LiDAR scanning is based on the registration of the direction and time of the laser beam, bouncing back and forth on the object. An unmanned aerial vehicle is equipped with a small-sized ultra-light LiDAR (laser scanner), that scans the terrain. The GPS receiver determines the position of the scanner, and knowing its rotation angles we get the absolute coordinates of each point in space.
As a result of the scanning process, we receive a super accurate three-dimensional map of points, which could be a digital elevation model or any object model. Hence, we analyze the point clouds and alter them into understandable indicators.