Drone Mapping Creates Digital Record of Endangered Archaeological Sites

Research Group Uses DroneDeploy to Create a 3D-Printed Model of Ecuador’s Pucará of Salitre

The landscape of Ecuador is littered with archaeological sites, important evidence of the country’s rich, complex history that spans from Paleoindian times all the way through to the Spanish conquest of the Incas. But a lack of resources means that there is still no accurate record of many of these sites. Documenting archeological sites through traditional methods is slow and labor-intensive, and with natural disasters and human development threatening to damage many of the country’s important sites, archeologists who seek to study and preserve Ecuador’s history are often in a race against time. Drone mapping provides a fast, accurate and noninvasive way to document archeological sites, creating a historical record of a country’s cultural heritage and giving archaeologists a rich set of data and models to be used for further research.

In 2013, in an effort to demonstrate that drone mapping technology is a viable solution in the field of archeology, Benoit Duverneuil founded the research group Aerial Digital Archeology and Preservation. Benoit originally studied history, geography and cultural administration before eventually obtaining a Master’s Degree in computer science and embarking on a career in computer science and data analysis. Since 2010, he has combined his loves of history and technology by experimenting with drones at archeological sites around the world. The Aerial Digital Archeology research group aims to further the field of drones in archeology and train others to implement the latest techniques. Along with his research, Benoit also teaches drone technology to both college students and archaeology professionals.

With team members Dorian Roque, Justin Grabenbauer and German Molina, Benoit recently embarked on a project to record three endangered sites in the Cotopaxi Province of Ecuador. The group’s work has shown that drone mapping is an efficient method for creating high-quality maps and 3D models of archeological sites.

Team members using drones to map the Pucará of Salitre

Mapping the Pucará of Salitre

Built toward the end of the expansion of the Inca empire, the Pucará of Salitre is the site of Inca and Pre-Inca fortress ruins — a series of manmade terraces, ditches and walls built in a concentric circle atop a hill. The biggest concern for archeologists is that this hill is located on the Northern slope of the active Cotopaxi Volcano. The volcano is classed as one of the most dangerous in the world, and based on its history, it is due for another major eruption. If this happens, there is a good chance the large glaciers located on the volcano’s flanks will rapidly melt, causing mudslides that could damage or completely cover important sites like the Pucará of Salitre and sixty-seven others that have been identified in the region. Benoit and his team members realize that if they don’t work quickly to create maps and models of these sites, then a record of their existence could be lost forever.

Of the endangered sites in the region, the group chose to first focus on documenting the Pucará of Salitre and two other, more modern historical sites. They hope that this small project will demonstrate the possibilities of drone mapping technology and ultimately allow them to scale the project with the help of Ecuador’s Ministry of Culture. Long term, their goal is to train local archeologists in the use of drone mapping technology and empower them to help digitize thousands of archaeological sites in a large database that will be made available to the scientific community. In addition to this database of records, they intend to use high-resolution maps and 3D-printed models to bring archeological sites to life for the public. By creating a greater public awareness, they hope to help minimize the looting that often takes place at historical sites and also promote responsible, less invasive tourism.

“We’re excited about the opportunities that are available. We can create models and visualization of the data that are very insightful to professionals. Also, we can record something that might get lost at any time and provide testimony for future generations.” -Benoit Duverneuil

To map the Pucará of Salitre, the team used a DJI Inspire, equipped with a Zenmuse X5R camera, as well as a FLIR thermal imaging camera. They flew the 4.21-acre site at an altitude of 100 feet. Because no Wi-Fi was available in the remote location, they used DroneDeploy to pre-plan their mission. Once on site, they captured 181 pictures, including manually captured oblique imagery. They uploaded the images to DroneDeploy to process the map, which they then used to produce a set of data and models.

A total of sixty-eight archaeological sites are in danger of being damaged if the Cotopaxi volcano erupts.

