TESTING ACCURACY OF HEIGHT USING A VARIETY OF GEODETIC DEVICES

2018 ◽  
Author(s):  
Aleksandre Lomtadze ◽  
Rūta Puzienė
Keyword(s):  
Laser Scanner ◽  
Measurement Methods ◽  
Electronic Timer ◽  
Accuracy Of Measurements ◽  
Testing Accuracy

In this paper we compare these three methods for testing accuracy of height using a variety of geodetic devices. Each method and device used allows for some precision results. This article examines the extent to which the accuracy of measurements is obtained theoretically, by choosing different measurement methods and different devices, obtained in practice, after measurements, i.e. how many heights measured by different devices will differ from each other. The study of measurements results from the chosen geodetic mark using different geodetic instruments was performed. The following devices are available for testing: GPNS Trimble 5800, Trimble M3 electronic timer, Leica Scan Station C10 laser scanner.

Use of Laser Scanner for Digital Surveying of the Sarnicli Inn and the Byzantine Cistern Underneath

2017 ◽  
pp. 227-254
Author(s):  
Gülhan Benli ◽  
Eylem Görmüş Ekizce
Keyword(s):  
Cultural Heritage ◽  
Protected Areas ◽  
Laser Scanning ◽  
Laser Scanner ◽  
3D Scanning ◽  
Measurement Methods ◽  
Advanced Technology ◽  
Laser Scanners ◽  
Close Range ◽  
Photogrammetric Measurement

Measurement methods including traditional measurement methods, topographic and photogrammetric measurement methods, measurements via laser scanning devices and aerial photogrammetric measurement methods obtained using model airplane or model helicopters are used in documentation of the cultural heritage and protected areas in our country. Although data obtained by Aerial Lidar technology accepted as advanced technology over the past decade, enables faster data comparing to others as data obtained by terrestrial laser scanners provide millimetre level accuracy close-range scanning methods are preferred in architectural facades scanning during the process of surveying of a single building. Inclusion process of a Byzantine cistern in Istanbul, Turkey, which was undiscovered for centuries, in our cultural heritage as well as surveying stages of the cistern along with the inn structure built over, using 3D scanning technology shall be described within this study.

scholarly journals Accuracy of laser-scanned models compared to plaster models and cone-beam computed tomography

2013 ◽  
Vol 84 (3) ◽  
pp. 443-450 ◽  
Author(s):  
Jooseong Kim ◽  
Giseon Heo ◽  
Manuel O. Lagravère
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
Laser Scanner ◽  
Cone Beam ◽  
Advantages And Disadvantages ◽  
Accuracy Of Measurements ◽  
Highly Correlated ◽  
Plaster Models

ABSTRACT Objective: To compare the accuracy of measurements obtained from the three-dimensional (3D) laser scans to those taken from the cone-beam computed tomography (CBCT) scans and those obtained from plaster models. Materials and Methods: Eighteen different measurements, encompassing mesiodistal width of teeth and both maxillary and mandibular arch length and width, were selected using various landmarks. CBCT scans and plaster models were prepared from 60 patients. Plaster models were scanned using the Ortho Insight 3D laser scanner, and the selected landmarks were measured using its software. CBCT scans were imported and analyzed using the Avizo software, and the 26 landmarks corresponding to the selected measurements were located and recorded. The plaster models were also measured using a digital caliper. Descriptive statistics and intraclass correlation coefficient (ICC) were used to analyze the data. Results: The ICC result showed that the values obtained by the three different methods were highly correlated in all measurements, all having correlations >0.808. When checking the differences between values and methods, the largest mean difference found was 0.59 mm ± 0.38 mm. Conclusions: In conclusion, plaster models, CBCT models, and laser-scanned models are three different diagnostic records, each with its own advantages and disadvantages. The present results showed that the laser-scanned models are highly accurate to plaster models and CBCT scans. This gives general clinicians an alternative to take into consideration the advantages of laser-scanned models over plaster models and CBCT reconstructions.

