A Study on the Collision Avoidance System of a Ship Considering the Effects of Speed Dependent Coefficients

The collision avoidance procedure of a ship can be divided into three categories: detects environment and accesses the degree of the collision risk; establishes navigation plan and executes a control command to perform the established plan; returns to her original path when collision risk disappears. We can obtain own ship’s speed and rudder angle to avoid the ship collision through the expert system. Generally, when a ship voyages in harbor and channel, the ship’s speed should be decreased because of the environmental restricts. In this paper, using maneuvering coefficients obtained from PMM tests with a cruise ship model at three speeds (23.5knots, 19.5knots, and 11.5knots), we simulate 20/20 zigzag and Steady turning maneuvers. After K and T indices are obtained by analyzing the 20/20 zigzag simulation results, we investigate the effects of speed dependent coefficients on the maneuvering trajectories. After these procedure, traces of ships which controlled by the collision avoidance system are analyzed.