Dynamic positioning (DP) holds a vessel at a defined location or on a pre-determined track against the forces of wind, wave, tide and current using its own propulsion and manoeuvring systems. It is used wherever anchoring is not possible or not desirable, or where very accurate positioning is required.
A dynamically positioned vessel is defined as one which automatically maintains its positioning, at a fixed location or on a predetermined track by means of thruster force.
In practice this is a system to automatically maintain a ship’s position and heading by using propellers, rudders and thrusters in various combinations despite wind, waves, and current trying to move the vessel away from the desired position or track.
Position references such as GPS, gyrocompasses, wind sensors and motion sensors provide data to the control systems for the propulsion and manoeuvring system.
Dynamic positioning systems meet IMO requirements for DP standards DP1, DP2 and DP3, involving increasing levels of system redundancy, together with the associated classification society rules.
The complete installation for a dynamic positioning system comprises:
Rolls-Royce supplies and supports all these systems, and offers a range of comprehensive training courses.
Rolls-Royce also manufactures independent joystick based positioning systems for vessels that require position holding ability but are not subject to full DP requirements.