What is a digital shadow and why do we need it to reach the digital twin? Dr Melanie Robinson, senior digital consultant at BIM Academy, casts light on the topic.
Asset and estate owners are increasingly having to deal with maintaining two asset types. The first is the physical asset, as they always have done. And now is the digital asset, insofar as to ensure the digital information is always reflective (or rather, a reliable interpretation) of the physical information, whether geometric, non-geometric, or documentation.
The idea of this physical-digital synergy is why the term “digital twin” has gained so much traction and is even creeping into client aspirations. However, to me, the concept of a digital twin implies a symbiotic relationship, not just a synergy.
Where a digital model developed using BIM processes can certainly act as a prototype for the physical asset, digital twins start to introduce the user to applications such as simulation, prediction and even control. The digital twin therefore strives to extend beyond a repository and become an active agent in an owner’s decision-making process.
There is a catch: a lot of asset and estate owners – and much of industry – do not have the capability to achieve this yet, both from a people and process perspective, and arguably from a technology perspective too.
“A digital shadow strives to overcome the as-built/as-maintained gap we create when we hand over the project information model.”
However, we appear to be missing a step within the information management using BIM workflow, which would form the foundation on which to build a digital twin solution: developing and maintaining a “digital shadow”.
Introducing the digital shadow
Without wanting to throw yet another term into the ocean of lexigraphy, buzzwords and acronyms we seem to have created for ourselves, a digital shadow is borrowed from academic work and other sectors, such as manufacturing and healthcare. It might not even be the right term or have the right connotations for our industry, but what it does do is push and remind us of the concept entrenched in ISO 19650-3.
A digital shadow strives to overcome the as-built/as-maintained gap we create when we hand over the project information model by maintaining the asset information model in line with physical asset. Otherwise, the model just remains “static”, “as-is”, “as-built”, whatever you want to call it. It might as well be a paper model or manual on a dusty shelf!
This is the crux of the issue for owners, particularly large estate owners: whether drawn by hand or parametrically modelled, information quickly becomes unreliable and unreflective of reality if processes are not in place to maintain it.
The perceived roadblock to maintaining digital asset information is the capability and capacity of owners and operators to interact with and manipulate the object-based environment themselves. As we’ve seen with BIM, software and upskilling can hinder adoption by being seen as a large capital expenditure with only anecdotal evidence to rely on to demonstrate a sound return on investment. In other words, there is a real dearth of hard evidence on which to build a business case.
What does the asset owner want?
However, as with the wider information management rhetoric, it fundamentally boils down to why the owner wants information and the processes we can put in place to support their objectives and information purposes.
“Asset owners want a digital shadow that is built on clear information requirements and good information management.”
Even if the owner decided never to touch the federated model again, they would still want relevant information within their O&M manual. And, of course, up-to-date drawings so they can run their assets effectively. They would still want this information to be provided in a way in which it is searchable, accurate and valid, and can interact with their existing systems. They would still want a digital shadow that is built on clear information requirements and good information management.
These principles form the foundation to any digital transformation journey: realising more intelligent applications, such as prediction and simulation, simply builds on these initial steps by employing innovative technology, such as artificial intelligence.
So, while we as an industry get to grips with what a true, symbiotic digital twin looks like, owners and operators need to start thinking about what they truly want out of their digital information and understanding how structured data can inform these decisions. Is it the ability to predict building behaviours, or is it simply a case of calling up reliable, current information when required?
Either way, to truly embrace the benefits technology is bringing to the built environment, we need to first support owners in leveraging their own digital shadows.
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