Thread: Gyro Compass
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Unread 16-01-2008, 11:04
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Re: Gyro Compass

97 is trying something similar, though we are going for the DIY approach of matching the kit gyro and a cheap digital compass to get the heading. The problem, if I understand it correctly, is: Compass is unreliable instantaneously because of noise, but good for long-term averaging. Gyro is good for short duration, but long-term it will drift away. So, there is a clever and simple to program filter that will combine the best of both into a clean heading signal.

http://www.chiefdelphi.com/media/papers/2010

You will have to use your imagination to take it from the vertical case, with an accelerometer measuring gravity, to the horizontal case, with a compass measuring heading, but I think it works. Here is a high-level diagram of what we're thinking about:

http://web.mit.edu/first/www/semiOLcontrol.pdf

Some off-board processing, but you could probably do it all on the IFI RC too. There are also other problems like magnetic interference and tilt errors, but maybe these can just be thrown into an offset factor?
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Last edited by ZZII 527 : 16-01-2008 at 11:08.