9 Actionable Data Sources (Applied Knowledge)
The last stage on the peak of the data sources model is the actionable data sources which includes the
applied knowledge. The applied knowledge contained in the data is actually applied to the system to
control the outcomes and for health and performance monitoring where it may be provided by a 3
rd
party
vendor. At this stage, the data quantity has been significantly decreased compared to the previous process.
9.1 Manual Systems Control
Manual system control requires that a human operator be involved in all controlling activities in order to
perform system functions. In these systems, the operator alone senses control data, makes control
decisions, and implements the control actions without support by mechanical or computerized equipment.
On contemporary offshore assets, very few control systems are purely manual. The most common
application of actionable data is in automated control, discussed in 2/9.5 below.
Onboard the vessel, the operator can view the automated control systems from diesel engine control to
power management system, from alarm and monitoring system to DP control system. Programmable Logic
Controller (PLC), Distributed Control System (DCS) and Supervisory Control and Data Acquisition
(SCADA) systems are commonly used in automatic control systems. The actionable data sources play key
roles in these automated systems. For example, a DP control system aggregates multiple actionable data
sources to implement the automatic control required in dynamic positioning operations.
9.3 Mechanized System Control
Mechanized system control commonly requires the support of computerized data. A large number of
mechanized control systems are in place on contemporary offshore assets.
Mechanized control systems are simply systems that incorporate mechanical and digital machines to
augment human strength, intelligence, and judgment in order to control equipment. Systems that require
mechanized support to enable control commonly provide a combination of mechanical, electric, hydraulic,
pneumatic, or computerized controllers. No matter the type of control augmentation, the human operator is
an essential “component” of the control system. In contrast, manual systems and their control depend
solely on the strength, knowledge, and judgment of an operator without the benefit of the augmentation
described above. Fully automated systems can operate without the presence of a human operator.
Mechanized control system architectures that include computerized controllers, commonly rely on digital
data in order to function. The integrity of digital data supporting computer-augmented mechanized control
systems for critical functions is to be protected.
9.5 Automated System Control
Automated system control is increasingly present on contemporary offshore assets. A significant number
of sophisticated drilling control systems have been placed in drilling platforms.
The automated control system uses control theory for regulation of processes without direct human
intervention. Such systems require the least human operator involvement. Without human operator
presence, automated systems and their control depend on sensors, transducers, transmitters, controllers and
final control elements. In the simplest type of an automatic closed loop control, a controller compares a
measured value of a process with a desired set value, and processes the resulting error signal to change the
input to the process, in such a way that the process stays at its set point despite disturbances.
Automated control systems rely heavily on timely and accurate digital data in order to function. The
integrity of digital data supporting software based on automated control for critical functions must be
protected if the system is to operate reliably and correctly.
Some examples of automated control systems onboard vessels include diesel engine control, power
management systems, alarm and monitoring systems, and DP control systems.
Section 2 Data Sources 2
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