Andrew Huff, student at The Grammar School Leeds, has shown how the Raspberry Pi cut down computer can be used for an all in one offline tracker, camera, and GSM locator for high altitude balloon flights.
Andrew picks up the story in his own words.
Six months ago, after being fooled by the “free computers” sign on my
computing teachers door and receiving a credit card sized Raspberry Pi
computer, I then had to prove myself to be “worthy” of receiving this
£20 Linux PC. So, no sooner said than done I decided to take on the
daddy of all Pi projects – to send it up 90 thousand feet into near space.
I’ve seen the photos countless times before, a cloud covered sphere with
a thin blue haze, glowing against the backdrop of space and yet I still
wanted to replicate it myself to see if this weird, soundless place
really did exist for someone like me, who doesn’t usually receive NASA
funding. Better still, to be able to reach this place with something
which I made and understand myself, captivated me and so from this point
on, I set out to create and program a Raspberry Pi which would be
capable of recording flight data, taking photos and most importantly
being able to send me its position afterwards so that I could collect it.
David Ackerman, the first person to use a Pi for high altitude
ballooning and the many other micro-controllers which preceded mine, all
used armature radio to track down and receive data from the payload. The
benefits of using radio to track the Pi would be that I would be able to
follow it for the entire period that it is in the air and the coverage
is allot better than the patchy GSM network which I settled upon using.
However, as I found out, understanding and then using radio to track the
Pi is allot more complex than just sending an SMS though a mobile dongle
so I soon settled on using that instead.
The next problem came from having to interface with the GPS module.
Before I started this project, all my programming experience was writing
small space-invaders games in BBC BASIC and so having to send binary
and hex commands to an external device was a real shock, which took me a
few days and allot of headaches to figure out. The good news though, is
that after I finally cracked it, I had a much deeper understanding of
how and why the technology worked which was a far cry from the “copy and
paste someone else’s code” approach which I honestly thought this
project would be at the beginning.
As the project grew in complexity, so did my ambitions and so I decided
to add a thermometer to the Pi to see just how cold it gets up there
(and FYI. the pilot isn’t lying when he announces that it’s -50 outside
the aircraft). Although simple to code, the thermometer taught me
another important life skill which was soldering – my new favourite way
of joining anything! All the information on how to do this was readily
available online and it’s well worth doing since it leaves you with a
warm, glowing sense of accomplishment inside, that what you have just
fused together will never ever fall apart. (Just kidding, I’m not that
Finally, came launch day. Chris and I set up our equipment and after
filling the balloon and giving an on the fly briefing to our small crowd
of spectators, I let it loose to ascend into that mysterious world which
I first was hooked by over six months ago. I was nervous yet at the same
time proud and satisfied that something which I built was hanging there,
in Arctic temperatures and in an atmosphere one twentieth of what I was
in at that time, beeping and flashing away all on its own, suspended
above a 26km plummet to the earth. But of course, it wouldn’t stay that
way for long. After the inevitable “pop” the real action took place and
as we raced across Yorkshire and Lancashire, finally came the
“ba,da,ding” from my phone which I was praying for. We drove to the last
known location and sure enough, Chris spotted the payload in the middle
of a field between two power lines and a wood. Unfortunately, on impact
the Pi had disconnected its self from the power and so that’s why in
actual fact, we ended up using the backup tracker to pinpoint its
precise landing spot. However, none of this really mattered because in
the end I had proved to myself that I was able to get into near space
and back again using only my year and a half’s computing GCSE course and
a £20 PC.
But that’s only half of the storey, this project went allot deeper than
just computing. I had to organise CAA permits, secure landowner
permission, talk to Professors, convince the school’s marketing
department to fund me and finally be lucky enough to get in touch with
Chris who helped me an indescribable amount to shape the project into
what it has successfully become. In total, what had started off as a small computing idea, has grown into an irreplaceable learning
experience with far reaching benefits for a sixteen year old student