Bentley’s AEC digital twin combines BIM, CAD and more
The Year in Infrastructure (YII) is Bentley Systems’ annual media fest, where new product releases, customer successes and acquisitions vie for attention. We’ll cover more of those over the next several blog posts, but today we’ll focus on one of the big product announcements, Bentley‘s iTwin Services, a set of technologies that make the digital twin accessible to AEC owners and operators.
First, what’s a digital twin? In simplest terms, a digital twin is a computer-based equivalent of a physical object. For the stapler on my desk, it’s a CAD assembly, a bill of materials (BOM), maybe assembly instructions. For an airplane, it’s CAD and BOMs, but also electronics, the setup and results of simulations and much more. And for hospital, it’s likely to be the building’s original drawings, schedules for the HVAC, plumbing and other systems, equipment installation manuals, maintenance histories, a sketch of the time the ambulance hit a pillar — info from many systems, a lot of which aren’t digital. Creating a twin of a stapler is easy; a lot harder for an airplane but probably doable, since so much of it is digital. For the hospital, it becomes a complicated exercise of finding and verifying paper, digitizing it and then updating that to match the current as-is state.
So why do this? Why create a digital twin? Because it’s the starting point for all sorts of potential opportunities. If you have accurate and current information about the plane or building, you can optimize its operation. Know an area of the building is unoccupied? Tweak the climate control to do the least needed for that space. Find that jet engine performance is decreasing? Schedule maintenance to fix it, but as part of daily routine and not in crisis mode. This combo of historic and current data helps operators predict and optimize performance and hunt for new revenue or savings opportunities.
Digital twins aren’t as much of a hot topic in the AEC world as they are in discrete manufacturing. In fact, CEO Greg Bentley said during his YII keynote that “you’ve heard not a thing from Bentley Systems about digital twins until now” because too much of the data needed to build them for AEC assets is missing or out of date. Most egregious is what Bentley calls “dark data”, meaning on paper or in a digital format or place that’s too hard to use. The first step with paper is to digitize it. Then it needs to be made more intelligent —perhaps by overlaying it onto a model created via laser scanning or photogrammetry— and, finally, combined with other forms of data to build out a comprehensive digital representation.
Enter the iModel 2.0 cloud platform and the iModelHub service that Bentley announced at last year’s YII,. These (and iModel.js, to be covered in a future blog post) make it more practical to use legacy data to create as-designed representations of AEC assets. Think of the iModel as a relational database that describes something—a CAD model, an Excel spreadsheet, a construction schedule—whose changes are synchronized and distributed by the iModelHub.
Let’s say you‘re renovating a school. You have a 3D CAD model of the building and a 2D drawing for the plumbing. You could eyeball whether the plumbing changes are going to work … not so good. You could spend time moving data from the 2D to the 3D as work progresses (which means everything is always at least one cycle too old) OR you can use iModels and the iModelHub to connect it all, in real time, and work with that composite. That gets you to the as-built state. Fast forward a couple of years; your as-built is now out of date. You can update to the as-is version using laser scans and other techniques to make the model match the current structure and get to a physical digital twin — but it’s not done yet. The magic happens once those as-is digital twins are connected to the world around them. If you start including information about the school’s HVAC system performance, water and energy usage, and kids’ movement patterns, then you can start making decisions that optimize the building for its purpose.
Bentley’s new iTwin Services wraps iModel, iModelHub, context capture and other technologies into a subscription service that’s intended to get people to build digital twins of their assets. A user identifies which data sets they want to use, and iTwin creates the iModels. The iTwin Service keeps everything in synch via iModelHub, which records each change in a ledger. This is cool: it means that you can step through the asset’s timeline, change by change, but also means that users and ultimately, AI engines, can analyze all sorts of parameters to improve performance or meet other objectives.
We’re already seeing AEC projects make these connections. For example, advanced construction sites manage completion payments by comparing CAD models and construction schedules to the data captured by periodic drone fly-overs. Do last night’s images show that the concrete floor was poured? If yes, spawn a process to pay the contractor. If not, check the contract for the late penalty, yell at the contractor, and spawn a process to update all downstream schedule items.
That’s a relatively simple case, but what if more advanced analytics and artificial intelligence could simulate out the ramifications of that delay? Or automatically identify the delay and notify the project manager? Bentley’s examples were engineering-related (since that’s what they do) but they said that iTwin Services will work with essentially any data type, just as iModels do. It‘s up to the imagination of the user to figure out what data types to connect, to answer the business‘ questions. Bentley will price iTwin Services according to the amount of data being moved around — we’ll see what users ultimately decide to model and monitor.
YII attendees seemed to understand the importance of working towards digital twins, but appeared a bit overwhelmed by the sheer volume of data needed to describe their assets. As always, start small, with a single system or physical unit, test what works and what is superfluous — and then work outwards. And start with a specific goal (reduce electricity consumption by 10%, no schedule slip in the plumbing trade, etc.) to show a quick financial benefit. Bosses love that.
So, what’s iModel.js? And how is it related to iTwin Services? So glad you asked. I‘ll have more on that and why it‘s a game-changer for Bentley later this week.
Note: Bentley graciously covered some of the expenses associated with my participation in the event but did not in any way influence the content of this post. The cover image is of Greg Bentley delivering his keynote, courtesy of Bentley’s photographer.