This post is brought to you by Autodesk Reality Capture

Unless you’re designing a new building that’s slated for construction in the middle of a flat and empty landscape, context matters.

Whether it’s a renovation, an addition, or new construction, the as-is geometry of adjacent buildings, nearby structures, and the surrounding terrain is critical for the design process. But conventional as-built drawings are notoriously unreliable, prompting expensive surveys and time-consuming manual measurements.

However, new technology is quickly changing this situation. Laser scanning and photogrammetry solutions enable the digital capture of spatial information for integration into building design processes. Reality capture technology is not new, in fact, laser scanning originated in the early 1960s. But historically, the technology has been very expensive, data-intensive, and difficult to use.

In the last several years, the cost of capture technologies dropped significantly while ease of use improved dramatically. AEC firms that used to outsource data capture services are increasingly insourcing these services. As a result, reality capture processes have been ‘democratized’, enabling firms of all sizes to quickly and cost-effectively obtain extremely accurate as-built information to support their BIM workflows.

Reality Capture 101

A variety of methods are used to digitally capture the real world, from 3D laser scanners and photogrammetry to ground penetrating radar and coordinate measuring machines. And it should be noted that reality capture is used throughout the building industry (for construction and operations as well as design) and indeed across all industries for a wide range of application such as reverse engineering, inspection, and QA, assembly line planning, and facility management. Laser scanners and photogrammetry are the primary methods used to digitally capture existing building or site conditions.

Laser scanning (also called LiDAR) involves the use of a handheld or tripod-mounted device that beams laser light at its surroundings, then measures the reflected pulses to create a point cloud of millions of photorealistic dots. To capture the interior and exterior of large areas, scans are taken from various locations throughout the site. Using this point cloud data in a building design application such as Autodesk Revit or AutoCAD requires pre-processing in a specialized reality capture application such as Autodesk ReCap. ReCap enables users to automatically register different scans within a common coordinate system and tie that point cloud to a project’s coordinate system. The size of raw point cloud files can reach hundreds of gigabytes for large projects—rendering them almost impossible to work within a modeling environment. The cloud-based tools included in ReCap helps users visualize and edit these massive datasets, and prepare them for use in Autodesk design solutions.

Overlapping photographic images from a digital camera are stitched together to depict existing conditions. The camera is either hand-held or mounted on a drone. Similar to its processing of laser scans, ReCap software merges these images together to create 3D surface meshes, point clouds, or ortho-images.

This as-built or as-is data can then be imported into 3D modeling applications to support the design process. This may involve using the data as a reference while developing new model information around it, or to simulate real-world behavior (such as shadow-casting analysis), or to perform digital as-is versus to-be clash detection.

Autodesk ReCap

A building’s design is vertical in nature, as is its setting. As such, the ability to combine and manage data from ground- and drone-based capture devices is very important when capturing existing conditions for building projects. Unlike most reality capture software products, ReCap software processes both scanned and photographed reality capture data in the single software solution.

For example, designing an addition to a multi-story building in an urban setting requires accurate as-is information for the existing structure, as well as adjacent buildings and cityscapes. This entails the data capture of the building’s interiors, the street-level capture of the building’s exterior and surrounding structures, as well as the capture of roof tops and upper-levels of exteriors. Laser scanners or photogrammetry can be used to capture, floor-by-floor, the building interiors. Scanners or cameras can capture street-based exteriors and adjacent structures. And camera-mounted drones can be used to capture the exterior of the building’s roof and upper levels.

ReCap can automatically process and merge all of this data and gets it ready for direct integration in most Autodesk design tools. It includes a mobile platform, so you can use an iPad for in-field registration and to verify scan quality and coverage. And you can use the cloud to power the processing, providing quick turnaround times on deliverables and eliminating the need for high-end, expensive computers. Moreover, ReCap has a low subscription price: just $300 per year or $40 per month.

Recently, a joint venture from Leica and Autodesk has taken the democratization of reality capture one step further. Leica Geosystems has developed the BLK360—a very small, fast, laser scanner that uses ReCap to control the data collection process. The cost of a standard, industry-grade scanner—capable of capturing the distances required for a typical building project—can range from $75,000 to $100,000. Whereas Leica’s new BLK360 scanner has a retail cost of just under $16,000. In addition to this comparatively low cost, the scanner is extremely easy to use, featuring on-the-fly image and point cloud processing. The ReCap mobile app allows you to automatically register and visualize scanned data in the field via an iPad, and then upload 3D models and panoramic images to the cloud for sharing and collaboration.

