Transcript CDR
Biological Acquisition Unit
Team Members:
Fred Avery
Ny ‘Jaa Bobo
Gene Council
Salvatore Giorgi
Advisors:
Dr. Helferty
Dr. Pillapakkam
Outline of Presentation
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Mission Overview
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Objective
Theory
Background / Previous Research
Biological Analysis
Success Criteria
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Project Overview
Design Process
Electrical System
Physical Model
Software Flow Chart
Power System
Components
Filter System
Optical System
Design Compliance
Testing / Testing Equipment
Biological Analysis / Chemical Analysis
Shared Can Logistics
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Schedule
Team Members
Advisors
Part List / Budget Outline
Conclusion
Design
Management
Mission Overview
Objective
• Measure the earth’s magnetic field as a function of
altitude.
• Measure flight dynamics of the rocket.
• Capture biological samples in the atmosphere.
• Identify types and concentration of samples as
function of altitude.
• Measure UV intensity as function of altitude
• Identify UV damaged DNA in samples.
Theory
• Two accelerometers and one gyroscopes will be
used to measure the rocket’s flight dynamics (roll,
pitch, and yaw).
• The magnetometer will measure the strength and
direction of the earth’s magnetic field as a function
of altitude.
• The filtration system will combine passive and active
collection techniques to gather organic and
inorganic material suspended in the atmosphere.
• Spectrometer measures properties of light over a
specific electromagnetic spectrum, specifically
intensity of wavelengths between 200 and 850 nm.
Background
• Biological aerosol defined as airborne solid particles
(dead or alive) that are or were derived from living
organisms, including microorganisms and fragments of
living things.
• Includes bacteria, fungi, viruses, unicellular organisms
• Potential roles of micro-organisms
• Act as cloud condensation nuclei and to participate
in radiative forcing.
• Many airborne micro-organisms likely metabolize
chemical components of aerosols thereby modifying
atmospheric chemistry.
• Some researchers suggest that a self contained
ecosystem might exists at high altitudes.
Previous Research
• Types of species found at high altitudes: bacterial
species Bacillus subtilis and Bacillus endophyticus,
and the fungal genus Penicillium.
• Size of particles: biological aerosol particles range
from 0.2 to 5 μm.
• DNA photolyase, a FAD-containing flavoprotein,
uses light to drive an electron transfer reaction
between the protein and a DNA lesion. The
mechanism by which this transferred electron
repairs the DNA is currently unknown.
Success Criteria
• Acquire specimens in middle atmosphere
o Collect a statistically significant sample to compare to previous
studies.
• Type of samples and their concentration
• Determine altitude where samples were collected
• Spectrometer
o Accurately measure and record UV intensity
o Correlate UV damaged DNA in samples with UV intensity
• Accelerometers and Gyroscope
o Accurately and precisely measure flight conditions
• Velocity
• Spin Rates
• Gravitational Force
• Magnetometer
o Study magnetic field in middle atmosphere.
o Compare experimental magnetic field to actual values .
System Overview
Project Overview
Design Process
Design Sensing Circuit
• Schematics
• Placement on
plates
• Software flow
Test System
• Pressure
• Vibration
• Spin
• Sterilization
• Data Storage
Acquire Material (Sensing
Circuit)
• XY-Axis accelerometer
• Z-Axis accelerometer
• Gyroscope
• Voltage Regulators
• Microprocessors
• Magnetometer
• Spectrometer
• Servo Motors
Assemble Design
• Construct plates
• Secure components
on plates
• Mount Cosine
Corrector
Acquire Material
(Passive System)
• Filters
• Filter Canister
• Ball valves
• Tubing
Test Components
• Sensors
• Processors
• Filter System
• Spectrometer
Electrical System Block Diagram
Physical Model
Software Flow Chart
Initialize System
Start timer for shutting down system
(900 sec)
Sample Sensors (I2C, SPI, USB, and
analog pins)
Initialize System
Start timer for opening valve (36 sec)
First Timer
Finished
Open Valve
Interrupt
from
Timer
Write sensor data
Start timer for closing valve (300 sec)
Second
Timer
Finished
Write sensor data
Close Valve
Shut Down System
Main Microprocessor
Second Microprocessor
Power
Basic System Requirements
• Main Microprocessor – 90 mA @ 3.3 V
• Second Microprocessor - 90 mA @ 3.3 V
• Magnetometer – 0.9 mA @ 3.3 V
• Gyroscope – 3.5 mA @ 5 V
• XY-axis accelerometer – 15 mA @ 6 V
• Z axis accelerometer – 2.5 mA @ 6 V
• Spectrometer – 0.6 A @ 5 V
Sources
• Voltage regulators will be
used to maintain the proper
amount of power for each
sensor
• Five 9 V batteries will power
system
Components
Magnetometer
• Power: 2.5 to 3.3 V
• Field Range: +/- 8 Gauss
• Current: 0.9 mA
• Bandwidth: 10 kHz
• Weight: 50 mg
• I2C interface
Gyroscope
• Power: 5 V
• Range: +/- 20,000 °/sec
• Current: 3.5 mA
• Bandwidth: 2 kHz
• Weight: 0.5 g
• Output voltage proportional
to spin
Components
XY-axis Accelerometer
• Power: 3.0 to 3.6 V
• Range: +/- 37 g
• Current: 15 mA
• Bandwidth: 400 kHz
• Serial Peripheral Interface (SPI)
