# Fuzzy logic control vs PID [Resume]?

Tags:
1. Mar 28, 2016

### barzi2001

I have found this topic but I am not allowed to answer.

I have the same concern that the fuzzy is basically similar to a proportional control.

http://www.ece.uidaho.edu/ee/classes/ECE573F05/PID%20vs%20Fuzzy%20Control.pdf [Broken]

but it does not work any longer, and I cannot find.

Can someone explain me in which way the fuzzy differs from the proportional control, or provide some link?
Many thanks.

Last edited by a moderator: May 7, 2017
2. Mar 30, 2016

### donpacino

PID control:
takes 3 inputs (the value of the input, the derivative of the input, and the integral of the input)
Multiplies each one by a scalar
sums them
it design assums linearity

fuzzy logic control
lets make our fuzzy logic controller use three inputs (the value of the input, the derivative of the input, and the integral of the input)

each input has a corresponding input graph. Use the output of those membership functions on an output graph to determine your output.

You can make the membership functions as course or fine as you want. You can make it non linear, or linear (over a range)
linearity does not matter in any way.

fun fact
you can actually make a fuzzy logic control that is IDENTICAL to a PID controller.

Fuzzy logic is basically a way to use words and simple graphs to describe and create a cost function. You can make non-linear functions that would be extremely complicated to create via traditional methods.

3. Mar 30, 2016