Few thoughts....

(1) For small model airplanes, you'd need to make really,
really quick corrections to pull this off, and I'm not
sure if GPS (even 3) would be precise enough for that.
But I may be wrong here.

(2) Ever heard of WAAS (Wide Area Augmentation System)?
Originally conceived & started development when SA was
still active.  Not sure what ever happened with it though.
A quick google search for 'WAAS' should net you a lot of
good info though.  Sounds like that's what you want
implement.

(3) Sounds like a full autopilot system developing here,
so stay tuned for the paranoid responses, which I
probably have to agree with more here than for cruise
control.

(4) A lot of electronics in one small plane.  First up,
figure out roughly what electronics will be needed, then
pick a model plane that can handle that extra cargo.
Now figure out the price of that puppy, and if you can
afford it.

(5) Speaking of affording it, you'll need to buy the
planes wholesale for the testing phase. :-)

Cheers,
-Neil.



-----Original Message-----
From: pic microcontroller discussion list
[mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Tan Chun Chiek
Sent: Tuesday, June 18, 2002 9:09 PM
To: PICLIST@MITVMA.MIT.EDU
Subject: [PIC]: Autopilot landing system for model aircraft


Hi,
    This idea of an autopilot landing system just popped up in my mind, and
other details came almost immediately. I thought why hasn't anyone done it
before? The runway is something like 10m X 50m. GPS is used for
longitudinal/latitudinal positioning and preferably velocity measurement,
the aircraft would have a GPS receiver onboard, and 2 other GPS receivers
would sit on the both long ends at center of the runway, it's something akin
to differential GPS to provide better accuracy. Height measurement is done
by a ultrasonic transceiver or maybe GPS, are they accurate enough? And
pitch and roll is sensed by a pizeo gyroscope.

How feasible is this concept?

Regards,
Tan CC

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.