Mobile LIDAR holds promise for rapid and precise ground surveys
16 March 2013
Imagine driving down a road a few times and obtaining in an hour more data about the surrounding landscape than a crew of surveyors could obtain in months.
Mobile LIDAR was used to make this image of Glitter Gulch near Denali National Park in Alaska, with some nearby unstable highway slopes (image courtesy of Oregon State University)
Such is the potential of mobile LIDAR (Light detecting and Ranging), a powerful technology that’s only a few years old and promises to change the way we see, study and record the world around us.
A new report on the uses and current technology of mobile LIDAR has just been completed and presented to the Transportation Research Board of the US National Academy of Sciences. Its intention is to help more managers and experts understand, use and take advantage of this science.
The full exploitation of the technology, however, faces constraints. Too few experts are trained to use it, too few educational programs exist to teach it, mountains of data are produced that can swamp the computer capabilities of even large agencies, and lack of a consistent data management protocol clogs the sharing of information between systems.
“A lot of people and professionals still don’t even know what mobile LIDAR is or what it can do,” said Michael Olsen, an assistant professor of civil engineering at Oregon State University, and lead author of the new report. “And the technology is changing so fast it’s hard for anyone, even the experts, to keep up.
“When we get more people using mobile LIDAR and we work through some of the obstacles, it’s going to reduce costs, improve efficiency, change many professions and even help save lives,” Olsen said.
LIDAR has been used for 20 years, primarily in aerial mapping. Pulses of light up to one million times a second bounce back from whatever they hit, forming a highly detailed and precise map of the landscape. But mobile LIDAR used on the ground, with even more powerful computer systems, is still in its infancy and has only been commercially available for five years.
Mobile LIDAR, compared to its aerial counterpart, can provide ten to 100 times more data points that hugely improve the resolution of an image. Moving even at highway speeds, a technician can obtain a remarkable, three-dimensional view of the nearby terrain.
Such technology could be used repeatedly in one area and give engineers a virtual picture of an unstable, slow-moving hillside. It could provide a detailed image of a forest, or an urban setting, or a near-perfect recording of surrounding geology. An image of a tangle of utility lines in a ditch, made just before they were backfilled and covered, would give construction workers 30 years later a 3D map to guide them as they repaired a leaking pipe.
Mobile LIDAR may someday be a key to driverless automobiles, or used to create amazing visual images that will enhance “virtual tourism” and let anyone, anywhere, actually see what an area looks like as if they were standing there. The applications in surveying and for transportation engineering are compelling, and may change entire professions.