Multi criteria route selection with custom domain shape

The paper describes a multi criteria vessel route selection system designed to support VTS systems. The system is comprised of three cooperating modules: simulation, collision risk estimation and multi criteria decision making. Given the set of alternative routes, the initial and goal positions and velocities of own and target ships the output of the system is a ranking of all considered routes. This ranking enables the VTS operator to produce a proper route recommendation which is then sent to the navigators. The additional advantage of the system described here is its ability to support custom shape of ship domain

Evolutionary sets of cooperating ship trajectories : COLREGS compliance

The paper presents a newly designed improvement to the method of solving multi-ship encounter situations. In general, the method combines some of the assumptions of game theory with evolutionary programming and aims to find optimal set of cooperating trajectories of all ships involved in an encounter situation. The improvement presented here is a new way of modelling some of the COLREGS rules. Due to this change, the method is now able to find solutions, which are more compliant with COLREGS, more intuitive and consequently – safer from the navigator’s point of view

Adopted isochrones method improving ship safety in weather routing with evolutionary approach

The paper is focused on adaptation of an isochrones method necessary for application to a weather routing system with evolutionary approach. Authors propose an adaptation of the isochrones method with area partitioning assuring that the route found by the adopted method would not cross land. In result, when applied to a weather routing system with evolutionary approach, this proposal facilitates creation of initial population, resulting with routes of reduced collision risk and low costs of passage

A Simulative Comparison of Ship Domains and Their Polygonal Approximations

The paper investigates the impact of a precise ship domain shape on the size of collision avoidance manoeuvres. The considered collision avoidance manoeuvres include both course and speed alterations. Various ship domains are compared with their polygonal approximations, which vary in the number of points of a domain contour and placement of these points. The best of all considered approximations is determined in the course of simulation experiments performed for head-on, crossing and overtaking situations. The chosen number and placement of contour points combine precision of domain approximation with reasonable computational time