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OZONE MEASUREMENTS:A LAACES PAYLOAD PROPOSALBY TEAM CHINESE BANDITS
Zach BaumHarry Gao Ryan MoonJohn ReeksSean Walsh
MISSION GOAL
The mission goal of this payload is to measure the concentration of Ozone (O3) as a function of Altitude and Time
PREVIOUS ATTEMPTS BY OTHER TEAMS
Previous Team Reason for Failure
Proposed Fix
Avengers Phase 2 Blown EEPROM failure to calibrate sensor
Allow more time for testing and double check vital electronics as part of preflight checklist.
Avengers Phase 1 Unable to keep sensor in operating range. Wiring issuing with circuit.
Design system with the ability to increase temperature(heater). Have guidelines to follow for wiring circuits to ensure proper debugging.
OBJECTIVES
Science Objectives The objective of this project is to measure the
concentration of Ozone (O3) focusing on an altitude from 10 km to 50 km from sea level
Measure the concentration of ozone with respect to time of day
Technical Objectives Produce readable measurements on ozone
concentration To keep sensors within operating range Record collected data for retrieval
SCIENCE BACKGROUND
WHAT IS OZONE?
The Ozone layer is located in the lower portion of the stratosphere, from approximately 10 km to 50 km above ground
SCIENCE BACKGROUNDWHY IS OZONE IMPORTANT
Ultraviolet radiation is a major source for destroying and creating stratospheric ozone
*Team Avenger 2010-2011 CDR presentation
REQUIREMENTS
Science Requirements Shall measure ozone concentration as a function of
altitude and time Technical Requirements
Temperature in the BalloonSat shall be kept within the operating range of onboard sensors and electronics
Ozone shall be measured as a voltage coming from the sensor
The measurement of ozone shall be recorded and time stamped in order to calculate altitude
PRINCIPLES OF OPERATION
Measured voltage is a function of Ozone concentration
Two choice of implementation Potassium Iodide Sensors (KI)
Reacts with the ozone to generate a small current Liquid form (mixing chemical) Led to many problems including leaks, spills, and
short circuits Indium Tin Oxide sensor has variable
resistance based on Ozone and NOx concentration More accurate than KI sensors because it utilizes a
metal-oxide compound.
SENSORS AND ELECTRICAL
ITO detects Ozone Concentration
Thermistor measures temperature inside payload Used to regulate temperature
Balloon Sat Board 9 Volt board Records and processes input data
Power Supply Lithium batteries connected in parallel
SENSOR INTERFACE
CONTROL ELECTRONICS
Data Data
Power
POWER
POWER SUPPLY
*Data from previous project by Avengers group. (CDR)
Consumer Consumption Rate
Ozone Sensors(per sensor)
10 mA 40 mAh
Thermistor 5 mA 20 mAh
Heater TBD TBD
Balloon Sat 53 mA 212 mAh
Total Greater than 68 mA
Greater than 272 mAh
PROJECT MANAGEMENT
Meetings outside of mandatory meetings Monday, Wednesday: 6:00 PM Tuesday, Thursday: 5:30 PM
Internal deadlines set every Monday Meetings monitor task progress
MECHANICAL DESIGN
External Structure ¾ inch thick insulating foam Hexagonal shape 2 vertical holes 17 cm (6.7 in) apart through
opposite walls for interface to LaACES payload strings
Internal Structure Brace board used to carry and support internal
components Light weight
ITO will be mounted on a foam panel
WEIGHT BUDGET**
Payload has 500 g mass limitation
+/- 48
WEIGHT BUDGET (CONT.)
Possible improvements:
A smaller battery can be used -50g +/- 20
The amount of wire may be reduced -20g +/- 10
The foam width may be reduced from ¾ inch to ½ inch
-35g +/- 20
Adjusted Total: 425g +/- 56
ORGANIZATIONMember’s Name
Title Major Responsibility
Testing/Calibration Prototyping Documentation
Zack Baum
Project Manager*
Communication between team and staff, task assignment, progress tracking
Mechanical Mechanical Managerial/ Managerial
Sean Walsh
Mechanical*
Mechanical Design
Mechanical Mechanical Mechanical
Harry Gao Electrical*/ Software*
Electrical and Software design
Electrical/Software Electrical/ Software
Electrical/Software
John Reeks
Electrical Electrical Design
Electrical Electrical Electrical
Ryan Moon
Software Software design Software Software Software
RISK ANALYSIS
*based upon Avengers Phase 1
CONFIGURATION MANAGEMENT
Leads present prototypes two weeks prior to Pre-CDR
Each lead is responsible for completion of tasks Documentation Research Design
Manager is responsible for monitoring tasks and deadlines
STAFFING PLAN
Task Category Project Lead
Project Management Zach Baum
Science Requirements John Reeks
Electronics Harry Gao
Flight Software Harry Gao
Mechanical Sean Walsh
Integration Ryan Moon
System Testing Sean Walsh
Calibrations Harry Gao
Data Processing and Analysis John Reeks
Documentation Ryan Moon
TIMELINE OF MILESTONES
TIMELINE OF MAJOR TASK CATEGORIES
COSMIC RAYS:A LAACES PAYLOAD PROPOSALBY TEAM CHINESE BANDITS
Zach BaumHarry GaoRyan MoonJohn ReeksSean Walsh
MISSION GOAL
The goal of this project is to create a payload that will measure the flux of cosmic radiation as a function of altitude.
