An empirical ship domain based on evasive maneuver and perceived collision risk

TLDR

The paper introduces a new ship domain concept and analytical framework, and outlines future applications for waterway safety assessment and navigational decision support to reduce ship‑ship collision risk. The framework defines ship domain using the first evasive maneuver point, correlating it with perceived collision risk via available maneuvering margin detected through turning point identification and intention estimation, and applies this to AIS data in the Northern Baltic Sea to construct separate domains for give‑way and stand‑on vessels. Empirical analysis of AIS data shows that this dynamic, maneuver‑based ship domain, which incorporates encounter dynamics and navigator evasive actions, outperforms proximity‑based models and offers advantages and limitations discussed by the authors.

Abstract

This paper introduced a new ship domain concept and an analytical framework. The ship domain takes the point of the ship's first evasive maneuver as a basis and correlates it with the navigator-perceived collision risk level. The first evasive maneuver of a ship is detected based on the ship turning point identification and ship intention estimation. The available maneuvering margin (AMM) is utilized as a proxy to measure the perceived collision risk by the navigator. Interpreting the first evasive maneuver in terms of this AMM over a large sample of vessel encounters taken from automatic identification system (AIS) data finally enables an empirical estimation of the size of this ship domain. The method is applied to AIS data in the Northern Baltic Sea, and separate ship domains are constructed for the give-way and stand-on vessels with different maneuverability characteristics. Compared to the existing proximity-based ship domain, this ship domain explicitly incorporates the dynamic nature of the encounter process and the navigator's evasive maneuvers. Several advantages of this proposed ship domain concept and limitations of the presented modeling approach are discussed. Finally, possible future applications are explained, including waterway safety assessment and navigational decision support systems to reduce ship-ship collision risk.