A design methodology for adaptive type-2 fuzzy controllers

The main objective of the study is to provide a valid and effective methodology for the design and development of adaptive type-2 fuzzy controllers (AT2FLCs). The methodology is based on an in depth analysis of the process dynamics and the use of an Adaptive Neuro Fuzzy Inference System (ANFIS) technique for the optimization of controllers. The application of the methodology is shown in the design and development of AT2FLCs for two biochemical processes characterized by uncertainty and time varying parameters. The simulation results show that the union of the ANFIS optimization method with the adaptive fuzzy algorithm operating on the output scaling factor, allows to obtain robust AT2FLCs, with fewer rules than traditional type-2 FLCs, that minimize the negative effects of all system parameter changes and achieve in all cases a very high control performance.