IMEKO Event Proceedings

Page 4 of 855 Results 31 - 40 of 8545

Yu. V. Chugui, E. S. Senchenko

The peculiarities of 3D objects image formation with clear shadow projection under their illumination by partially coherent and perfectly incoherent light based on the constructive theory of 3D objects formation are investigated. Threshold algorithms for determining the position of 3D object geometric boundary, taking into account its thickness, the light source angular size and the projection system angular aperture are developed. These algorithms are based on the application of true (calculated) threshold or standard one using the corrective component for threshold. The cases of weak and strong 3D object volumetricity for partially coherent and incoherent illumination are studied. The analytical equations for these algorithms are given. It has been shown that their use can significantly improve the measurement accuracy of extended objects.

Roberto Cesareo, Stefano Ridolfi, Antonio Brunetti, Ricardo T. Lopes, Giovanni E. Gigante
3D Imaging of Paintings by Scanning with a Portable EDXRF-Device

3D map of chemical elements distribution from energy dispersive X-ray fluorescence (EDXRF) analysis would be a perfect conclusion to study in detail any type of artifact. This map can be easily achieved by using synchrotron light as source of radiation, and micro-optics both at the source and at the detector. In such a manner a micro-voxel is irradiated and detected, which can be at any depth with respect to the surface of the artifact. This method is effective but needs a synchrotron; therefore its use in archaeometry is greatly limited. An alternative method is proposed in the present paper, which uses the altered Kα/Kβ or Lα/Lβ-ratios to localize the chemical elements. This method employs a portable EDXRF-device, characterized by a small size X-ray tube and a Si-drift detector. Several examples are described.

Andrzej Masłowski, Janusz Będkowski, Paweł Musialik, Karol Majek

This paper presents the gathering, processing and presenting 3D data for use in Advanced Robotics Applications like Search and Rescue operations. The data are gathered by unmanned ground platforms, in the form of 3D point clouds via laser scanning systems. The clouds are matched and transformed into a consistent, highly accurate 3D model. The paper describes the pipeline for such matching based on Iterative Closest Point algorithm supported by loop closing done with LUM method. The pipeline was implemented for parallel computation with NVIDIA CUDA, which leads to higher matching accuracy and lower computation time.

Tomasz Koszmider, Krzysztof Strzecha

New 3D medical images reconstruction algorithm is presented in this paper. It concerns utilization of digital processing and analysis of Computed Tomography images in process of 3D lungs reconstruction.

Kazuhiro Enami, Tatuya Kume, Yasuo Higashi, Kenji Ueno

We strive to develop a 3D coordinate measuring machine, which can measure the inner shape of a cavity with a complex shape. Currently, the ILC (International Linear Collider) project is progressing through international collaboration. The major goal of ILC is to produce and investigate Higgs bosons. ILC consists of two linear accelerators facing each other, and will hurl some 10 billion electrons and positrons toward each other at nearly the speed of light. The cavity is an important component to accelerate particles to near light speed. A cavity’s inner 3D shape influences the accelerating performance. Therefore, it is important to measure the inner 3D shape of a cavity. However, it is difficult to measure the inner shape of cavities with complex shapes like a bellows. We are developing a highly accurate, inner shape measuring machine using triangulation and a measuring method.

Yuri Chugui, Sergei Plotnikov, Anatoly Potashnikov, Alexander Verkhogliad

The novel results of the R & D activity of TDI SIE SB RAS in the field of the optical measuring technologies, as well as laser technologies for solving safety problems are presented. To measure the rocks stress and to prevent the mountain impact, as well as for basic investigations, a set of optical-electronic deformers and systems was developed and produced. For permanent noncontact bearing position inspection of oil-drilling platforms on Sakhalin coast (Russia) we have developed optical-electronic method and system SAKHALIN. Multifunctional laser technological system LSP-2000 equipped by two Nd-YAG lasers was developed for cutting, welding and surface micro profiling with ablation process (working range of 3 x 2 x 0.6 m³, positioning error less than 10 mkm). Results of development and testing the specialized high productive laser measuring machine, based on structured illumination, for 3D inspection of grid spacers for Russian nuclear reactors with micron resolution are presented. Using high-speed laser noncontact method on the base of triangulation position sensors, TDI SIE has developed and produced automatic laser diagnostic system COMPLEX for inspection of geometric parameters of wheel pairs (train speed up to 60 km/hr.), which is used successfully on Russian railways.

Efstratia Chatzi, Stamatis Chatzistamatis, Nikolaos Soulakellis, Nikolaos Zouros, Christos-Nikolaos Anagnostopoulos
3D Modelling of Petrified Trees: Laser Scanning vs Photogrammetry

In this paper, a methodology for the photogrammetric and laser scan survey of tree fossils of the Petrified Forest on Lesvos island in Greece, is proposed.The Petrified Forest is of particular interest since it is one of the rarest monuments of geological heritage worldwide and it was formed from the fossilized remains of plants. During this study, photogrammetric and laser scanning data by the tree fossils have been gathered, processed and modelled in 3D, and a comparison of the two techniques is taking place. Finally, the most suitable technique for the 3D modelling of objects such as the petrified trees is proposed.

Francesca Ronco
3D modelling trough planar slides, from digital to physical. Experiments on Palazzo Mazzonis atrium in Turin

In recent decades, 3D acquisition has become one of the standard methods of documenting Cultural Heritage. At the same time digital fabrication has seen a recent massive diffusion for several applications, not least the field of Cultural Heritage, being used for study, analysis, conservation or access in museum exhibitions. The paper proposes a workflow, that starts from digital survey and modelling, aims to realize a physical model of the atrium Palazzo Mazzonis, an high-representation building, today converted in the Museum of Oriental Art (MAO). The method is grounded on the use of planar sections and of the contours of intersection of planes with the 3D digital model, for creating shape abstractions. The ModLab Arch and the ModLab Design of the Department of Architecture and Design at Politecnico di Torino are equipped with laser cut and CNC milling machines that will allow to continue with the experimentations here proposed.

Mauro Lo Brutto, Maria Grazia Spera
3D mosaics survey: analysis of photogrammetric/computer vision approach in a metrological context

The goal of the paper is evaluate photogrammetric/computer vision approach in a metrological context for 3D mosaics survey. The aim of the mosaics survey is the production of a full-scale representation (scale 1:1) useful for the documentation and for the restoration processes. In order to evaluate the optimal photogrammetric/computer vision workflow in this work three different surveys have been done for three mosaics with different size and location. Two of these are stored at Regional Archaeological Museum “Antonino Salinas” in Palermo (Italy) and the other one is stored at Regional Archaeological Museum “Baglio Anselmi” in Marsala (Italy). The research has allowed to show the potentiality and the issues of photogrammetric/computer vision approach for the 3D mosaic documentation.

S. N. Makarov, S. V. Plotnikov, E. V. Sysoev, A. G. Verkhogliad, P. S. Zav’yalov, Yu. V. Chugui, A. V. Latyshev, E. S. Senchenko

Solving many actual safety problems in science, atomic, optics-mechanical and railway industry takes 3D optical measuring technologies with micro-/ nanometer resolution and productivity from 100 to 105 meas./s. The novel results of the R & D activity of TDI SIE SB RAS in this field are presented.

Page 4 of 855 Results 31 - 40 of 8545