Ship Aautomation system network overview
The behavior of a human pilot in accomplishing the approaching maneuver of a small boat in a harbor using the leading line visual guidance method. In the proposed approach, two targets are arranged in cascade on the quayside and are detected by a CCD camera mounted on the bow of the boat. An image-processing algorithm is used to compute the heading deviation angle and tracking deviation angle of the boat with respect to the leading line passing through the centers of gravity of the two targetsThe experimental results performed using a small FRP boat in a real-world harbor have confirmed the ability of the proposed autopilot system to guide the boat in such a way that it converges toward the leading line and enters the designated pre-berthing region. To enable the autopilot system to determine the appropriate point at which to switch from an approach maneuver mode to a berthing control mode, a method has been proposed for computing the distance between the ship and the quay based on the perceived elevation angle of the rear target and the known separations of the front and rear targets in the horizontal and vertical directions, respectively. Whilst this result confirms the general feasibility of using the proposed range estimation scheme to determine the point at which to switch from an approach mode to a berthing control mode, it is clear that further work is required to improve the accuracy of the distance estimates such that they can be used for feedback purposes during the actual berthing procedure. This issue is presently under review by the current group and will be presented in the near future.