No abstract

The article investigates the problem of collision avoidance of a group of ships offshore. To solve this problem it is necessary to ensure the cooperative maneuvering of several vessels from the group. The article looks into the case of unmanned ships, when each vessel is operated automatically. The use of unmanned technologies can eliminate the human factor on the safety of navigation. For this, it is necessary to develop reliable ship control algorithms in automatic mode.The publication proposes an algorithm for solving this problem. To this end, from the total amount of vessels in a given area we distinguish between the subsets of dangerous ships, privileged vessels, vessels obliged to maneuver, and ships that restrict the scope of solution. A method for constructing these subsets is described. A subset of dangerous ships is constructed by pair wise assessing the danger of rapprochement of each vessel with the rest of the vessels from the group. For this, it is necessary to synthesize forecasts of the trajectories of all vessels in the water area. A risk scale and an algorithm for estimate the collision of ships are proposed. A number of dangerously moving ships are divided into two subsets: privileged vessels and vessels obliged to maneuver. A safe divergence must be ensured by maneuvering these vessels. The remaining vessels in the water area are restrictions when seeking a solution. In the case where no solution can be found, a procedure to reduce the restrictions by moving ships from one set to another and re-searching for solutions is proposed. The final answer can be a set of changed routes for vessels obliged to maneuver.To carry out cooperative action is necessary to ensure the exchange of information between the automatic agents. This topic is also touched upon in the article. For citation:Smolentsev, Sergey V., Anatolii E. Sazonov, and Yurii M. Iskanderov. "Cooperative maneuvering of unmanned ships for collision avoidance at sea." Vestnik Gosudarstvennogo universiteta morskogo i rechnogo flota imeni admirala S. O.

The problem of collision avoidance of a group of ships offshore is investigated in the paper. To solve this problem it is necessary to ensure the cooperative maneuvering of several vessels from the group. The case of unmanned (autonomous) ships, when each vessel is operated automatically, is considered in the paper. The main attention is paid to the problem of equally understanding of the current navigation situation conditions by the various agents, jointly solving the problem of cooperative maneuvering in a given water area. To solve the problem of cooperative maneuvering, all agents operating unmanned ships must equally interpret the current navigational situation. Factors defining the current navigation situation are divided into two groups: the main factors necessary to solve the problem of collision avoidance under ideal conditions and additional factors that must be additionally taken into account when solving the problem of collision avoidance in the real navigation environment. Failure to take into account the additional factors can lead to inadequate decisions on the vessel management. The concept of context is introduced as a set of interpretations of the additional factors values. The importance of taking these factors into account when solving the problem of collision avoidance is shown. A list of factors, as well as an example of these factors interpretation for inclusion in the context, is given. Using the same context by all agents will allow them to equally interpret the current navigational situation in the navigation area and jointly solve the problem of cooperative maneuvering. The main properties of the context, such as universality and compactness, are defined. In the protocol of agents interaction, it is necessary to provide the special means for exchange and matching of the contexts between the agents operating unmanned ships.

ВведениеОдним из основных аспектов безопасности мореплавания является обеспечение безопасно-сти расхождения судов в море. Для решения проблемы предупреждения столкновений в 1972 г. была принята Конвенция о Международных правилах предупреждения столкновений судов в море, приложением к которой являются Правила МППСС-72 [1], выполнение которых является обязательным для гражданских судов. Однако применение этих правил не гарантирует безопасно-сти мореплавания, поскольку МППСС не учитывают навигационных ограничений в районе пла-вания, регламентируют расхождение двух судов, но неприменимы в случае встречи нескольких судов.Таким образом, использование только МППСС не позволяет обеспечить безопасность мо-реплавания в узкостях, где в настоящее время скапливаются большие судовые потоки. В усло-виях большого количества окружающих судов-целей судоводитель физически не может само-стоятельно оценить навигационную обстановку и принять правильное решение по управлению своим судном. Решением данной проблемы является создание автоматизированной системы пред-упреждения столкновений судов. Рассмотрение различных аспектов подобных систем содержится в литературе

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.