Hardware Implementation of Embedded Fuzzy Controllers on FPGAs and ASICs - Fuzzy Modeling and Control: Theory and Applications - page 227

Fig. 13.1 Components of the Xfuzzy environment. Xfuzzy integrates a set of tools that facilitate the
different stages involved in the design process of fuzzy logic-based inference systems. These tools
share a formal specification language, XFL3, which allows describing complex hierarchical fuzzy
systems and defining the fuzzy operators required to implement them
tion. Section 13.6 illustrates the application of this design flow to a classical control
problem. Finally, main conclusions of this work are summarized in Sect. 13.7 .
13.2 Xfuzzy : A Development Environment for Fuzzy Systems
The Xfuzzy development environment integrates a set of tools that facilitate the
several stages involved in the design process of fuzzy logic-based inference systems,
from their initial specification to the final implementation (Baturone et al. 2007 ). In
addition to description, verification, and tuning tools, which allow the definition, test,
and optimization of fuzzy systems, the environment also includes synthesis tools that
provide software and hardware implementations of the system under development.
As shown in Fig. 13.1 , all the Xfuzzy 's tools share a common specification language.
XFL3 divides the description of a fuzzy system into two parts: the logical definition
of the system structure and the mathematical definition of the fuzzy functions. The
formal syntax provided by the language allows defining hierarchical fuzzy systems,
which combine crisp blocks and fuzzy rule bases that can express complex rela-
tionships among linguistic variables by using connectives and linguistic hedges. The
user can define its own fuzzy operators and use them as membership functions, fuzzy
connectives, linguistic hedges, crisp blocks and defuzzification methods (Moreno-
Velo et al. 2008 ). Fuzzy rule bases can be manually defined, taking into account