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Unread 23-01-2017, 17:18
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Making the 1's and 0's
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Re: Minimum Flywheel Encoder CPR

Assuming you're measuring off of the flywheel:

A single cycle per revolution on a slow flywheel would still get you at least 2000/60 = 33 cycles per second. This might be a bit low for a tight control loop, but you could definitely work with it.

I say this is ok because it means you get information on each edge of the encoder, so 66 times per second. This means the fastest it makes sense to fully evaluate your control algorithm more than ever 1/66th of a second (about 15ms or so, which is on par with most algorithms).

Now, in general, it's better to get a handful of samples and average them, but you could still get by without it in many cases....

So, basically any encoder. The worse limit is having a very high CPR, and generating frequencies beyond the sampling limits of the controller. Still, the RIO samples at 40MHz, so this would still be hard to violate.

Last edited by gerthworm : 23-01-2017 at 17:22.
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