The Research Of The Four Degrees Of Freedom Maneuverability Of Large Container Ships In Port With The Assistance Of The Tug

With development of container ship enlargement, the problem of maneuverability is being highlighted gradually, which is especially reflected in narrow channel of the port. For the characteristics of the large container ship itself, its center of gravity is generally high, when the ship is fully loaded, the lateral area is large, and the ship is easily influenced by external factors, such as wind, current and etc. It’s difficult for the ship to overcome by self-vessel operation in shallow water with low speed, and it’s necessary to require for tug assistance under this condition. Referring relevant studies domestic and aboard and considering the characteristic that the container vessel will generate a larger heeling angle when it is turning in full rudder angle, MMG thought is adopted to establish a more comprehensive ship’s motion model of large container vessel with four degrees of freedom including rolling which purpose is to improve the accuracy of ship motion simulation and the calculation model of tug force is added to it. Then the MATLAB software is used for analog simulation of the manipulation of the large container vessel within the port under the assistance of the tug. Comparing the data of turning simulation and the data from the real ship trial, the accuracy of the established model is verified.This article studies the maneuverability in port and the law of motion when the large container ship is fully loaded. According to the established motion model, the ship’s motion with residual speed control, turning with downstream, transverse shifting and other conditions are stimulated, and the ship handling key points are analyzed quantitatively and qualitatively respectively based on the output results.The result of this article may help the marine navigator to learn more about the characteristics of maneuverability of the large container ship, and may provide theoretical reference in handling large container ships in the port in actual production, and may also provide theoretical reference for improvement of the ship’s motion model of large container vessels in the navigation simulator.