3D reconstruction technique of pipe based on centerline matching

For the problem of low efficiency of 3D reconstruction of pipe in the industrial field, a 3D reconstruction method of pipe based on centerline matching is presented. First, the centerlines and edges of the pipe are extracted from pipe's gray-level images. According to the principle of stereo vision, non-uniform rational B-spline (NURBS) curve is chosen as a description tool and matching primitive. The spatial centerlines of the pipe are reconstructed based on the perspective projection invariance of NURBS curve, and the external diameter of the pipe is calculated through the extracted edges. Finally, the pipe's CAD model is reconstructed by 3D modeling technique. Compared with the existing methods, the proposed method has the advantages of high efficiency and simple operation. It is shown through experimental results that the time of 3D reconstruction is within 1 minute, the re-projection error is 0.284 pixel, the measurement error of end points is 0.242 mm, and the measurement error of external diameter is 0.158 mm.