Use of Laser Scanner for Digital Surveying of the Sarnicli Inn and the Byzantine Cistern Underneath

2019 ◽  
pp. 275-303
Author(s):  
Gülhan Benli ◽  
Eylem Görmüş Ekizce
Keyword(s):  
Cultural Heritage ◽  
Protected Areas ◽  
Laser Scanning ◽  
Laser Scanner ◽  
3D Scanning ◽  
Measurement Methods ◽  
Advanced Technology ◽  
Laser Scanners ◽  
Close Range ◽  
Photogrammetric Measurement

Measurement methods including traditional measurement methods, topographic and photogrammetric measurement methods, measurements via laser scanning devices and aerial photogrammetric measurement methods obtained using model airplane or model helicopters are used in documentation of the cultural heritage and protected areas in our country. Although data obtained by Aerial Lidar technology accepted as advanced technology over the past decade, enables faster data comparing to others as data obtained by terrestrial laser scanners provide millimetre level accuracy close-range scanning methods are preferred in architectural facades scanning during the process of surveying of a single building. Inclusion process of a Byzantine cistern in Istanbul, Turkey, which was undiscovered for centuries, in our cultural heritage as well as surveying stages of the cistern along with the inn structure built over, using 3D scanning technology shall be described within this study.

Laser Scanners

2017 ◽  
pp. 108-145 ◽  
Author(s):  
Lars Lindner
Keyword(s):  
Laser Beam ◽  
Vision System ◽  
Laser Scanner ◽  
Image Sensors ◽  
Measurement Methods ◽  
Coordinate Measurement ◽  
Technical Vision ◽  
Laser Scanners ◽  
Engineering Institute

The presented book chapter provides an overview and detailed description about actual used laser scanner systems. It explains and compares the mainly used coordinate measurement methods, like Time-of-flight, Phasing and Triangulation and Imaging. A Technical Vision System, developed by the engineering institute at the Autonomous University Baja California (UABC) is presented. The mostly used mechanical principles to position a laser beam in a field of view are described and which mechanical actuators are applied. The reflected laser beam gets measured by light sensors or image sensors, which are explained and some principle measuring circuits are provided. The received measuring data gets post-processed by different algorithm or principles, which close the chapter.

scholarly journals SYMBIOSIS OF UAS PHOTOGRAMMETRY AND TLS FOR SURVEYING AND 3D MODELING OF CULTURAL HERITAGE MONUMENTS - A CASE STUDY ABOUT THE CATHEDRAL OF ST. NICHOLAS IN THE CITY OF GREIFSWALD

2015 ◽  
Vol XL-1/W4 ◽  
pp. 91-96 ◽  
Author(s):  
G. J. Grenzdörffer ◽  
M, Naumann ◽  
F. Niemeyer ◽  
A. Frank
Keyword(s):  
Cultural Heritage ◽  
3D Modeling ◽  
Laser Scanner ◽  
Measurement Methods ◽  
Terrestrial Laser Scanner ◽  
High Quality ◽  
Standard Deviations ◽  
The City

In this contribution the possibility to combine terrestrial laser scanner (TLS) measurements and UAS photogrammetry for the detailed description and high quality surveying of a cultural monument will be illustrated by the example of the Cathedral of St. Nicholas in the city of Greifswald. Due to the different nature of UAS photogrammetry and TLS walls and windows as well as portions of roofs are captured with a different level of completeness and accuracy. The average deviations of the test areas on the overlap between the two measurement methods ranges from 0.015 m to 0.033 m with standard deviations of 0.025 m to 0.088 m.

scholarly journals The influence of mining activities on the Church of St. Cross in Bytom-Miechowice

2018 ◽  
Vol 105 (1) ◽  
pp. 7-18
Author(s):  
Tomasz Lipecki ◽  
Hanna Ligarska ◽  
Małgorzata Zawadzka
Keyword(s):  
Spatial Analysis ◽  
Laser Scanning ◽  
Laser Scanner ◽  
Comprehensive Analysis ◽  
Measurement Methods ◽  
Mining Activities ◽  
Scanning Method ◽  
Current State ◽  
The Church ◽  
Geometrical State

Abstract The paper presents an analysis of the influence of multiannual coal exploitation on the church situated in Bytom–Miechowice. The objects has been monitored for many years by classic measurement methods as well as by the laser scanner. The measurements performed in 2015 allowed for a comprehensive analysis of the geometrical state of the construction. Laser scanning method enabled creating a model of the current state of the building and comparing with theoretical dimensions and dependents. The article focuses on the specific of conducting spatial analysis, which must take into account not only geometry of the construction, but also the kinematics of terrain deformations as well.

