Drone-Based Laser Triangulation System for Geometry Measurement of Local Surface Defects

The regular inspection of structures, such as bridges or wind turbines, for surface damage is essential for condition assessment and planning maintenance tailored to specific needs. However, existing solutions always represent a compromise between measurement distance and resolution. The use of drone-based optical measurement systems offers the possibility of accurately capturing the geometry of local surface damage on hard-to-reach structures in the millimeter range. In this context, an existing laser triangulation system that measures area-wise through a single-shot method is intended to be optimized. The goal is to realize a drone-based measurement system demonstrator for the reconstruction of 3D surfaces with a depth resolution of < 1 mm. The beam shape and quality have a significant impact on achievable resolutions (lateral and axial). The main tasks include adapting the existing laser triangulation system, implementing image processing algorithms for the reconstruction of the 3D surface, and conducting theoretical and experimental investigations of the beam shape and quality concerning achievable resolution, SNR, and sensitivity.