Mark Franklin, 3D Reality Capture Lead Account Manager, Kleinfelder
Modular construction offers many benefits, but traditionally customization hasn’t been one of them. Modules are typically delivered to the construction site and assembled, and hopefully, there won’t be any fit-up errors.
But imagine if it was possible to assemble all the modules in the manufacturing plant, on the development’s footprint, to make sure it will exactly fit as it should? You’d derive all the quality and cost control benefits of modular development while eliminating any uncertainty about how the modules will fit onto the site.
With 3-D reality capture scanning, it’s now possible to preassemble the building or complex virtually and see exactly how the modules will fit on the site using virtual reality glasses, augmented reality tools such as the Holo Lens, or a computer screen. Using high precision laser scanners (also known as lidar), engineers can capture data about every element of a building or construction site. Applying progressive scanning (as projects are built / at each stage of construction) provides even more detailed information about a building by capturing electrical and piping systems. These internal system scans can then be overlaid with the rest of the building scans, giving the viewer the ability to “see-through” the walls and view internal building elements.
The scanners, which utilize class one lasers, are accurate to 1mm at distances up to 350m away.
3-D reality capture scanning is a valuable tool that can provide enormous benefits when it comes to modular construction
Each scan can vary in time depending on the required quality, but typically it takes about 4 ½ minutes, and entire complexes and worksites can be mapped in a matter of hours, with huge complexes taking just a few days. The scanners weigh about 10 pounds, and a mapping engineer can operate two scanners simultaneously, typically on tripods. The cameras can also be attached to drones or robots to capture difficult to reach or dangerous spaces. The data can be collected live using Wi-Fi connections from the scanner to a laptop, or it can be collected on an SD card located in the camera.
Typically, when a building or site is completely mapped, the data is then uploaded to a computer running various types of Building Information Modelling (BIM) software. Over the past 25 years, BIM has become a standard tool for engineers and architects because it allows them to manipulate elements of a design on a computer screen before the first shovelful of dirt is moved. With 3-D reality capture scanning, the data is collected and uploaded so engineers can use BIM software to work with a detailed and accurate electronic rendering of an existing building or construction site.
While the technology is typically used to map older brown field sites and buildings where detailed drawings and blueprints may no longer exist, 3-D mapping can be useful for other types of projects, such as green field sites and modular development.
In the case of modular construction, the technology would be used to map the site on which the project is being developed. The first step would be to use 3-D scanners to capture the entire site, not just the area where the building is likely to go.
Then, once the data is uploaded to a BIM design program, engineers can use desktop, virtual reality glasses, and augmented reality systems to see how various modules would fit into different parts of the site. Sometimes, design teams find that the module placement they’d planned for isn’t optimal and that the building or complex would work better in a different location on the site or in a different configuration. The program also allows developers to see where infrastructure, such as electric and plumbing, and other resources would best fit into the design.
It’s not just buildings that can be moved around and manipulated. Project managers can also experiment with different placements of various pieces of construction equipment to see how they should be deployed, making the technology very useful for construction management. For instance, the best strategy for lifting modules into a site can be determined by planning crane layouts virtually. In essence, the technology allows project managers and their design teams to complete a virtual run-through of the design, planning, and construction processes to make sure that there are no surprises when it’s time to deliver and assemble the modules.
3-D reality capture scanning is a valuable tool that can provide enormous benefits when it comes to modular construction. It’s imperative that when modules come out of the factory, they will fit seamlessly onto the site for which they are intended. As the cliché goes, “time is money.” Time spent making adjustments and site improvements during the installation process can lead to large unplanned expenses, as well as construction complications. 3-D reality capture scanning can assure that the process goes smoothly, eliminating these unnecessary time and financial headaches.