Maritime simulator based determination of minimum DCPA and TCPA in head-on ship-to-ship collision avoidance in confined waters

Abstract

Head-on collision between ships is one of the most dangerous issues in navigational safety problems. A tangible method for the determination of minimum DCPA (Distance at the Closest Point of Approach) and minimum TCPA (Time to the Closest Point of Approach) in head-on collision avoidance in confined waters is crucial. Firstly, this study develops an effective method to identify the ship interaction data from numerous MSBD (Maritime Simulation-based Data) and AIS (Automatic Identification System) data. These identified ship interaction data contain the information of how navigators avoid ship-to-ship collision risk. Secondly, we formulate the minimum DCPA and TCPA, implicitly indicating the highest navigational risk that is acceptable to a captain. The minimum DCPA and TCPA are difficult to be estimated from the AIS data because captains seldom encounter the critical situations in which two ships nearly collide in practice. Finally, to obtain the necessary MSBD for calculation and analyses, eight senior captains of more than ten years of sailing experience conduct a series of maritime simulator-based experiments in the Singapore Strait. Based on MSBD, we show how captains take action when faced with collision risk and when captains return course after reducing collision risk.