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The scope of this thesis is to investigate and to develop a zoom lens videotheodolite system, which is formed by a zoom lens CCD camera, a motorised theodolite and a computer with the developed system software. A novel automatic calibration procedure is developed for the zoom lens CCD video-theodolite system. This method is suitable for the efficient calibration of any other video-theodolite system used in fieldwork. A novel image edge detection algorithm is developed. The maximum directional edge detection algorithm depends on the maximum directional gradient to judge the edges in an image. A novel line detection algorithm based on the Hough lines transform was developed for the applications of the video-theodolite system. This new algorithm can obtain not only the line parameters of r and 9 but also the data of the two terminal image points of the detected line. A novel method of constructing panoramic images from sequential images is developed based on the zoom lens video-theodolite system. It is effectively applied in the system to generate a panorama of a scene. A novel image matching algorithm is developed. The line features are matched with the constraint of epipolar lines. Through an experiment to match real world buildings, it is shown that the novel stereo matching algorithm is robust and effective. Another novel image matching algorithm is also developed. This algorithm is used to automatically measure the image displacement between the stereo images for the video-theodolite system. The accuracy of the zoom lens video-theodolite system is evaluated by three experiments. The measuring accuracy of this system can be within 0.09 pixels. The software of this system based on PC system is developed. It has a standard MFC windows interface with menu controls. This system software includes the control functions, measuring functions and image processing functions for the zoom lens video-theodolite system.

Refineries, the chemical industry, airports etc. have an existing stock of thousands of storage tanks, the majority of which were manufactured in the sixties. Depending on the field of industry they are used in, these tanks contain environmentally harmful fluids such as gasoline or petroleum oil in the petrochemical industry or acids in the chemical industry. Other than in newly constructed tanks, there are few possibilities in preventive leak detection in older tank constructions, as the bottom plate is in direct contact to the ground. Hidden corrosion in this structural element has caused a series of catastrophic petroleum spills in the past. In response to these spills, guidelines which specify how and when to inspect tanks have been established globally to guarantee their structural integrity. To allow the inspection of the tank's bottom plate in particular, using state of the art techniques and equipment, the tanks are taken out of service and prepared for the inspection. This preparation process requires draining, washing, degassing and ventilating the tank which is a very polluting, time consuming and expensive process. A review of existing approaches has shown that automated inspection systems where a crawler carries the inspection probes, while the tank remains filled, can circumvent the need for the preparation process. However, there are some serious limitations to such systems as the crawlers used are in direct contact with the tank's structure, where obstacles inside the tanks present a problem. To make such remotely operated vehicular systems more flexible and reliable, this study investigates the fundamental requirements and replaces the crawler with a remotely operated submersible. The critical review of currently available ROVs showed that it would be difficult to procure such a vehicle and so it was decided to develop a new ROV, where aspects of operational environment (use in different petrochemical fluids), high lateral stability as well as advantageous design with respect to the subsequent controller design have been taken into account. It has been shown that this design strategy led to a vehicle where linear controller design strategies could be applied. An analysis of its suitability for use in different petrochemical fluids is provided by a detailed study of the materials that have been used and the flexibility to adjust its buoyancy which has been built in. The lateral stability of the vehicle which is a prerequisite to performing the desired plate thickness measurement is demonstrated and the reliability and robustness of the control system that was employed is also considered. A final field experiment has shown the reliable interaction of the system components and that the inspection system provides a useful and desirable capability for use under field conditions. Finally, an analysis of the system's performance has also shown its economic viability.

Dans ce travail, les structures et les propriétés de plusieurs nanocomposites à base de Polyaniline sont étudiées avec le double objectif de réaliser un capteur d’ammoniac à très faible seuil de détection et une structure de blindage électromagnétique légère. Les aspects relatifs à la structure de bande, le dopage, le transport électronique et les phénomènes de percolation sont abordés. Ensuite, l’élaboration des composites se fait par le dopage de la PAni par l’acide camphre-sulfonique (CSA), qui permet la protonation de la PAni sous sa forme isolante (émeraldine base), avec un rapport molaire variant de 5% à 50%. Cependant, sous sa forme dopée (sel d’émeraldine), la PAni possède des propriétés mécaniques incompatibles avec les applications envisagées il est donc indispensable de réaliser des mélanges avec des thermoplastiques pour associer les propriétés électriques du polymère intrinsèquement conducteur aux propriétés mécaniques du thermoplastique. La conception du capteur d’ammoniac à été faite en plusieurs étapes: nous avons particulièrement étudié l’influence de la nature de la matrice hôte et l’effet du taux de dopage sur les caractéristiques métrologiques des capteurs. Le choix de la matrice ainsi que la stœchiométrie entre PAni et acide impactent directement le seuil de détection et l’amplitude de la réponse du capteur. Les résultats obtenus dans cette première partie du travail montrent qu’il est possible de détecter des teneurs d’ammoniac de l’ordre de 10 ppb en utilisant des composites à base de PAni dopée CSA avec un rapport molaire de 25%, et dispersée dans une matrice Polyuréthane (Pu). Dans la deuxième partie de ce travail, nous avons développé des matériaux hybrides multicouches, en incluant des nanoparticules magnétiques dans les composites conducteurs à base de PAni. L’optimisation des propriétés électroniques du matériau a permis de concevoir une structure bicouche qui répond aux besoins industriels (efficacité de blindage (SE) > 40 dB) et militaires (SE > 80 dB) de blindage électromagnétique. Les épaisseurs totales qui ont été déterminées sont de 530µm pour SE>40dB et 870µm pour SE>80dB. Les structures réalisées, sont également capables d’absorber une grande partie des ondes incidentes, leurs coefficients d’absorption sont supérieurs à 4dB sur la bande de fréquence [8-18GHz]. / In this work, the structure and the properties of Polyaniline (PAni) based nanocomposites are investigated with the dual objective of conceiving an ammonia sensor with very low detection limit and a light electromagnetic shielding structure.Aspects relating to the band structure, the doping, the electron transport and percolation phenomena are discussed. Then, the preparation of composites was made from the doping of PAni by Camphor Sulfonic Acid (CSA), which allows the protonation of PAni in its insulating form (Emeraldine base). The molar ratio of the protonation ranges from 5% to 50%. However, when the PAni is doped, the mechanical properties are not compatible with the targeted applications. Therefore, it is essential to make blends with thermoplastics to combine the electrical properties of PAni with the mechanical properties of thermoplastic. In case of ammonia sensor, we particularly studied the influence of the nature of the host matrix and the effect of the doping level on the sensor metrological characteristics. The choice of the matrix and the stoichiometry between PAni and acid directly impact the detection threshold and the amplitude of the sensor response. The results obtained demonstrate the possibility to detect concentrations of ammonia of about 10 ppb using composite based on PAni doped CSA, with a molar ratio of 25%, dispersed in Polyurethane (Pu) matrix. In the second part of this work, we have developed a hybrid multilayer material, based on PAni doped CSA and magnetic nanoparticles. The influence of electrical properties of each layer on the material performance was studied. A bilayer structure has been optimized for industrial standards (shielding effectiveness SE>40 dB) and military standards (SE>80 dB) of electromagnetic shielding. The total thicknesses that were retrieved are 530µm for SE>40 dB and 870µm for SE>80 dB. The realized structures are also able to absorb much of the incident waves, their absorption coefficients are greater than 4 dB over the frequency band [8-18GHz].