Analysis and electronic implementation of a fuzzy system for the control of a liquid tank

This paper presents a comparative study between a fuzzy system and a PI conventional controller for the real control of a liquid tank. The final fuzzy system is electronically implemented in a low-cost multifunction microcontroller, the PIC16C71. For non linear problems, fuzzy systems are useful tools: as shown in this paper, the performance of the fuzzy controller is superior to that of conventional methods. There are various means of implementing the transfer characteristic of a controller. As will be discussed in this paper, the division of the output surface into different planes is the optimum solution, as this requires the least amount of memory (420 lines in PIC assembler language). The final structure of the autonomous system is very compact.