DISCLAIMER (PLEASE READ)
If you try this yourself, you do so at your own risk. I strongly recommend
that you make a 'test pilot' out of a bunch of 1x16 Technic beams and a Lego
weight element. That's what I did to try and figure out the bridle setup for
slinging the RCX under the kite. My first test flight from the balcony launch
position was an immediate stall and plummet -- I'm not sure the RCX would have
survived if it had been attached. Similarly, once I had the RCX mounted, I did
numerous test launches at ground level before moving up to the balcony launch
point. Start small, work up, and don't blame me if you trash your RCX.
The 'hang glider' was actually a slightly modified two meter stunt kite.
The flight path was trivial -- fly straight for one second and then run a micromotor
(attached via a cam and tiller line to the bridle of the kite) for a brief interval to
shift the weight of the RCX and bank the kite into a gentle descending spiral. I chose
this flight path because: a) I wanted the RCX to do something, not just be a dumb
payload; b) as you can maybe see from the flight photos, our yard is not the ideal place
for testing this application of the RCX -- there is a big tree to the right of the
launch point, a telephone pole with cables strung to our house on the left,
and a chain-link fence around the perimeter; I wanted to avoid smashing the
RCX into any of the above if at all possible.
The program used for this job can be downloaded from the Code link. The program
beeps a countdown, waits one second, turns the micromotor on for a brief interval;
after the countdown, a separate task beeps at 0.5 second intervals so that I
can tell the flight time.
The trick is to power the RCX with an external 9V battery connected to the RCX's
AC/DC power port, and then take the six AAs out. This modification makes the RCX
significantly lighter, thus prolonging flight time and also reducing the g-shock
on 'landing'. Note that the RCXs which come with the LEGO RIS 1.5 and 2.0 do not have
an AC/DC power port -- if you don't have RCX 1.0, no one can call you a chicken
if you don't try this yourself.