High Altitude Adventures

Transcript

1. High Altitude Adventures @jasonmadigan http://jasonmadigan.com Monday 19 August 13
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
3. Browsing Reddit One Day... “How hard could it be?” Monday 19 August 13
4. The Plan (1) Lifting Gas - Hydrogen €76 + Rental A cheap Android smartphone Parachute Weather Balloon Monday 19 August 13
5. The Plan (1) A cheap Android smartphone Parachute Weather Balloon Monday 19 August 13
6. The Plan (2) Lifting Gas - Helium €170 + Rental Arduino + GPS + Siemens TC35 + NTX2 Parachute Weather Balloon Monday 19 August 13
7. So, what goes where? Balloon 1000g Hwoyee 48” Spherachute 8ltr Polystyrene Box Monday 19 August 13
8. So, what goes where? Balloon 1000g Hwoyee 48” Spherachute 8ltr Polystyrene Box Monday 19 August 13
9. What’s in the box? Arduino Mega Siemens TC35 NTX2 MTK3339 Veho Muvi HD (Not Pictured!) Monday 19 August 13
10. Payload Details Monday 19 August 13
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
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
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
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
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
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
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
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
19. Launching! • Legals • IAA - “No” • CAA - “Sure” • Picked a remote site with little tree cover an a wide-open space Monday 19 August 13
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
21. Launched! Monday 19 August 13
22. The Chase Monday 19 August 13
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
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
25. Recovery Monday 19 August 13
26. Some Videos Monday 19 August 13
27. Thanks! Monday 19 August 13