Showing results for 
Search instead for 
Did you mean: 

The Digital Thread


Industry Analyst Chad Jackson of Lifecycle Insights © LC Insights LLC is a guest blogger. The concepts, ideas and positions of this post have been developed independently.

Over the past few decades, product development and design data management has undergone a range of dramatic changes. Design has gone global as technical centers have proliferated around the world. Schedules have become more and more compressed. Products, with the explosion of electronics, software and internet connectivity, have become exponentially complex. Supply chains have become deeper, more diverse and specialized.

One change, however, has occurred inside manufacturers: the digitization of operations. You see, almost every aspect of any process or documentation of a company gone digital. Emails are now the primary means of communication. Issues and processes are enabled with digital documents. Fundamentally, almost every aspect of operations within a company has changed.

What about product development? Well, it is no exception. It has also become completely digitized. Yet, its transformation carries some significant implications that every company needs to understand. That’s what we’ll cover in this post.

The Digital Twin

The digitization journey for product development started way back when mechanical engineers first started creating electronic 2D drawings. Over time, of course, engineering converted to richer embodiment of the design as 3D models, a physically accurate digital representation. This then broadened to include more and more of the design’s traits and characteristics, including physical performance in the form of simulation. Today, as companies journey continue in the form of Model-Based Enterprise where other functional departments such as manufacturing, service and others use engineering’s 3D model to create their own representations such as manufacturing models to produce NC toolpaths and service models to create maintenance instructions.

This path has been mirrored in other engineering disciplines. Electronics engineers can model their printed circuit boards, systems-on-chips and wiring harnesses to similar degrees. Software engineers have evolved to Model Based Development which simulates code running against a model that mimics the reactions of the physical world. System engineers develop 0D and 1D definitions of their designs and then simulate their performance. Even as product complexity has risen, the digitization of the definition of the product has kept pace.

In combination, these digital representations of a product’s mechanical, electrical, software and systems aspects can be considered a Digital Twin. This comprehensive digital representation of the product not only offers definition, but simulates its performance and operation. The digitization of the product is relatively complete.

As a side note, it is interesting that the digital representation is often called the twin of the physical one. Maybe it’s me, but this strikes me funny as the digital aspect is created first and then used to create the physical one. Given that, shouldn’t the physical manifestation be called the twin? We’re merely talking semantics here. But it’s an interesting thought nonetheless.

The Digital Thread

Now, another fascinating aspect of the Digital Twin is that it is is almost never static. That is, it is always changing. In the work in process phase of design, it changes very rapidly, perhaps hundreds of times a day. But even after design release, the Digital Twin still evolves, albeit more slowly, as the change process takes over. It is often improved over time.

Given good configuration management practices, which should be in place at practically any manufacturer of products of any size, an interesting concept emerges. The Digital Twin, with its changes, leaves a historical trail of its definition as time passes. This is called the Digital Thread. To be clear, this Digital Thread is actually composed of many smaller threads woven together. There are ones for each system and subsystem. There are ones for each hardware assembly, subassembly and component. There are ones for each software binary. Each has a historical trail for its Digital Twin.

This concept becomes incredibly powerful when the need arises to revisit the Digital Twin at one point in time. Looking at one slice of the Digital Thread equates to states of all of the Digital Twins of each aspect, systems, mechanical, electrical and software, of the product at the same time. This provides the ability to view and inspect the digital representation of the product, in its entirety, at that point in time.

Why would anyone want to do this? There are many reasons. For regulatory reasons, a company might be legally required to disclose the due diligence, as represented by simulations and other documentation, completed on a certain date. In consideration of a change request, a team of engineers might need to review the product immediately after a prototype test to identify the root cause of a failure at a later date. The Digital Thread becomes a powerful asset to use throughout the rest of the product’s lifecycle.

Interestingly, we are now entering a era where the Digital Twin and Digital Thread can be extended further. With the ability to connect to products in the field and collect operating data from sensors, the Digital Twin can now represent how a product is running after it has been delivered. Tracking performance over time extends the length of the Digital Thread beyond design release and even product launch. Quite literally, the Digital Thread could be the historical trail of the entire product’s lifecycle, from concept all the way through disassembly.

PLM is a Critical Enabler

Many technologies are needed to make the Digital Twin and Digital Thread a reality. CAD and CAE tools are needed to design and simulate the performance of hardware. Software development tools are needed to develop the code. Systems modeling and simulation tools are needed for those aspects of the product. IoT technologies are needed to capture operational data. All of these tools aid in creating a more complete Digital Twin.

The other aspect of this IT ecosystem, however, are the systems that track, manage and control these representations and data. PLM and ALM systems are required to create the historical trail of the changing Digital Twin. In essence, these systems create the Digital Thread.


  • The Digital Twin is a rich and increasingly complete digital representation of the product. The initial steps to creating it started long ago with 2D CAD. But today it is still evolving with 3D CAD and CAE, software development tools and IoT-based technologies.
  • The Digital Thread is the historical trail of the Digital Twin. IT systems such as PLM, ALM and other IoT data capture systems track, manage and control the models and data that makes up the Digital Thread.
  • With the advent of the IoT era, data captured from operating products enables the Digital Twin to represent the current product. Over time, capturing this data allows the Digital Thread to be extended far past design release or even product delivery. Ultimately, the Digital Thread could track the history of the Digital Twin from concept all the way to disassembly, spanning the entire lifecycle.

Model Based Definition and Model Based Enterprise initiatives are a big part of the Digital Twin. To learn more about it and how it fits into the Digital Thread, read Lifecycle Insights’ new eBook titled CAD and PLM Crucial to MBD Initiatives. Take care. Talk soon.

The eBook is licensed for hosting by Siemens PLM. The concepts, ideas and positions of the blog post and eBook have been developed independently by Industry Analyst Chad Jackson of Lifecycle Insights © LC Insights LLC