scholarly journals Reconstruction of Conifer Root Systems Mapped with Point Cloud Data Obtained by 3D Laser Scanning Compared with Manual Measurement

Forests ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1117
Author(s):  
Chikage Todo ◽  
Hidetoshi Ikeno ◽  
Keitaro Yamase ◽  
Toko Tanikawa ◽  
Mizue Ohashi ◽  
...  
Keyword(s):  
Root System ◽  
Point Cloud ◽  
Laser Scanner ◽  
Root Systems ◽  
Point Cloud Data ◽  
Manual Measurement ◽  
Cloud Data ◽  
Accuracy Of Measurements ◽  
Laser Scanners ◽  
Point Data

Three-dimensional (3D) root system architecture (RSA) is a predominant factor in anchorage failure in trees. Only a few studies have used 3D laser scanners to evaluate RSA, but they do not check the accuracy of measurements. 3D laser scanners can quickly obtain RSA data, but the data are collected as a point cloud with a large number of points representing surfaces. The point cloud data must be converted into a set of interconnected axes and segments to compute the root system traits. The purposes of this study were: (i) to propose a new method for easily obtaining root point data as 3D coordinates and root diameters from point cloud data acquired by 3D laser scanner measurement; and (ii) to compare the accuracy of the data from main roots with intensive manual measurement. We scanned the excavated root systems of two Pinus thunbergii Parl. trees using a 3D laser scanner and neuTube software, which was developed for reconstructing the neuronal structure, to convert the point cloud data into root point data for reconstructing RSA. The reconstruction and traits of the RSA calculated from point cloud data were similar in accuracy to intensive manual measurements. Roots larger than 7 mm in diameter were accurately measured by the 3D laser scanner measurement. In the proposed method, the root point data were connected as a frustum of cones, so the reconstructed RSAs were simpler than the 3D root surfaces. However, the frustum of cones still showed the main coarse root segments correctly. We concluded that the proposed method could be applied to reconstruct the RSA and calculate traits using point cloud data of the root system, on the condition that it was possible to model both the stump and ovality of root sections.

Large-scale Motion of Solar Filaments

2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll
Keyword(s):  
Magnetic Flux ◽  
Proper Motion ◽  
Time Scale ◽  
Large Scale ◽  
Accuracy Of Measurements ◽  
Solar Filaments ◽  
General Movement ◽  
Scale Motion ◽  
Velocity Scatter

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.

Kinematical and Dynamical CBED Pattern Models: Increasing the Accuracy of the Unit-Cell Parameter Measurements Based on CBED Patterns

1990 ◽  
Vol 48 (2) ◽  
pp. 540-541
Author(s):  
I.N. Yadhikov ◽  
S.K. Maksimov
Keyword(s):  
Reciprocal Lattice ◽  
Unit Cell ◽  
Reciprocal Lattice Vector ◽  
Unit Cell Parameters ◽  
Lattice Vector ◽  
Cell Parameters ◽  
Accuracy Of Measurements ◽  
The Difference ◽  
Image Position ◽  
Convergent Beam

Convergent beam electron diffraction (CBED) is widely used as a microanalysis tool. By the relative position of HOLZ-lines (Higher Order Laue Zone) in CBED-patterns one can determine the unit cell parameters with a high accuracy up to 0.1%. For this purpose, maps of HOLZ-lines are simulated with the help of a computer so that the best matching of maps with experimental CBED-pattern should be reached. In maps, HOLZ-lines are approximated, as a rule, by straight lines. The actual HOLZ-lines, however, are different from the straights. If we decrease accelerating voltage, the difference is increased and, thus, the accuracy of the unit cell parameters determination by the method becomes lower.To improve the accuracy of measurements it is necessary to give up the HOLZ-lines substitution by the straights. According to the kinematical theory a HOLZ-line is merely a fragment of ellipse arc described by the parametric equationwith arc corresponding to change of β parameter from -90° to +90°, wherevector, h - the distance between Laue zones, g - the value of the reciprocal lattice vector, g‖ - the value of the reciprocal lattice vector projection on zero Laue zone.

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