Real-time triangulation of point streams


Hand-held laser scanners are commonly used in industry for reverse engineering and quality measurements. In this process, it is difficult for the human operator to scan the target object completely and uniformly. Therefore, an interactive triangulation of the scanned points can assist the operator in this task. In this paper, we describe the technical and implementational details of our real-time triangulation approach for point streams, presented at the 17th International Meshing Roundtable. Our method computes a triangulation of the point stream generated by the laser scanner online, i.e., the data points are added to the triangulation as they are received from the scanner. Multiple scanned areas and areas with a higher point density result in a finer mesh and a higher accuracy. On the other hand, the vertex density adapts to the estimated surface curvature. To guide the operator, the resulting triangulation is rendered with a visualization of its uncertainty and the display of an optimal scanning direction.

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This work was supported by DFG IRTG 1131 “Visualization of large and unstructured data sets.” We also thank Faro Europe for lending out their “Laser ScanArm” and “Pfalzgalerie Kaiserslautern” and “Vereinigung Pfälzer Kunstfreunde (VKP)” for their generous support with the sculpture [19]. In particular, we thank Peter Salz for his help on the implementation of the visualizations of the optimal scanning direction.

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Correspondence to Klaus Denker.

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Denker, K., Lehner, B. & Umlauf, G. Real-time triangulation of point streams. Engineering with Computers 27, 67–80 (2011).

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  • Online triangulation
  • Point streams
  • 3d Laser scanner
  • Quality visualization
  • User assistance