After two skyscrapers, two Peregrine Falcons, and 7 days in the field, we had a complete model. Drones have been used for many purposes across the board, but we had yet to see them used specifically for the purpose of 3D Mapping an entire skyscraper. At Infinite 8 Institute, our Drone School endeavored to test the hypothesis of whether it was indeed possible to create a 3D Model of a skyscraper, utilizing current drone technology and known best-practices. Our research proved that it is possible to 3D map a skyscraper using a drone, however, the industry must address many challenges if drones are to become truly integrated into dynamic urban settings.
Mission: Initially, in our hometown of Omaha, NE, the most iconic large structure is the Woodmen Tower. The Woodmen Tower was completed in 1969, is 30 stories high, and 478 feet tall. Our main concerns with mapping the structure, involved the strong winds around the skyscraper. Accelerated winds near skyscrapers are caused by the “downdraught effect”. Essentially, when winds run into the surfaces of the structure, they move in all directions around the structure, creating increased wind speeds, and unstable air. High winds, and unstable air can spell disaster for a drone. It was chosen to fly on days where the wind speed was no more than five miles per hour.
Materials: While flying, we utilized the DJI Mavic Pro and DJI Goggles to capture model images. We had one Remote Pilot in Command flying the drone, while one student manned the DJI Goggles as the aerial photographer, and 4-7 other students and staff served as Visual Observers on the four corners of the structure. Each crew member also wore orange safety vests. The local airport manager was notified and each mission was also reported via 1800wxbrief.com.
Methods: The critical tool to the mission was the use of the DJI Goggles, which allowed the drone pilot to completely focus on flying and watching out for obstructions. We believe this also allowed for enhanced data capture, by allowing the aerial photographer to completely focus on capturing images, making for better data. We captured over 1,000 images total, capturing images on each side of the structure, and at equally spaced altitudes the length of the building. All flight was conducted manually, and absolutely no flight around skyscrapers is recommended to be conducted using automated features, as the environment is too dynamic to not have 100% control at all times.
Dangers: During flight, in the downtown environment, the biggest danger we faced came from birds. During low altitudes, we noticed how pigeons exemplified swarm behavior, detecting the drone as a threat to the flock. At high altitudes our drones were challenged by two Peregrine Falcons, who, we assumed, were likely guarding their young. Peregrine Falcons, by the way, are the fastest animals in the world, swooping down on prey as fast as 200 mph, and thus we knew our drone didn’t stand a chance. As long as we kept as safe distance of at least one city block away horizontally and vertically from the roof of the building we were not threatened.
Also, there is the threat of losing the radio connection between the controllers and the drones. Therefore, it is imperative to keep a clear line of sight between the remote controller and the actual drone. Something else cool we noticed, is that even if the controller signal would go out, the DJI Goggles still had a strong signal, and served as a critical backup for safety on such a dangerous mission.
Surprises: We were surprised to see the elevation view of the completed 3D Model. It was easy to determine areas of the downtown topography that are prone to flooding. We see such a tool as this, as a powerful addition to the methods and resources of city planning departments, and governments around the world.
Challenges: The biggest challenge for us was completely unforeseeable. After completing the initial models, we discovered that there was an ugly hole in the skyscraper next us, which was the First National Bank Tower (FNT). The FNT completed in 2002, is 45 stories tall, and 634 feet in height. As a result of the prominence of the FNT, we were forced to map it as well, which required additional time in the field, as well as manipulating the final model in the lab. However, we are happy we spent the extra time as the model reflects it.
Industry Insights: Our work in the downtown environment, allowed us to have experience utilizing some of the most advanced commercial drone technology currently available to professionals and consumers. The biggest threat to drone deployment in urban settings, we believe, are birds, in addition to the downdraught effect. Commercial Drone Technology manufacturers, and software developers, should test prototypes around large natural objects, such as mountains and ridges to test for the downdraught effect. Manufacturers could easily test for bird interactions, but the drone must have a deterrence for fowl, that does not impact the animals negatively in anyway. While there is current research and testing in this area, any negative impact has yet to be validated.
In the future, when cities become truly ‘smart cities’, buildings will have sensors and will be able to detect obstacles and communicate with drones. Window cleaning drones will have to communicate with “smart windows”, which will have sensors that communicate distances and altitude to the drones. These are all undeveloped technologies, which are likely to take time, but we foresee them coming nonetheless.
Industry Opportunities: We see many opportunities for this technology to be used by Construction Companies for site development, and project management. We believe this use case has many implications for municipalities as well as historical preservation organizations, to save a snapshot of a large area with more depth than a 2D picture. Also, in coastal areas effected by storm surges, the opportunity to use the technology to map variances in elevation, would allow for state and municipal officials to better prepare and strategically utilize resources.
Area: 224 acres.
Conclusion: Overall, mapping these twin towers was the most difficult job that we’ve taken on thus far. We believe that the value such data will provide to customers is undeniable. However, the dangers and challenges that drone teams will face can not be understated in dense urban environments. As the commercial drone technology sector grows, we look forward to being a part of it.
Students & Staff: Ean Mikale, JD, Tyrone Kartchner, Julian Bingham, Laresha Swiney, Regina Finazzo, Jamme Collins, Adonna Bryant, and Deja Smith.
Ean Mikale, J.D., is the creator of the National Apprenticeships for Commercial Drone Pilots and Commercial Drone Software Developers. He is also the Founder of The Drone School, a serial Dronetrepreneur, current participant of the NVIDIA Inception Program for AI Startups, IBM Global Entrepreneur, and member of the National Small Business Association Leadership and Technology Councils. Follow him on Linkedin, Instagram, and Facebook: @eanmikale