  Today manufacturers are using fuzzy logic in everything from cameras to
industrial process control. Fuzzy logic controllers are easier to design and so
are cheaper to produce. Fuzzy logic captures the impreciseness inherent in most
input data. Electromechanical controllers respond better to imprecise input if
their behavior was modeled on spontaneous human reasoning. In a conventional
PID controller, what is modeled is the system or process being controlled,
whereas in the Fuzzy logic controller, the focus is the human operator
behavior. In the first case, the system is modeled analytically by a set of
differential equations and their solutions tells the PID controllers how to
adjust the system's control parameters for each type of behavior required 3. In
the Fuzzy controller these adjustments are handled by a Fuzzy rule based expert
system. A logical model of the thinking process a person might go through in
the course of manipulating the system. This shift in focus from process to
person involved changes the entire approach to automatic control problems.
