fuzzy in PLC

Thread Starter

h.d

Joined Oct 22, 2007
150
hi all,
i want to ask about PLC and kinds of PLC's which have fuzzy logic capabilities , and if you can feed me with some applications.
 

Papabravo

Joined Feb 24, 2006
14,460
I worked at Allen-Bradley for several years, and as far as I know, none of the PLC guys would EVER consider using fuzzy logic on an industrial process where lives are at stake. On top of that they would never consider trying to explain fuzzy logic to the plant electricians who understand and revere ladder logic. Industrial control moves at a glacial pace compared to other segemnts of industry.

Come to think of it I'm not sure I know of any practical applications of fuzzy logic. I think it was one of those flash-in-the-pan kind of things. I could be wrong however, so let us know what you find out.
 

Thread Starter

h.d

Joined Oct 22, 2007
150
I worked at Allen-Bradley for several years, and as far as I know, none of the PLC guys would EVER consider using fuzzy logic on an industrial process where lives are at stake. On top of that they would never consider trying to explain fuzzy logic to the plant electricians who understand and revere ladder logic. Industrial control moves at a glacial pace compared to other segemnts of industry.

Come to think of it I'm not sure I know of any practical applications of fuzzy logic. I think it was one of those flash-in-the-pan kind of things. I could be wrong however, so let us know what you find out.
ok first , thanks for your replay,
about fuzzy functions ,some of siemens PLC's have that function but up to know i font know which it .
i will still search,thats is a PLC lab. project from doctor so sure thier are PLC's
with fuzzy logic control.
 

thingmaker3

Joined May 16, 2005
5,084
Looks like Allen-Bradley is even making them now. For use in mills, no less.

From what I can tell, the "fuzzy" part of "fuzzy logic" is all in the sales literature. The part about "can only be described with words" is actually done with calculus. ("Derivative" is a word, aint' it?)
 

beenthere

Joined Apr 20, 2004
15,819
I kinda like the thought of fuzzy logic in PLC's. The greater part of the worker is out of the beam path, so energize the laser. There is only 1 of 10 fingers in the path of the cutter, start planing. And so on...
 

RiJoRI

Joined Aug 15, 2007
536
am dont understand well what you are say??
Those, h.d., are humorous examples of why fuzzy logic might not be a good idea in an industrial environment.

I know National Semiconductor had fuzzy logic software for their COP-8 chip. It ran on a PC, and would fuzzify and de-fuzzify and produce output for their chip. Unfortunately, they no longer make the chip, and I guess they do not have the Fuzzy-ware.

Maybe it was Bob Pease of NS that killed it off: http://www.national.com/rap/Story/fuzzylogic2.html

--Rich
 
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