The Strainstall DockAlert system is designed to provide both the jetty operators and the ship's pilot and crew with a continuous, real-time readout of the vessel's speed of approach, angle of approach and distance from the berth.

This is achieved by two sensors mounted at each end of the berth that transmit laser beams towards the incoming vessel and receive reflections back from the bow and stern.

From these signals the system is able to calculate simultaneously the respective approach speeds and distances from the berth.

This data is transmitted to the berthing manager's control room and to a large digit display (3m by 2.5m) mounted adjacent to the berth that is visible from the ship's bridge at all times. The system provides distance accuracies of within 1cm and speed measurements within 1cm/s.

The Strainstall MoorAlert system measures and records the tension in vessel mooring lines and thereby detects any changes in the predetermined values caused by the action of wind, tide and wash from passing ships. Data from the system enables the berthing manager or the vessel master to continuously assess the efficiency of the mooring pattern and to take appropriate action to ensure that maximum mooring safety is maintained at all times. The requirement for standby tugs in uncertain weather conditions is minimised, as is the risk of partial or total break-out. Prevailing environmental conditions such as wind and current speed and direction are measured and the data displayed alongside those of the other sub-systems on the operator's terminal.

Signals from DockAlert, MoorAlert and the environmental package are handled by Berth Manager, Strainstall's Windows NT based software/hardware suite. Berth Manager not only logs and records the data from the two systems but also provides on-screen, real-time graphic display of a vessel's approach and, when berthed, the current mooring status of each and every mooring line. Furthermore, the alarm parameters for each line can be individually changed as required.

In addition to its 'real-time' duties, Berth Manager allows a wide range of analysis functions to be carried out as the system retains the data on each ship that has used the berth. At the Jurong facility, Berth Manager stations were provided for each berth but it is possible for one station to assume control of the other berth or both berths should the need arise.

MJ Information No: 18362