Z-axis Accelerometer
• Power: 3.3 to 5 V
• Range: +/- 70 g
• Current: 2.5 mA
• Bandwidth: 22 kHz
• Output voltage proportional
to acceleration
Components
Primary Microprocessor
Flash Memory: 512K
RAM Memory: 128K
Operating Voltage: 3.3V
Operating Frequency: 80 MHz
Typical Operating Current: 90 mA
I/O Pins: 83
Analog Inputs: 16
Analog Input Voltage Range: 0V to 3.3V
DC Current Per Pin: +/- 18 mA
USB 2.0 Full Speed OTG controller
I2C and SPI interfaces
Components
Second Microprocessor
Flash Memory: 128K
RAM Memory: 16K
Operating Voltage: 3.3V
Operating Frequency: 80 MHz
Typical Operating Current: 90 mA
Analog Input Voltage Range: 0V to 3.3V
I/O Pins: 42
Ethernet Shield
DC Current Per Pin: +/- 18 mA
Onboard microSD card reader
Communicates with SD card using the SPI bus
Will connect with our primary processor
Operating Voltage: 5 V
Filter System
Design
• Connects to two ports: Static and
Dynamic
o Dynamic port draws in samples
o Air flow exits through the static
port
• Contains four filters in series
o Filters are decreasing in size from
5 to 0.2 μm
• Filter system terminates with NPT
connector at each end
Testing
• All parts must be autoclave-able
• Two filter systems will be
constructed
o One will be included one
rocket
o Other kept on ground
o Results compared
Mass Flow Rate
• The mass flow rate is expected
to be about 5.3×10-6 kg/s
Exposure Time
• System will open at 30 km and
close at 30 km
• Particle sizes ranging from 0.2
to 5 µm
• Based on previous data we
estimate the filter system will be
open for 5 min
Filtration System
Optical System
Grating Specifications
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Groove Density: 600 mm-1
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Spectral Range: 650 nm
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Blaze Wavelength: 300 nm
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Best Efficiency (>30%): 200 –
575 nm
Optical Resolution
• Goal of approximately 1.0 nm
• Resolution = Dispersion * Pixel Resolution
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Dispersion = Spectral Range / Detector Elements
Detector Elements = 2048
Pixel Resolution determined by entrance slit size
• Entrance Slit of 25 microns was chosen
which results in a 4.2 pixel resolution
• Resolution = (650 nm / 2048 pix)*4.2 = 1.33 nm
Optical System
Optical Bench
1) Fiber optics connector
2) Fixed entrance slit of 25 microns
3) Longpass absorbing filter
4) Collimating Mirror
5) Grating with Groove Density of
600 lines/mm
6) Focusing Mirror
7) Detector collection lens
8) 2048 element Linear CCD Array
9) Longpass order-sorting filter
10)UV detector lens
The Longpass absorbing filter
(3) is not included in our system.
Optical System
Cosine Corrector
• Couples to optical fiber for spectral
intensity measurements
• Wavelength Range: 200 - 1100 nm
• Field of View: 180°
• Diffusing Material:
Polytetrafluoroethylene (PTFE)
• Numerical Aperture (NA) of lens
must match that of fiber optics
cable, which is 0.22.
• Calculated using: NA = (nD) / 2f)
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n = index of refraction
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f = focal length
Design Compliance
• Final mass must be 6.55 lbs
o Total weight of sensors and spectrometer is less than 3 lbs
o Projected filtration system weight is less than 2 lbs
o More weight will be added once we are able to fully
assemble the system
• Payload Activation
o G-switch
• Center of Mass
o Solid Works projection shows this constraint will be met
o Once additional weight is added this must be recalculated
Testing
Mechanical
• Drag Force
• Test to see if filtration system
can withstand air flow
• Low Pressure
• Simulate depressurization of
canister
• Test to see if entire system
functions at low pressures
• Stability
• Make sure entire canister
functions under range of spin
rates and impulses
• Determine structural integrity of
plates and sensor mounting
Optical
• Measure light of known intensity
Biological
• Test to see if filtration system can
be properly sterilized
• Test to see if filtration tube can be
completely sealed
• Determine if filters can remain
sterilized for one week
Electrical
• Sensors
• Test accuracy
• Functioning Properly
• Data
• Test processor is properly
handling incoming data
• SD Card / Reader properly
storing
• Power
• Test to see if entire system is
fully powered during flight
Testing Equipment
The following testing equipment will be used
• Vibration Table
• The table at Temple will not match expected impulses
• Air Foil
• Vacuum Pump
• Supplied by the Biology Department
• Spin Table
• Neither Temple nor Drexel University own a spin table that will spin at 5 Hz
• We will construct our own table which will operate between 0 and 5 Hz
and support a 20 lbs canister
• Autoclave
• Supplied by the Biology Department
• Will not kill any DNA present in our filter system
• Mock Canister
• Will be built to simulate the optical port in canister
• Fluorescent light and Sun light will be measured
Biological Analysis
• DAPI (type of microorganisms)
o DAPI (6-diamidino-2-phenylindole) is a stain used in fluorescence
microscopy. DAPI passes through cell membranes therefore it can be
used to stain both live and fixed cells.
