Fuzzy Feedback Linearizing Controller and its Equivalence with the Fuzzy Nonlinear Internal Model Control Structure
Abstract
This paper examines the inverse control problem of nonlinear systems with stable dynamics using a fuzzy modeling approach. Indeed, based on the ability of fuzzy systems to approximate any nonlinear mapping, the nonlinear system is represented by a Takagi-Sugeno (TS) fuzzy system, which is then inverted for designing the fuzzy controller. As an application of the proposed inverse control methodology, two popular control structures, namely feedback linearization and Nonlinear InternalModel Control (NIMC) structures, are investigated. Moreover, the paper points out that, under some conditions, both control structures are equivalent and naturally implement a Smith predictor in presence of time delays.