Adaptive dynamic safety domain for different sailing conditions

Abstract

The problem of navigation safety is considered, in particular, the problem of developing an algorithm for an adaptive dynamic safety domain for various navigation conditions is investigated. The risk assessment of a ship approach situation is based on the safety domain as the minimum area around the ship into which an oncoming ship should not enter. Navigation conditions are considered in accordance with the rules of COLREG‑72 for navigation of vessels with limited visibility and being in sight of each other. To solve this problem, the navigation areas are classified. For further analysis, a table for the conditions and areas of navigation to identify the shape of the domains is created. The hydro meteorological situation, which takes into account the navigation conditions, and as a consequence, the need to increase the size of the safety domain, is considered. Changes in the parameters and shape of ship safety domains for different navigation conditions have been identified. For each district and navigation conditions, an original configuration of the security domain is proposed. The dynamic changes of the domain during movement in traffic separation systems and channels are separately considered. Using an example, a situation when the bow of the domain crosses the dividing line, which can lead to the appearance of false dangerous targets, is simulated. To avoid such situations, a dynamic domain with a changing shape in the form of an ellipse for swimming in a traffic separation system and channels, taking into account sailing conditions with limited visibility and in sight of each other is proposed. For the calculation, an algorithm to determine the shape of the domain under different visibility conditions and navigation areas has been compiled. Calculations for the case when the vessel enters a turn in traffic separation systems and narrow spaces have been performed. The deformation of the domain during rotation is shown.