below shows the pressure versus time graph the pressure sensor on the
arduino has recorded from the time it was turned on to the time it was turned off.
Converting to the standard SI units from hectopascal (hPa) the initial barometric
pressure recorded, before the rocket was launched, was measured to be 99,000 Pa.
The recorded pressure seems very reasonable compared to the standard atmospheric
pressure of 101,325 Pa, this might have been due to various facts, including but not
limited to the relative humidity, temperature, and density. Furthermore, analyzing the
graph we see that the pressure decreases with increasing altitude, from this conclusion,
observing the graph, we see the fact that minimum pressure of 82,000 Pa was reached
right around 18 seconds which was the time to apogee.
Figure 4 - Atmospheric Pressure Data
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Temperature
Figure 5 below shows the temperature versus time graph the temperature sensor
on board the arduino has recorded from the time it was turned on to the time it was
turned off. Observing the graph, we can see a temperature increase up until the time
the rocket was launched, this can be explained by the fact that the rocket was sitting out
at the pad for a while, this is given by the negative time values, and also for due to the
fact that the rocket was colored black which is a good heat absorber. Furthermore,
analyzing the graph we see that the temperature decreases with increasing altitude,
observing the graph, we can see this fact from a dip in the graph right after 0 seconds
with a minimum of 27º C right around the time to apogee of 18 seconds. A further
increase in the temperature after the rocket landed can be explained by the same
process mentioned above, while a decrease again starting right around 1500 seconds is
due to the fact that the payload was removed from direct sunlight and brought back to
the tent.
Figure 5 - Atmospheric Temperature Data
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Solar Irradiance
Figure 6 below shows the solar irradiance versus time graph the solar irradiance
sensor on board Knight Rider. Unfortunately, the solar irradiance sensor on board the
rocket did not function properly for the purposes of this competition but it has worked
well in the full-scale test launch that we had conducted before the competition.
Observing the graph one can see that the sensor did read data as the graph implies a
consistent reading of 0 W/m². The possibility that the battery might have detached from
the sensor turned off is not the reasonable due to the fact that the sensor was on when
the rocket was retrieved at the field. One definite possibility as to why this happened
could be due to the fact that the hole drilled was not large enough to reach the detector.
Figure 6 - Atmospheric Solar Irradiance Data
UV Radiation
The UV Radiation sensor on board Knight Rider unfortunately did not record any
data due to the same circumstances as with the solar irradiance sensor that light was
not able to penetrate into the UV Radiation sensor to record any measurements. The
UV sensor and the Solar Irradiance sensor both depend on sunlight to take
measurements and unfortunately if one of them does not function properly because of
limited light chances are very likely for the other to fail as well.
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Acceleration
Figure 7 below shows the acceleration versus time graph recorded by the
accelerometer sensor on board Knight Rider. The graph displays the acceleration in all
of the three axes x, y, and z relative to the spatial directions with y being in the vertical
direction. Observing the graph we see a minor spike in the acceleration in the x and z
directions due to the fact that gravity does not impede motion in these directions.
Furthermore, analyzing the graph we can estimate that the rocket hit the ground with
roughly 2 g’s, the impact was minimized with the aid of the large 60” main parachutes
that were used in the recovery system.
Figure 7 - Atmospheric Acceleration Data
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Humidity
Figure 8 below shows the relative humidity versus time graph recorded by the
humidity sensor on board Knight Rider. Observing the graph we see that the relative
humidity of the atmosphere was all over the place during the course of the period the
data was recorded. Analyzing the graph we see the fact that the data recorded was
legitimate due to the fact that during the course of the rockets ascent the humidity
decreased which matches the scientific principles that humidity decreases with
increasing altitude. Furthermore, we also see a further decrease in humidity even after
the rocket landed, which could be explained by changes in temperature and pressure
during the time differential and also from the relocation of the rocket after landing.
