Design and implementation of Fuzzy logic controller for a DC motor

Design of a Fuzzy Logic Controller (FLC) requires more design decisions than usual, for example rule base, inference engine, defuzzification, and data preand post processing. This project is a humble effort to implement an FLC using VHDL for motor control. There are three parts to fuzzy controller, the fuzzification of the inputs, the defuzzification of the outputs, and the rule base. The controller that is implemented here demonstrates a 1-input, 1output fuzzy controller with 7-membership functions. Here a VHDL-based design and synthesis approach is used for designing which has considerably reduced the design time. A complete description of the controller A fuzzier, defuzzifier and a rule base are written in VHDL and are logically integrated which is further synthesized using logic synthesis tool XILINX ISE9.2i software. The efficiency of the implementation is verified using FPGA. In this paper, the concept of Fuzzy Logic is used to control the speed of a simple DC motor. The hardware descriptive language used for the purpose of design of the Fuzzy Logic Controller is VHSIC Hardware Descriptive Language (VHDL) and is implemented on SPARTAN-3 FPGA hardware. This method of speed control of a dc motor may represent an ideal application for introducing the concepts of fuzzy logic. Here a sincere effort is made to show, how a fuzzy controller can be used to control the motor speed, which represents a very practical class of engineering problems.