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Unread 09-05-2015, 15:25
sanddrag sanddrag is offline
On to my 16th year in FRC
FRC #0696 (Circuit Breakers)
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Re: pic: Small CIM in wheel swerve

Quote:
Originally Posted by Ether View Post
If your sample time is fast and stable enough that the encoder could never turn 180 degrees from one sample to the next, then "all ya gotta do" at each sample is assume the encoder turned through the shortest angle, and keep track of zero crossings.

I think that's essentially what our programmer did, although the libraries involved had some glitches that presented many headaches.

For those of you discussing "drift" with incremental encoders, are you referring to an accumulation of lost counts? Does this happen when the direction of steering reverses, and is this accumulation of lost counts biased toward one direction? Would the solution to have something like a hall effect sensor for zeroing, and reset the count every time you cross it?
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Teacher/Engineer/Machinist - Team 696 Circuit Breakers, 2011 - Present
Mentor/Engineer/Machinist, Team 968 RAWC, 2007-2010
Technical Mentor, Team 696 Circuit Breakers, 2005-2007
Student Mechanical Leader and Driver, Team 696 Circuit Breakers, 2002-2004
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