Consumption-reduced manual and automatic manoeuvring with conventional vessels

Abstract

Conventional ships are rarely the focus of research projects on autonomous shipping. Nevertheless, the shipping companies are very interested in reducing fuel consumption. This paper proposes a gradual approach towards ship automation which starts with the intelligent assistance of common manual steering by means of a Maneuver Assistance System (MAS). The MAS displays a manually improved manoeuvre plan and the future motion based on the current actuator commands. These two assistance functions contribute to a more conscious use of actuators which can significantly reduce power consumption. For further automation, the improved manoeuvre plan is converted into a trajectory by forward simulation, which is then used by a control system. The control system includes feed-forward and feedback control as well as an allocation system based on a simplified dynamic motion model. A cascaded structure is used, where an outer track controller provides velocity and heading commands to an inner velocity and heading controller. The paper presents the necessary framework and the application of this approach to the digitised German research vessel DENEB with the aim to gradually introduce and realise automatic manoeuvring. Results from manual and assisted manoeuvres with the DENEB are analysed and compared. Finally, first results of automatic berthing with the vessel in the port of Rostock are presented.