LiDAR is a distance-measuring and imaging technology that uses pulses of light from a laser beam utilizing the ultraviolet, visible or infrared portions of the electromagnetic spectrum.
LiDAR mapping technology uses measurements of reflected laser pulses to produce highly accurate maps and elevation models of terrain and buildings. LiDAR mapping payloads may be fitted to drones, UAVs (unmanned aerial vehicles), USVs (uncrewed surface vessels), UGVs (unmanned ground vehicles) and robots.
Drone LiDAR surveys are carried out with unmanned aircraft and gather data that can be used to create 3D digital terrain or elevation models. Depths of water features can also be measured using bathymetric LiDAR. Unmanned LiDAR systems offer significant time and cost savings over traditional manned mapping and surveying methods.
LiDAR technology has many applications and is especially ideal when high-accuracy measurements are required, or when the area under survey or inspection is dangerous or physically difficult to reach. Drone LiDAR mapping using UAVs provides many additional benefits, including reduced mission time and manpower requirements, and the ability to obtain quicker results by gathering all required data in a single pass.
Modern LiDAR scanners are capable of achieving a wide field of view (FOV) and offer 360 degree visibility and very high data rates. LiDAR mapping has been used in surveying, cartography, agriculture, forestry, meteorology, mining, environmental management, inspection of utility lines and transport networks, and many other fields.
Topographic LiDAR refers to the application of LiDAR scanning to land-based mapping. LiDAR terrain mapping is typically carried out using a near-infrared (NIR) laser to capture a high-density point cloud that can be used to generate high-precision 3D maps and models of the Earth’s surface.
UAV topographic LiDAR payloads may incorporate a GPS receiver and an INS (inertial navigation system), in order to ensure that the location of each data point captured is highly accurate. Data can also be run through LiDAR post-processing software to further improve precision and accuracy.
The accuracy of LiDAR mapping depends on the equipment used, the distance to the target, post-processing of the data and many other factors. It is possible to achieve sub-centimetre accuracy. Unmanned aerial lidar survey payloads can also be customised to include photogrammetry, hyperspectral and thermal imaging technology.