The Power Of Digital Twins and Digital Threads
“Digital Twins” and “Digital Threads” are recent terms, but the concepts they represent should be familiar. A digital twin is a virtual representation of a physical product, much like a simulation or digital mockup (DMU). A digital thread, on the other hand, is a product lifecycle management tool.
The difference is that digital twins and digital threads address the additional needs created by interconnected devices and applications.
What Is A Digital Twin?
The difference between a Digital Twin and a conventional simulation can be illustrated by the example of an automobile.
Before 1968, cars were a collection of physical parts that could be adequately represented by a conventional simulation. However, in 1968, Volkswagen released the Type III. The Type III had a pressure sensor that fed data to a circuit board. That circuit board used the data from the sensor, in conjunction with the engine speed, to control the fuel injection rate.
This is widely considered the first computerized automobile system. And while the conventional simulation was well suited to describe the Type III’s physical parts, it couldn’t describe the data from the pressure sensor, the engine speed, the fuel injection rate, or how the circuit board mediated it all.
Today’s connected devices pose even greater complications. Not only is there sensor data to consider, but also continuous connectivity, embedded software, real-time data communication and analysis, and so forth.
To wit, one doesn’t simply need a representation of the physical product; one must also represent the data associated with the product—data, which are constantly in flux.
And this is where the digital twin comes into its own.
Conventional simulations are static. A digital twin is instance-based. That means it provides a snapshot of the product at a given moment in time, incorporating the relevant sensor data, contextual information, business data, and so forth for that moment.
One could also view a digital twin as a DMU in real-time.
The purpose of a digital mockup is to fully test a proof of concept for a product before that product goes into production. A digital twin looks at real instances of products in use, and those products’ associated data.
If a product in the field has a digital twin, it can report information to its twin regarding real-life conditions, such as the product’s status, any ambient environmental factors, and more. It’s not just a virtual representation of a physical object; it’s a current and exact representation that adds context to the time-series data streaming back from the field.
Digital Twins And PLE
Product line engineering is an efficient way to engineer – to plan, produce, deliver, deploy, sustain, and retire – a group of related products. By looking at the products as a group, organizations can optimize engineering by focusing on the products’ similarities while managing their differences.
So, what does that have to do with digital twins?
Products in a product line not only have individual features; they also have variations on those features. In addition, those features interact with one another. This can generate a daunting amount of information for specific products, and the group of products.
A digital twin keeps track of all this information for each product in a product line. In addition, it makes it possible to understand the impact of changes in features and variations of features in a connected way.
As Charles Krueger, CEO of Big Lever Software explained to Design News, the idea of a “feature,” for example a blind spot alert system in an automobile, means something different to people involved in the different parts of production. The mechanical team would think of this feature in terms of parts. The electrical team might consider it from the point of view of algorithms. And the marketing team would think about this feature, or any other, in terms of selling points.
A digital twin provides all this information in one place. What’s more, all these people can access this information across the stages of production.
This brings us to the concept of digital threads.
What Are Digital Threads?
While a digital twin provides an in-the-moment snapshot, a digital thread provides ongoing monitoring of a product throughout its entire lifecycle. It’s product lifecycle management not only of the physical product but of all its associated data and processes.
According to Krueger, digital threads allow manufacturers to continue their relationship with products once they’ve been sold and deployed in the real world. This, in turn, allows the manufacturer to know how products are performing in real-time, and to even detect malfunctions that are happening or about to happen.
What Does This Mean For PLM?
IoT applications present additional challenges for product lifecycle management. Conventional PLM implementations were meant for mechanical design. They were never meant for mechatronics, and when it comes to managing data for mechatronics, conventional PLM isn’t a perfect fit.
In addition, different fields have different PLM systems. There’s PDM (product design management) for mechanical design, application lifecycle management (ALM) for software design, electronic design automation (EDA) for electronics, and so forth.
These systems, which have been in use since the 1990s, have evolved through a process of bolt-ons, rather than being reworked from the ground up to keep up with the evolution of manufacturing. This means that in addition to being field specific, they’re complicated to upgrade.
When it comes to mechatronics, there’s also the problem of integrating mechanical, electronic, and software systems and their data.
According to Marc Lind, senior vice president of strategy for Aras Corp, a digital thread connects the various tools used for developing mechanical, electrical, and software components to create a single cross-discipline data environment to support mechatronics.
This, in turn, allows an organization to trace every decision made throughout the complete product lifecycle and connect the data back to the information that the digital twin provides.
The Power Of Digital Twins And Digital Threads
Digital twins and digital threads are familiar data management concepts updated for the world of connected products. They are agile, dynamic, and transparent. More importantly, they can provide both in-the-moment and across-the-lifecycle information to all parties involved in the product, from design to implementation to retirement.