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Team 7,  Final Presentation December 1, 2011

Team 7,  Final Presentation December 1, 2011. Mission Overview Send up petri dishes containing bacteria Analyze the effects of temperature, pressure, and UV radiation on the bacteria Attempt to capture bacteria in tropopause in a sterile petri dish attached to a servo. Design Overview

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Team 7,  Final Presentation December 1, 2011

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  1. Team 7, Final PresentationDecember 1, 2011

  2. Mission Overview Send up petri dishes containing bacteria Analyze the effects of temperature, pressure, and UV radiation on the bacteria Attempt to capture bacteria in tropopause in a sterile petri dish attached to a servo

  3. Design Overview • Petri dish attached to servo controlled by Arduino • 3 other petri dishes • HOBO, heater, camera Arduino Uno Function Block Diagram Parallax Standard Servo

  4. Design Changes Funnel and holes added New petri dish seal Spring added inside Size reduced

  5. Incubation of Bacteria • Flight bacteria applied to LB (Luria Bertani) agar plate using sterile swab • All dishes incubated for 5 days at 37 degrees Celsius • Dish #1: Flight bacteria exposed to nothing • Dish #2: Bacteria exposed to just UV • Dish #3: Bacteria exposed to UV, low temperature, and low pressure

  6. Dishes Before Incubation

  7. Dishes After 1 Day of Incubation

  8. Dishes After 5 Days of Incubation

  9. Control Dishes Negative Control                                             Positive Control

  10. Bacteria Capture Dish Before Incubation              Day 5                      Day 1 No Growth

  11. Analysis of Bacteria • No bacteria collected from the tropopause  • Broken seal • No bacteria growth due to dryness of agar • Bacterial growth on all three flight dishes • Colonies for all three look different • Possibly not growing just E. Coli

  12. Analysis of Bacteria • Dish 3 looked similar to the control • Dishes 1 and 2 had different color and shape  • Sterile incubation techniques were used  • Plates may still have been contaminated by bacteria in the air • The negative control had no growth • Possibly because it was not exposed to the air long enough to be contaminated • Or because it was only incubated for 1 day

  13. Predictions vs. Results • Prediction: only the dish exposed to nothing would grow bacteria • All three dishes ended up growing bacteria • Prediction: mission would successfully capture and grow bacteria from the tropopause • No bacteria grew in that dish

  14. External Temperature and Altitude Black Line: External Temperature Blue Line: Altitude Times when petri dish was open Burst Sunrise Launch Landing Burst In tropopause during ascent In tropopause during descent

  15. Internal Temperature and Altitude Interior continues to warm after landing Black Line: Internal Temperature Blue Line: Altitude Times when petri dish was open Burst Sunrise Launch Landing Near tropopause during descent Burst Near tropopause during ascent The satellite’s insulation caused interior temperatures to change after external temperatures; for instance, the coldest interior temperatures were recorded slightly after the satellite went through the tropopause. Note that the temperature dropped below the -10 degree mark due to failures in heating and insulation.

  16. Relative Humidity and Altitude Satellite lying in moist grass in humid Nebraska (61% average humidity*). Black Line: Relative Humidity Blue Line: Altitude In tropopause during ascent In tropopause during descent Burst Landing Sunrise Launch Times when petri dish was open Relative humidity roughly increased as temperature decreased. *Source: http://www.wunderground.com/history/airport/KSNY/2011/11/5/DailyHistory.html?req_city=NA&req_state=NA&req_statename=NA

  17. Pictures

  18. Flight Recap • Bacteria grew on all three flight dishes • Broken seal and no growth for collection dish • Insulation failure • Low internal temperature • Camera shut down

  19. Camera Failure No pictures taken after first half of ascent Caused by low temperature  Confirmed by cold test Structural Failures Electronics dislodged Faulty attachments Lack of planning Air Vent Failure Analysis

  20. Resealing Petri Dish Failure Petri dish landed unsealed Hard landing Dish not supported by Foam Core underneath Failure Analysis Continued

  21. Thermal Failure • Insulation failure led to internal temperature of -50 degrees • Needed foam, not thermal blanket • Results repeated in cold test • Showed problem was with insulation, not heater as in initial tests Test begins Test ends

  22. Conclusions • No bacteria were captured from the tropopause. • We cannot conclusively state whether or not the bacteria we sent up survived due to some contamination. • The dish that was exposed to UV, vacuum, and low temperature had colonies that appeared similar to E. Coli so that bacteria apparently survived.

  23. Lessons Learned: Improvements for Next Flight • Use quartz glass petri dishes for the dishes exposed to UV  • Plastic absorbs much of the UV that passes through it • Use an agar selective to E. Coli to ensure only E. Coli is growing • Find a way to prevent the agar exposed to the vacuum from drying out • Secure petri dish more securely to prevent the seal from breaking • Use foam for insulation in addition to a thermal blanket

  24. Ready to Fly Again • Payload preparation • Sterilize petri dishes • Fill dishes with agar • Put bacteria in three dishes • Payload activation • Press button to activate camera • Flip switches to activate servo and heater • Insert pin connecting servo arm to petri dish after arm has twitched to confirm activation

  25. RFP Requirement Compliance

  26. Cost and Weight Budgets Final Budget:      Total Money Spent: $225.68     Budget Remaining: $24.32 Mass:     Total Mass Used: 805 grams     Total Mass Sold: 30 grams     Mass Remaining: 15 grams

  27. Message to Next Semester Think of a mission that truly interests your team. If you care about what you might discover, you will find it much easier to stay motivated. Fight through the work; it's worth it. You will miss this class when it is all over. Make sure you put a lot of effort into the proposal and the whole project. You will need to do a lot of work to actually do well on it. DRESS UP FOR YOUR PRESENTATIONS! It took our class half the semester to figure that one out.

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