Digital Twin Development for Serial Manipulators: Data Driven Optimized Planning and Sequencing of Tasks
conference paper by Huynh et al. 19 The real-
time cobot joint data from the cobot asset
are streamed to the cobot DT model for live
monitoring and synchronized cobot
movements.
the shaft assembly station. Next, the
engineer examines the actual cobot with a
new path as a final test and releases for shaft
sub-assembly productions. That will trigger
the warehouse system to start delivering the
necessary parts to the shaft assembly station
by an AGV. Subsequently, the shaft assembly
station operator starts the customized work
order at MES, and the cobot assembles the
sub-assemblies accordingly. The completed
products are moved to the warehouse by the
AGV and the smart inventory system informs
ERP for the order completion.
The robotic engineer starts working on
creating the new cobot motion path virtually
once he is notified about the customized
work order from the manager. This process
will not interrupt any operations on the on-
going production line. There can be many
iterations and validation processes carried
out for developed simulation models, and
the virtual cobot is useful for reviewing the
new cobot path planning. As for the
preparation of the customized work order,
the deep learning model of assembly parts
recognition is trained with computer vision
techniques at the same time. Later, the
trained part recognition model will be tested
and integrated with the new motion plan for
picking, placing and assembling accordingly
for the shaft assembly process. The result of
motion planning software is transferred to
the cobot DT model (virtual cobot) for
verification of correct cobot paths by the
engineer. This is where the data is
transformed into information used for
effective
decision-making.
After
confirmation, the motion plan is released
through the information gateway to the
robot controller.
In this use case, the communication and
information flow between the associated
assets on the shop floor are critical to realize
the digital twin technology. With those
capabilities, the monitoring and control of
the production process and accessing
enterprise information are possible for the
production manager to make decisions in
the MICR. Apprehending the resource
requirements and planning necessary tasks
are the initial steps taken by the manager to
complete a customized order on time.
Hence, once the cobot at the shaft assembly
station is ready to perform the customized
work order, this state triggers to allow that
order to start in MES. That order is scheduled
to proceed next at the assembly line in the
MES interface as soon as the on-going work
order is finished. The vertical integration of
process, asset data and enterprise
information at the IoT platform enables this
operation. Once that work order is started,
the appropriate raw materials are collected
Only after the verification of the new cobot
path is completed in the virtual world, the
final motion path is laid out into the robot
controller which connects with a cobot at
19
Huynh, B. H., Akhtar, H., & Myo, K. S. (2019). A Universal Methodology to Create Digital Twins for Serial and Parallel
Manipulators, 2019 IEEE International Conference on Systems, Man, and Cybernetics, IEEE, Accepted.
IIC Journal of Innovation
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