Introduction to Fuzzy Logic

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Introduction to Fuzzy Logic
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Fuzzy Logic

• Method of reasoning that represents human
  reasoning allowing for approximate values and
  inferences.
• Uses language that is deliberately imprecise.
• Provides approximate but acceptable solutions.
• Fuzzy logic is a superset of conventional
  (Boolean) logic that has been extended to handle
  the concept of partial truth- truth values
  between "completely true" and "completely false".
  
• As the complexity of a system increases, it
  becomes more difficult and eventually impossible
  to make a precise statement about its behavior,
  eventually arriving at a point of complexity
  where the fuzzy logic method born in humans is
  the only way to get at the problem.
• It should be noted there is controversy and
  criticism regarding fuzzy logic.

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Fuzzy Logic Method

• Measured, non-fuzzy data is the primary input for
  the fuzzy logic method.  
• Examples   temperature measured by a temperature
  transducer, motor speed, economic data, financial
  markets data, etc.

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Fuzzy Logic Sets

• A fuzzy set is a group of anything that cannot be
  precisely defined.  
• The fuzzy set of "old houses."
• How old is an old house?  

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Fuzzy Logic

• Fuzzy logic is used in system control and
  analysis design, because it shortens the time for
  engineering development and sometimes, in the
  case of highly complex systems, is the only way
  to solve the problem.

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Fuzzy Logic Examples

• Self-focusing cameras
• Washing machines that adjust themselves according
  to how dirty the clothes are
• Automobile engine controls
• Anti-lock braking systems
• Subway control systems
• Computer programs trading successfully in the
  financial markets.