[Paper Review] Revisiting Digital Twins: Origins, Fundamentals and Practices

Jiehan Zhou, Shouhua Zhang+1 more|arXiv (Cornell University)|Mar 24, 2022

Digital Transformation in Industry4 citations

TL;DR

This paper redefines Digital Twins (DT) as an advanced modeling and simulation environment integrating modern Information and Communication Technologies (ICTs) and engineering mechanisms, emphasizing lifecycle management, real-time sensing, geometric visualization, and predictive simulation. It traces DT's origins to established engineering practices like Virtual Manufacturing and Building Information Modeling, proposing a three-element model to clarify its fundamentals and correct widespread misuse in industry and academia.

ABSTRACT

The Digital Twins (DT) has quickly become a hot topic since it was proposed. It not only appears in all kinds of commercial propaganda, but also is widely quoted by academic circles. However, there are misstatements and misuse of the term DT in business and academy. This paper revisits Digital Twins and defines it to be a more advanced system/product/service modelling and simulation environment that combines the most modern Information Communication Technology (ICTs) and engineering mechanisms digitization, and characterized by system/product/service life cycle management, physically geometric visualization, real-time sensing and measurement of system operating conditions, predictability of system performance/safety/lifespan, complete engineering mechanisms-based simulations. The idea of Digital Twins originates from modelling and simulation practices of engineering informatization, including Virtual Manufacturing (VM), Model Predictive Control (MPC), and Building Information Model (BIM). Based on the two-element VM model, we propose a three-element model to represent Digital Twins. Digital Twins does not have its own unique technical characteristics; the existing practices of Digital Twins are extensions of the engineering informatization embracing modern ICTs. These insights clarify the origin of Digital Twins and its technical essentials.

Motivation & Objective

• To clarify the confusion and misuse of the term 'Digital Twin' in both academic and commercial contexts.
• To trace the historical and technical roots of Digital Twins to established engineering practices such as Virtual Manufacturing and Building Information Modeling.
• To propose a three-element model that better represents the fundamental components of a Digital Twin beyond the traditional two-element model.
• To define Digital Twins as an evolution of engineering informatization enhanced by modern ICTs, rather than a novel standalone technology.
• To establish a clear, technically grounded definition of Digital Twins that supports consistent application and research.

Proposed method

• The paper conducts a comprehensive review of existing literature and industrial applications to identify recurring misconceptions about Digital Twins.
• It traces the conceptual lineage of Digital Twins to foundational engineering practices, including Virtual Manufacturing (VM), Model Predictive Control (MPC), and Building Information Modeling (BIM).
• The authors propose a three-element model for Digital Twins, extending the conventional two-element model (physical system and digital replica) by incorporating a dynamic feedback loop involving real-time data and simulation.
• The study uses system-level analysis to demonstrate that Digital Twins do not possess unique technical characteristics but are instead extensions of existing engineering informatization frameworks enhanced with modern ICTs.
• It applies a comparative analysis between traditional engineering simulation systems and modern Digital Twin implementations to highlight continuity and evolution.
• The paper uses a conceptual framework to integrate lifecycle management, real-time sensing, and predictive simulation as core attributes of a true Digital Twin.

Experimental results

Research questions

• RQ1 What are the true technical and historical origins of Digital Twins?
• RQ2 Why has the term 'Digital Twin' been misused in both academic and commercial domains?
• RQ3 How does the Digital Twin differ from existing engineering simulation and modeling practices?
• RQ4 What core components define a genuine Digital Twin, and how can they be formally structured?
• RQ5 To what extent are modern Digital Twin implementations merely extensions of established engineering informatization with enhanced ICT integration?

Key findings

• Digital Twins are not a new technology but an evolution of engineering informatization practices such as Virtual Manufacturing, Model Predictive Control, and Building Information Modeling.
• The term 'Digital Twin' is frequently misapplied to any digital model or simulation, leading to confusion in both research and industry.
• The proposed three-element model—physical system, digital twin, and real-time feedback loop—provides a more accurate and comprehensive representation than the traditional two-element model.
• Digital Twins are characterized by system lifecycle management, real-time sensing, geometric visualization, and complete simulation based on engineering mechanisms.
• The integration of modern ICTs into existing engineering frameworks enables the capabilities attributed to Digital Twins, but these are not unique to DTs.
• The paper concludes that Digital Twins are best understood as advanced simulation environments that extend established practices rather than standalone innovations.