1. Field of the Invention
This invention regards a method of dynamic positioning of a vessel. More particularly, it regards a method that involves two or more floating buoys being coupled to a vessel by means of buoyancy, wherein the buoys are provided with positioning machinery. The buoys form part of a dynamic positioning system and are preferably provided with energy from a generator placed on the vessel.
2. Description of Related Art
When operating in relatively shallow waters offshore it is customary to use anchor based mooring methods. Anchor systems of this type reveal substantial flaws when it comes to anchoring a vessel at greater depths. The main reason for this is that the length of chain or steel cable required causes a weight-induced strain on the mooring that takes up a considerable share of the tensile strength of the mooring.
Thus it has become more and more common to equip vessels operating in deep waters with so-called dynamic positioning. Vessels such as drilling vessels, supply vessels, accommodation vessels or cargo vessels are to an increasing extent being equipped with this kind of equipment.
In addition to navigation and control systems, a dynamic positioning system also includes positioning machinery. It is essential that the vessel be equipped with positioning machinery that is arranged to exert a pushing force in at least two directions and in two positions on the vessel. Positioning machinery of this type typically includes several positioning thrusters that are generally arranged for rotation in the horizontal plane, so as to allow them to exert a pushing force in any horizontal direction.
For vessels originally built to use conventional anchor system, the conversion required to allow them to use dynamic positioning has proven to be a relatively complex and costly process.