Dynamic positioning

Dynamic positioning (DP) is a computer controlled system for automatic positioning of a ship. It is also called a dynamic - positioning system (DPS).

Operation and design

The compensation of the movement is done with the help of their own propeller nacelles and propeller. Position reference sensors, combined with wind sensors, motion sensors and gyro compasses provide information for the computer with respect to the position of the vessel and the extent and direction of environmental forces available that influence its location. The DPS is normally operated with the support of a Differential Global Positioning System ( DGPS).

However, the DP is not limited to ships, submarines or semi-submersible, but is also used on Mobile Offshore Drilling Units ( MODU ).

The computer program contains a mathematical model of the vessel that contains information about the current wind and waves and the location of the engines of the ship contains. These data, combined with the sensor information of the computer to calculate the required steering angle of the thrust nozzle can use. This allows at sea, where a mooring or anchoring is not possible to hold a position or docking in ports.

Dynamic positioning may either be absolute - that is, that the ship is kept at a fixed point on the ground - or relative to a moving object such as a ship or an underwater vehicle. One can also ship at a favorable angle to wind direction, wave and current hold ( weathervaning ). Also an application together with an anchor system is possible.

Application

Dynamic positioning is often used in the offshore oil industry, for example in the North Sea, the Persian Gulf, Gulf of Mexico, West Africa and Brazil. Today there are more than 1000 vessels, which are equipped with such a system. The first ship with dynamic positioning system was built in 1974 Arctic Surveyor.