Original URL: http://www.theregister.co.uk/2012/07/17/pi_ascent/
Raspberry Pi used as flight computer aboard black-sky balloon
PENGUINs in SPAAAACE!
Posted in SPB, 17th July 2012 09:43 GMT
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Pics A Brit amateur balloonist has pulled off two major achievements: getting his hands on [1] a wallet-sized Raspberry Pi computer and then sending it heavenwards to 39,994m (131,200ft).
Over the weekend, Dave Akerman's PIE1 payload was carried aloft into the stratosphere under a latex meteorological balloon, sending back live webcam images - something which Dave notes "hasn't been done very often".
Dave (pictured) explained [2]:
In early May I received my first Raspberry Pi computer, and having flown several high-altitude balloons before I thought about using one as a flight computer. In almost all of my previous flights I used Arduino Mini Pro boards, and these are ideal – tiny, weigh almost nothing, simple and need very little power.I looked at the Pi and saw none of these desirable features! What I did see though was a USB port offering quick, easy and inexpensive access to a webcam, meaning that for the first time I could have live images (Slow Scan Digital Video) sent down by my payload.
Concerned that the low-heat dissipation at altitude might cause the cheap-as-chips ARM-powered Pi to overheat, Dave added some heatsinks to his board...
...then rigged a "Radiometrix NTX2 radio transmitter to send the telemetry and images down to the ground, and connected that to a simple GPS receiver":
The launch was from Dave's home village of Brightwalton, in Berkshire. Dave told El Reg he was using a 1200g Hwoyee balloon, and expected a burst altitude of around 34,000m (111,500ft).
In the event, it soared to an unexpected peak altitude of 39,994m, not far short of Dave's "Buzznick" balloon that reached 40,575m [3] in December. He says he's since beaten that height twice: his BUZZ6 flight in May hit 43,639m (143,172 feet).
The webcam proved a great success. Here's an image transmitted from altitude before the Linux-powered Pi payload finally came down in a field north of Oxford:
Dave's orb was filled with hydrogen, as indeed were all of the mighty globes currently occupying the top six positions in the UK altitude record chart [4].
Doubtless this will renew efforts by inflammable gas experts to convince us to use hydrogen for our Low Orbit Helium Assisted Navigator (LOHAN [5]) mission, but we're sticking with cigarette-friendly helium, thanks very much. ®
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All snaps are © Dave Akerman, who we thank for permission to reproduce them here.