ASSESSMENT OF PREVIOUS FLIGHTS
Group Payload Summary What needs improvement Possible Solutions
Team Flux2002-2003
Compared change in air density to radiation
counts
Only radiation counts were taken. Flux should be taken for increased
understanding
Radiation counts should be taken over a known
area and field of view to determine flux
Team GR22005-2006
Tried to determine the change in flux of cosmic
radiation and gamma radiation with altitude using Geiger-Mueller
sensors
The Geiger-Mueller sensor coated with lead
lost function at low temperature
Reduce focus of measurement to
ionizing particles and use sensors with less
risk of failure
Team Cosmic2009-2010
Determined the flux of cosmic radiation using dual scintillators and
photomultiplier tubes
There were outlying points and noise which caused inaccuracies in
the data
Use a different sensor configuration that reduces noise and provides greater
accuracy
PREVIOUS FLIGHT DATA
Radiation Intensity with altitude as taken by Team Cosmic, 2009-2010
OBJECTIVES
Science Objectives Measure the intensity of ionizing cosmic radiation as
flux Technical Objectives
Design and build a system that can: Withstand atmospheric conditions up to 100,000
feet Count the number of radiation hits on separate
sensors Measure the energy of radiation hits over time on
separate sensors Monitor temperature and pressure to determine
that they are in the operational range of the sensors
Record collected data and output for retrieval
SCIENCE BACKGROUND
Two types of Cosmic Rays Primary Secondary
Primary Rays High energy charged particles Enter the atmosphere
Secondary Rays Product of Primary interactions
*http://www.mpi-hd.mpg.de/hfm/CosmicRay/Showers.html
SCIENCE BACKGROUND
Possible Sensors Geiger Counter
Detects radiation with gaseous ionizing detector Creates charge relative to amount of radiation
Track-Etch Technique Clear plastic stacked Charged particle causes chemical bond breaking along
path Must be chemically dissolved after flight to observe
paths PMT Scintillator Combination
Scintillator releases light when charged particle passes through
Photomultiplier tube converts light to a charge
REQUIREMENTS
Science Requirements To measure flux of ionizing radiation as a
function of altitude Technical Requirements
Provide necessary power to all components that need it
Sample the number of hits over an interval, every 1000 feet
Convert the sensor’s current pulse into a voltage pulse
Store each measurement of cosmic ray
SENSORS AND ELECTRICAL
Geiger Counter Signal will be output as electrical charge Measures all radiation
Track-Etch Technique Plastic must be broken down with chemicals after
flight Paths must be measured with microscope
PMT Scintillator Combination Signal will be output as electrical Measures ionizing radiation passing through with
less interference from gamma radiation
PRINCIPLES OF OPERATION
After evaluation of possible sensors, the PMT Scintillator combination was chosen for feasibility test
Measurement of cosmic ray collisions as a function of current pulses over an interval
The two scintillators receive energy when charged particles collide with them. They then emit this energy as light, with the amount of light produced proportional to the energy of the particle
The photomultiplier tube collects this light and produces a current proportional to the amount of light it receives
SYSTEM DESIGN
SENSOR INTERFACE
CONTROL ELECTRONICS
POWER
POWER BUDGET
Consumer Consumption rate
Total Consumption
PMT 22 mA 88 mAh
PMT 22 mA 88 mAh
Balloon Sat 53 mA 212 mAh
DC to DC 50 mA 200 mAh
Total 147 mA 588 mAh
MECHANICAL DESIGN
External Structure ¾ inch thick insulating foam Hexagonal Shape 2 vertical holes 17 cm (6.7 in) apart through
opposite walls for interface to LaACES payload strings
Internal Structure Brace board will brace payload and carry
electronic components
WEIGHT BUDGET
Part: Measurement
method
Mass:
Foam Casing Estimated 130 +/- 10g
Power Supply Estimated 147 +/- 30g
BalloonSat Weighed 68.9 +/- 0.05g
Sensor and Interface
Estimated 150 +/- 30g
Total: 496 +/- 44g
*Estimates based upon the similar Team Cosmic payload
REFERENCES http://imagine.gsfc.nasa.gov/docs/science/know_l1/
cosmic_rays.htm http://www.srl.caltech.edu/personnel/dick/cos_encyc.html http://www.sciencedirect.com/science/article/pii/
S1350448701002281 http://galileo.ftecs.com/stone-diss/chap3/count-rate.html http://laspace.lsu.edu/aces/teams/2009-2010/teams/Cosmic/
LSU_3.php http://laspace.lsu.edu/aces/Teams/2010-2011/LSU/Avengers/
LSU_3.php http://laspace.lsu.edu/aces/teams/2009-2010/teams/Avengers/
LSU_1.php