Modelling and Control of Thruster Assisted Position Mooring Systems for Ships

Abstract This paper adresses the mathematical modelling and control design of an automatic thruster assisted position mooring (POSMOOR) system. Such control systems are applied to anchored floating production offloading and storage vessels (FPSO's) and semi-subs. The POSMOOR controller is designed using model based control with a LQG feedback controller in conjunction with a Kalman filter. The controller design is in addition to the environmental loads accounting for the mooring forces acting on the vessel. This is reflected in the model structure and in the inclusion of new functionality.