Three-dimensional (3D) non-contact optical methods for surface inspection are of significant interest to many industrial sectors. Many aspects of manufacturing processes have become fully automated resulting in high production volumes. However, this is not necessarily the case for surface defect inspection. Existing human visual analysis of surface defects is qualitative and subject to varying interpretation. Automated 3D non-contact analysis should provide a robust and systematic quantitative approach. However, different 3D optical measurement technologies use different physical principles, interact with surfaces and defects in diverse ways, leading to variation in measurement data. Instrument s native software processing of the data may be non-traceable in nature, leading to significant uncertainty about data quantisation. Sub-millimetric level surface defect artefacts have been created using Rockwell and Vickers hardness testing equipment on various substrates. Four different non-contact surface measurement instruments (Alicona InfiniteFocus G4, Zygo NewView 5000, GFM MikroCAD Lite and Heliotis H3) have been utilized to measure different defect artefacts. The four different 3D optical instruments are evaluated by calibrated step-height created using slipgauges and reference defect artefacts. The experimental results are compared to select the most suitable instrument capable of measuring surface defects in robust manner. This research has identified a need for an automatic tool to quantify surface defect and thus a mathematical solution has been implemented for automatic defect detection and quantification (depth, area and volume) in 3D. A simulated defect softgauge with a known geometry has been developed in order to verify the implemented algorithm and provide mathematical traceability. The implemented algorithm has been identified as a traceable, highly repeatable, and high speed solution to quantify surface defect in 3D. Various industrial components with suspicious features and solder joints on PCB are measured and quantified in order to demonstrate applicability.

In this thesis a new three–dimensional (3D) vector radiative transfer model, the Solver for Polarized Atmospheric Radiative Transfer Applications (SPARTA) is introduced, validated against benchmark results, and applied to scientific problems. SPARTA employs the statistical forward Monte Carlo technique for efficient column–response pixel–based radiance calculations comprising polarization for 3D inhomogeneous cloudless and cloudy atmospheres. By means of SPARTA, two scientific issues in the field of radiative transfer are investigated. A sensitivity study has been conducted to illustrate the errors introduced by neglecting the effects of polarization in radiation simulations. Two atmospheric scenarios have been considered: a pure one–dimensional (1D) Rayleigh atmosphere and two–dimensional (2D) realistic inhomogeneous dust fields. In case of a purely molecular atmosphere, these errors strongly depend on molecular anisotropy, isotropic reflection, and more importantly, on single scattering albedo and optical thickness (saturation occurs for τ close to 1). Overall errors in the reflected field range up to about 10.5%. On the other hand, for rather high optical thickness, the bias induced by ignoring polarization for realistic inhomogeneous atmospheres is negligible (less than 1%). In addition, solar radiative transfer simulations for LIDAR–measured fields of optical properties of Saharan dust have been performed in order to quantify the effects induced by neglecting the horizontal photon transport and internal inhomogeneities (3D radiative effects) in radiance simulations including polarization. Results are presented for two exemplary mineral dust fields constructed from LIDAR observations. For each case, three radiative calculations are investigated: a 1D calculation according to the plane–parallel (1D mode); an Independent Pixel Approximation (IPA mode); and the 2D mode. The differences in domain–averaged normalized radiances of reflection and transmission are insignificant between the 1D or IPA and 2D calculation modes. However, local differences were observed since extinction is hinge on horizontal spatial variability. In the areas with large spatial variability in optical thickness, the radiance fields of the 2D mode differ about ±20% for the first and second Stokes elements (I, Q) from the fields of the 1D mode. This work points to a brand–new field: the quantification of the sensitivity of polarization to 3D radiative effects.

Le renouveau actuel du vocabulaire formel dans l'univers des architectures dites « non standards » s'appuie largement sur l'utilisation de modeleurs tridimensionnels. Dans cette démarche de conception, la stratégie de modélisation d'objets relève moins de l'utilisation directe de la géométrie que de la formalisation d'une idée. En effet, le travail de recherche morphologique, de la forme idée à la forme visée, nécessite de nombreux ajustements incompatibles avec une démarche linéaire de modélisation géométrique. Nous émettons l'hypothèse que la genèse des formes résulte d'opérations successives de transformation de forme fondées sur des objectifs sémantiques et guidées par une ou plusieurs images mentales. Ce cheminement se fait par des variations importantes entre différents états de la forme et par de nombreux ajustements de cette forme. Pour répondre à ce processus itératif nous proposons une approche paramétrique de la modélisation qui s'appuie sur des modificateurs de forme de haut niveau. Nous nommons opérateurs morphologiques ces outils d'action sur la forme qui permettent à partir d'une fonction de transformation morphologique (bomber, torsader, plisser...) de trouver par différentes solutions alternatives et par ajustement une forme satisfaisante. Notre travail aborde plus spécifiquement les opérateurs plier, plisser, froisser.

