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Unread 21-02-2011, 16:16
jhersh jhersh is offline
National Instruments
AKA: Joe Hershberger
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Re: LabVIEW Encoder not reliably returning Rate

Quote:
Originally Posted by ayeckley View Post
Using LabVIEW, our initial application of the workaround seems to result in the "Rate" output scaling based upon the value of "DistancePerCount" (for a given angular velocity using an E4P and 2X decoding). This behavior is nonintuitive and isn't suggested by the Help File for the WPI_EncoderGet.vi even when reading between the lines.
It should and always has been scaled by the distance-per-count. Without that, the units would not be consistent between distance and rate. The idea is that if you differentiate the distance, you should get (almost) the same answer as rate.

-Joe
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