Fuzzy Logic

Fuzzy logic is not hardware, but a software algorithm. Any microcontroller or microprocessor can execute a fuzzy logic program.

Fuzzy logic is a technique for solving a problem just like the Quadratic Equation is a method for solving a problem.

ok fine.. then please tell me briefly what is fuzzy logic!

Fuzzy logic - Wikipedia

From what I've learned, the main difference between Fuzzy and Boolean Logic is the fact that the latter is binary-based (means that it works with only two values: true or false; 1 or 0), whereas Fuzzy Logic works with continuously-variable values that range from true to false (meaning that there is a grayscale of logical values between True and False, like 63.849% True).

like 63.849% True = MAYBE!

if thats the way fuzzy works (variable from 1 to 0) then y we r using microcontrolller there. what role does a microcontrollers plays here in Fuzzy logic.

my next question?

u told that the values between true and false is fuzzy logic.. how u r achieving it.

i understood fuzzy logic now.

but my question is u told that 1.8m is 100% tall and 1.6 is 100% short more if a person is 1.75m then due to fuzzy logic it has been derived that he is 70% and 40% small.

now lets us consider that i would like to give some output regarding this ,as a display.

if suppose i consider 1.6 as 000000 in digital then i will consider 1.8m as 111111. similarly if i values to 000001 for 1.601m, 000010 for 1.602 as follow till end. and if i store some values as 2% tall and 98% small for 1.601m and goes on. i can do the program using if then logic in microcontroller

if i can i do a program in microcontroller as below. then wats the use of fuzzy logic.

It is a complicate way to do it!

You define the membership functions, the most commons are trapezoidal and triangular shapes. Looking the trapezoidal one, as shown in the figure posted before, you need only 4 values: x0 (-> y=0%), x1 (->y=100%), x2 (->y=100%), x3 (->y=0%). Then, if x is between x1 and x2 the output is only one and is 100%; instead, if x is between x0 and x1 or between x2 and x3, the program calls a sub-routine that perform a linear interpolation... in these cases there is the possibility that x is member also of a second set (is the case of the previous example of 1.75m tall that is member both Tall set and Small set). Note that, in theory, if a element is 100% member of a set it can't be member of other sets... it would be a logic absurd.

But what do you need? If you need to do a fuzzy control, that's only the first part of the control, then you have the "rules table" that ties the input with the output and the "defuzzyfication" that produce crisp value to govern the physical system.

Bob Pease wrote about fuzzy logic in his column, Pease Porridge, a few years ago. He was looking at it from the view point of an analog designer.

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