3D reconstruction of concrete defects using optical laser triangulation and modified spacetime analysis

Automated investigation of concrete defects has attracted attention with well-developed computer vision techniques. However, most studies in defect reconstruction mainly focus on identifying and measuring defects on a two-dimensional surface. Few progresses have been made to explore the 3D reconstruction of concrete defects. This study describes an affordable optical laser triangulation system fusing a linear laser ray generator and a sports camera to reconstruct the concrete defects. The proposed system adopts a modified spacetime analysis approach to solve two critical imaging errors in typical laser triangulation approaches. By comparing the outputs of the proposed system and two typical laser triangulation approaches, the results show that the proposed system can eliminate the imaging errors and generate 3D reconstruction models of concrete defects with acceptable accuracy.