The low price and ease of use of ReCap make it ideal for architectural firms. And if firms do need a little help at the beginning, they can turn to Autodesk’s new Services Marketplace. This is website helps Autodesk customers compare, connect with, and hire Autodesk-authorized industry professionals who can help with services such as training, hands-on design, software customization, workflow optimization, and more.  

ReCap in action

Here are a few examples of small firms who have accomplished big things with ReCap.

Scan-to-BIM: FHM Consulting is a small firm in Western Australia that specializes in Scan-to-BIM services. The firm recently provided laser scanning services and as-built models for a new museum being built in Perth. Established in Perth in 1891, the Western Australian Museum has facilities in five sites throughout the state. The Perth location is currently undergoing a major expansion and renovation. The original museum occupied Perth’s ‘Old Gaol’ building, which still forms a large part of the museum. The Perth museum grew to encompass other heritage buildings, including Hackett Hall, and the Jubilee and Beaufort Street Buildings. The $428.3 million new museum project consists of the integration of a new building with these heritage buildings.

Since all of the heritage buildings will remain intact with the new structures working around them, precise measurements proved crucial. Although the state government supplied ‘Scan-to-BIM’ models as part of the tender, the project team felt that some of this information was inadequate for their needs and contracted FHM Consulting and 4D Delta, which specializes in spatial imaging services, to deliver new as-built models.

This team scanned and modeled over 40,000 square meters—including three museum wings, the Old Gaol, an underground parking garage, as well as an adjacent concourse and nearby streetscapes. They used Faro and Leica scanners to capture over 600 scans of the project and ReCap to process the scans. FHM Consulting then used the resulting point clouds in Revit for its modeling efforts. In addition, 3D points were extracted from the point clouds to generate a surface mesh and terrain model of the surrounding site and concourse.

Renovation: Canadian firm Turner Fleischer used reality capture for one of its recent design project: the conversion of existing office space into an urban food store. Located in downtown Toronto, the 12,000-square foot project includes the partial renovation of two levels of the office building. The ground level will house the store itself, but this space has minimal headroom clearances. In addition, the designers had to contend with the existing building services that needed to remain as well as the new services needed for the store. Knowing that these close quarters would prove challenging, Turner Fleischer decided to perform a detailed laser scan of the space to determine the exact dimensions of the existing structure and building services. The precision of the scanned data would help the designers maximize headroom and décor heights while accommodating the existing and proposed building services.

Using a FARO Focus3D X 330 scanner, the team captured 63 scans. This reality-captured data was then processed using ReCap. The resulting point cloud was linked to the firm’s Revit design model and used for further design development and clash detection. The firm had already completed a design concept in Revit, using as-built drawings of the space for spatial coordination. But when the team merged the point cloud and the Revit model, it was obvious that these as-builts were not, in fact, as-built.

By using the point cloud and the Revit model for coordination, Turner Fleischer resolved many design conflicts by making minor design changes—moving lighting or signage, expanding or lowering bulkheads, revising column cladding, and so on. In other situations, where design changes would have compromised the quality of the store’s décor or its operation, the landlord relocated the interfering building services. And when services could not be relocated, Turner Fleischer and the mechanical consultant created several different design options that would simultaneously accommodate the needs of the store functions while minimizing the need to lower ceiling heights. The team then reviewed the proposed options (in the context of the scanned reality-captured data) with the client to help them make more-informed design decisions.

By finding and fixing conflicts prior to construction, Turner Fleischer helped its client avoid unnecessary replacement of expensive equipment such as compressors or refrigerated cases, construction delays and cost overruns, delay of the store opening, and a diminished customer experience. In fact, the firm estimated a 325% ROI for its use of reality capture on this project. The ROI was determined by comparing the cost of the laser scanning and processing to discover and resolve interferences during design, versus the approximate cost of resolving the issues during construction.

Conclusion

Reality capture is quickly becoming the norm for building design and construction. New hardware and software advances allow architectural firms to quickly and cost-effectively capture information for design context. If your firm isn’t already using or investigating reality capture, now is the time, or you risk being left at a competitive disadvantage.

Learn more about Reality Capture and download our eBook.