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Unread 29-02-2012, 00:13
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Re: Consistent encoder rate

Quote:
Originally Posted by jaysun View Post
I should clarify my last post and note that my video was not based off my actual data. I generated the "measurement" (green line) by adding a random number to the rate I set - in reality the "amplitude" of the noise is about half of that. The red line is the IIR, and the blue line is the moving average.

With the optical encoder I use the DSC.

Yes, I made sure the encoder wheels were not scratched - I scratched a lot of them when we first started using them last year. We did twist the encoder wires with a hand drill to make the wiring look good - maybe that's a problem?

Thanks for the ideas. I'll try to use a new, different encoder cable and separate the power and data wires and see if the rate I get is any less noisy.
Twisting the wires like that is some serious abuse; you're placing a lot of tension on a solid length of copper. Wire may flex, but spinning it is asking for trouble. If anything, braid the wires.

To clarify, I don't mean separating the power and data lines coming from the encoder; I meant separating all 4 encoder lines (+5, A, B, GND) from the power lines going to the motor. Ether, could you comment on how recognizable this effect would be?
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