• BRDU (type of microorganisms)
o Bromodeoxyuridine (5-bromo-2-deoxyuridine) is a synthetic nucleoside
that is used for detecting actively dividing cells.
• Genetic Sequencing (type of microorganisms)
o Determines the number of nucleotides in sample’s DNA: adenine,
guanine, cytosine, and thymine
• Scanning Electron Microscope (concentration of
microorganisms)
o Scans the sample and re-generates image to be analyzed, i.e. structural
analysis of microbes
Chemical Analysis
• A research team at Temple University is working to
understand the unknown mechanism of DNA repair by
DNA photolyase.
• Group studies this mechanism by
o Use of ultra fast laser and biochemical techniques
o Exploring the details of substrate binding using fluorescence reporter, two
photon excitation techniques, and single molecule microscopy
• Once samples are identified through biological analysis
they will be handed over for chemical analysis
• Team proposes to compare samples to similarly
damaged DNA found in extreme terrestrial
environments
Shared Can Logistics
• Sharing canister with Drexel University
• Communication has been opened up between the teams
o Both teams expect to use half the canister space and weight
• Drexel’s proposed experiments will not effect ours
• Close proximity will allow us to integrate entire canister prior to
flight
• Drexel’s team will be using vibration table at Temple
Management
Schedule
Goals:
December
January
Finalize Software
Construct Spin Test Platform
Construct Filtration System
Spin Tests
Machine canister plates
Sterilization Tests
Construct Payload
Construct Spin Test Platform
Vibration Tests
Spectrometer Tests
Build mock canister
Important
Dates:
December 1: CDR
Teleconference
January 1: Final Down Select Flights Awarded
Team Members
Fred Avery (ME)
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Filtration System
Center of gravity testing
Mass Flow Rates
Spin rate testing platform
Gene Council (EE)
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Hardware
• Magnetometer
• Accelerometers
• Gyroscope
Programming
Ny ‘Jaa Bobo (EE)
• Hardware
• Magnetometer
• Accelerometers
• Gyroscope
• Power
Salvatore Giorgi (ECE)
• Team Leader
• Spectrometer
• Microprocessor
• Data Acquisition
• Filtration System
Parts List / Budget
Parts
Manufacture
Cost
Quantity
Payload Canister
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$7,000
1
Pic32 chipKIT Max
Digilent
$49.50
1
chipKIT Uno32
Digilent
$29.95
1
Magnetometer
Sparkfun
$19.95
1
G-Switch
Digikey
$12.95
1
SD card 2 GB
SanDisk
$27.99
1
Arduino Ethernet Shield
Sparkfun
1
Filter Paper
Millipore
$39.95
Supplied by Bio
Department
Filter canister
Millipore
$388.00
4 types
1 pack = 8
canisters
Parts List / Budget
Parts
Manufacture
Cost
Quantity
Gyroscope
Analog Devices
$90.00
1
XY-axis accelerometer
Analog Devices
$99.00
1
Z-axis accelerometer
Analog Devices
$75.90
1
Spectrometer
Ocean Optics
$3334.00
1
Fiber Optics Cable
Ocean Optics
$184.00
1
Cosine Corrector
Ocean Optics
$150.00
1
Spectroscopy Operating Software
Ocean Optics
$199.00
1
Polypropylene
Ball Valve
Cole-Parmer
$8.00
4
Standard Servo motor
Parallax
$12.99
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Advisors
Electrical
Dr. John Helferty
Department of Electrical and
Computer Engineering
Mechanical
Dr. Shriram Pillapakkam
Department of Mechanical Engineering
Biological
Dr. Erik Cordes
Chemical
Dr. Robert Stanley
Department of Biology
Department of Chemistry
Conclusion
• Concerns
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Properly counting samples as function of altitude
Properly sterilizing and maintaining sterilization of the filtration system
Autoclave does not kill DNA
Correcting for any stray light that might enter our cosine corrector
• Major Risks
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Failure of filter system leading to depressurization of canister
• Recently Finished
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Spectrometer design completed
Ordered second microprocessor, ethernet shield, and spectrometer
• Future Plans
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Purchase and machine plates
Write library for USB interface
Order ball valves and tubing for filter system
Test servo motors available in lab with ball valves
Continue programming processor
Construct spin test platform and mock canister
Begin tests