Digital Twin in Industrial Application – Requirements to a Comprehensive Data Model
requirements in terms of material, compo-
nent and condition monitoring are ex-
tremely high. A carriage breakdown causes
major difficulties. Furthermore, the with-
drawal of a train from service has serious
timetabling implications since replacing it
may take hours. During operation, the repair
options for trains are limited as the railway
depot is often the only site where proper
maintenance and repair can be performed.
Based on this use case, the most critical IIoT
requirements are to:
Carriage doors, in particular, are a crucial
component of a train. Any door failure can
extend the stopping time in stations and
cause delays. Furthermore, the safety buffer
for evacuating trains in the event of an emer-
gency is reduced if an exit is blocked; and if
there are too many such exits, the train may
not be allowed to operate at all. At the same
time, doors are sensitive to contamination,
and, as regular moving parts, mechanical
and drive elements suffer from high levels of
wear.
C ONTENT OF A D IGITAL T WIN D ATA
M ODEL
Regarding the requirements placed on digi-
tal twin data models, we need to start from
a general view. In the survey mentioned
prior (“Smart Industrial Products”), the three
most important elements of a digital twin
identified by the industry experts were: 1)
the software version installed on the asset,
2) the asset configuration in terms of prod-
uct-specific parameters and 3) the unique ID
of the asset. Additional requirements just
slightly outside of the top three were 4)
views of components from the perspective
of different disciplines, 5) related documen-
tation and audit information and 6) 3D visu-
alization (see Figure 3).
As trains have a long product lifecycle, the
replacement of parts and the refurbishment
of subsystems or even complete carriages is
a regular activity. In many cases, such modi-
fications to trains, regarded as a system in
themselves, may influence the behavior of
the doors. To predict their functionality or
the risk of breakdowns based on sensor
data, it is therefore necessary to possess an
overall up-to-date as-maintained-state of
the carriage.
IIC Journal of Innovation
Consolidate key measures of system
behavior
Consider environmental influences
Describe the as-maintained-state in
terms of the actual components in-
stalled, including third party spare
parts
Describe the interaction with sur-
rounding components of the overall
system
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