Page 353 - Introduction to Marine Engineering

Instrumentation and control 325

Integrated control

The various control and monitoring systems described so far may be
integrated in order to enable more efficient ship operation and reduce
manning. Machinery control systems are being combined with
navigation and cargo control systems to bring about 'Efficient Ship'
integrated control systems. Combining previously separate sources of
data regarding, for example, ship speed and fuel consumption, enables
optimising of ship or engine operating parameters,
An Integrated Control System would be made up of a Bridge System,
a Cargo Control System, a Machinery Control System and possibly a Ship
Management System.
The Bridge System would include an automatic radar plotting aid
display, an electronic chart table, an autopilot, a gyro, log, and echo
sounder. The Cargo Control System will vary according to the type of
vessel, but will enable loading calculations, cargo management, ballast
control and data logging. The Machinery Control System will combine
various control systems to enable surveillance to UMS requirements,
performance and condition monitoring, generator control and
automatic data logging. Ship Management would involve administrative
record keeping, word processing, stock control and maintenance
planning.
Workstations with computers, monitors and keyboards would be
provided in the appropriate locations, such as the machinery control
room,, on the bridge, in the cargo control room and various ship's
offices. A network would connect the various workstations and enable
the exchange of information between them,
Inputs from the various monitored items of equipment would be fed
to Local Scanner and Control Units (LSCU), which would contain a
microprocessor and be effectively a microcomputer. The LSCU is part of
a local control loop which can function independently, if necessary. The
LSCUs are connected up to a central computer which can interface with
them and would act as the workstation for the particular system.
Integrating the various systems enables optimal control of a ship and
improved efficiency. Fuel consumption figures could be monitored, for
example and used to predict an appropriate time to drydock the vessel
as hull resistance increased due to fouling. Condition monitoring of
machinery would enable maintenance schedules to be planned in order
to minimise breakdowns and repair costs. Satellite communications will
also enable data to be relayed from ship to shore for analysis by
office-based technical staff.