Frequency domain singleton fuzzification in the design of fuzzy logic controllers

In this paper, an alternative approach for implementing singleton fuzzification in fuzzy controllers is presented. Fuzzification is translated to the frequency domain by means of a frequency-modulated-sinusoid signal, whose spectral representation is a Dirac´s delta function (singleton fuzzifier). This sinusoid is applied to a non recursive filter which is considered as a membership function generator. This approach facilitates the on line reconfiguration of membership functions in hardware based fuzzy controllers. Two control problems are presented where frequency domain singleton fuzzification has been used.