One of the main differences, in my opinion, is in the feedback applied.
For example, if you have a 6DOF model of a collaborative robot arm, you could simulate different movements of the robot on its 3D model. The model of the arm would look and move exactly like the real-world arm. That would be a classic simulation model.
However, if the real-world robot arm would be, at some point, stopped and moved by the human to the new position and that movement would be detected by the encoders (sensors) and reflected in real-time in the 3D model via encoders’ feedback, that would be a primary novel characteristic of “Digital Twin”, which classical models do not include.
Besides, if one stops the arm in the simulation model (metaverse (VR)) and moves it to another position, that should be reflected in the real-world robot arm in real-time. This is also not included in classical models.
“Digital Twin” might therefore be understood as a simulation model connected to a real-world object, which incorporates the feedback from the sensors to reflect the interactions in real-time between:
- the environment (human or some other intervention) and real-world objects (robot arm)
- simulation model (metaverse (VR)) and real-world objects (robot arm)
Thus, digital twin should enable two-way, real-time interaction.
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My question
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explain modelling, simulation and digital twins with references
ChatGPT
Modelling, simulation, and digital twins are all concepts related to representing and understanding real-world systems in a virtual environment. While they share similarities, each term has its own distinct characteristics. Let's explore them in more detail:
Modelling: Modelling refers to the process of creating a simplified representation of a real-world system. It involves identifying the key components, relationships, and behaviors of the system and representing them using mathematical equations, algorithms, or other formal descriptions. Models can be used to gain insights, make predictions, and understand the behavior of complex systems.
For example, in engineering, a model of a bridge may be created to analyze its structural integrity under various conditions, such as different loads or environmental factors. Models can be physical (e.g., scale models) or conceptual (e.g., mathematical models) depending on the nature of the system being represented.
Simulation: Simulation involves running a model to observe the system's behavior or to predict its outcomes. It is the process of executing a model over time to understand how the system evolves and responds to different inputs or scenarios. Simulations are often used to test hypotheses, make informed decisions, optimize processes, or train individuals in a risk-free environment.
Simulations can be performed using computer programs or physical prototypes. They allow researchers, engineers, or decision-makers to observe and understand the behavior of complex systems without the need for costly or time-consuming real-world experiments.
Digital Twins: Digital twins are virtual representations of real-world objects, processes, or systems. They go beyond traditional models and simulations by integrating real-time data and feedback from the physical counterparts they represent. Digital twins aim to mirror the behavior, performance, and characteristics of the physical system as closely as possible. This allows for monitoring, analysis, and prediction of the physical system's behavior in real-time.
Digital twins are particularly prevalent in the Internet of Things (IoT) domain, where physical objects are connected and communicate data to their virtual counterparts. By linking the physical and digital realms, digital twins enable real-time monitoring, predictive maintenance, optimization, and decision-making.
References:
Grieves, M., & Vickers, J. (2017). Digital twin: mitigating unpredictable, undesirable emergent behavior in complex systems. In Procedia manufacturing (Vol. 7, pp. 13-18). Elsevier. Link
Robinson, S. N., & Srinivasan, R. (2019). Simulation modeling and analysis (5th ed.). McGraw-Hill Education.
Pärn, E. A., & Graubmann, T. (Eds.). (2021). Digital Twins: Concepts, Methods, and Applications in Engineering. CRC Press.
Tao, F., Cheng, J., Qi, Q., Zhang, M., Zhang, H., & Sui, F. (2018). Digital twin-driven product design, manufacturing and service with big data. The International Journal of Advanced Manufacturing Technology, 94(9-12), 3563-3576. Link