Fuzziness: what am I missing?

Andy Bates (andyba@corp.webtv.net)
Mon, 6 Apr 1998 15:31:11 +0200 (MET DST)

Okay, I'm confused about Fuzzy Logic. From what I understand of it, it's
basically an easier way of generating a function curve between inputs and
outputs (when applied to logic circuits, for example). But the curve itself
is still a line, not a group of patches, so why is this any more desirable
than, say, some function that forms that line?

Let's see if I can make this clear with an example. For a sample problem,
I'll use the basic fuzzy air-conditioner problem: if hot then blast, if
warm then normal, if cool then low. So, no matter what the fuzzy rules, for
any given temperature (input), that input will be fuzzified, correlated
with a fuzzy output value, then that value will be de-fuzzified into a
specific fan speed (output). So if you drew a graph, you could match all
input values with a corresponding specific output value, forming a curve on
the graph. Therefore, how is this any different than, say, taking a normal
mathematical function and mapping the input temperature to the output fan
speed?

Help me! I'm confused here. Fuzzy Logic seems great as a concept, but I'm
having trouble figuring out how to apply it to programs, or what benefit I
gain from it. I am trying to create a simple application using fuzzy logic
as a sort of proof-of-concept, but I seem to be losing the faith as far as
the application.

Andy Bates.