Construction of a High-Precision Underwater 3D Reconstruction System Based on Line Laser

This study presents a high-precision underwater 3D reconstruction system based on rotating laser scanning. The system adopts a modeling framework that combines air-based camera calibration with refraction compensation. A five-stage image preprocessing pipeline, followed by an adaptive locally weighted centroid (ALWC) algorithm, is employed to extract the laser stripe centerline with high accuracy. In addition, a synchronized feature extraction-based joint calibration method is introduced to simultaneously calibrate the light plane and the rotation axis. Resolution evaluation experiments demonstrate that the system achieves a spatial resolution of better than 0.6 mm in clear water at a distance of 1 m, and approximately 0.8 mm in turbid water conditions of 6 Nephelometric Turbidity Units (NTU), thereby verifying its reconstruction accuracy and robustness under varying water clarity.