Minnesota Sound Wreckers
Conceptual Design Review
University of Minnesota
Alexander Richman
Jacob Schultz
Justine Topel
Will Thorson
9/29/2011
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CoDR Presentation Contents
• Section 1: Mission Overview
– Mission Overview
– Theory and Concepts
– Mission Requirements (brief, upper level)
– Concept of Operations
– Expected Results
• Section 2: Design Overview
– Design Overview
– Functional Block Diagrams
– Payload Layout
– RockSat-C 2012 User’s Guide Compliance
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CoDR Presentation Contents
• Section 3: Management
– Team Organization
– Schedule
– Budget
– Mentors (Faculty, industry)
• Section 4: Conclusions
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Mission Overview
• The purpose of this project is to develop
a mechanical and electrical design for
removing rocket noise that gets
transferred to the test chamber.
• The method to be used is active noise
cancellation with mechanical isolation of
the system.
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Mission Overview
• Our hypothesis is that active noise
cancellation will reduce rocket engine
noise by at least 90%.
• It is possible that experiments done on
sounding rockets will be noise sensitive
and would greatly benefit from noise
cancellation.
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Mission Overview: Theory and Concepts
• Noise cancellation requires some
knowledge of acoustic wave propagation
and also signal processing techniques.
• We need to measure the signal and
invert it, while amplifying our output
such that we can cancel the signal but
not create a larger problem.
• What other research has been performed
in the past?
– Results?
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Mission Overview: Mission Requirements
• We want to cancel the noise and prove that our system
works
– We measure the input signal in the experimental chamber
and process that in order to output the inverse into the same
chamber
– We take input data in the control chamber
– Afterwards, we compare the input at the microphone of the
control and experimental chambers
• Minimum success criteria
– Take data on input of the experimental chamber
– Output a signal from the speaker in an attempt to cancel the
noise
– Structure maintains full integrity for the duration of the
flight
crestock.com
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Expected Flight Time
Altitude
t ≈ 1.7 min
Altitude: 95 km
t ≈ 1.3 min
Apogee
t ≈ 4.0 min
Altitude: 75 km
t ≈ 2.8 min
Altitude: 95 km
Altitude: ≈115 km
t ≈ 4.5 min
Altitude: 75 km
End of Orion Burn
t ≈ 0.6 min
t ≈ 5.5 min
Altitude: 52 km
t = 0 min
Chute Deploys
-All systems on
t ≈ 15 min
-Begin data collection
Splash Down
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Noise Cancellation TimeLine
1. Launch
• Data collection begins
• The system begins to cancel all noise
2. Initial Thrust Completed
• We expect to see our best results from
this point on
3. Landing
2
• At the landing, our circuit is still
functioning
• We don’t want to overwrite any data
collected during flight.
1
3
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Mission Overview: Expected Results
• We expect to be successful reducing the
overall power of the wavelength spectra
between about 50Hz and 20kHz
• This means a reduction in amplitude at
most of the frequencies within this
range.
– We are planning on using a middle range
speaker, and thus will maybe see more
response from 1kHz to 10kHz.
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Design Overview
• We hope to use the power supply and data
logger from our previous flights
– We may need to put more batteries in the power
supply in order to get enough amplification in the
speaker
• We need a microphone, speaker and DSP
capable of doing all this
– The microphone needs to be small and capable of
taking the force of the initial launch.
– Same goes for our speaker, which will hopefully
be efficient enough that we can drive it fully with
our power supply.
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Functional Body Diagram
Power
Data
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Example FBD – mechanical/system (rough diagram)
Dummy
speaker
Control
chamber
Electronicsp
o
w
e
r
Test
chamber
speaker
Data recording
Electronics –
controlling sensor
(mounted to plate)
plate
microphones
Mounts to lid of
canister
Mounts to base of
canister
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Design Overview: Payload Layout
• The structure will contain two sealed
chambers as well as an area to mount the
electronics and power supply
classymommy.com
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Design Overview: RockSat-C 2012 User’s Guide Compliance
• Predicted mass- we expect the electronics to
weigh about 2 lbs. and the structure made
out of aluminum should weigh about 10 lbs.
the entire canister without balancing
weights should weigh approximately 19 lbs.
the last pound will be weights attached
within the structure to ensure a center of
gravity within the requirements
• The experiment will employ use of the
entire can.
• All systems activate upon connection with
the rocket using the rocket activation wire
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Management
• Team leader: Jacob Schultz
• Aerospace Team: Jacob Schultz, Justine Topel
• Electrical Team: Alexander Richman, Will
Thorson
• Faculty Advisors: Professor Ted Higman,
ECE, University of Minnesota
Professor William L. Garrard, AEM,
University of Minnesota
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Management
• September-Oct 15th
– Research requirements and preliminary design
– Look up what components need to be purchased
• Oct 15th-Nov 15th
– Work final design including solid works drawings
and electronics drawings
– Ensure no issues with design
• Nov 15th-Nov29th
– Prepare CDR make sure everything checked
multiple times and ready for submission
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Conclusion
• Our Mission is to employ active noise
cancellation onboard a rocket
• From this point we plan on looking at the
exact components necessary and
dimensions in order to make a more
finalized design
– We are going to further investigate how to
implement noise cancellation best and ways to
configure the electronics onboard
– We are ready to start looking at subsystems
and lower level designs at this point
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