Title: Critical Design Review
1Critical Design Review
- West Point-Beemers SLI Vehicle and Payload
Experiment Criteria
2Mission Statement
- Experimental Test of Boyles Law with a 1 mile
high power rocket launch - Requirements
- Launch vehicle to an altitude of one mile
- Collect useful scientific data
- Successfully recover rocket
- Accomplish all other goals of the NASA SLI
program - Mission Success Criteria
- Launch vehicle to an altitude of one mile
- Collect useful scientific data
- Successfully recover rocket
- Accomplish all other goals of the NASA SLI
program
3Design at System Level
- Design Review at a system level
- A. Updated Drawings and Specifications of
systems - I. Recovery
- Recovers rocket safely in compliance with NFPA
1127. See recovery subsection - II. Payload
- Accomplishes scientific goal of flight, details
in payload section - IIV. Electronics
- Perfectflite MAWD Drogue charge at apogee, main
charge at 500 - Ozark Aerospace ARTS 2.0 Drogue 1 second after
apogee, main charge at 450 - BeeLine GPS in booster section
- Standard BeeLine for backup in the payload
section - Data Recorder
- Remote Launcher
- IV. Stability/Booster
- Three ¼ Plywood fins built into an interlocking
structure that makes up the whole booster.
Enclosed in a tube that is removable. - V. Ignition
- Remote launch system.
- 9.07 x 10 -9 percent chance of being
inadvertently activated by another user of the
same type of system. - Operates on 433.92Mhz
4Pictures
- Electronics, Remote Launch System
5Testing
- 3.71 Scale Test Flight, 12-17-06, success by all
measures.
6Testing
- Fins Structure (Actual will only have 3 fins)
7Testing
8Preliminary Motor Selection
- Animal Motor Works K975. Extremely unlikely that
a smaller motor will be selected, 75mm and L
motors cannot be used for various reasons
9Demonstration of vehicle meeting all system level
functional requirements
- Current analysis and tests that have been
performed on the booster, electronics and
recovery sections show that all systems function
as intended and as required to achieve mission
success.
10Relation of approach to workmanship and mission
success
- Care to ensure mission success will be in mind at
all times during construction, testing, prepping
and flying. Sloppy jobs and rushed work will not
be accepted and will be redone until it is
acceptable to achieve mission success.
11Additional testing to be performed
- Ejection charge and parachute deployment tests
- Confirmation of the inability of the radio
controlled ignition units capability of being
inadvertently actuated - Ground tests of all electronics before flight
- Possibility of functional tests on motor igniters
(tube representing motor core and nozzle with
pressure and temperature sensors) - CP/CG relationship confirmation with fully loaded
rocket - Fox Hunt with trackers
- Simulate to the best of our ability the flight
loads on the nose, body and fins that the vehicle
will see in flight (apply estimated forces to
proper areas) - Full scale flight test with all systems
operational
12Status and plans of remaining manufacturing
- Complete final booster unit and electronics bay.
- Paint rocket
- Install all electronics and science
13Integrity of design
- A. Fin shape and style for mission
- 1/4 plywood fins of similar size have flown to
the speeds and experienced the loads that will be
placed on our fins during flight. No concerns are
foreseen - B. Proper use of structural elements
- The been reviewed by engineers and the feedback
provided was that 1/8 plywood could be used for
everything but the fins themselves. Due to
material availability, 1/4 plywood will be used
throughout and will be sufficient for the flight. -
14Integrity Of DesignContinued
- C. Proper assembly procedures, attachment and
alignment, solid connection points, proper load
paths. - The precision fit interlocking structure used
throughout most of the vehicle automatically
align when assembled. TiteBond II, a type of
alphaic resin, will be used for all wood to wood
and wood to cardboard connections. These are the
only type of glue connections in the rocket, and
the use of wood glue on precision fit parts is
nearly foolproof. The loads from the motor thrust
will be distributed from the thrust ring on the
motor, to the aft ring in the fin unit, to the
body tube and truss structure, to the upper body
tube and electronics bay, through the body tube
to the nose. - D. Motor mounting and retention
- An internal masking tape ring will be used to
retain the motor. The motor has no way to move
within the rocket unless the fins, body tube and
lower centering rings all fail, which is highly
unlikely. - E. Status of verification
- The Perfectflite MAWD will be used to verify the
altitude. It will be operational for flight as it
is essential to vehicle operation.
