A Simple Analytical Model of Ship Movement

Abstract

The problem of synthesis of the vessel trajectory is discussed in the paper. The solution of this problem is important for the development of automatic ship control systems. In particular, it is solved in the system of automatic collision avoidance systems. One of this system components is the ship's movement modeling subsystem. This subsystem synthesizes the prediction of the movement trajectory of both own vessel and target ships in the water area. An analytical model of the vessel movement when maneuvering the course and speed is proposed in the paper. The trajectory of the vessel movement when maneuvering the course is divided into four segments. Each segment is characterized by a set of parameters. The values of these parameters for each particular vessel should be determined in advance. This requires the identification of model parameters. The proposed model of vessel dynamics during speed maneuver is the result of analytical solution of the differential equations of the vessel movement during deceleration or acceleration. Using this model, it is possible to obtain the parameters of the vessel's movement at any time after the start of the speed maneuver. Previously, the authors have proposed a kinematics model of the vessel movement during maneuvering. However, this model was integrating-to obtain the parameters of the vessel's movement at a given time, the parameters for the intermediate positions of the vessel with a fixed step were necessary to calculate. The advantage of the proposed model is that it allows analytically calculating the vessel motion parameters for any given moment of time, which lets to find solutions faster, especially in case of processing a large number of trajectories. The identification issues of model parameters are considered. The method to identify the vessel's dynamics model parameters according to the data from the maneuvering booklet is used. The maneuvering booklet contains the information on the vessel behavior when performing the standard maneuvers the course and the speed. Its presence on the vessel is required in accordance with IMO Resolution A.601 (15). The proposed model of vessel dynamics allows one to obtain the vessel motion parameters at any given time after the maneuver start or to calculate the arrival time at a given point of the maneuver trajectory. It can be used in the vessels collision avoidance systems and any other control systems where to predict the vessel movement during maneuvering is necessary.

Static Obstacles Avoidance Algorithm for Unmanned Ship

“…К последним относятся вопросы, связанные с разработкой системы управления движением БЭС, которым посвящено большое количество работ. В частности, в работе [6] решается задача синтеза траектории движения судна, принципы построения алгоритмов управления БЭС в акватории порта рассмотрены в статье [7], в работе [8] исследована гибридная система управления движением БЭС в заданную точу.…”