An adaptive fuzzy PID control for a class of uncertain nonlinear underactuated systems

Abstract : In this work an adaptive PID control law is used to approximate a model-based robust sliding mode control law to deal with a class of uncertain underactuated nonlinear systems. Therefore, a fuzzy system is used to learn online the ideal PID control gains regarding the desired performances. So, the fuzzy system parameters are adjusted online by a robust adaptation law in order to minimize the error between the unknown ideal controller and the PID controller. The stability of the closed-loop system is proven analytically based on the Lyapunov approach. A simulation example is presented to illustrate the efficiency of the proposed approach.