What is Lidar scanning?
Sometimes called “3D laser scanning,” Lidar is an acronym that stands for either “Light and Radar,” or “Laser Imagining Detection and Ranging,” depending on who you ask. Lidar is the three-dimensional scanning of a space or object, and is currently used in everything from mapping out massive facilities and cities to creating virtual 3D environments for the purposes of video games, mapping road systems in driver-less cars, geographic landscape mapping, underwater environmental mapping, and much more.
Bearing similarities to modern radar and sonar techniques, Lidar utilizes a pulsing laser, in place of sound or radio waves, to calculate distances, measuring the distance between an object and the laser scanner, measurements that are then placed into a 3D visualization known simply as the “point cloud.”
Whereas a photograph plots out a two-dimensional picture, and plotting out a three-dimensional environment via photography involves piecing together many different photographs taken at a myriad of angles and locations, Lidar plots millions of measurements in all directions simultaneously, mapping out a three-dimensional model of the environment with ease.
Lidar mapping, then, is georeferencing various point clouds to create a three-dimensional map of a much larger area than that of a single point cloud’s range capabilities, be it a large production facility or even an entire city.
Lidar scanning is significantly more efficient than, and most often preferable to, photogrammetry due to Lidar’s ability to “sift” through problem areas of measurement and still accurately create point clouds without faulty readings due to changes in elevation, poorly lit environments, narrow/problematic objects, etc.
Working within or outside of a given structure, we can use Lidar scanning to produce a three-dimensional map/model that can provide insight into geospatial measurements, structural integrity and surface degradation, and volumetric changes in voids or stockpiles.