hey stefan, here is some info about PID
PID Arduino Library: Arduino Playground - PIDLibrary
WIKIPID: PID controller - Wikipedia
As I understand it, PID is a mechanism or a system that gets two values, compares them and calculates an error. That error is the distance between one value and the other. In our case, is the distance between fader position an desired fader position. This system tries to reduce that error in different waysbeing 'tuned' with 4 variables.
Reducing that error would mean for us, taking the fader to the desired position or taking desired position to the fader. As desires can't be handled by Arduino yet, the first option is the one we care about.
thats what I can hardly understand about PID, I recommend you to read Arduino's site for real information.
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