Inside Unmanned Systems provides actionable business intelligence to decision-makers and influencers operating within the global UAS community. Features include analysis of key technologies, policy/regulatory developments and new product design.
Issue link: http://insideunmanned.epubxp.com/i/813246
30 unmanned systems inside April/May 2017 SPECIAL REPORT INDUSTRY TRENDS The technical setup included a Heliceo Fox6 multirotor drone equipped with a ProMark SP80 GNSS module and Sony Alpha 6000 Camera. With just two people working the mission on-site, the Fox6 crisscrossed a wide area from an altitude of 80 meters above the basilica, travelling at five meters per second. A second drone, a DJI Phantom 2 with GoPro Hero3+ Black Edition, was also used for one circular f light around the monument. "The Basilica is situated in a tight urban environment," Houdr y explained, "so for safety reasons, we used the lesser-perform- ing Phantom 2 to get details in certain areas where there was very little space between the Basilica and the neighboring buildings." The entire mission took just two hours to perform, including the installation of ground control points. The crew also scanned the Basilica interior using a Leica P20 3-D Scanner. All of the processing took a day and a half using Autocad Map and Leica CloudWorx software, to achieve a resolution down to 5 mm. Houdry said drone-based photogramme- try was the only way to do the job, because the size of the building and the distances in- volved would not have allowed the survey to be carried out by terrestrial methods such as tacheometry. "This technique was better than classical acquisition methods," he said, "for one thing because it is exhaustive; unlike with a tache- ometer where the operator chooses what he measures, with photogrammetry, everything in the picture is measurable. So there's not much chance of forgetting something and hav- ing to return to the site." Another advantage, Houdry said, is speed: "We did the job in a third of the time it would have taken us to do it with a tacheometer." Houdry and company subsequently applied the same methodology to another assignment involving the 3-D modeling of an abandoned industrial property, as part of a building Heliceo worked with fellow French company SELARL HOUDRY to build a full 3-D map of the Basilica of Notre- Dame de Liesse. It took just two hours for a two-person team to capture the details of the Gothic landmark using a Fox6 multirotor drone equipped with a ProMark SP80 GNSS module and Sony Alpha 6000 Camera. A DJI Phantom 2 was used to capture details in areas where space was tight. The crew also scanned the Basilica interior using a Leica P20 3-D Scanner.