Figure 8 - Atmospheric Relative Humidity Data
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Magnetic Field
Figure 9 below shows the magnetic field of the earth in Gauss versus the time
plot recorded by the magnetic field sensor on board Knight Rider. The magnetic field
sensor on board the rocket recorded the magnetic field of the earth in all of the spatial
directions. Analyzing the recorded data we see that the magnetic field value in the x and
y axes directions were very minimal and decreased during the rockets ascent and
started increasing back again with descent and leveled off to approximately -0.35 gauss
a while after landing. While the magnetic field in the z direction was roughly about 0.65
gauss before the rocket was launched and decreased thereafter during ascent until the
rocket hit apogee where it reached a minimum value of roughly 0.42 gauss and then
started increasing again during the rockets descent and finally leveled off to a value of
roughly 0.25 gauss a while after landing. The data observed correspond to typical
recorded atmospheric magnetic field strengths of roughly between 0.38-0.58 gauss at
the Earth’s surface.
Figure 9 - Atmospheric Magnetic Field Data
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Figure 10 - Descent and Landing Pictures taken from camera on board Knight Rider
Lessons Learned
The final competition launch was very successful. The team did not encounter any
major issues. The rocket launched and landed safely. The UCF team has learned a lot
through out this entire project. The team members have learned about the basics of
rocketry, problem solving, following the guidelines while designing for the optimum
outcome, launch day adjustments and the launch process. Many lessons were learned
from the previous three test launches and were briefed as we encountered them.
From the final competition launch, we learned many lessons and had confirmations
of our expectations. One lesson that we learned was launching as early as possible in
the day would present ideal conditions for our rocket. Therefore, we launched on the
second rack of the day when there where almost no winds and temperature was
optimal. Additionally, we learned that the temperature within the rocket changes
drastically due to the outside temperatures. From the data that was received, the
temperature varied from 50° F to 95° F in about 40 minutes. This was due to the black
color of the rocket absorbing the direct heat of the sun. For different missions, this could
be a concern and may be minimized simply by changing the color of the rocket.
Summary of Overall Experience
Throughout the eight month course of the NASA-USLI project, the UCF team has
gained many valuable knowledge and experience, not only in the field of amateur
rocketry but as well as in many other fields including but not limited to fields such as
ITAR. Since our team was limited to only six people, all of which had very minimal
experience in rocketry, we had to weigh our options for project success. Since we had a
lack of experience, we needed to spend much time learning the basics of rocketry and
building so that the rocket would fly as required while being as safe as possible.
Therefore, the decision was made to put our primary emphasis on the performance of
our rocket, which involved dedicating much time building the rocket and doing test
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launches. Even though we had put a higher emphasis in building the rocket and
reaching the target altitude goal, this should not imply that we have spent little effort in
the design and documentation of our rocket. Before the UCF team attempted to build
the rocket an extensive analysis was conducted to follow all of the safety guidelines
mandated by Tripoli and NAR. Furthermore, several analyses were conducted including
the structural integrity, CFD analysis, as well as various analyses on the basis of
reaching the one mile target altitude using RockSim with multiple rocket motors and
making adjustments based on wind, angle of attack, and actual test launch data. What
we attempted to do coincided very well with the results that we attained at the
competition. Winning the altitude award was a tremendous achievement and major
testament to the amount of time and effort that the UCF team had made to make a safe
and reliable rocket without sacrificing rocket or payload performance.
Educational Engagement Summary
The UCF USLI team visited Oviedo High School on Friday, January 28, 2011
where we educated a total of eighty-one grade nine students through three different
Physics classes. The students at this high school are streamed and so two of these
were regular Physics classes while the third was an honors Physics class.
Students were given a small survey at the end of each visit to evaluate the
overall impact the activities had on them. Overall, the students found the presentation
to be interesting and agreed that they had learned a lot. Many expressed interest in
participating in the USLI competition in the future. Hopefully the results of the survey
will serve as a guideline for future UCF USLI teams and allow them to expand on our
activities. We have deemed the project a success because many students voiced a
newfound interest in pursuing an engineering career. Their main interests were
Aerospace/Mechanical Engineering and some who desire to become doctors are
looking into expanding into Biomedical Engineering.
Budget Summary
Item
Price Per
Qty.
