Search results for "numérisation"

Automatic production of three-dimensionnel models by 3D digitization

2012

The manual 3D digitization process is expensive since it requires a highly trained technician who decides about the different views needed to acquire the object model. The quality of the final result strongly depends, in addition to the complexity of the object shape, on the selected viewpoints and thus on the human expertise. Nowadays, the most developed digitization strategies in industry are based on a teaching approach in which a human operator manually determines one set of poses for the ranging device. The main drawback of this methodology is the influence of the operator's expertise. Moreover, this technique does not fulfill the high level requirement of industrial applications which…

3D digitization of transparent objects by polalization techniques in IR & by triangulation in UV

2011

Two non-conventional methods for the 3D digitization of transparent objects via non-contact measurement are reported in this thesis. 3D digitization is a well acknowledged technique for opaque objects and various commercial solutions based on different measurement approaches are available in the market offering different types of resolution at different prices. Since these techniques require a diffused or lambertian surface, their application to transparent surfaces fails. Indeed, rays reflected by the transparent surface are perturbed by diverse inter-reflections induced by the refractive properties of the object. Therefore, in industrial applications like quality control, the transparent …

Knowledge engineering and semantic formalism of symbolic relations. From medieval network to web 3.0

2020

A search has always been at the center of human concerns, the one of conditions and means to represent, to control well, and to communicate effectively with his environment. While technological advances and electronic gadgets such as smartphones, the Web, and online social networks currently allow addressing this concern, it has not always been the case. Our works in this thesis treat medieval documents considered as a medium of communication and as a model of the social network in the Middle Ages. These documents are called medieval illuminations. They were luxurious paintings used in that time to represent the environment and ideal world for elites such as prince, duke, etc. Those paintin…

"Introduction¨, Histoire documentaire du communisme,

2017

National audience

Trois algorithmes intelligents pour la numérisation 3D automatique d'objets inconnus

2013

National audience; Ce papier propose trois approches itératives et intelligentes de planification de vue pour la numérisation 3D d'objets sans connaissance a priori de leurs formes. La première méthode est une approche simple et naïve basée sur la génération d'un ensemble de points de vues par échantillonnage régulier de l'enveloppe englobante des données acquises. La deuxième méthode est basée sur une analyse de l'orientation des différentes parties acquises. La troisième méthode vise à explorer les parties de l'objet qui figurent dans la limite du champ de visibilité et est basée sur un couplage de la visibilité angulaire avec la visibilité réelle par lancer de rayons. Les résultats de nu…

Automation of Acquisition and Post-processing for 3D Digitalisation

2009

The automation of digitalisation is an indispensable step in the development of 3D measuring, in various fields :- in industry, to accelerate the procedures for control of parts,- in archaeology and biology, for the study of collections of several hundreds even thousand objects (for which the acquisition is for the moment impossible because of necessary time, and thus of the cost). In this thesis, we explain first the various existing systems of acquisition and positioning, by detailing the advantages and the inconveniences of every system. We present then the developed methodology to guide the operator in these choices as well as the tool set up to formalize this methodology. Then we will …

Histoire et mémoire du vin : enjeux économiques et patrimoniaux

2017

« La donnée et le périodique »

2022

Numérisation et données des périodiques britanniques

Integration of high resolution spatial and spectral data acquisition systems for monitoring purposes in cultural heritage applications

2013

The concern and interest of this PhD thesis is the registration of featureless 3D and multispectral datasets describing cultural heritage objects.In this context, there are few natural salient features between the complementary datasets, and the use of targets is generally proscribed.We thus develop a technique based on the photogrammetric tracking of the acquisition systems in use.A series of simulations was performed to evaluate the accuracy of our method in three configurations chosen to represent a variety of cultural heritage objects.These simulations show that we can achieve a spatial tracking accuracy of 0.020 mm and an angular accuracy of 0.100 mrad using four 5 Mpx cameras when dig…

3 D digitization of specular metallic surfaces by means of infrared imaging

2012

For the past twenty years, the need for three-dimensional digitization of manufactured objects has increased significantly and consequently, many experimental techniques and commercial solutions have been proposed. However, difficulties remain for the acquisition of optically non cooperative surfaces, such as transparent or specular ones. Since the working principle of conventional scanners is based on the acquisition of the diffuse part of the reflection, transparency and specular reflections may cause outliers. To address highly reflective metallic surfaces, we propose the extension of a non conventional technique that was originally dedicated to glass objects, called “Scanning from Heati…