A Study on the Initial Action of Navigators to Avoid Risk of Collision at Sea

Abstract

: The Convention on the international regulations for preventing collisions at sea, 1972(COLREGs) defines the collision avoidance principles and various navigation rules for the prevention of collision at sea. In particular, the initial responses to avoid risk of collision are mainly decided by navigation officer's experience and subjective judgement. However, collision accidents could be effectively prevented if the minimum criteria of quantitative initial response are suggested to the junior officers and the cadets who have insufficient sea experience and navigation competency. This study reviewed the COLREGs terms related to the initial response and the existing papers concerned with risk assessment model. A questionnaire survey is also carried out for safe passing distance, degrees of alternating course and initial response distance to avoid collision in accordance with various encounter situations. Base on these results, we propose the proper minimum safe passing distance between the vessels, the initial response distance and required turning angles for alternation in each encounter situations. The suggested criteria of initial response will contribute to the prevention of collision at sea as well as the improvement of gradual navigation technology.

Inference Rule of Collision Risk Index based on Ship Near-Collision via Adaptive Neuro Fuzzy Inference System

“…Comparing the minimum distance of the ship lighting with an encounter situation for an action of collision avoidance, the mast light and the side light are able to be checked on head-on and crossing situation, and the stern light are able to be checked on overtaking situation. Results of navigator's interviews [24] showed 6 nm, 3 nm and 1nm on the head-on situation, crossing and overtaking situation, and the minimum safe distance. Cockcorft, A. and Lameijer, J.N.F.,(2011) [25] advised the minimum safe distance for collision avoidance as 1 nm in sight of one another and 2 nm in restricted visibility.…”

Determining the Proper Times and Sufficient Actions for the Collision Avoidance of Navigator-Centered Ships in the Open Sea Using Artificial Neural Networks

“…We examined the subjective criteria for the initial evasive maneuver judgment of the navigators who had already learned the COLREG Rule 8 "Action to avoid collision". Lee et al [49] conducted a survey of 192 mariners, including captains, and the resulting minimum safe separation distances are detailed in Table 2. As shown in Table 2, seafarers perceived the minimum safe separation distance as 1.0 mile, and this trend was characterized by a higher percentage of respondents at lower ranks.…”

Algorithm Design of Navigation Intention Message Transmission for Collision Avoidance of Maritime Autonomous Surface Vehicle

“…In the first stage, the MASS continuously observes the movement of the target ships approaching the MASS during navigation, and judges whether the target ship is navigating within the range of the response of the collision avoidance based on the MASS. In order to determine the appropriate response distance, a study on the first-aid measures of the navigator [18] is used. Table-Ⅲ shows the response distance for the collision avoidance based on the navigation relation proposed by the COLREG.…”

“…In case the output, which can be shown as the risk of collision, exceeds the threshold value by using the calculated DCPA and TCPA as input variables, the MASS should be judged by continuously observing a relative bearing between the MASS and the target ship , and decides whether the MASS is a give-way ship or not. At this time, we use the results of Cockcorft [19] and the first-aid measure of the navigator to specify the threshold [18]. The suggested safe distance is 1 nautical mile and the time to spare for altering course is about 10 minutes.…”