In recent years, aerial drones have evolved past military and hobbyist use to numerous commercial applications. One of them is providing newer and more affordable views of critical infrastructure and construction sites. Beverly, Mass.-based Windover Construction is one of only three general contractors in New England using drones in construction.
Unmanned aerial vehicle (UAV) usage on job sites has increased by 239% in the past year, according to DroneDeploy. By 2020, spending on drones in construction will increase to $11.2 billion, part of a global commercial drone market of $100 billion, predicts Goldman Sachs.
The best uses of drones in construction require an “accumulation of knowledge,” said Amr Raafat, director of virtual design and construction at Windover Construction. Robotics Business Review recently spoke with him about what training is needed, the potential for virtual reality and augmented reality, and the value that UAVs can provide to builders.
Training and regulations
“Last July, I became an FAA-certified remote pilot,” Raafat said. “Windover Construction then implemented its drone program.”
“The accumulated process for drones in construction includes learning how to fly drones,” he explained. “At the beginning, some people weren’t sure why we were doing this, but it didn’t take long.”
“The FAA has been really helpful with helping us learn about the weather, frequencies, and BVLOS [beyond visual line-of-sight flights],” said Raafat.
Learning where to use drones in construction
Raafat noted that construction companies should remember three considerations when developing their own drone programs: risk management, the potential time and cost savings, and the tasks for UAVs to conduct. There are many moving parts to keep track of on any construction site, and even the best plans are often inaccurate to the final structures.
“Instead of asking a worker to climb up to inspect a roof or compare a topographical survey against a plan, we can capture maps in 2D and 3D,” he said. “This can help with assessing stock piles and certain phases of laying a foundation.”
“With a 2D map, we can overlay design drawings and see any problem,” said Raafat. “From ground survey points, we can get centimeter or quarter or eighth of an inch accuracy. For every seven meters, we’re only two or three millimeters off.”
“Drone georeference images include longitude, latitude, and altitude,” he said. “When we put the images together, accuracy is important for creating images.”
“You can also use drones for facility management,” Raafat noted. “We have before and after images to capture what we’ve built, and we can input measurement data into systems where it can be used for years in facility management.”
Windover Construction gets value
“The drones are already integrated into our software, but it’s a matter of going a step further into the construction, design workflow,” Raafat said. “We use Autodesk software.”
“DJI’s Phantom 4 is the industry standard, and it’s very reliable,” he added. “With the software and drones, we can image a site in a fraction of the time compared with a ground survey — 10 to 15 minutes, compared with a process taking weeks.”
“We work on high-end academic and residential buildings,” said Raafat. “Drones minimize disruption of the campus in addition to saving time and money and protecting worker safety.”
“Windover Construction combines in-house laser scanning with drone information for complete capture of the exterior and interior experience,” he said. “Drones still need the experience and guidance of surveyors.”
UAVs plus AR, VR
“With virtual reality, we can see the building model, and with augmented reality, we can superimpose the design to see how the building sits,” Raafat said. “It’s all we’ve been doing.”
“While there are very few construction management companies in New England using drones for building modeling,” he observed. “Eventually, everyone will.”
What technology would Windover Construction like next for technology such drones in construction?
“I personally hope that we can find a way to place lightweight elements such as survey flags accurately in, for example, wetlands,” responded Raafat. “We can already accurately determine location, so having drones as a robot onsite would save even more time.”