1. Introduction: Architecture of a DT Flashcards
What is a DT
A virtual replica of a physical system that represents a selected set of its behaviors and reflects changes in the physical system.”
‘Selected set’
Not all behavior must be included. E.g. for energy management purposes of a car, its color is not relevant.
‘Reflects changes’
If a bearing fails, it should also ‘fail’ in the digital twin. This implies an exchange of information
‘Twin’ is the essential word in Digital Twin, not ‘Digital’
DT IN A SYSTEM LIFECYCLE
What is system life cycle of a DT.
Digital Twin concept originates from Product Lifecycle Management (PLM)
DTP–>DTI–>DTA.
DTP allows to virtually optimize, test and predict the system’s behavior before it exists
DTI: Individual products that are made.
DTA: All products that have been made
Digital model - digital Shadow and Twin
DATA/INFO EXCHANGE
Differences between DM - DS - DT
What is DM and what are the characteristics
- **Virtual representation of a physical system able to accurately represent a predefined set of behaviours of its physical counterpart.
* No automated exchange of information between the physical system and its digital model, i.e., any information is transferred manually. -
Does not necessarily have to model all possible behaviours of the physical system, nor are there any restrictions on the required computational effort or real-time computation.
*
Digital models are omnipresent in all engineering disciplines and are used in the design phase of a machine for, e.g., virtual controller tuning, virtual commissioning or structural load analysis.
What is Model Fidelity
How realistic the behaviours of the model van be repdroduce
When does a DM changes to DS(shadow)
digital model is upgraded into a digital shadow by adding a unidirectional automated data or information flow from the physical to the virtual system, while a digital twin requires the data flow to be bidirectional.
What is a DT, definitions and characteristics
- A virtual replica of a physical system that represents a selected
set of its behaviors and reflects changes in the physical system.” - ‘Selected set’ Not all behavior must be included
- Reflects changes’: This implies an exchange of information.
- IT DOSEN’T REQUIRES A REAL TIME COMPUTATION. Although this does not strictly require real-time computation, the virtual state of the digital twin preferably coincides with the state of the physical system on a regular predefined time interval to be of use in practice.
THE PHYSICAL AND VIRTUAL SYSTEM
Differences between PS and VS
THE PHYSICAL AND VIRTUAL SYSTEM
What is a Cyber Physical Systems
DT vs CPS
How do we distinguish between CPS and DT?
̶ Cyber-part is essential in the operation of the CPS
̶ Without the cyber-part, CPS cannot operate
̶ DT can enhance performance of physical system
̶ But without the DT, physical system should remain
operational, possibly with reduced performance
If DT is essential in the PS’s operation, consider it as part of the CPS (not separate as a DT)
Digital Twin building blocks
What are the DTBb?
What could be the “Physical asset”
In this course we will mainly focus on mechatronic systems, which typically constitute
* A single asset
* A combination of mechanical components with sensors and
actuators..Mechatronics
* Which need to deliver high
performance
* Sensors and actuators
IT infrastructure
Kind of IT infrastructure:
Cloud-based Digital Twins
* Enables combining information from multiple assets
* Various access points possible (application nodes)
* Possibility of heavy computations on the cloud system
* Access to a broad range of applications
* Often complicated architectures which are
mainly suitable for high-value assets
* Various commercial offerings
Kind of IT infrastructure:
Edge-based Digital Twins
* From simple prototype boards to high-end real-time prototyping systems
Does the Digital Assets and its peripherals can live on the (embedded) edge or on the cloud, or combined. Examples
Examples of Communication layer?
LAN - CAN - WIFI
Considerations of the communication layer
How does the VIRTUAL ASSETS can be represented
Simulation Models: Most important; simulations (physics and data driven).
What are they key challenges of a virtual assest?
Key challenge how to optimally leverage both measurement data and models
What is the rol of the application layer and what does it does.
The application layer (AL) queries the Digital Twin, and convert this into actionable information.
“The application layer should typically be your starting point!”
DATA IN DIGITAL TWINS
What are the dimensions of the DT
DM–>DS–>DT
How is the data path?
What are data objects and attributes?
An attribute is a property or characteristic of an object
* A collection of attributes describe an object
