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Unread 04-02-2016, 14:36
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Ether Ether is offline
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Re: Finding RPMs with encoder

Quote:
Originally Posted by Sparx030 View Post
On the shooter wheel

This may change but let's just say 3000 RPM

It will be directly connected

AndyMark RS775-5 with a Victor controller

The RIO

Also, if possible, would you be able to provide a brief generalization of what each decoding type is used for?
Not that it matters that much, but Victor SP or 888 ??

And did you consider using bang-bang instead of PID? This is the perfect application for it. And there's no tuning required.

A 250 CPR encoder spinning at 3000 RPM is easily decoded by the roboRIO at 4X or 2X or 1X. It samples for edges much faster than the cRIO did, which removes many of the considerations which came into play in the cRIO days with high-RPM high-CPR encoder use. But, there are still some things you need to know to be successful.

I will expound on that and answer the rest of your questions in a few minutes.

EDIT: Oh, and what is the period of your control loop (e.g. 20ms, 10ms, etc).



Last edited by Ether : 04-02-2016 at 14:50.
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