Capturing heritage data with 3D laser scanners

The authors consider hand-held laser scanners, as a new photogrammetric tool for obtaining three-dimensional models of objects. The principle of their work and the newest optical systems based on various sensors measuring the depth of space are described in detail. The method of simultaneous navigation and mapping (SLAM) used for combining single scans into point cloud is outlined. The formulated tasks and methods for performing studies of the DotProduct (USA) hand-held laser scanner DPI?8X based on a test site survey are presented. The accuracy requirements for determining the coordinates of polygon points are given. The essence of the performed experimental research of the DPI?8X scanner is described, including scanning of a test object at various scanner distances, shooting a test polygon from various scanner positions and building point cloud, repeatedly shooting the same area of the polygon to check the stability of the scanner. The data on the assessment of accuracy and analysis of research results are given. Fields of applying hand-held laser scanners, their advantages and disadvantages are identified.

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LiDAR-Based Glass Detection for Improved Occupancy Grid Mapping

Sensors ◽

10.3390/s21072263 ◽

2021 ◽

Vol 21 (7) ◽

pp. 2263

Author(s):

Haileleol Tibebu ◽

Jamie Roche ◽

Varuna De Silva ◽

Ahmet Kondoz

Keyword(s):

Laser Scanner ◽

Point Clouds ◽

Light Detection And Ranging ◽

Test Results ◽

New Approach ◽

Occupancy Grid ◽

Laser Scanners ◽

Novel Method ◽

Occupancy Grid Mapping ◽

Cartesian Coordinate

Creating an accurate awareness of the environment using laser scanners is a major challenge in robotics and auto industries. LiDAR (light detection and ranging) is a powerful laser scanner that provides a detailed map of the environment. However, efficient and accurate mapping of the environment is yet to be obtained, as most modern environments contain glass, which is invisible to LiDAR. In this paper, a method to effectively detect and localise glass using LiDAR sensors is proposed. This new approach is based on the variation of range measurements between neighbouring point clouds, using a two-step filter. The first filter examines the change in the standard deviation of neighbouring clouds. The second filter uses a change in distance and intensity between neighbouring pules to refine the results from the first filter and estimate the glass profile width before updating the cartesian coordinate and range measurement by the instrument. Test results demonstrate the detection and localisation of glass and the elimination of errors caused by glass in occupancy grid maps. This novel method detects frameless glass from a long range and does not depend on intensity peak with an accuracy of 96.2%.

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A Complex for Monitoring Transport Infrastructure Facilities Based on Video Surveillance Cameras and Laser Scanners

Transportation Research Procedia ◽

10.1016/j.trpro.2021.02.130 ◽

2021 ◽

Vol 54 ◽

pp. 775-782

Author(s):

Dmitry Gura ◽

Ivan Markovskii ◽

Nafset Khusht ◽

Irina Rak ◽

Saida Pshidatok

Keyword(s):

Video Surveillance ◽

Transport Infrastructure ◽

Laser Scanners ◽

Surveillance Cameras

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Metric Accuracy Evaluation of Dense Matching Algorithms in Archeological Applications

Geoinformatics FCE CTU ◽

10.14311/gi.6.34 ◽

2011 ◽

Vol 6 ◽

pp. 275-282 ◽

Cited By ~ 2

Author(s):

C. Re ◽

S. Robson ◽

R. Roncella ◽

M Hess

Keyword(s):

Laser Scanner ◽

Medium Size ◽

Accuracy Evaluation ◽

Software Packages ◽

Dense Matching ◽

Laser Scanners ◽

Surface Models ◽

University College London ◽

Archaeological Artifacts ◽

Archaeological Objects

In the cultural heritage field the recording and documentation of small and medium size objects with very detailed Digital Surface Models (DSM) is readily possible by through the use of high resolution and high precision triangulation laser scanners. 3D surface recording of archaeological objects can be easily achieved in museums; however, this type of record can be quite expensive. In many cases photogrammetry can provide a viable alternative for the generation of DSMs. The photogrammetric procedure has some benefits with respect to laser survey. The research described in this paper sets out to verify the reconstruction accuracy of DSMs of some archaeological artifacts obtained by photogrammetric survey. The experimentation has been carried out on some objects preserved in the Petrie Museum of Egyptian Archaeology at University College London (UCL). DSMs produced by two photogrammetric software packages are compared with the digital 3D model obtained by a state of the art triangulation color laser scanner. Intercomparison between the generated DSM has allowed an evaluation of metric accuracy of the photogrammetric approach applied to archaeological documentation and of precision performances of the two software packages.

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Angular resolution of terrestrial laser scanners

The Photogrammetric Record ◽

10.1111/j.1477-9730.2006.00367.x ◽

2006 ◽

Vol 21 (114) ◽

pp. 141-160 ◽

Cited By ~ 89

Author(s):

Derek D. Lichti ◽

Sonam Jamtsho

Keyword(s):

Angular Resolution ◽

Laser Scanners

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Research on laser stripe characteristics and center extraction algorithm for desktop laser scanner

SN Applied Sciences ◽

10.1007/s42452-021-04309-w ◽

2021 ◽

Vol 3 (3) ◽

Author(s):

Xiaoquan Shi ◽

Yazhou Sun ◽

Haitao Liu ◽

Linqi Bai ◽

Chonghao Lin

Keyword(s):

Laser Scanner ◽

Bright Spot ◽

Distribution Characteristics ◽

Ambient Light ◽

Centroid Method ◽

Laser Stripe ◽

Wide Range ◽

Laser Scanners ◽

Extraction Algorithm ◽

Large Width

AbstractThis study presents laser stripe center extraction algorithm for desktop-level 3D laser scanners. The laser stripe center extraction accuracy is an important factor affecting 3D scanning result. Desktop-level devices should have adaptability of a wide range of scanning objects. In this paper, laser stripe energy distribution characteristics with different laser stripe width, ambient light, materials and colors are obtained by experiments. Experiment results show that waveforms of bright spot, low brightness stripe and stripe with large width are complex or easily disturbed, so the center extraction algorithm of them are studied. The extraction effects of extremum method, gradient method and gray centroid method under different conditions are compared. Based on traditional grayscale value, a weighted grayscale value is proposed to extract laser stripe center. Standard deviations of extracted pixel position and fitting pixel position are calculated by different method with different weighted grayscale value. For different conditions, especially for different ambient light intensity, weight matrix plays an important role to extraction result.

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