When the Athenian hero Theseus had to find his way out of the Labyrinth after killing the Minotaur, he followed a thread his new girlfriend Ariadne had rolled out from a clue (or ball—sometimes spelled “clew”) of thread she carried. In English, the term has also come to mean a piece of evidence used to clear up a mystery.
While manufacturing isn’t as much of a mystery as the labyrinth, it does hold surprising complexity, and its path is not always straightforward. And so the Internet of Things provides the Digital Thread, an end-to-end informational link that allows manufacturers to understand and find their way through every part of the manufacturing process.
Why should engineers work in silos?
As with most complex procedures, manufacturing looks unified only from the outside. But no complex organization functions without specialized groups working on specific types of tasks. “Silos” are denigrated, but keeping boundaries between functional areas can be an effective way to focus resources and expertise. Nevertheless, all of these different areas must coordinate their efforts.
A manufactured product follows a complex path from initial concept to final maintenance in the field, through design engineering, production, and field operations and service. There has always been a gap between the engineering design side and the manufacturing production side. And field service people are different again. Each area has its own culture, educational requirements, rhythms, and assumptions. They often work fairly independently.
While it isn’t true that the design engineers just toss their design over the wall into manufacturing, who then go on their way without informing engineering of even significant changes, the relationship has not always been the smoothest. Field service sometimes feels that it understands the product as it functions better than anyone—but only by working around seemingly odd features designed and built into it.
These differences will not disappear because of the Digital Thread, but a common reference point for information will do a great deal to incent and enable cooperation and communication.
The foundation: the bill of materials (BOM)
In manufacturing, every operation or plan centers on one concept, the Bill of Materials, or BOM. The Digital Thread is, fundamentally, a way of keeping tabs on the BOM.
A BOM is a combination of a shopping list and a recipe for creating a product, including both the parts and subassemblies that make up the product, whether from a vendor or from the warehouse, along with work instructions for each step of assembly. BOMs are highly documented, and often stacks of paper follow a subassembly through the manufacturing process.
The Digital Thread’s effectiveness rests on the BOM. The Digital Thread allows for a comprehensive and systematic set of attributes that can remain consistent from the original CAD drawings, through the engineering drawing, parts specifications, warehouse and supply processes, and other engineering data, while also incorporating shop floor changes, quality inspection results, and beyond, the customer usage and field repairs.
Motivations for the Digital Thread
There are many purely manufacturing and commercial reasons for companies to adopt the Digital Thread, including:
• Being able to trace a CAD model through the manufacturing process to identify possible bottlenecks and inefficiencies before actually setting up on the shop floor
• Harvesting real-time product data via sensors and analyzing them to check how closely shop floor processes track the prediction
• Making the supply chain transparent to identify upstream delays or problems long before something is late at the loading dock so that adjustments can be made, while continuing to reduce inactive inventory
• Fully specifying each “as-built” product, with all of its customization and variants, so that a field service person knows exactly which part will be required
• Knowing the “as-maintained” product, as parts are replaced or adjusted over time, and tracking statistics on the failure rate of various parts, and tracing those back to specific manufacturing conditions
• Getting and incorporating customer usage data into the product redesign process, thus closing the loop back to design engineering
But other, perhaps less-obvious motivations exist for Digital Thread adoption, including:
• Meeting various security, sourcing, safety, and other mandated compliance requirements via the traceability that the Digital Thread provides.
• Enabling the already common move into providing products as services, with clients paying by the hour or other measurable performance endpoint rather than buying a product
• Demonstrating compliance with carbon emission or other sustainability metrics—and thus being able to use this compliance for marketing or favorable product placement
• Providing evidence in delivery or performance-based lawsuits
As in other IoT implementations, the non-engineering benefits of the Digital Thread may be undervalued by the technical people responsible for planning and execution—but informing Accounting, Legal, Marketing, Compliance, and HR of its benefits may gain unexpected advocates.
The Digital Thread can end up guiding the entire company through the manufacturing labyrinth.