Since fuzzy controllers are nonlinear, it is more difficult to set the controller gains compared to proportional-integral-derivative (PID) controllers. This research paper proposes
a design procedure and a tuning procedure that carries tuning rules from the PID domain
over to fuzzy single-loop controllers. The idea is to start with a tuned, conventional PID
controller, replace it with an equivalent linear fuzzy controller, make the fuzzy controller
nonlinear, and eventually fine-tune the nonlinear fuzzy controller. This is relevant whenever a PID controller is possible or already implemented.