Datum Feature Extraction and Deformation Analysis Method Based on Normal Vector of Point Cloud

Abstract

ABSTRACT:In order to solve the problem lacking applicable analysis method in the application of three-dimensional laser scanning technology to the field of deformation monitoring, an efficient method extracting datum feature and analysing deformation based on normal vector of point cloud was proposed. Firstly, the kd-tree is used to establish the topological relation. Datum points are detected by tracking the normal vector of point cloud determined by the normal vector of local planar. Then, the cubic B-spline curve fitting is performed on the datum points. Finally, datum elevation and the inclination angle of the radial point are calculated according to the fitted curve and then the deformation information was analyzed. The proposed approach was verified on real large-scale tank data set captured with terrestrial laser scanner in a chemical plant. The results show that the method could obtain the entire information of the monitor object quickly and comprehensively, and reflect accurately the datum feature deformation.

A Point Cloud-Based Feature Recognition and Path Planning Method

“…Khan et al [10] used the depth vision sensor to pick up the datum of the workpiece to be inspected, and based on this, the ultrasonic inspection path is planned to realize the guidance of automatic ultrasonic inspection, and the image acquisition method produces a UT tool path with an accuracy of 0.43 mm. Sun et al [11] calculated the local plane normal vector determined by the point cloud method, and then fitted the reference point with B-spline curve equation, and finally, the elevation of the reference surface and the inclination angle of the radial point were calculated according to the fitted curve equation, so as to obtain the position and normal characteristics of the key points of the point cloud. Yang et al [12] propose a novel 3-D path extraction method of weld seams based on a stereo-structured light sensor, which could be well adapt to different types of welds and different groove sizes.…”