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Unread 12-03-2008, 01:45
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Kevin Watson Kevin Watson is offline
La Caņada High School
FRC #2429
Team Role: Mentor
 
Join Date: Jan 2002
Rookie Year: 2001
Location: La Caņada, California
Posts: 1,335
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Re: Gyro Repeatability, Expected Drift ?

Quote:
Originally Posted by eugenebrooks View Post
Kevin,

You are indeed missing something. By carefully averaging
the no rotation signal, you can obtain accuracy (on average)
that is better than the ADC quantization. This improved
accuracy shows up in the resulting time integral of the gyro.

I would happily share our gyro code with you if you would
like to explore it, use it, or make some version of it generally
available. I have learned a lot about PIC interrupts studying
your code, perhaps you have one small thing to learn by
studying mine. The code, however, also uses methods to
avoid race conditions that I remember, quite well, you don't
like.

Eugene
I certainly understand how some noise components can help improve resolution, but I just don't see how integrating gyro noise when the 'bot is known to be still can help. Yes, I realize a deadband would cause problems in applications where precise low angular rate measurements need to be taken, but that doesn't apply to many FRC 'bots.

Can you point me toward a paper or anything else that can help me understand your point? And yes, please send me any code you have that I can work with. I think we have a rate table at work and it might be fun to see if I can get some freebie time on it to take some data.

-Kevin
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Kevin Watson
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