Friday, February 12, 2010

Neither snow nor rain nor heat nor gloom of night...

With the recent snow storms impacting the country, I thought of no better topic than a discussion of weather and Mobile LiDAR.  It is relatively easy to work around localized weather events when utilizing a vehicle as opposed to an airplane or helicopter.  But sometimes, it's absolutely necessary to work in such conditions.

As discussed in earlier posts, LiDAR is an active sensor which uses a laser to measure distance to an object (same premise as total stations - traditional surveying instrument).  Therefore, our system can operate day or night and in virtually every weather condition.  We have several examples of night collections (Downtown Norfolk and I-85/285 in Atlanta), rain conditions (The Narrows - State College, PA) and now snow as shown below.

The image above was captured at our Beaver, PA office during snow flurries.  The image is colored by height to show all the snow in the scan (red dusting of points).  While the image below illustrates the same collection with the snow "cleaned" from the scan.  There are several different ways to accomplish this. But, it simply boils down to the intensity of the reflected light from the snow flakes and the elevation of those points.  Rain and snow each pose various processing challenges, but when you need information, sometimes it takes a little extra effort.

What is Mobile LiDAR?

Mobile LiDAR (Light Detection and Ranging) systems are comprised of vehicle-mounted lasers, cameras and GPS/INS navigation systems to capture highly-detailed and accurate three-dimensional (3D) topographic information for surveying and engineering applications. Michael Baker International became an early adopter of Mobile LiDAR technology by acquiring our first system in 2009, with further expansions in 2014 and 2015 that increased our fleet to four (4) Optech Lynx SG1 Mobile LiDAR systems. Over that period our systems have completed more than 300 projects throughout 29 different U.S. States (and multiple countries), and encompassing hundreds of thousands of miles. Our project portfolio includes applications in roadway design, 3D modeling, railroad corridors, signaled intersections, utility infrastructure, asset management, pavement condition assessment and airport infrastructure.