Robust fuzzy controller design for model-based discrete ship steering systems subject to multiple variance constraints

Abstract

This paper presents a fuzzy controller design method based on Takagi-Sugeno fuzzy model for controlling the Nomoto's ship steering systems with nonlinearities. The state variance and output variance constraints are considered for the stochastic behaviors in Nomoto's ship steering model. Also, the state uncertain dynamic is considered, which can be solved by robust control theory. In this paper, a controller is designed by parallel distributed compensation method with satisfying the Lyapunov stability conditions and multiple variance constraints. Finally, the stability conditions are effectively solved by recasting into so-called linear matrix inequality problems. At last, a simulation is provided for the nonlinear ship steering systems whenever the external disturbances and perturbations exist.