Ghetto-UAV
One day in 2004 i found a Medion 2.4Ghz AV-transmitter at local market
for 50¤. They were expensive back then (200-300¤) so i bought it.
That started the idea of putting it aboard a RC airplane. I bought
a small camera module and wired it and the transmitter to work
with two 9v batteries. I bought a cheap car DVD player that had
a separate DVD player and a small TFT display that could display
composite video.
I had a wing from old Mini Challenger electric glider and made a
fat fuselage from balsa wood. I decided to make a glider
to keep things simple. Maybe later i'll put the transmitter
on a powered model.
The pics
Fuselage constructed in about one evening.. Usually i make
EPP models so it was quite intresting to make a oldschool
balsa model again.
Here's the receiver setup on test piano. Image quality was
quite good, but not perfect.
I removed the useless plastic covers from the transmitter and
fitted it inside the fuselage.
Front side of the fuselage.
Altough the fuselage was made fat on purpose it was hard to
stuff all the electrics inside. There are 2 9v batteries
to get 18v for transmitter. I ditn't want to solder leads
directly on the transmitters board so i used RCA connectors. Maybe
i should have done it as the plugs take much space after all.
Middle section of the fuselage. Here's the transmitter board stripped
from its plastic covering. The camera has also microphone so
i have connected composite video and other audio channel
to transmitter.
Rear section of the fuselage. Here's the usual servo stuff, RC receiver,
and transmitter antenna (flat plate barely visible). RC battery
was in the nose section.
Camera mounted on the front of the glider. It's small
but quite heavy because of the metal casing. I could
have removed the casing but i decided to keep it on to
prevent damage to camera on crashes. Small hole houses
the microphone.
Off to the field i went.. Here's the "before shot" because
i ditn't have a clue how the glider would fly with heavy
transmitter stuff inside. Camera is mounted with ghetto
style rubber band.
Closer look at the camera.
Here's the receiver setup i used on the field. It's powered
with car battery. Notice the directional antenna on
receiver. I launched the glider with a bungee and got it to
a quite good height. It glided well and the flights lasted for
a couple of minutes.
What happened then??
Sorry, no more pictures. I was alone at the field so i had
to concentrate on piloting. Flights went fine - the glider
and transmitter both remained undamaged. It transmitted image and sound
to the display and everything worked fine. It wasn't possible to
fly the glider with the transmitted image because the transmitter
antenna is quite directional and the image went poor when the
glider was at certain angle to the receiver. I'm not sure
about image quality as it was limited by TFT display's poor
resolution (less than 640*480) and bright outdoor light.
Transmitter range was not an issue - the image was good
at distance except when the glider was in bad angle.
I didn't have a video camera or anything else to capture the
video, sorry. Next time i'll try to lend a DV camera from
someone.
Next time
Use less directional antenna and capture the image to a
DV camera. Have someone with me to take photos and
video. I'll update this page when that happens.
Until then, see more ghetto engineering at
Afrotech's.
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