Fuzzy logic control via an FPGA: a design using techniques from digital signal processing

Techniques from digital signal processing (DSP) have been used to perform some of the problematic operations needed in a fuzzy logic controller. These techniques have enabled the development of circuits which are not only compact but also scalable, so that we do not suffer as high a rate of increase of the use of resources as for conventional circuits when the accuracy of the controller or the number of inputs or membership functions is increased. Circuits have been developed so that a complete, reprogrammable fuzzy logic controller can be fitted into a medium-sized FPGA. This paper reports mainly the development of the rule evaluation circuits.