15Safety And Failure Analysis
16Recovery Subsystem
- Kevin Rich, a licensed parachute rigger for
man-rated parachutes will be assisting us with
the recovery of the vehicle. With a final vehicle
weight of about 21 pounds ready to fly, a
parachute that can handle that weight and still
recover at a safe rate of under 20 feet per
second will be required. - Due to their extreme reliability and durability,
a Rocketman R14-C, which can handle rockets from
20-35 pounds, has been chosen. A Rocketman R3-C
will be used as a drogue at apogee and the main
R14 will deploy at 500 AGL. The MAWD and ARTS
will fire independent ejection charges housed in
PVC caps to separate the body sections and allow
the parachutes to come out. Calculations and
tests will be done to determine the mass of the
4fg black powder required to reliably deploy the
parachutes. - www.the-rocketman.com
17Recovery SubsystemContinued
- The R3 will be attached to approximately 30 feet
of 9/16 tubular nylon climbing webbing which
will be attached to an eye-bolt in the top of the
motor and a eye-bolt on the bottom of the
electronics bay. A water knot with no quick links
will be used for attachment. The main parachute
will be attached in a similar manner using 20 of
9/16 webbing attached to the eye-bolt on the top
of the electronics bay. No quick links will be
used in any part of the system as they only add
more failure points and more things to forget. - The R14 will be packed in a custom made
deployment bag that the team will work on with
Kevin Rich. A small pilot parachute is likely to
be used to pull the bag out of the tube and
deploy the parachute. At this time, it is
currently unknown whether or not the bag, pilot
and nose will recover attached to the top of the
canopy or separately.
18Mission Performance Predictions
- Criteria Propel the vehicle to 1 mile (5280
feet) in a strait, stable flight that does not
put forces on the vehicle that the vehicle cannot
handle and successfully recover the vehicle
within the fields perimeter without violating
the FAA waiver.
19Flight Profile Simulations
- Maximum altitude 5760 Ft.-K975 in no wind
- Maximum altitude 5710 Ft.-K975 in 10 mph wind
- Maximum altitude 5598 Ft.-K975 in 20 mph wind
20Validity of Simulations
- The simulations show that ample extra altitude
will be achieved unless the vehicle is more than
3 pounds overweight. Test flights with the actual
vehicle will be used to tune the altitude and
make sure that the Huntsville flight will achieve
nearly exactly 1 mile - A static margin of 1.67, with the CG at about 57
and the CP at about 66, is sufficient for stable
flight
21Stability
22Payload Integration
- A. Integration plan
- The electronics/payload bay is specifically
designed for easy integration of the payload and
deployment electronics. The data collection
device will be simply bolted to one of the 3
trusses that span the length of the payload bay.
The 9v battery that it will run on will also be
mounted with zip-ties to a truss. The data
collection tubes will slide in precision cut
holes in the two rings inside the bulkhead. To
slide them in, one of the bulkheads on either end
of the electronics bay will be removed by
removing the eye-bolt on that end. This will
expose the holes that the tubes slide into. They
will then be slid in, secured with rings of
masking tape to prevent them from sliding and the
bulkhead and the eye-bolt will be replaced. - B. Interface
- The final outside diameter of the data collection
tubes has not been finally determined at this
point however it is known that it will be below
1.5. 4 1.5 holes will easily fit in the
electronics bay as shown in the picture earlier.
The diameter of the holes in the final bay will
be determined by using a caliper to measure the
O.D. of the data collection tubes and put that
value in AutoCAD so that the parts can be cut out
accurately with the water cutting machine.
23Payload IntegrationContinued
- C .Compatibility
- The separate parts will be separated by 1/4
trusses and should not pose any problems to each
other. The ARTS will have aluminum foil to
protect it from RF interference from the Beeline
Tracker. Experience has shown that in close
proximity they will interfere with each other and
cause the ARTS to operate improperly. Other
incompatibility issues are not expected due to
previous experience - D. Integration
- No simpler way of integrating the payload has yet
been found. If any method is found that makes it
easier to integrate the payload, consideration of
a design change may be made, however, at this
point, that is unlikely.
