A case study on the introduction of an advanced ship inspection method: Gross tonnage measurement 3D point clouds

This study examines the feasibility of gross tonnage (GT) measurement using 3D point cloud technology as a digital alternative to traditional manual methods. While ships over 24 m follow standardized regulations under the 1969 Tonnage Measurement Convention (TMC), those under 24 m are subject to diverse national rules, often based on simplified formulas. In this study, 3D point clouds were acquired using laser scanners for two Korean vessels—a government-owned ship over 24 m and a fishing vessel under 24 m. After post-processing, the enclosed volume was estimated using a convex hull algorithm and compared with GT values calculated under national standards. The point cloud-based method showed minimal variation, with a maximum difference of 0.30 % in volume and 0.23 TON in GT. These results indicate that 3D scanning provides a reliable and accurate alternative for GT measurement and offers potential for broader institutional adoption through standardized digital workflows.