Boundary recognition of ship planar components from point clouds based on trimmed delaunay triangulation

•An approach based on Delaunay triangulation is suggested for plane boundary recognition of ship small components from point clouds.•A triangle trimming algorithm for Delaunay triangulation is extract points located on concave and convex boundaries.•Non-boundary point simplification is applied to improve the efficiency of the proposed approach.•Specimen tests based on RGB-D camera are comparatively conducted to prove the effectiveness and robustness of the proposed method. A vision-based boundary detector is crucial for intelligent processing of ship planar components due to its automatically identifying workpiece edges. However, traditional methods suffer from many issues such as low accuracy and excessive detection errors for these workpieces with complex shape profiles. This paper proposes a trimmed Delaunay triangulation method (TDT) for recognizing boundary edges of planar workpieces from point clouds. It begins by distinguishing the difference of binary image pixel generated from point cloud to eliminate redundant points far away from plane boundary. Then, a triangulation trimming algorithm is developed to extract the edge points from the simplified points. Finally, complete plane boundary is reconstructed by a clustering-and-fitting method from the extracted edge points. Experimental results from multiple angles show that average absolute errors of straight edges and angles recognition are 1.29 mm and 1.04° respectively, which demonstrate that TDT has a high identification accuracy and robustness of plane boundary edge.