High Altitude Adventures

Transcript

1. High Altitude
   Adventures
   @jasonmadigan
   http://jasonmadigan.com
   Monday 19 August 13
   

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2. Background
   • Software Engineering type
   • Day Job
   • FeedHenry
   • Spare Time
   • Hacking (github.com/jasonmadigan)
   • iOS Apps
   • Irish Weather
   • Matchy
   • Bit of a Space nerd
   Monday 19 August 13
   

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3. Browsing Reddit One Day...
   “How hard could it
   be?”
   Monday 19 August 13
   

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4. The Plan (1)
   Lifting Gas - Hydrogen €76 + Rental
   A cheap Android smartphone
   Parachute
   Weather Balloon
   Monday 19 August 13
   

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5. The Plan (1)
   A cheap Android smartphone
   Parachute
   Weather Balloon
   Monday 19 August 13
   

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6. The Plan (2)
   Lifting Gas - Helium €170 + Rental
   Arduino + GPS + Siemens TC35 + NTX2
   Parachute
   Weather Balloon
   Monday 19 August 13
   

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7. So, what goes where?
   Balloon
   1000g Hwoyee
   48” Spherachute
   8ltr Polystyrene Box
   Monday 19 August 13
   

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8. So, what goes where?
   Balloon
   1000g Hwoyee
   48” Spherachute
   8ltr Polystyrene Box
   Monday 19 August 13
   

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9. What’s in the box?
   Arduino Mega
   Siemens TC35
   NTX2
   MTK3339
   Veho Muvi HD
   (Not Pictured!)
   Monday 19 August 13
   

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10. Payload Details
    Monday 19 August 13
    

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11. Arduino Mega
    • 4 Hardware Serial Ports
    • Software Serial ports introduce
    problems!
    • Processes GPS data from the
    MTK3339
    • Processes incoming AT commands
    read from the GSM TC35 modem
    for sending/receiving SMS
    • Controls telemetry transmission via
    RTTY sent via NTX2
    Monday 19 August 13
    

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12. MTK3339
    • Low power (20mW)
    • On-board data logging
    • Works above 18km
    • COCOM limits
    • 1900km/h && > 18000m - turn off
    • No intercontinental ballistic missiles,
    please
    • Actually worked up to 3.7km. Once.
    Monday 19 August 13
    

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13. Radiometrix NTX2
    • Low power transmitter UHF
    (10mW)
    • Free/unlicensed to use at low
    power in the UK & Ireland*
    • UKHAS use these since
    they’re easy to use
    • Used to transmit RTTY
    (Radioteletype) telemetry
    periodically
    * Table 5 - http://www.comreg.ie/_fileupload/publications/odtr0062r.pdf
    Monday 19 August 13
    

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14. Xexun TK102
    • Redundancy!
    • Cheap GPS Tracker with GSM (€30)
    • Terrible
    • Doesn’t work when it’s upside
    down
    • Randomly stops responding
    • Has failed to work on two HAB
    missions
    • I should probably throw it out.
    Remind me to throw it out.
    Monday 19 August 13
    

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15. Veho Muvi HD
    • Full HD video capture (1080p)
    • Wide angle lens
    • Rugged, similar to a Go Pro, and a
    bit cheaper (€130)
    Monday 19 August 13
    

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16. Siemens TC35
    • GSM module with a
    serial (RS232) interface
    • Works with an Arduino
    • Low(ish) power 120mW
    while idle, can spike to
    ~700mW when sending/
    receiving SMS
    Monday 19 August 13
    

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17. How it all works
    • Redundant communications system
    • GSM (via TC35)
    • SMS processing - I can call or text “where”,
    and it will text me back its location
    • UHF (via NTX2)
    • Transmits periodic RTTY for decoding on the
    ground (dl-fldigi)
    • Cheap GPS tracker
    Monday 19 August 13
    

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18. Bugs!
    • There were/are many
    • My favourite - Arduino serial interupts
    • Originally using an Uno
    • 1 hardware serial port (I needed 2)
    • Software serial ports
    • I have data, I interrupt
    • Oh you were transmitting? Sorry about
    that.
    Monday 19 August 13
    

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19. Launching!
    • Legals
    • IAA - “No”
    • CAA - “Sure”
    • Picked a remote site
    with little tree cover
    an a wide-open space
    Monday 19 August 13
    

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20. Launch Day
    • Oh crap the antenna broke
    • Oh crap the voltage sensor
    snapped off
    • Oh crap we forgot to put in
    the video camera
    • Oh crap I forgot to close
    the Helium valve before
    disconnecting the regulator
    Monday 19 August 13
    

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21. Launched!
    Monday 19 August 13
    

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22. The Chase
    Monday 19 August 13
    

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23. Oops
    • Checked the predictor, started heading
    north towards Coleraine
    • “Odd, it’s altitude seems to be stuck at
    3.7km”
    • GPS never regained a lock until it landed
    • We could hear the Payload via UHF Radio
    for the whole chase
    Monday 19 August 13
    

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24. Silence
    • Shortly after regaining GSM coverage, the
    Radio went silent.
    • TC35 & GPS Tracker still working, so
    frantically called them
    • Eventually the main tracker told us its
    location
    Monday 19 August 13
    

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25. Recovery
    Monday 19 August 13
    

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26. Some Videos
    Monday 19 August 13
    

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27. Thanks!
    Monday 19 August 13
    

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