Rapidly assembled tent structures are temporary enclosures used to house people or goods. Their uses vary to include recreation, refugee housing, and military shelters. The structural concepts applied in these shelters are as variable as their uses. Some make use of a tensioned fabric and pole system to provide structural strength. Others have a load-bearing frame with attached fabric skin. Further variants make use of inflatable arches or consist of modular containers. Analysis of a number of different types of rapidly assembled tent structures reveals an area where innovation can occur. Conflicts in the last ten years suggest that rapidly assembled shelters for both military purposes and humanitarian relief have the greatest need for innovative solutions. Existing shelters used by the military lack the versatility and speed of deployment necessary in modern conflict. The lack of scalability in the designs makes it difficult to use an existing tent in different situations. They are slow to construct, heavy, and difficult to transport in large numbers. These problems suggest that there is a need for new shelters that better meet the needs of the military. The application of deployable structures technology meets military's needs for structures with the advantages of a small compacted volume, rapid assembly, and ease of deployment. This makes them ideal for application to shelter structures. The aim of this dissertation was to develop a new type of deployable, long-span shelter frame based upon tiled Bennett mechanisms. An overlapping combination of equilateral Bennett mechanisms yields a structure that opens into a half-cylinder shape, providing an enclosed space useful and applicable to the problem of deployable shelters. The specific application considered in the design portion of this process will be a long-span deployable shelter capable of housing military helicopters. This report details the development of the Bennett Shelter concept. Its deployed and compacted geometries are explored, and a procedure for determining structural properties and dimensions is presented. The full concept for the structure, from outer covering to foundation support is then detailed. Loads affecting the structure are determined, and the process of modelling and analysing the structure is then considered. Optimisation of the structure with respect to weight and serviceability requirements is conducted using a number of different materials, and full analysis of the optimal geometries is completed. As no method exists for evaluating the effect of imperfections on the deployment of overconstrained mechanisms, a procedure is derived. The effects of manufacturing imperfections on deployment of the Bennett mechanism are then explored using the method. A full examination of the variation of energy within the Bennett Shelter during deployment provides valuable insight into the performance of the structure. With the above analysis complete, it is shown that the Bennett Shelter is viable as a long-span deployable shelter.

Práticas inadequadas de descontaminação, desinfecção e esterilização de materiais médico-hospitalares têm propiciado o surgimento de inúmeros surtos de infecções por \'Micobactérias de Crescimento Rápido\' (MCR), em todo o Brasil. Entre os anos de 2000 a 2008 foram relatados mais de 2000 casos confirmados de infecções por MCR, sendo que os procedimentos por vídeo se constituíram como os maiores veiculadores destes microrganismos. O aumento do emprego de dispositivos de natureza polimérica em procedimentos médico-cirúrgicos e ausência/não cumprimento de protocolos de processamento destes materiais podem estar envolvidos na disseminação, principalmente, pela capacidade de MCR produzirem e sobreviverem em sistemas de biofilmes. Desta forma, este trabalho teve como objetivo a avaliação da susceptibilidade de cepas de Mycobacterium abscessus subsp. bolettii (suspensão e biofilmes), causadoras ou não de surto, frente a desinfetantes químicos constituídos de: Glutaraldeído 2%, Ácido Peracético 0,2%, Peróxido de Hidrogênio 35%, Solução Alcoólica de Digluconato de Clorexidina 0,5%, Solução Aquosa de Clorexidina 0,2%, Compostos de Amônio Quaternário 1,2%, Iodo 1% e Fenol 5% e Sistemas de Esterilização por Plasma (RIE e ICP) empregando mistura gasosa O2-H2O2. Paralelamente, suportes poliméricos (PVC, PEAD, PP, PUR e PC) empregados como carreadores de MCR foram analisados por Espectroscopia Fotoacústica no Infravermelho (PAS-FTIR), Microscopia Eletrônica de Varredura (MEV), microanálise em Sistema Energy Dispersive Spectroscopy (EDS) e Perfilometria. Resultados destas investigações demonstraram a resistência das cepas de M. abscessus subsp. bolettii, isolada do surto ocorrido em Belém, frente a Glutaraldeído 2%, Solução Alcoólica de Digluconato de Clorexidina 