Tuesday, January 29, 2013

Pompeii Aerial Survey Project

Pompeii - Bird's eye view of the large and sma...
Pompeii - Bird's eye view of the large and small theatres, Pompeii. (Photo credit: Brooklyn Museum)
In September 2012 the Pompeii Aerial Survey Project conducted a successful aerial photogrammetric survey of the insula, utilising remote-controlled drones, in support of the EPUH project and the Pistrina: les boulangeries de l'Italie romaine project of the École française de Rome (that has been conducting a study of the bakery in the southwest corner of the insula). The aim of the project was to test the application of aerial drone technology in the documentation and survey of built structures in an archaeological context (Pompeii) against traditional methods of architectural investigation. This was the first time that aerial drones had been successfully employed at Pompeii for aerial photography; indeed, previous aerial photography had traditionally used balloons! 

Our approach was twofold: first, to use the aerial drones to take geo-referenced HD geo-referenced digital photographs in order to develop a 3D photogrammetric point cloud model of the insula. Second, we also employed a laser scanner in order to provide a framework for the digital model but also to allow us to compare the merits of the two methodologies.

The drones and their pilots, who have great expertise and experience in flying them, were generously loaned to us by Landinspektørfirmaet LE34 (see acknowledgements below). The drones offer a previously unparalleled opportunity to remotely and quickly survey standing structures. The drone typically flies for 12-30 minutes at a time and can follow a pre-programmed set route or altitude; it will come back to you at the press of a button, while its flight can be followed by a small inbuilt camera. The attached camera can take HD photographs or films including 360 degree recordings. The drone has several on-board gyroscopes and GPS devices that allow it to maintain a safe and consistent position even in windy conditions! These features enable the drone to take geo-referenced HD photographs, which are accurate down to 0.01m. This is simply impossible from traditional balloon-based cameras or even other highly sophisticated aerial survey methods. Furthermore, the drone can take many hundreds of photographs in a single flight so our method also allows us to complete the photogrammetric survey far more rapidly than by a traditional hand-held method on the ground, which can be highly time-consuming and is often problematic given the importance of camera position in photographing high walls or features. However, it was necessary to supplement the drone photographs with a number taken with a hand held camera. This was necessary given the high number of very small spaces in the insula that were simply too small or narrow for the drone to adequately photograph.

For detailed specifications on the drones click here: LE34