0000000000105249
AUTHOR
Alban Bajard
Numérisation 3D de surfaces métalliques spéculaires et diffuses par imagerie infrarouge active
National audience; Depuis plus de 20 ans, le besoin en numérisation 3D de pièces industrielles augmente considérablement. Par conséquent, un grand nombre de techniques expérimentales ont été proposées ainsi que quelques solutions commerciales. Cependant, des difficultés subsistent pour l'acquisition de surfaces optiquement noncoopératives, comme les surfaces transparentes et/ou spéculaires. En effet, la transmission, réfraction ou réflexion spéculaire de la lumière va à l'encontre du fonctionnement des systèmes conventionnels d'acquisition 3D, qui repose sur l'aspect diffus de la réflexion. Un moyen de contourner ce problème est le dépôt d'une couche de poudre matifiante afin de rendre la s…
Scanning From Heating : extension pour la numérisation 3D de surfaces métalliques spéculaires
National audience; En raison des difficultés liées à la réflexion spéculaire de certaines surfaces, peu de méthodes répétables ont été proposées pour mesurer la forme en trois dimensions des objets métalliques polis. Nous présentons l'application sur ce type de matériau d'une nouvelle approche appelée " Scanning From Heating ". Cette méthode a été initialement développée pour la numérisation 3D d'objets transparents. Du fait des nombreuses différences de propriétés physiques entre métaux et diélectriques, le principe de fonctionnement de la méthode SFH doit être modifié. Une simulation des échanges thermique grâce à un logiciel de calcul par éléments finis a permis de déterminer comment ada…
Application du Scanning From Heating à la numérisation 3D de surfaces métalliques spéculaires
Because of the difficulty of dealing with specularity of several surfaces, few methods have been proposed to measure three-dimensional shapes of specular metallic objects. In this paper we present an application on this kind of material of an approach called "Scanning From Heating". This approach has been developed initially for 3D reconstruction of transparent objects. This article presents an application of the working principle of SFH method on material with high thermal conductivity and low absorptivity.
3D shape extraction of internal and external surfaces of glass objects
Three-dimensional (3D) digitization of manufactured objects has been investigated for several years and consequently, many techniques have been proposed. Even if some techniques have been successfully commercialized, most of them assume a diffuse or near diffuse reflectance of the object’s surface, and difficulties remain for the acquisition of “optically non cooperative” surfaces, such as transparent or specular ones. To address such surfaces, we propose a non conventional technique, called “Scanning from Heating” (SfH). In contrast to classical active triangulation techniques that acquire the reflection of visible light, we measure the thermal emission of the heated surface. The aim of th…
Estimation de surface de Bézier à partir d'images de lumière structurée dans une optique de compression
National audience; Compression of 3D datas has become a topic of increasing importance over the evolution of scanners. With evolution of technologies, the commercial scanners give more and more data points, which can lead to difficulties in transmission or storage. In most cases, the acquisition does not take into account the final use of the data. While in many cases, this would limit the number of points. In this paper, we propose an approach which simplifies the scatterplot for industrial purposes using Bezier surfaces.
3 D digitization of specular metallic surfaces by means of infrared imaging
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…
3D Scanning of specular and diffuse metallic surfaces using an infrared technique
International audience; For the past two decades, the need for 3D Scanning of industrial objects has increased significantly. Therefore, 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 surfaces. To address highly reflective metallic surfaces, we propose the extension of a technique that was originally dedicated to glass objects. In contrast to conventional active triangulation techniques that measure the reflection of visible radiation, we measure the thermal emission of a surface, which is locally heated by a laser source. Considering the thermop…