Exploring the Dimensions of Digital Twins: Types, Abstraction Levels, and System Interactions

A generic term for endless applications: what is a digital twin?

A digital twin is a virtual representation or replica of a physical object, process, system, or environment. It mirrors the characteristics, behavior, and performance of its real-world counterpart, often in real-time.

Digital twins are created using data from sensors, simulations, and historical records, allowing them to accurately reflect the current state, predict future outcomes, and optimize operations.

Key components of a digital twin

Typically, digital twins, regardless of their scope and type, are characterized by up to 5 elements

Tap the elements to see their definition.

1. A PHYSICAL ENTITY

The object being replicated

The real-world object, system, or process that the digital twin represents. This could be anything from a simple machine or product to an entire factory, city, or even a biological organism.

2. A VIRTUAL MODEL

The digital replica of the physical entity

This model is created using data and can range from a basic 3D representation to a highly detailed simulation that replicates the entity's behavior under various conditions.

3. A DATA CONNECTION

The data flow

Sensors and other data collection methods continuously feed the digital twin with real-time data from the physical entity. This connection allows the digital twin to update and reflect changes as they happen in the real world.

4. ANALYTICS AND ALGORITHMS

The problem solving engine

The digital twin often uses analytics, heuristics, machine learning, and AI algorithms to interpret the data it receives and create viable forecasts. These tools help predict future behavior, optimize performance, and identify potential issues before they occur.

5. INTERACTIONS

The ability to influence the real world

Digital twins can interact with their physical counterparts and other digital systems, providing insights, recommendations, or even automated actions based on the data they process.

1. A PHYSICAL ENTITY

The object being replicated

The real-world object, system, or process that the digital twin represents. This could be anything from a simple machine or product to an entire factory, city, or even a biological organism.

2. A VIRTUAL MODEL

The digital replica of the physical entity

This model is created using data and can range from a basic 3D representation to a highly detailed simulation that replicates the entity's behavior under various conditions.

3. A DATA CONNECTION

The data flow

Sensors and other data collection methods continuously feed the digital twin with real-time data from the physical entity. This connection allows the digital twin to update and reflect changes as they happen in the real world.

4. ANALYTICS AND ALGORITHMS

The problem solving engine

The digital twin often uses analytics, heuristics, machine learning, and AI algorithms to interpret the data it receives and create viable forecasts. These tools help predict future behavior, optimize performance, and identify potential issues before they occur.

5. INTERACTIONS

The ability to influence the real world

Digital twins can interact with their physical counterparts and other digital systems, providing insights, recommendations, or even automated actions based on the data they process.

As we will see in the following deep dive articles, in some cases, some “light” versions of digital twins can be described with a subset of these 5 elements.

However, among these, three of the elements in the cookbook are mandatory: a physical entity, a virtual model, analytics and algorithms. As an example, take into account a simulative digital twin for what-if analysis, specifically created to optimize the design of a new manufacturing plant or a process: as the physical entity does not exist yet in the real world, they are offline digital twins that cannot have data connection due to lack of data, do not apply interactions as there is nothing to interact with, and therefore are only marked by a physical entity, a virtual model, and algorithms. Nonetheless, they represent a replica of the physical object , as it mirrors the characteristics, behavior and performance of the entity (even though it is not existing yet).

As the adoption of digital twins grows across industries to achieve new competitive advantages, understanding their different facets becomes crucial for leveraging their full potential.

Even though the definition of a digital twin is pretty accurate, a digital twin is still a very loose concept and broadly defined in terms of type, scope, and areas of applications, as it could litterally constitute the replica of any entity of the real world. Even for the same physical entity, a digital twin could be designed and implemented in different ways in order to answer different questions.

This introductive article serves as a gateway to three in-depth explorations that will guide you through the essential dimensions of digital twins to understand its vast real: their types and characteristics, levels of abstraction, and interactions with other systems.

By exploring these aspects, you can gain a deeper understanding of the vast scope, diverse applications, and robust capabilities of digital twins, illustrated through real-world examples.