24Launch Concerns and Operation ProceduresVehicle
Prep
- Unpack shipping containers and verify packed
contents are present. - Inspect all parts for damage. If damage is found,
fix it if possible. - Assemble motor according to manufactures
instructions. - Assemble electronics and payload bay
- Set up lower electronics bay
- Prep and install motor
- Pack Recovery System
- Slide lower tube onto booster section and secure
with screws. - Slide upper tube onto coupler section of booster
and secure with shear pins. - Install rail buttons
- Give rocket final visual inspection and resolve
any problems that may exist. - Verify from the Range Safety officer that the
field conditions still meet acceptable launch
criteria.
25Launch Concerns and Operation ProceduresLaunching
- Set up launch pad and launch controller.
- Clear dry grass or other materials within the
radius required by NFPA 1127. - Confirm that electronics (except tracking devices
and the data recorder) are turned off. - Bring rocket out to the launch pad.
- Load rocket on launch rail.
- Power-up electronics
- Confirm continuity on all 4 altimeter output
channels and all 4 recording input channels. Also
confirm tracking signals from both trackers. - Verify launch angle will place recovered rocket
within the launch field. Adjust angle if needed. - Confirm all near-pad video recording devices are
ready for flight - Power up remote launching device and confirm
continuity from launch control. - Clear all non-essential personnel from the safety
radius around the launch pad. - Install igniter into motor. Confirm igniter is
all the way to the top of the motor to insure
proper motor ignition. - Confirm continuity on all channels and trackers
one final time. - Retreat to launch control area.
- Alert everybody of the impending launch and make
sure proper safety radius around the vehicle is
clear. - Check continuity. Turn of continuity checker
after check is done. - Arm launcher.
- Count down from 5.
- Launch vehicle.
26Launch Concerns and Operation ProceduresPost
Flight-Operations
- Track rocket using primary GPS tracker and find
rocket location. If GPS tracker is not sending a
correct signal, use the backup tracker. - Go to location of vehicle
- Approach vehicle perpendicular to center tubing
section - Disarm all electronics. (Tracking and data
recording electronics can be left on.) - Carefully confirm that all ejection charges have
fired. (Use a mirror on a stick with a flashlight
to look into tubes. Do not put face or other body
parts over ends of tubes prior to confirmation). - If charges have all fired, disconnect recovery
system. Transport the rocket back to the launch
area. - Remove and clean motor case when it has cooled
down. - Unscrew and remove airframe tubes from
electronics bay. - Download flight and experiment data to laptop
computer. - Turn off GPS and backup trackers and any other
electronics that have not yet been turned off. - Remove any other non-shippable rocket components.
- Pack rocket back in shipping container for trip
home.
27Safety And Environment
- Andrew is our safety officer. He has experience
in risk mitigation in complex, high risk high
power rocket construction and flight. All
participants will be required to show the
necessary knowledge of our safety plan.
28Failure Modes
29Prevention of Inadvertent Activation of Remote
Control Devices
- Devices will utilize shunts and switches that
break the circuit to prevent current flowing to
igniters when device isnt armed. - Devices will not be able to be actuated unless a
unique 60ms code is received. - 9 x 10 -9 chance of inadvertent activation by
a non involved part
30Personal Hazards
31Personal HazardsContinued
- Always wear safety glasses when dealing with
rocket parts containing small hardware or
pyrotechnic charges. - Never look down a tube with live pyrotechnic
charges in it. - Always point rocket and pyrotechnic charges away
from body and other people. - Avoid carrying devices that have live electrical
contacts (radios, cell phones, etc.) while
prepping live pyrotechnic charges. - Never arm electronics when rocket isnt on pad
unless the area has been cleared and everyone
knows that pyrotechnic continuity checks are
being done. - Always follow the NAR/TRA safety codes.
