Adaptive fuzzy dead-zone control for unknown nonlinear systems

Adaptive fuzzy control is used to control a class of unknown nonlinear systems with perturbed dead-zone input in this paper. A new dead-zone actuator model which contains time-varying and perturbed actuation gain is proposed. The dead-zone nonlinearity is treated as a linear term, a nonlinear term and a disturbance-like term. Nonlinearly parameterized fuzzy logic systems are used to approximate the unknown functions in the control design. The proposed control scheme ensures the stability of the closed-loop system and satisfactory tracking of the output to the given reference signal. A numerical example is included to show the effectiveness of the approach.