Development of fuzzy logic controller for DC motor using personal computer and inexpensive microcontroller

Today, despite of the development of various types of electric motors, the traditional DC motors are still widely used in robotic and industrial applications because this type of electric motors has a high control quality. Moreover, the DC motor drives are simple and easy for deploying novel control algorithms. This paper describes the steps of development of a fuzzy logic controller for the speed control of a separately excited DC motor based on the use of a personal computer (PC) and an inexpensive 8-bit AVR Atmegalô microcontroller. The main advantage of the design of a fuzzy logic controller is that it does not require the mathematical model of the controlled object and is mainly based on the operator´s experience. In this control system, the PC is used as a virtual measurement and control environment. Meanwhile, the microcontroller is programmed for the RS232 communication protocol and creating the Pulse Width Modulation (PWM) signal fed to the semiconductor switch in the power circuit. An experimental comparison between the performance of the fuzzy logic controller and the Proportional-Integral-Derivative (PID) controller is also carried out. The experimental results obtained show that the fuzzy logic controller outperforms the PID controller in terms of the significant reduction of the overshoot.