Cette thèse relève de l'indexation et de la représentation par le contenu des données multimédias, dans le contexte spécifique de la normalisationinternationale de l'image et notamment dans le cadre du processus de standardisation MPEG-7.<br /><br />Nous proposons tout d'abord de nouvelles mesures de similarité pour les descriptions de mouvement par modèles paramétriques 2D, fondées sur une famille de fonctions distance entre les champs de vitesses. Les problèmes d'optimisation en temps de calcul, d'alignement spatio-temporel et de pondération des composantes translationnelle et homogène de mouvement sont analysés et une solution mathématique proposée, mise en oeuvre et évaluée objectivement sur les bases de test naturelle et synthétique avec vérité terrain, que nous avons constituées et qui ont été retenues pour l'évaluation des descripteurs de mouvement MPEG-7.<br /><br />Deux descripteurs de forme pour indexer des modèles 3D maillés sont ensuite proposés. Partant des propriétés d'invariance géométrique et topologique que doit satisfaire naturellement un descripteur de forme d'objet 3D maillé, nous avons tout d'abord défini le spectre de forme 3D, que nous avons proposé et promu dans le standard MPEG-7. Celui-ci exploite uniquement la structure géométrique locale d'une surface 3D, fournit une représentation très compacte, mais présente une grande sensibilité aux descriptions topologiques des maillages. En considérant la transformée de Hough 3D d'un maillage, nous avons ensuite construit le descripteur de Hough 3D optimisé, intrinsèquement invariant aux changements de connexité, rendu indépendant aux transformations géométriques et optimisé en terme de compacité de représentation, via une partition invariante aux changements de repère canonique de la sphère unité.<br /><br />Enfin, nous proposons une plate-forme d'indexation compatible MPEG-7, intégrant des outils d'annotation, de navigation, de visualisation et de requêtes par similarité, et supportant des applications comme l'archivage vidéo, la vidéo cliquable ou l'indexation MPEG-7 de la langue des signes française. L'ensemble logiciel ainsi réalisé démontre pour la première fois en grandeur réelle, pour les applications d'indexation multimédia considérées, le caractère effectivement opérationnel des schémas de description génériques, normalisés MPEG7.

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This dissertation describes the development of an assist-device aimed to deliver 3D graphic information to the visually impaired people. A human-in-loop approach was used to analyze whether a virtual 3D shape can be transferred correctly to the human users.The proposed device in this dissertation consists of two major parts: (a) A system of position sensors for real time localization based on magnetization, and (b) A single vibratory actuator working at varied frequencies based on its real time location. The error bound of the position measurement was tested to be 2 mm, which defined the machine resolution of the shape display. In order to realize the refresh rate of the localization that can follow user's scanning speed, the parallel data processing sequences for computer and microcontroller were designed. Additionally, vibratory electromagnetic (EM) actuators were discussed based on eddy current and permanent magnet methods. The simulation study showed that eddy current method was not applicable for millimeter size coil. Accordingly, the permanent magnet method was developed and the force detection threshold of human tactile perceptions was studied.Virtual shape perception experiments were made with participation of 3 volunteers who were not aware of the 3D shape information prior to the tests. Based on the four sets of shape tests, we conclude that the majority of the shape information is able to be delivered to users by using the proposed device. Difficulties for perceiving the local sharp profile e.g. thin plates and large curvature in small shapes may be better addressed by multiple actuators simultaneously providing shape information in the local boundary detection.The major contribution of this dissertation is the 3D shape display implemented by a miniature and low cost device. The developed device utilizes both passive stimulation and active search so that a commonly used large scale actuators matrix based on mere active touch method is avoided. The studies on the required force/energy input from the actuator showed that EM actuators can be miniaturized to millimeter scale without sacrificing the ability to induce tactile stimulation. Additional uniqueness of the proposed system is the ability to present hollow features, which is impossible to display by the existing devices.