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Unread 08-03-2013, 10:48
JefferMC JefferMC is offline
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Re: Encoder getRate question

On encoders for shooting wheels, you may wish to watch out for the maximum RPM the encoder can handle. There are both electrical and physical issues there.

You can also approach the granularity of the VxWorks timer, which I believe has a resolution of 6 us. Since GetRate() gives you the inverse of the time between the last two ticks, with a resolution of about 6 us, this caused us some issues with oscillation between two substantially different returned values for RPS. Using the FPGA with the ring buffer may help with this, but we opted for the x1 resolution.
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