Fuzzy & ANFIS based temperature control of water bath system

Conventional controllers usually require a prior knowledge of mathematical modeling of the process. The inaccuracy of mathematical modeling degrades the performance of the process, especially for non-linear and complex control problem. To overcome above difficulties intelligent controllers like Fuzzy Logic (FL) and Adaptive Neuro-Fuzzy Inference System (ANFIS), are implemented. The Fuzzy controller is designed to work with knowledge in the form of linguistic control rules. But the translation of these linguistic rules into the framework of fuzzy set theory depends on the choice of certain parameters, for which no formal method is known. It is analyzed that ANFIS is best suitable for adaptive temperature control of above system. As compared to FLC, ANFIS produces a stable control signal. It has much better temperature tracking capability with almost zero overshoot and minimum absolute error.