Generating an accurate DTM for the preliminary design of infrastructures with UAS Lidar payloads

High-resolution Digital Terrain Models (DTM) are widely used in the preliminary design of infrastructures. The multi-echo technology of a Lidar payload allows penetrating the layers of vegetation to measure the ground points and model the terrain and the rocks underneath. Installing a Lidar payload in a multicopter drone is quick and easy in the field and makes it possible to run accurate mapping tasks in areas with difficult orography and relevant vegetation coverage. Scanfly

The project

 ND Aerial Service, a mapping company specializing in airborne surveys, choose Scanfly XT to collect accurate topographic details of a valley in the North of Italy, where their final customer intended to position a tunnel portal.

Purpose

The LiDAR surveys were performed to generate the 3D model of an area of about 75 hectares of the valley. In particular, the scope of the survey was to model a slope featuring a vertical granite wall about 70 m tall, and the valley floor. The requested accuracy was below 5 cm.

Results

The point cloud generated from the Scanfly acquisition using SmartProcessing Lidar was checked against the Ground Control Points measured in the area of interest, confirming the accuracy specifications of the device. The dual return and the 32 LiDAR channels allowed for the creation of the dense DTM and the orthophoto of the area requested as deliverables by the final customer.

The Scanfly advantages

 The deliverables extracted from the point clouds generated with Scanfly matched the accuracy specifications requested by the customer.