Drones Offer Faster, Less Invasive Option for Archaeologists

Although it seems impossible to anyone immersed in the world of UAVs, the go-to method that aerial archaeologists use to document a site like this is kites. As in: program a camera to automatically take pictures, strap it to an ordinary beach-flying kite and let it loose. Sometimes they use helium balloons or helikites, but the general idea is the same. Most archeological sites are just too small for manned aircraft photography to be feasible. A ground survey is sometimes an option, but it is time consuming and runs the risk of causing damage to a fragile site.

“Drone maps are a game changer,” says archeological researcher Benoit Duverneuil. [click-to-tweet]

Needless to say, kites and balloons are a less-than-ideal solution for documenting archeological sites. For an area like the Pucará of Salitre, spanning less than an acre, it could take between three to five days to capture the right images this way. Once this time-consuming process is finished, the pictures can be used to create a visual record, but they are not adequate for further analysis and data interpretation .

Compared to the five days it would have taken to capture the Pucará with traditional methods, Benoit’s team spent a total of fifteen minutes flying the site with their drone. Once they were back in reach of Wi-Fi, they uploaded their images to DroneDeploy in ten minutes and spent another five hours processing the data into various outputs. When they were done, the team had a comprehensive orthomosaic map, elevation data and a high-resolution 3D model, all acquired in less than a day’s time. This rich data set was gathered five times faster than with traditional methods, and it was all done without treading on the fragile landscape.

Orthomosaic map of the Pucará of Salitre

3D-Printed Models and Infrared Sensors Provide Exciting Opportunities for Analysis

Benoit and his team are especially excited about the amount of data they can capture with drone mapping technology. They hope this information will be used both for scientific research and also to help the public recognize the beauty of these sites and how important it is to preserve them.

To this end, the team is experimenting with the best ways to make 3D printed models of the sites they map. 3D printing is already used as a tool to recreate historical artifacts for museum and art house exhibitions. Benoit points out that it not only helps preserve artifacts, but it also makes them more accessible and tangible to the public. After mapping the Pucará of Salitre, he and his team used the 3D model they generated in DroneDeploy, exported the model into 3D software and transferred it to a file format that is suitable for most 3D printers. They are currently experimenting with different materials, colors and scales to find a method that creates the best possible 3D-printed model.

In terms of creating quality data for scientific research, the team’s GIS expert will import the 3D point cloud from DroneDeploy into ArcGIS and analyze the site’s location compared to the expected progression of lava and mudslides after a major volcanic eruption. They have also equipped their DJI Inspire with infrared and multi-spectral sensors. Grass growing on top of rock structures is often stunted, and in the infrared color spectrum, it appears as a different hue. This information may help reveal previously undetected underground buildings.

3D model of the Pucará of Salitre, created in DroneDeploy

Research Team Plans to Use Drone Mapping for Further Collaboration

With the success of this project, the Aerial Digital Archeology and Preservation research group hopes to show that drone mapping is a viable way to record and analyze archeological sites. Eventually, they plan to train and empower local archeologists to continue this work and ultimately create a worldwide database of endangered archaeological sites that can be used for preservation and study.

Benoit appreciates the part that DroneDeploy could play in this endeavor, especially considering many archeological sites are in remote areas. “In the field, we often don’t have access to technical communications,” he points out. “That’s why DroneDeploy’s pre-planning feature is very great for us. We were able to pre-map the mission within a large area, load satellite imagery of the area and then make adjustments to our map on the ground. This is a tremendous advantage.”

Where to Learn More

If you’re interested in learning how to make a 3D model using DroneDeploy, or looking for tips and tricks to improve your models, be sure to check out our Beginner Webinar Clinic. You’ll find a great discussion on best practices for creating drone-generated 3D models and much more.

Get Started with DroneDeploy

Want to learn how DroneDeploy can help your business? Visit www.dronedeploy.com to start your free trial or request a consultation with one of our team members. The DroneDeploy mobile application is available for free download for both iOS and Android devices.