C - code for fuzzy logic controller

[Venkatmavuru]

Hai, This is Venkat.I am a PG student in Mechanical engineering.I am doing my project on Automatic transmission of an automobile by using an Electronic controller. The controller have to select the particular gear according to the requirement,thats what does automatic transmission here mean. The controller selects the gear to be engaged depending upon the input variables ( of working condition of the vehicle ) like accelerator position,engine load etc. So the fuzzy controller takes all the input variables, processes them and then gives an output for the corresponding gear to be engaged.This is the logic how the controller works. I am not very good in Programming.So,would somebody pls help me in getting the code for this application,may be in C or C++,preferably in C. Hope u would help me in making my task simpler, Waiting for ur reply, venkat

[Ingo]

Hi Venkat,

Venkatmavuru wrote:

I am not very good in Programming.So,would somebody pls help me in getting the code for this application,may be in C or C++,preferably in C.

First this is a C# board. In this board all topics should relate to C#.

Venkatmavuru wrote:

The controller selects the gear to be engaged depending upon the input variables ( of working condition of the vehicle ) like accelerator position,engine load etc.

You have requirements and corresponding to the input values the gear will be choosen? Didn't sound like fuzzy logic. It seems to have fix states, a matrix with requirements. What is the fuzzy logic part? You should tell us a little bit more about it. Fuzzy Logic is non-deterministic.

Venkatmavuru wrote:

I am not very good in Programming.So,would somebody pls help me in getting the code for this application

Hey you should try, because you have to learn it, when you need it for your studies. So we can help you if you got stucked but I think no one here has the time to programm the work for somebody else he don't know. If you have a question you can pose it and someone here will help you. Greetings, Ingo ------------------------------ A bug in a Microsoft Product? No! It's not a bug it's an undocumented feature!

[Curtis Schlak]

I wrote a Java-based fuzzy controller that you can find at FuzzyGKS[^]. It should be relatively simple to translate it to C as the only class from the Java libraries that I use is ArrayList, I think. If that doesn't work, you may want to look around AI Depot[^] for some tips. "we must lose precision to make significant statements about complex systems." -deKorvin on uncertainty

[Curtis Schlak]

Ingo, I would like to ask a question of you, please. You state the following:

ihoecken wrote:

Fuzzy Logic is non-deterministic.

Now, perhaps I don't understand what you have attempted to say with that statement; however, as I understand non-determinism[^] and fuzzy logic (based on fuzzy set theory by Zadeh), fuzzy logic is not non-deterministic. I am a mathematician who has spent some time with these concepts. Could you please explain to me your point? Sincerely, Curtis. "we must lose precision to make significant statements about complex systems." -deKorvin on uncertainty

[Ingo]

Curtis S. wrote:

Now, perhaps I don't understand what you have attempted to say with that statement; however, as I understand non-determinism[^] and fuzzy logic (based on fuzzy set theory by Zadeh), fuzzy logic is not non-deterministic. I am a mathematician who has spent some time with these concepts. Could you please explain to me your point?

May be I'm wrong, but all Fuzzy-Logic algorithms I know are randomized. Take a look at measurement of polygons. A "coin" is dropped to an rectangular area. If it falls on the polygon it's counted. Afterwards you can calculate the size dividing the counted coints by all coins thrown. Knowing the size of the rectangular, you can calculate the size of the polygon. This is a very simple fuzzy logic algorithm, but all others I know (for picture stabilization for cameras) are working in the same way. There is always a probabilistic algorithm in the background and so it's non-deterministic. The definition of fuzzy logic has nothing to do with probabilistic working (it's about multistate bits), I know, but I don't know algorithms which uses multistate bits without probabilistics. But may be you can be explain, why it your algorithm is fuzzy logic. Talking about this part would definitiv help me. Greeting, Ingo ------------------------------ PROST Roleplaying Game

[PredictorX]

ihoecken wrote:

May be I'm wrong, but all Fuzzy-Logic algorithms I know are randomized.

No, this is incorrect. The "fuzzy" in fuzzy logic refers to graded truth values, not randomness or chance. This is an important point.

ihoecken wrote:

Take a look at measurement of polygons. A "coin" is dropped to an rectangular area. If it falls on the polygon it's counted. Afterwards you can calculate the size dividing the counted coints by all coins thrown. Knowing the size of the rectangular, you can calculate the size of the polygon. This is a very simple fuzzy logic algorithm ...

No, this is called a "Monte Carlo" algorithm, and is not fuzzy at all.

ihoecken wrote:

This is a very simple fuzzy logic algorithm, but all others I know (for picture stabilization for cameras) are working in the same way. There is always a probabilistic algorithm in the background and so it's non-deterministic. The definition of fuzzy logic has nothing to do with probabilistic working (it's about multistate bits), I know, but I don't know algorithms which uses multistate bits without probabilistics.

Although systems which employ fuzzy logic might employ randomness somewhere, the "fuzziness" of fuzzy logic is not probabilistic. I refer interested parties to: Usenet Fuzzy Logic and Fuzzy Expert Systems FAQ The Fuzzy Systems Handbook by Earl Cox (ISBN-13: 978-0121942700) Fuzzy Sets and Fuzzy Logic by George J. Klir and Bo Yuan (ISBN-13: 978-0131011717)