An interview with Amir Rubin at PARACOSM+ Raffi Holzer at AVVIR about their new technologies that will likely make BIM much easier to update, and better for all.
FUEL: Tell us about the problem construction faces that your technology would help to solve.
Amir Rubin, Paracosm:
The solution we’re creating is for construction projects—usually commercial—that are following a full BIM (Building Information Modeling) or VDC (Virtual Design and Construction) process.
These projects are designed and coordinated around BIM. However, what actually ends up getting built in the field is not necessarily what the BIM model specified. This can lead to major problems, since the BIM model is no longer a “source of truth” reflecting the actual state of the job site.
In general, there really haven’t been efficiency or productivity gains in the field of construction like there have been in every other manufacturing field.
There are a few reasons for this, one being that in manufacturing you can control the environment. The other thing is that manufacturing can control the process. The secret is having a feedback loop.
Paracosm + Avvir are able to bring in a control process feedback loop to construction projects. It will be a way to answer what are you building, and does it match the BIM model. This empowers contractors and project managers to know when there’s been a deviation in as-built versus BIM and will let them take action immediately.
FUEL: Why hasn’t it been easier to create such a feedback loop in construction?
[Amir R.] Right now you have a BIM model, the construction team goes out and builds it, and you kind of pray that they did it correctly.
There are two parts of the feedback loop that are missing. The first is how to capture the job site, and the second is how to analyze it.
In order to know what’s going on on the job site, you need a way to effectively digitize it. Until now, the only way was with tape measurements. Tripod laser scanners have also been used; they’re incredibly accurate but incredibly slow. With a tripod laser scanner, it can take days to fully capture site and capture data. By the time all is captured, it’s already a huge, tedious project. You’re not going to get feedback fast enough to make part of a weekly QC process.
FUEL: So that’s where Paracosm comes in. Can you describe your product?
[Amir R.]Paracosm has developed a handheld 3D laser scanner [the PX-80]. No special training is required to use it. Anyone can walk through a worksite and capture the data, hit a button, and after some processing time, (10-minute scan might take 30-40 minutes to process, whereas a 2-hour scan can take a few extra hours) the scanner spits out 3D scan file (i.e. a point cloud) representing all measurements available on the site.
What PX-80 puts out is not a 3D model, it’s a 3D point cloud. It’s a digital representation of the work site as seen by camera and Lidar system. Each point represents an accurate 3D measurement, so it looks like a digital replica of the work site. It contains all the measurements and info you need to do an analysis of a construction site. But, in its raw form, it’s a big heavy file that people don’t know how to work with directly, which brings us to…
FUEL: Let us guess—Avvir! So Raffi, want to tell our readers how Avvir works?
Raffi Holzer, Avvir:
Yes, but first let me back up for a second. Paracosm’s scanner runs on a SLAM-based algorithm (Simultaneous Location and Mapping). The same technology that allows a driverless car to know where it is in space, enables PX-80 to know where it is in space.
With a traditional laser scanner, you have to set it up in a room and set a geolocation point. Paracosm already knows where it is. PX-80 scans stitch themselves together. I can walk around with scanner while I use it. Post-processing goes away as well. This is what makes PX-80 exponentially faster than traditional laser scanner.
[Amir R.] GPS on the work site isn’t sub-centimeter-level accurate enough, so we need this special SLAM algorithm. With PX-80, as the camera and laser are collecting imagery, they’re calculating your position at 100x per second.
[Raffi H.] When BIM was invented, it was intended to be a digital twin of the building it was modeling. Unfortunately that never came to fruition, because keeping BIM up-to-date is incredibly costly and work-intensive. We wanted to close that feedback loop within the realm of BIM so that it could really represent what was going on in building. We needed a tool like Paracosm to make that work, to be able to to sufficiently scan the sites and bring data back into the BIM.
FUEL: So can’t people just look at the point cloud produced by PX-80 and see what’s out of spec between the site and BIM?
[Raffi H.] Even the most advanced contractor who might try to overlay point cloud onto BIM wouldn’t have much luck, because point clouds were never meant to be human-readable…they’re machine language.
So Avvir takes the point cloud and overlays it on BIM, finds the deviations, and represents them in the BIM itself. We present you a recolored, altered version of your BIM to show you where things may have gone wrong.
FUEL: So how does it work, in plain English (or contractor English)?
[Raffi H.]Let’s say you have a column that in your BIM is in position X. Based on your laser scan, however, that column has been placed in position Y. We highlight that column in your BIM red, basically telling you the column is out of spec or out of tolerance. Then we show you via a translucent ghost element where the laser scan has found that element to be in reality.
We make the content of the laser scan easily consumable for people—including a super, project manager, or laborer on site—so that they can take action on it the same day.
FUEL: Describe to me how the full benefits of your technologies (PX-80 and Avvir) would play out for a contractor.
[Amir R.] The immediate benefit—what we’re doing right away—is to tell you something is out of spec and not following BIM. Then the PM or super can say, ‘Hey, I’m aware this is 6 inches or 1 foot off, and it’s okay’. Or, ‘This is going to cause a disaster later on, we’ve got to do the rework right now when it’s easy’. It’s an immediate way to avoid huge rework later. (This video offers a demonstration of how Avvir software works.)
But there are also other, deeper implications when companies eventually adopt this workflow through the life of projects. You’ll have a constant snapshot of exactly what’s happening every week or even every day, however often you want to scan. You’ll be able to build really accurate project tracking systems. You’ll know you have 80 per cent of the structure or 75 feet of ductwork installed. Execs will have visibility data to tie to invoices and schedules, not just guesswork or assumptions. This will have a huge impact on how they manage projects.
[Raffi H.] We came at this from the idea of making BIM that digital twin [of a project] it was initially envisioned to be. In the instant that column is not where it’s supposed to be, you know it. And even if your engineer says it would be cost-prohibitive to change it now, you still want the BIM to reflect the reality of the site. Now, with the click of a button [in Avvir], you can make changes to the BIM to have it reflect reality without having to go to your architect.
And then BIM becomes a source of truth—people trust BIM. It becomes a true hub for coordinating projects. Establishing a trust and faith in BIM will improve all sorts of communication problems that currently occur on project sites.
Paracosm and Avvir are in the process of connecting with chief innovation officers at large construction companies, and have plans to test with a few select companies in first half of 2018. Anyone interested in participating in a pilot project using PX-80 and Avvir should contact them.