Architect Magazine Ι August 2018
The use of drones to survey project sites is becoming more common among builders and engineers. For architects, unmanned aerial vehicles (UAVs) offer a distinct vantage point from which they can study and document sites for research and marketing opportunities. Below, practitioners and operators discuss strategies for incorporating UAVs into design workflows.
The Benefits
Drones are useful for architects throughout the design and construction process, from preliminary site analysis, to tracking construction accuracy and progress, and to documenting a completed project.
Russell Thomman, an associate project manager at Stantec’s Austin, Texas, office, says his team uses drones for virtual site visits when it’s too expensive, impractical, or unsafe for an entire team to travel. For example, he says, safety can become an issue in Texas where “snakes in tall grasses” are not uncommon.
But drone technology can also inform design choices. For a local mixed-use condo project, Thomman and his team took 360-degree photos every 50 feet before ground was broken at the site. Though initial plans called for positioning the building to the west, the team realized through the drone imagery that the building would essentially face a parking garage and the back of a hotel. They opted to reorient the project toward the east to overlook an expansive greenbelt. “It completely shifted the mindset of the entire design team,” Thomman says.
San Francisco–based drone imagery and data processing company Skycatch offers hardware and software that can photograph and geo-locate objects with an accuracy of less than 2 inches, all without requiring external physical benchmarks that some systems need to orient a camera’s view. And some of Skycatch’s UAV packages include a photogrammetry engine accessory that can convert raw imagery into several mapping file types in the field—enabling users to download and access images on a smart device without an internet connection or the need to return to the office.
This high level of accuracy means that “architects [can validate] their design with what [contractors] in the field are executing,” says Tom Zaiderman, senior project manager at Skycatch.
Skycatch’s eponymous app platform allows drone operators to upload raw drone imagery (gathered after automated flight routes that scan an indicated area) and have it translated into various mapping file formats that can be shared among teams. This can be 3D imagery with rich surface texture and detail, elevation and topographic maps, as well as point clouds to be uploaded into various software programs such as Autodesk Revit or Navisworks for BIM applications.
“The ability to get a tremendous amount of information out to a very large group of people can save hundreds of thousands of dollars in changes that may not have been detected until later, and would be very costly to fix,” Thomman says.
The Rules
While it is possible to outsource drone photography to specialists with the appropriate licensing and equipment, tech-savvy firms can opt to try it in-house. However, understanding of the latest aviation laws is vital. In August 2016, the Federal Aviation Administration (FAA) released Part 107, which offers the most detailed set of regulations governing the commercial use of small unmanned aircraft to date.
Part 107, in conjunction with other regulations, dictates that commercial drone pilots—which include anyone using a drone for work, business purposes, or any sort of compensation for hire—must always keep their drone in their line of sight, flying no higher than 400 feet and no faster than 100 mph. In general, flying within 5 miles of an airport is discouraged and drones must yield to crewed aircraft. The FAA B4UFLY app offers UAV rules for a given area.
Most importantly, commercial drone pilots must pass a two-step testing and registration process. The FAA’s $150 remote pilot certification test, offered at hundreds of locations across the country, covers aircraft classifications, the effects of weather, emergency procedures, and more. (See a list of study materials, aggregated by the FAA.) Prospective pilots must register online with the FAA through the Integrated Airman Certificate and Rating Application System.
But before investing money and time in purchasing and operating a high-end drone, Thomman recommends starting with a cheaper consumer drone—“something with a camera that you can fly in the park that you’re not going to be too upset if you crash.” For example, DJI, a large manufacturer of consumer drones based in Shenzhen, China, offers the entry level Tello for $99, but its higher-end, professional-grade models are between $1,000 and $3,000.
The Limitations
The technology enabling drones to turn imagery into data is still advancing, but the imagery that UAVs capture has already charmed the greater public, making it particularly useful in project promotion. “Clients are still wowed by it,” says Shann Rushing, AIA, a principal at Clark Nexsen in Raleigh, N.C., who also edits and packages the firm’s drone imagery for project pitches. “It’s not expected yet, unlike 3D renderings.”
But just because clients are fascinated by this means of visualization doesn’t mean it should become the centerpiece of project photography. Drone imagery of architecture is most evocative when it grounds a location in its context, like Navy Pier amidst Chicago’s skyline, or the Golden Gate Bridge jutting through San Francisco Bay.
Last year, Milwaukee-based architectural filmmaking company Spirit of Space incorporated two clips of drone video footage into a six-minute video of a conceptual residence by Steven Holl Architects in New York. These snippets impart a sense of sylvan isolation and the scale of surrounding landscape, but don’t try to explain the space of the house itself. “Superman fly-throughs don’t really communicate how we, as humans, experience space,” says Spirit of Space founder Adam Goss. “For us, it’s another tool in the tool belt.”