0,5%, Solução Aquosa de Clorexidina 0,2%, Compostos de Amônio Quaternário 1,2% e Iodo 1%. Entretanto, estas cepas foram altamente sensíveis à Ácido Peracético 0,2%, Peróxido de Hidrogênio 35% e Fenol 5% e Sistema de Esterilização por Plasma (RIE). Em sistemas de biofilmes, as cepas padrão e M. abscessus subsp. bolletii se apresentaram resistentes a todos os desinfetantes estudados. Nos estudos envolvendo a integridade de polímeros frente a processos por plasma foram demonstradas modificações em nível superficial (oxidação e aumento da rugosidade) em todos os materiais processados, sendo que o sistema ICP apresentou-se mais agressivo em relação àquele empregando RIE. / Numerous outbreaks of Rapid Growth of Mycobacteria (RGM) have been associated with decontamination, disinfection and sterilization malpractices, in Brazil. Between 2000-2008 were reported more than 2,000 confirmed cases due to RGM infections, and the video procedures were considered to carry these microorganisms. The increased use of medical devices in surgical procedures may be involved in the RGM spreading by its ability to grow and survive in biofilm systems. The aim of this study was evaluate the susceptibility of Mycobacterium abscessus subsp. bolletii (outbreak and nonoutbreak strains) to chemical disinfectants: Glutaraldehyde 2%, Peracetic Acid 0.2%, Hydrogen Peroxide 35%, Chlorhexidine Digluconate 0.5%, Chlorhexidine 0.2%, Iodine 1%, Quaternary Ammonium Compounds 1.2%, and Phenol 5%. Plasma Sterilization Technologies (Reactive Ion Etching and Inductively Coupled Plasma) were also evaluated. Polymers employed in medical devices (Polyvinyl chloride, High-Density Polyethylene, Polycarbonate, Polypropylene, and Polyurethane) were analyzed by Photoacoustic Infrared Spectroscopy (PAS-FTIR), Scanning Electron Microscopy (SEM), System Energy Dispersive Spectroscopy (EDS) and Profilometry. The results have demonstrated the resistance of Mycobacterium abscessus subsp. bolletii isolated from the Belém (PA) outbreak considering chemical exposition to Glutaraldehyde 2%, Chlorhexidine Digluconate 0.5%, Chlorhexidine 0.2%, Quaternary Ammonium Compounds 1.2%, and Iodine 2%. However, these strains were highly sensitive to Peracetic Acid 0.2%, Hydrogen Peroxide 35%, and Phenol 5%. The M. abscessus subsp. bolletii strains have been presented resistant to all disinfectants studied, in biofilm systems. Studies involving polymer integrity demonstrated changes in surface (oxidation and roughness) on all processed materials, and the ICP system was more aggressive in contrast to Reactive Ion Etching.

Tato diplomová práce práce se zabývá plánováním cesty všesměrového mobilního robotu pomocí algoritmu RRT (Rapidly-exploring Random Tree – Rychle rostoucí náhodný strom). Teoretická část popisuje základní algoritmy plánování cesty a prezentuje bližší pohled na RRT a jeho potenciál. Praktická část práce řeší návrh a tvorbu v zásadě multiplatformní C++ aplikace v prostředí Windows 7 za použití aplikačního frameworku Qt 4.8.0, která implementuje pokročilé RRT algoritmy s parametrizovatelným řešičem a speciálním dávkovým režimem. Tento mód slouží k testování efektivnosti nastavení řešiče pro dané úlohy a je založen na post-processingu a vizualizaci výstupu měřených úloh pomocí jazyka Python. Vypočtené cesty mohou být vylepšeny pomocí zkracovacích algoritmů a výsledná trajektorie odeslána do pohonů Maxon Compact Drive všesměrové mobilní platformy pomocí CANopen. Aplikace klade důraz na moderní grafické uživatelské rozhraní se spolehlivým a výkonným 2D grafickým engine.

Small UAVs are used for low altitude surveillance flights where unknown obstacles can be encountered. These UAVs can be given the capability to navigate in uncertain environments if obstacles are identified. This research presents an obstacle avoidance system for small UAVs. First, a mission waypoint path is created that avoids all known obstacles using a genetic algorithm. Then, while the UAV is in flight, obstacles are detected using a forward looking, onboard camera. Image features are found using the Harris Corner Detector and tracked through multiple video frames which provides three dimensional localization of the features. A sparse three dimensional map of features provides a rough estimate of obstacle locations. The features are grouped into potentially hazardous areas. The small UAV then employs a sliding mode control law on the autopilot to avoid obstacles. This research compares rapidly-exploring random trees to genetic algorithms for UAV pre-mission path planning. It also presents two methods for using image feature movement and UAV telemetry to calculate depth and detect obstacles. The first method uses pixel ray intersection and the second calculates depth from image feature movement. Obstacles are avoided with a success rate of 96%.

