‘Augmented Reality’ Peers Below The Surface: Technology Could Revolutionize Underground Engineering, Design, Construction

By Jeff Griffin, Senior Editor | October 2013, Vol. 68 No. 10

“Above ground objects are surveyed from these control points using highly accurate survey equipment that employ laser technology or satellite-based positioning that is capable of making measurements that are accurate to within centimeters and elevations changes to within 1/100 of a foot. LIDAR is another widely-used technology that can be used to create near survey grade representations of above ground structures as if wire mesh were carefully molded over everything being measured.”

From this framework, other layers can be added (augmented and enhanced) to provide color and texture and shading to levels of detail that resemble photos. Because many laser scanners today have built-in cameras, draping actual site photos over the point cloud and resulting mesh to create a photorealistic 3D model is relatively easy.

“The data that is being measured comes from the point cloud and resulting site model that in turn can be used to measure to another point of interest or milestone,” Wallbom continued. “The same thing works for below ground because we capture the exact ‘X’ and ‘Y’ [latitude and longitude] location of every square inch of the area being surveyed. Using various geophysical instruments, we capture the ‘Z’ dimension [depth] that is tied to the X and Y locations, providing a 3D dataset that can be looked at from any angle. If I know that some point of reference such as a telephone pole or a building or fire hydrant is located so far from one control point and so far from another, then through triangulation I can know where everything else is in relationship to where I am.

“Two disparate datasets need to be combined: the first being the above ground dataset that came into being through a number of different sources such as Google Maps, photogrammetry technologies from companies like Earthmine and Pictometry or previously completed LIDAR scans done by others which are housed in a GIS database. The second dataset comes from a company like UIT who is capable of providing survey grade 3D digital models of the subsurface that incorporate the same control points as those used for the above ground dataset. Through the magic of the computer, these two separate datasets are merged or in technical terms fused together, so that images are being augmented on the screen change depending on how the operator approaches a given subject and where he/she points the camera lens on the smart device,” he concluded.