Adaptive fuzzy funnel control for nonlinear systems with input deadzone and saturation.

This paper, for the first time, focuses on the problem of funnel control for strict-feedback systems with input deadzone and saturation, simultaneously. A new smooth function in non-affine form is firstly proposed to approximate the non-smooth input deadzone and saturation and transformed into an affine form by the mean-value theorem. The unknown nonlinear functions and external disturbances are estimated by fuzzy logic systems. An improved funnel error is given and embedded in the procedure of controller design. Based on the backstepping method, an adaptive fuzzy funnel controller is constructed, which guarantees that the output tracking error falls within a pre-set funnel and all the signals in the closed-loop system are semi-globally uniformly and ultimately bounded. Simulation results demonstrate the effectiveness of the developed controller. [ABSTRACT FROM AUTHOR]