Quote:
Originally Posted by Ether
How closely did the actual measured speed match the speed you were commanding?
I ask this because other teams have reported that they could control speed, but the actual speed did not match the commanded speed.
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In all cases my steady state error was +/- 200 rpm. Now I say this sparingly. The only indication I had of actual speed was the readout from the BDC-COM interface, which was fluctuating within this range.
However, I would argue that most of that fluctuation is due to the lack of smoothing the input rate of the encoder and causing the PID loop to iterate to reduce the error. If there were no noise in the feedback signal, fluctuations in the output can be fixed by reducing the P term of a PI controller, however this will reduce your rise time.