Total for Item
SOLLER COMPOSITES
25' of Carbon Fiber Sleeve
$5.70
25
$142.50
[Couplers] 5.0" 12K Carbon Fiber Sleeve x 2'
$6.59
15
$98.85
Heat Shrink Tubing 12’ 5.9” diameter
$6.99
12
$83.88
Car-12K-tow
$26.00
2
$52.00
2 yd of 24K Carbon 24KPL50 (PLAIN WEAVE)
fabric for Hard Backing of Fins
$76.20
2
$152.40
3 yd of 3K Carbon 3K2X2TW50 (TWILL WEAVE)
fabric for Smooth Cover of Fins
$89.85
3
$269.55
13
Fiberglass sleeve 4” diameter Heavy 27'
$5.99
27
Total
$233.03
$799.18
GIANT LEAP ROCKETRY
75mm system starter
$44.50
1
$44.50
[Fiberglass Tube] 3.00" / 76mm Airframe (48" long)
$75.68
1
$75.68
$6.60
3
$19.80
Structural Adhesive Aeropoxy KIT: Quart A + Quart
$42.75
1
$42.75
QUIK-CURE 5min Epoxy
$10.99
2
$21.98
3/8" nomex honeycomb
$19.19
5
$95.95
Megafoam
$23.95
2
$47.90
Mixing set
$6.13
3
$18.39
Nitrile gloves
$0.49
50
$24.50
Mixing cups
$2.12
5
$10.60
Insta-cure thin
$3.99
2
$7.98
Insta cure thick
$3.99
2
$7.98
$11.29
4
$45.16
Tubular shock cord of KEVLAR (1/2")
$3.93
10
$39.30
Giant Leap Swivels: 1500 lb. Test - 1/2" Eyelet
$6.00
2
$12.00
U Bolts - 3/8" Diameter Shaft with 2 nuts & washers
$5.32
2
$10.64
JB WELD
$5.85
1
$5.85
[Centering Rings] 6.00 to 76mm
Parachute Protectors: To 7.5" Airframe
®
Total
$530.96
WILDMAN ROCKETRY
4 Grain Casing P75-4G-CAS
$189.95
1
$189.95
$34.95
1
$34.95
Red Lightning 3 grain 75mm
$189.95
1
$189.95
Launch Buttons for 10/10 rail
$5.00
1
$5.00
one motor spacer
Total
$419.85
WEST MARINE
Epoxy Resin (West Systems 105)
$120.00
1
$120.00
Hardener (West Systems 206)
$45.00
1
$45.00
Pour Stems
$15.00
1
$15.00
Total
$180.00
FIBREGLAST
3 yd package of Release
$19.95
1
$19.95
3 yd roll breather
$16.95
1
$16.95
3 yd vacuum bag
$12.95
2
$25.90
14
5 yd vacuum bag
$17.95
2
$35.90
Spiral Tubing (10 ft. Spool)
$19.95
1
$19.95
Rolls of yellow tape
$7.95
2
$15.90
Vacuum Connectors
$4.95
2
$9.90
Vacuum tubing 20 ft
$29.00
1
$29.00
Total
$173.45
AMAZON
MV80 Plastic Micro Camcorder
$39.00
4
$156.00
4 GB Sandisk Memory Card
$11.90
4
$47.60
Total
$203.60
SPARKFUN ELECTRONICS
High Altitude Sensing Board
$99.95
1
$99.95
Arduino Microcontroller Board
$29.95
1
$29.95
Total
$129.90
OZARK AEROSPACE
Arts TT2 GPS Transmitter (Integrated Wire
Antenna)
Arts RX-900 (Standard Radio)
$450.00
1
$450.00
$270.00
1
$270.00
Total
$720.00
MICRO CIRCUIT LABS
SDL-1 Solar Data Logger
Solar Irradiance Meter
$229.25
1
$229.25
$24.95
1
$24.95
Total
$254.20
HOBBY BOARDS
UV Index Meter
$40.00
1
Total
$40.00
$40.00
PERFECTFLITE
PerfectFlite miniAlt/WD
$99.95
Total
4
$399.80
$399.80
TOTAL COST (Rocket)
$3,850.94
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