December 2024
An Uninterruptible Power Supply (UPS) is a low-voltage system designed to provide a secure and continuous power supply to critical systems, including Dynamic Positioning (DP) control elements and other essential vessel functions. Equipped with a battery backup, a UPS ensures operational continuity during power interruptions or fluctuations, protecting sensitive equipment from damage or failure.
An Umbilical is a critical tether used in subsea operations to connect a diver, Diving Bell, Remotely Operated Vehicle (ROV), or other underwater equipment to the support vessel or platform. It serves as a conduit for vital resources and communications, ensuring operational efficiency and safety in underwater environments.
Tunnel Thrusters are propulsion units installed at the bow or stern of a vessel. Encased in a tunnel structure within the hull, they generate thrust in an athwartships (side-to-side) direction, providing precise lateral control for maneuvers such as docking, mooring, or station-keeping in Dynamic Positioning (DP) operations.
Triplex refers to a Dynamic Positioning (DP) system configuration that incorporates three computers working in parallel to provide redundancy. This setup uses voting logic to ensure that the system remains operational even in the event of a failure in one computer, enhancing safety and reliability during critical offshore operations.
A Transponder is a subsea device used in conjunction with Hydroacoustic Position Reference (HPR) systems. Mounted on the seafloor or attached to subsea equipment, the transponder operates in an interrogation-reply mode. When acoustically interrogated by a vessel-mounted transducer, it responds with an acoustic signal, enabling precise positional calculations.
A Transducer is an acoustic probe mounted on the bottom of a vessel, serving as a critical component of the Hydroacoustic Position Reference (HPR) system. It transmits and receives acoustic signals to and from subsea transponders, enabling precise positioning for Dynamic Positioning (DP) and other offshore operations.
Track Follow or Autotrack is a Dynamic Positioning (DP) function that enables a vessel to automatically navigate along a predefined track composed of waypoints. The DP operator inputs the track details, including coordinates, speed, and optional timing, into the DP system, which then controls the vessel's movement to maintain precise adherence to the planned route.
The Touchdown Point refers to the specific location on the seafloor where a cable or pipe first makes contact during laying operations. This point is vital for ensuring accurate placement, structural integrity, and alignment of the cable or pipe along its intended route. Precise monitoring of the touchdown point is crucial in offshore operations to maintain control and avoid environmental or operational complications.
The Thruster Exclusion Zone refers to an azimuth sector or range of sectors where the output of azimuth thrusters is either prohibited or limited. This functionality, also known as Azimuth Barring or Prohibited Azimuth Zone, is critical for maintaining safe and efficient operations in Dynamic Positioning (DP) systems. These zones can be defined to avoid adverse effects of thruster wash on sensitive equipment, structures, or other operational elements.
Thruster Bias is a Dynamic Positioning (DP) system function that allows two thrusters to work in opposition, as directed by the DP operator. This feature can be used strategically in certain operational scenarios, such as minimizing azimuth hunting in calm conditions or increasing power loads for operational or testing purposes.
