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Construction Object Identification from LADAR Scans: An Experimental Study Using I-Beams



David E. Gilsinn, Geraldine S. Cheok, Christoph J. Witzgall, Alan M. Lytle


Laser Scanning devices (LADAR for Laser Detection and Ranging) are used in construction projects to capture as-built data. They can rapidly generate large unstructured point clouds. This study describes an experiment in which an I-beam on a concrete floor surface is scanned, and the resulting point cloud data used to calculate its pose. Two approaches for segmenting potential target objects are described. Principal axis analysis is used to determine the pose of the I-beam. Bounding boxes are then formed around it and compared to an ideal bounding box generated from the known geometric specifications of the I-beam of interest. A separate laser-based site measurement system (SMS) was used to measure points on the I-beams to form reference data for estimating the closeness of fit of computed pose of the I-beam to measured pose of the I-beam. Three spheres were used as a means of registering the scan and SMS axes.
NIST Interagency/Internal Report (NISTIR) - 7286
Report Number


binning, bounding boxes, irregular networks, LADAR, object identification, pose, principal axes, triangulated network


Gilsinn, D. , Cheok, G. , Witzgall, C. and Lytle, A. (2005), Construction Object Identification from LADAR Scans: An Experimental Study Using I-Beams, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], (Accessed June 17, 2024)


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Created December 15, 2005, Updated February 19, 2017