Collision risk identification method of vessel restricted in her ability to maneuver based on multi-level ship domain

This study proposes a collision-risk identification method based on a multi-level ship domain for vessels with restricted maneuverability. Multiple domain models are defined to detect collision risks posed by passing ships. To better illustrate how these risks evolve, a grid-based visualization method is introduced. This approach systematically categorizes collision risk within the vessel’s surrounding waters and provides corresponding visual identification schemes. Experimental results show that the method offers stronger risk-identification capability than a single ship-domain boundary and enables effective visualization of risk trends between restricted-maneuverability vessels and passing ships. Overall, the method expands current approaches to collision-risk assessment for vessels with limited maneuverability and addresses a key challenge in navigation-safety supervision.