Fuzzy Logic

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Fuzzy Logic is a mathmatical approach to solving a problem rather than a Boolean or Binary (True/False) approach. This approach to solving problems is similar to the approach we use. It was first thought up by Dr. Lofti Zadeh in 1964 when thinking about alternatives to the Current Method of Air Conditioning

Brief History

Theory about Fuzzy Logic can be traced back to ancient times. Before Aristotle came up with the theory of binary logic, Buddha suggested that everything contained some of its opposite. Meaning good contained some evil, dry contained some wetness, hot contained some cold, etc. This is a theory behind fuzzy logic; nothing is completely true or completely false.

In 1964 Dr. Lofti Zadeh was attempting to find a new and more efficent method of programming Air Conditioning units over the then used method. He proposed that it would be simpler to tell the conditioner to work harder when it got warmer and to work less when it was cooler then to set a series of rules for each temperature.

In the mid 1980s in Japan, fuzzy logic was used to control trains. Trains were programmed to apply breaks at upon reachin carkers set at even distances away from the station. However these trains would apply breaks the same going downhill as they would going uphill. This would result in the trains coming to a jerky stop in certain situations. However by harnessing fuzzy logic engineers at Hitachi were able to make the breaking process much smoother. This and other uses of fuxxy logic to increase the performance of trians in Japan fueled for a boom in the use of fuzzy logic overseas.

How It Works

If you had a group of 50 individuals and you wanted to classify them as old or young you can see how the two approaches differ. In the Boolean approach anyone over a defined age, lets say 45,would be classified as old and everyone else would be young. So someone with the age 44.9 would be classified as young but at 45.0 they would become old.

Fuzzy Logic works on a sloping line. So it could say that everyone up to 40 would be considered absolutely young but from ages to 40 to 50 they would increasingly be considered more old. This comes out to define people as somewhat old or somewhat young in those years in which thier age/oldness is fuzzy.

Fuzzy Logic is used to determine a conclusion based on vague and noisey information that would be indeterminable by traditional problem solving methods. It is used to mimic human control of an application. By using a descriptive yet impercise language it deals with the data much the way a human controller would. Though it is inpercise it is still forgiving of data input and rarely needs much fine tuning.

Examples of Fuzzy Logic used for movie A.I. includes Massive Software Massive Software which was used in the Lord of the Rings Movies as well as the Chronicles of Narnia