Virginia Tech uses handheld laserscanning for VR project

Industry

Education

Time

Three times
faster than
terrestrial
sensors

Location

Vauquois,
France

Size

Several
kilometres

Scanned

Battlefield
tunnels

The Vauquois battlefield in France tells a little-known story of mining warfare during World War I. Through four years of combat which saw the hilltop village of Vauquois completely destroyed, French and German troops dug miles of tunnels under each other’s positions to plant explosive mines that would ‘bomb’ the enemy from below. More than 14,000 soldiers died there.

Vauquois must be experienced firsthand to understand the difficulties – and despair – of living deep underground in wet, cold and cramped conditions for days at a time. Of course, not everyone can travel to France and crawl through the remaining tunnels in person. So, a group of researchers at Virginia Tech is bringing the battlefield to classrooms and museums with the help of reality capture and virtual reality (VR) technologies.

 “We built a large virtual environment that includes physical models of the [tunnels] so you can reach out and feel real things while wearing VR goggles. It’s all derived from laser scanning,” said Todd Ogle, Executive Director of Applied Research in Immersive Environments and Simulations at Virginia Tech.

Combining efforts of the University Libraries, Dept. of Visual Arts and numerous other disciplines, the Visualizing History team first travelled to Vauquois in north-eastern France with funding from a federal grant in 2016. Over 10 days, they used a traditional stationary laser scanner to capture details of the pockmarked battlefield terrain.

It was a game changer in terms of the speed of data acquisition

Their progress slowed considerably, however, when they attempted to scan inside the tunnels, recalled Phat Nguyen, a Virginia Tech Visual Arts professor.  “There were tight spaces we couldn’t get our terrestrial scanner into…and it was time-consuming to repeatedly set up the device to scan small areas,” said Nguyen.

Just days before the team’s next France trip, they acquired a GeoSLAM ZEB Horizon in the hope of making their time onsite more efficient. The small handheld device did not disappoint.

With no formal training other than the operator’s manual, the team captured scan data inside the tunnels with the GeoSLAM unit more than three times faster than with the stationary scanner. And they used the ZEB Horizon above ground as well, scanning the narrow trenches, wide bomb craters, and a church foundation.

 “Speed is critical when you’re working on a strict budget.” said Nguyen.

Not only was the data collection faster, Nguyen found the team could work more efficiently because the GeoSLAM software processed the scan data into a point cloud on their laptop in real time. They saw where data was missing so they could go back and collect it before leaving the site. This created a much more accurate and complete virtual environment.

Back on the Virginia Tech campus, the team engaged the expertise of students and faculty from numerous departments – Visual Arts, History, Education, Computer Science, Mining Engineering, and Cinema – to build a life-size model of a tunnel and generate the virtual environment of the battlefield. This allows students wearing VR headsets to ‘walk’ through the scene, experiencing it with both sight and touch.

The speed and accuracy of the ZEB Horizon are game changers for educational and historic preservation VR projects like this one because of time and budgetary issues. VR data processing is extremely time consuming, which means time saved scanning in the field make grant money go farther in the computer lab. The result is a more realistic and believable experience.

The Virginia Tech Visualizing History team isn’t stopping with creating educational experiences from their 3D data collection. They are beginning to apply their VR capabilities to other commercial applications of mobile laser scanning.