Nonlinear adaptive switching control for a class of non-affine nonlinear systems

This figure presents the structure of a nonlinear adaptive switching control system. In this system, an improved nonlinear adaptive control approach is proposed to relax the assumption on the higher order nonlinear terms of a class of discrete-time non-affine nonlinear plants described by the NARMA form. The proposed control strategy is composed of a linear adaptive controller, a neural network (NN) based nonlinear adaptive controller and a switching mechanism. An incremental model is employed to describe the nonlinear systems and an improved robust adaptive law is put forward for the linear adaptive controller. Based on the identification errors of the linear and nonlinear models, a new switching criterion is designed to select the proper controller. Using this control scheme, all the signals in the system are proved to be bounded. Simulation results are presented to demonstrate the effectiveness of the proposed control law.