Encoder for a fly wheel

[z_beeblebrox]

Originally Posted by Ether

You didn't mention the RPM you are trying to control. At 48 counts per rev at 5000 RPM, you're going to get roughly 150 RPM jitter with GetPeriod() if you leave the FPGA sample averaging at the default value of 1. If you set the samples to 48, you'll get the same clean signal as a one-per-rev sensor at that speed, namely 3 RPM.

If you use Get() to get counts instead of period, and your control loop is running at 10ms, you're going to see about 125 RPM jitter at 5000 RPM. If you try to filter that in software, there may be too much phase lag to get clean control with bang-bang.

Probably dumb questions, but how does one adjust the FPGA sample averaging count? Will this give fast enough updates to use with a bang-bang controller?