Development of a Ship's Course Controller using μ-synthesis

Abstract

The article describes the procedure for designing a robust controller for controlling the course of sea vessels exposed to sea waves using µ-synthesis. To this end, practical knowledge of the vessel is used to obtain a linear design model with parametric uncertainties describing the dynamics of the vessel. Appropriate frequency weighting functions are selected to provide the required performance characteristics during the controller design phase. The proposed model and then the weighting functions are used to design a robust controller. The problem of wave filtering in the low-frequency range is also considered during the modeling and design of the controller. The key contribution of the paper is that it provides system designers with a methodology for obtaining uncertain linearized ship models that naturally fit within the framework of µ-synthesis control theory, and it describes, in a systematic manner, the various stages of the controller design process. In addition, the document contains detailed information on methods for analyzing robust systems and their modeling.