Fuzzy logic control using ladder logic


Thread Starter

Roberto Feliciano

I´m a Brazilian electrical engineering student. I´ve read some articles about artificial inteligence and I´m so excited to implement fuzzy logic controllers in PLCs (Modicon or AB). Can you help me to find some material on web ? Or maybe we just could exchange some infos about it.

Roberto Feliciano Dias Filho
I've thought about doing the same thing, but implementing the fuzzy sets and rules in ladder could take quite a large number of compute blocks. Instead, I envisioned implementing the final control surface as a multi-dimensioned lookup table (i.e., discretize the fuzzy controller's output and store it in a memory file). If I understand correctly, that is how fuzzy is actually implemented in appliances,
cameras, and the like. Unfortunately, I have not had a need to do this on a project so I have not been able to find the time to try it.

Good Luck,

Chip Hinde
Los Alamos National Laboratory
Schneider's Concept software for Modicon PLC's has some built-in function blocks for Fuzzy logic. I've never used them, I just remember going through the manual and seeing that they were there.

Best of luck.
Don Zunti, P. Eng.
Delco Automation Canada

Waddell, Reginald E

I have implemented a fuzzy logic controller using a Honeywell TDC3000 DCS system. Maybe I can give you some ideas with the PLC implementation.

Reginald Waddell
Control Engineer
[email protected]

Juha Katajisto

Hi, I have implemented sugenos FIS with my Siemens S- 300 logic controller. For a smal system (only few Input and Output) It won't need so much for codeign. If you'r interestid you can contact on me and I can send you some ideas or even sample code I wrote Step7.

Good luck

Juha Katajisto
Häme Polytechnic, Insructer

[email protected]