General cargo ships are the most numerous in the merchant fleet. In these vessels, the stowage and securing of non-standardized cargo must be designed prior to being shipped. Furthermore, during sea navigation, the shipmaster must be confident that the secured cargo is safe in any weather conditions. One of the goals of the present research is to provide helpful guides to ship operators about the optimal navigational parameters. Despite different criteria being followed by the shipping industry to calculate the rolling motion accelerations, relevant accidents and losses related to an inadequate securing arrangement still occur. Firstly, this paper analyzes and compares the IMO’s and classification societies’ criteria, obtaining relevant results about the different safety levels along the ship’s dimensions. Secondly, it obtains a novel mathematical model of angular transverse acceleration, considering the sea state conditions and navigational parameters. For this reason, it investigates the combinations of optimization of these parameters. Finally, it proposes novel 3D surface graphs as being easy, useful, and quick to be interpreted by shipmasters when sailing in certain sea state conditions, to know if the limits of the maximum securing arrangement are exceeded and predict the ship’s optimal speed and heading in order to set out.

Ship maneuvering in ports is increasingly reduced because the increase in ship size is not proportional to the increase in port areas. Furthermore, the number of assisted vessels and the need for tugboats working in densely populated areas make it necessary to reduce the number of involved tugboats, reducing pollution and costs. Therefore, shiphandlers must know, in addition to the pivot point, the center of lateral resistance under any circumstance to optimize the assistance from tugboats and improve maritime navigation. From the literature, it is evident that the practical determination of the center of lateral resistance is still unknown. This paper aims to propose novel mathematical models to identify the position of this point and the most important variables that determine its position. For that, data of different ships in different conditions were obtained from a full mission bridge simulator. Afterwards, 15 novel mathematical models were developed, making use of artificial intelligence tools and training neural networks. The high determination factor reached in some models shows the accuracy of the obtained models. One advantage of the presented models is that they are very easy to be applied by shiphandlers, because highly well-known parameters are involved. Moreover, original 3D charts showing the combination of the input variables were generated to identify the map of the whole process. The very simple new models obtained and the novel 3D charts shown in the present paper can be considered useful and applicable by the shiphandlers of most of the merchant fleet to improve the efficiency and safety of maritime navigation in increasingly restricted waters.

In recent years, both the number and the size of ships have increased considerably, whereas port areas have expanded much more slowly. As a result, port manoeuvres are increasingly performed in restricted waters, which increases navigational risk during ship operations. For this reason, ship-handlers must know the instantaneous position of the pivot point (PP) at any time. The aim of this paper is to propose novel mathematical models to determine the PP’s position and to identify the most relevant variables influencing it. For this purpose, a full-mission bridge simulator was used to generate a dataset based on multiple simulations performed under different combinations of rudder angles and engine telegraph orders. First, a new trigonometric formulation is proposed to determine the instantaneous position of the PP using only directly measurable variables, namely the speed through water and the transverse velocities at the bow and stern. Subsequently, additional predictive models were developed using Design of Experiments (DOE) and response surface techniques. These models achieve high predictive accuracy while remaining simple enough to be applied in practical ship-handling scenarios. The resulting models can assist ship-handlers in anticipating PP behaviour and improving manoeuvring safety, particularly in restricted waters. Original 3D charts showing the combination of several input variables are included to identify the map of the whole process.