- Always follow all applicable local, state and
national laws and regulations. - Only the Level 2 certified mentor may handle the
motor (CPSC regulations). - Do not allow smoking or open flames within 25
feet of the motor or pyrotechnics. - Avoid horseplay and idle conversation, focus on
properly completing the task at hand. - Make sure the checklist is followed and all steps
are completed properly in a though, workmanlike
manner to assure mission success. - Since the motor for the flight utilizes snap
rings to retain the ends of the motor, care must
be taken when installing and removing snap rings.
Snap rings can be sent flying at high speeds in
unpredictable directions even if reasonable care
is being taken, thus, all personnel within 25
feet of a snap ring installation or removal
procedure will be required to wear safety glasses
or move out of the area and keep eyes turned away
from motor.
32Environmental Concerns
- All waste materials will be disposed of using
proper trash receptacles, biodegradable and flame
resistant recovery wadding will be used.
Practice launches will only occur with local fire
department permission if dry grass conditions
exist. Bureau of Land Management regulations
will be followed when doing test launches on BLM
land. Solid rocket motor manufactures
instructions will be followed when disposing of
any rocket motor parts. Consideration of
environmental ramifications will be made
regarding applicable activities.
33Payload Criteria
- We have determined after continued testing that a
syringe will not provide a sufficient force to
push a liner potentiometer. That moves us to our
third measuring design. We will use a strain
gauge on a flexible diaphragm at the end of our
gas sample tubes. This device will have to be
calibrated for pressure to resistance ratios, and
we will be testing the ideal gas law (PVnRt)
with changing pressure as our variable instead of
changing volume. Strain gauges are on order and
should be delivered next week. Until then we are
testing with a disassembled digital scale. We
are very interested in seeing the effects of the
launch on the flexible diaphragm end and gauge.
We will use 12 X 1 pvc tubes as our sample
chambers and rubber sheeting as the diaphragm
34The custom data recorder!
35Specs on recorder
- Sample rate 20Hz
- Channels 6 analog
- Memory 262144bits, 32768bytes, 16384samples
- Sample size 12bit
- Recording time 136.5 seconds
- Size 1x2in
- Power requirement 5.5V-12V(9V nominal)
- Processor Microchip PIC16F88 (see
www.microchip.com) - Oscillator speed 8MHz
- Download connection RS232 serial at 9600baud
- Recording start trigger Break wire, start on open
36Payload Concept Features and Definition
- Proposed science payload will test different
gasses to confirm that they behave according to
Boyles Law. By testing various gasses in the
range of pressures and temperatures found in a
rocket flight to 1 mile, we hope to accomplish
this. - We havent seen any other teams attempt a science
experiment like this. We feel that because of
that, it is unique and that it will provide a
suitable challenge to us for this project. - The problems that we have encountered with
measuring the changes in the gases has shown us
that there is considerable challenge in this
project
37Science Value
- Comparison of theoretical calculations of gas
behavior to results of launch test will confirm
success of the experiment. Variables such as
barometric pressure and temperature on launch day
will need to be recorded and factored into the
projected results of the experiment. Projected
results will be calculated using proven behaviors
of the various gasses used in the experiment.
Matching results between the collected data and
calculated projection will determine success of
the flight. The variables would be the
temperature and pressure of the gas and the
original amount of gas on ground level will be
the control. Our predicted data will be graphed
against our actual results after the flight using
a spreadsheet program.
38Safety and Environment
- Andrew is our safety officer. Andrew has more
experience with rockets than anyone else on the
team. - Our current main concern is in the attachment of
the strain gauges to the diaphragm. We will have
to calibrate each tube individually to maintain
accuracy. We will mount our tubes with the
strain gauges facing to the top of the rocket so
inertia does not rip them off during launch.
39Outreach
- We have had our Rocket display at the local
library for the month of December. - We are teaching rocketry to the 4-H club in
Beemer on January 27th. - We will be discussing our rocketry and our
project with the West Point Optimists club on
February 14th - We are sharing some resources with the Benson SLI
team
40Activity Plan
- Budget 2,750. We hope to get a local grant to
cover the extra expenses or raise the money
elsewhere. - Timeline
- First test flight preliminarily planned for Feb.
24 - Continuing to order parts and do construction as
things are finalized - Flight Readiness Review
- Full timeline in CDR Document
41Summary
- In summary we feel that we are still on track
both budget and time wise for successful
completion of this project.