‘Manœuvres to Ensure the Avoidance of Collision’

219

107

Efficient marine navigation through obstructions is still one of the many problems faced by the mariner. Many accidents can be traced to human error, recently increased traffic densities and the average cruise speed of ships impedes the collision avoidance decision making process further in the sense that decisions have to be made in reduced time. It seems logical that the decision making process be computerised and automated as a step forward to reduce the risk of collision. This article reviews the development of collision avoidance techniques and path planning for ships, particularly when engaged in close range encounters. In addition, previously published works have been categorised and their shortcomings highlighted in order to identify the ' state of the art ' and issues in close range marine navigation. K E Y

Section: S T U D I E S I N C O L L I S I O N a V O I D A N C Ementioning

confidence: 99%

Review of Collision Avoidance and Path Planning Methods for Ships in Close Range Encounters

Tam

Bucknall

Greig³

2009

219

107

“…5 The present paper quantifies, and to some extent qualifies, the ideas expressed in that report, and should be read in conjunction with it. 5 The present paper quantifies, and to some extent qualifies, the ideas expressed in that report, and should be read in conjunction with it.…”

Section: Collision Avoidance In Amentioning

confidence: 68%

Collision Avoidance in a Traffic System

Calvert¹

1973

In 1960 Dr. Calvert published a paper in the Journal (13, 127) which proposed a fundamentally new conception of how to avoid collision between single craft at sea or in the air, based on work carried out by the Mathematics Department of the Royal Aircraft Establishment. Later Hollingdale (14, 243) published a rigorously mathematical explanation of Calvert's ideas. The following paper to some extent draws together the arguments that have ranged so widely over this subject during the last ten years or so.The chief criticism which has always been made against the existing Collision Regulations and is now being made against the revised ones, is that, except for the end-on encounter, no directives are given as to how a vessel should manœuvre to ‘keep out of the way’. Their role, it has been said, is not so much to prevent collisions as to enable lawyers to apportion blame after collision has occurred. The explanation usually given is that ‘the infinite variety of encounters which may arise at sea does not yield to a uniform treatment’.

“…It was to avoid this sort of thing that Calvert 3 proposed a very simple mathematical rule, that ships should always take such action as to make their sight-line move in an anti-clockwise direction. This proposal led to a great deal of argument and counter argument with no reference to replicable experimental data.…”

mentioning

confidence: 99%

The Avoidance of Accidents at Sea

Phillips

1975

The problem of collision avoidance at sea would be an important one even if accidents were rare, but the evidence suggests that they are much more common than one might expect. In the eight years leading up to May 1963 there were 60 collisions in the English Channel area and in the following eight years the number increased to 94. With the development of navigational aids such as radar one might have hoped for a decrease. The suggestion that the increase is quite likely attributable to the possession of radar is ironic indeed. It would appear that having the use of this ‘safety’ equipment allows the mariner to take greater risks, but that the risks which are in fact taken are greater than the equipment allows. We would do better to go back to fog horns alone. Even if over-confidence is not the only factor responsible for the increase in accidents, it does, nevertheless, illustrate the importance of the psychological variable in any man–machine system.Collisions at sea, however, are not simply due to errors in a man–machine system, It is, of course, the hardware that actually collides, but the cause of the interaction lies in the decisions and indecisions of the two human agents controlling the vessels. It is essentially a social encounter. It is for this reason that the work initiated by Captain Kemp is greatly to be welcomed.