Collision Avoidance at Sea in the Mid-20th Century

Abstract

In the middle years of the 20th Century, few merchant ships were fitted with radar and, on those that were, shipmasters often looked upon it as a distraction from a watchkeeper's proper duties rather than as a useful aid to navigation.For shipmasters of that persuasion, the only place to keep watch was outside the wheelhouse on an exposed bridge wing; mostly the starboard wing because the COLREGS (‘Collision Regulations’ or, more properly, ‘The International Regulations for Preventing Collisions at Sea’) required us to give way to ships approaching from the starboard side. Well, the bridge wing was an attractive place to spend a few hours on a calm, tropical night, but it could be highly disagreeable and sometimes, I thought, actually dangerous, in a North Atlantic rainstorm.

Obstacle Avoidance Approaches for Autonomous Navigation of Unmanned Surface Vehicles

“…With regards to technology advancements, the methods for collision identification have dramatically changed in the last fifty years (Kemp et al, 2012) and sensor advantages and limitations are summarised in Table 1.…”

“…With regards to technology advancements, the methods for collision identification have dramatically changed in the last fifty years (Kemp et al, 2012) and sensor advantages and limitations are summarised in Table 1. In Almeida, et al (2009) a radar classifies targets in terms of a collision threat. A set of perimeters ( Figure 2) is defined around the USV: irrelevant (3 km), safe (500 m), warning (250 m) and prohibition perimeter (50 m).…”