1. Types and Characteristics of Digital Twins

In the first deep dive, we explore the various types of digital twins, from simulative to prescriptive, each offering unique capabilities and benefits. This section breaks down how digital twins are categorized based on their core functionalities:

  • Simulative Digital Twins: Used primarily for virtual testing and experimentation before physical implementation, such category is actually a “light” digital twin, as it is missing a data connection and the interaction elements, as the object does not exist yet in the real world. Typically, a simulative digital twin is more rapidly deployed and more flexible than other types of strong data connection and interaction, due to their testing nature and scope, and lack of heavy system integration effort. Nontheless, based on certain algorithms, they can be particularly relevant in understanding the physical object, in sizing it (i.e. what is the correct size of each productive asset to remove bottlenecks?), and in defining and optimizin its behavior (i.e. how does a robotic arm or crane should move? What is the optimized way to manage it?).
  • Monitoring Digital Twins: Focused on real-time data collection and analysis to mirror the current state of a physical entity or process, such digital twin type is not forward looking and does not predict anything about the future state of the object, as it merely report the current status based on the available data via a centralized single point of access to informations. Anyhow, the monitoring digital twin is the basis for both the predictive and prescriptive digital twins as they both rely on current states to start predictions.
  • Predictive Digital Twins: Predictive Digital Twins leverage historical and real-time data to forecast future states, enabling proactive decision-making. By applying machine learning and AI to defined rules and historical performance data, these twins focus on anticipating potential future scenarios. They often include decision-making tools that allow users to analyze the impact of various actions on key performance indicators (KPIs). This capability makes predictive digital twins inherently exploratory, supporting quantitative “what-if” analyses that drive faster and more effective decision-making. They are particularly valuable in scenarios where understanding the potential outcomes of decisions is critical to optimizing performance.
  • Prescriptive Digital Twins: Going a step further, this type of digital twin is an evolution of the predictive digital twin. While the former rely on static logics, defined by the business mostly as “common sense decisions or rule of thumbs”, in the latter, an artificial intelligence, typically a reinforcement learning agent, is applying optimized dynamic decisions over time by himself. If properly configured and trained, this solution can provide outstanding results, unmatcheable with any other methods.

For each type, we will discuss its applications across different domains—such as product design, manufacturing, and urban planning—illustrating the value they add. By comparing these types, this section will help you identify which digital twin best suits your specific needs.

2. Levels of Abstraction in Digital Twins

The second article delves into the levels of abstraction at which digital twins can operate. Digital twins are not one-size-fits-all; their scope can vary significantly depending on the scale of application. For example, in a manufacturing enterprise 4 levels typically exist:

  • Workstation-Level Twins: Focus on individual machines or workstations, providing detailed insights into localized operations.
  • Process-Level Twins: Represent an entire production line or process, optimizing the flow and efficiency of specific operations.
  • Site-Level Twins: Encompass a whole manufacturing site, integrating multiple processes and systems into a cohesive digital representation.
  • Supply Chain-Level Twins: Extend the scope further to cover the entire supply chain, enabling end-to-end visibility and optimization.
This section will guide you through how digital twins can be tailored to different levels of abstraction, helping you in understanding the differences in terms of requirements, inputs, outputs and KPIs to succeed in any digital twin implementation project.

3. System interaction

The final deep dive focuses on the interaction of digital twins with other systems. A digital twin’s true power lies in its ability to integrate with and influence other digital and physical systems:

  • Standalone Simulations: Operate independently, providing insights based on isolated models.
  • Digital Shadows: Offer a one-way flow of data from the physical to the digital, useful for monitoring and analysis.
  • Interconnected Digital Twins: Enable a bi-directional exchange of data and insights, allowing for dynamic interaction between the digital twin and the physical world.
This section explores the various levels of system interaction, highlighting pros and cons of each level of system interaction and describing how interconnected digital twins can drive significant innovation and continuous optimization by creating an autonomous feedback loop between the physical and digital realms.

01

DIGITAL TWIN TYPES AND CHARACTERISTICS

In-Depth exploration of Digital Twin Types:  characteristics, technologies, and value added by area of application

02

DIGITAL TWIN ABSTRACTION LEVEL

Understand what is the abstraction level – from broad E2E digital twins to detailed object level digital twin – inputs, outputs and key questions answered

03

dIGITAL TWIN AND SYSTEM INTEGRATION

From standalone simulations to closed-loop digital twins interacting with corporate IT systems: pros, cons and challanges from proof of concept to enterprise scalability

04

dIGITAL TWIN STANDARDS

Standard vs. Custom Digital Twins: Navigating Complexity in Modern Systems