What are the methods to obtain DEM data of airborne mode?

Aug 24, 2023

Airborne DEM data acquisition mainly includes aerial photogrammetry, airborne laser LiDAR, airborne laser sounding system and UAV.

1. Aerial photogrammetry method

Aerial photogrammetry is a method to reconstruct the three-dimensional model of earth surface and measure the three-dimensional space coordinates by using the stereo image taken by the large format digital aerial camera. At present, fully digital automated or interactive methods based on digital photogrammetric workstations are relatively mature and can be used to obtain high-precision and high-fidelity DEM.

2. Airborne laser LiDAR

Airborne LiDAR can obtain high density 3D position point cloud data on the ground, and DSM and DTM can be obtained simultaneously through multiple echo filtering, classification and modeling. It has been widely used in active fault identification, landslide monitoring, coastal zone vulnerability analysis and other fields.

3. Drones

Drones can be used to carry digital cameras, SAR, LiDAR and other equipment, especially suitable for small scale, low-cost projects (such as local erosion, sedimentation, urban planning, etc.) DEM acquisition.

The motion reconstruction technology developed in recent years and applied to structural geomorphology, forestry, agriculture, archaeology and other fields only requires a camera equipped with traditional aerial photogrammetry platform or UAV, kite, balloon, pole and other platforms to take overlapping photos of the image of the area of interest, and can generate high-precision and high-resolution DEM based on point cloud post-processing software.