This thesis focuses on the design and development of a fixed wing micro air vehicle (MAV) and on the development of randomized sampling based motion planning and control algorithms for path planning and stabilization of the MAV. In addition, the thesis also contains probabilis-tic analyses of the algorithmic properties of randomized sampling based algorithms, such as completeness and asymptotic optimality. The thesis begins with a detailed discussion on aerodynamic design, computational fluid dy-namic simulations of propeller wake, wind tunnel tests of a 150mm fixed wing micro air ve-hicle. The vehicle is designed in such a way that in spite of the various adverse effects of low Reynolds number aerodynamics and the complex propeller wake interactions with the airframe, the vehicle shows a balance of external forces and moments at most of the operating conditions. This is supported by various CFD analysis and wind tunnel tests and is shown in this thesis. The thesis also contains a reasonably accurate longitudinal and lateral dynamical model of the MAV, which are verified by numerous flight trials. However, there still exists a considerable amount of model uncertainties in the system descrip-tion of the MAV. A robust feedback stabilized close loop flight control law, is designed to attenuate the effects of modelling uncertainties, discrete vertical and head-on wind gusts, and to maintain flight stability and performance requirements at all allowable operating conditions. The controller is implemented in the MAV autopilot hardware with successful close loop flight trials. The flight controller is designed based on the probabilistic robust control approach. The approach is based on statistical average case analysis and synthesis techniques. It removes the conservatism present in the classical robust feedback design (which is based the worst case de-sign techniques) and associated sluggish system response characteristics. Instead of minimizing the effect of the worst case disturbance, a randomized techniques synthesizes a controller for which some performance index is minimized in an empirical average sense. In this thesis it is shown that the degree of conservatism in the design and the number of samples used to by the randomized sampling based techniques has a direct relationship. In particular, it is shown that, as the lower bound on the number of samples reduces, the degree of conservatism increases in the design. Classical motion planning and obstacle avoidance methodologies are computationally expen-sive with the number of degrees of freedom of the vehicle, and therefore, these methodologies are largely inapplicable for MAVs with 6 degrees of freedom. The problem of computational complexity can be avoided using randomized sampling based motion planning algorithms such as probabilistic roadmap method or PRM. However, as a pay-off these algorithms lack algorith-mic completeness properties. In this thesis, it is established that the algorithmic completeness properties are dependent on the choice of the sampling sequences. The thesis contains analy-sis of algorithmic features such as probabilistic completeness and asymptotic optimality of the PRM algorithm and its many variants, under the incremental and independent problem model framework. It is shown in this thesis that the structure of the random sample sequence affects the solution of the sampling based algorithms. The problem of capturing the connectivity of the configuration space in the presence of ob-stacles, which is a central problem in randomized motion planning, is also discussed in this thesis. In particular, the success probability of one such randomized algorithm, named Obsta-cle based Probabilistic Roadmap Method or OBPRM is estimated using geometric probability theory. A direct relationship between the weak upper bound of the success probability and the obstacle geometric features is established. The thesis also contains a new sampling based algorithm which is based on geometric random walk theory, which addresses the problem of capturing the connectivity of the configuration space. The algorithm shows better performance when compared with other similar algorithm such as the Randomized Bridge Builder method for identical benchmark problems. Numerical simulation shows that the algorithm shows en-hanced performance as the dimension of the motion planning problem increases. As one of the central objectives, the thesis proposes a pre-processing technique of the state space of the system to enhance the performance of sampling based kino-dynamic motion plan-ner such as rapidly exploring random tree or RRT. This pre-processing technique can not only be applied for the motion planning of the MAV, but can also be applied for a wide class of vehicle and complex systems with large number of degrees of freedom. The pre-processing techniques identifies the sequence of regions, to be searched for a solution, in order to do mo-tion planning and obstacle avoidance for an MAV, by an RRT planner. Numerical simulation shows significant improvement over the basic RRT planner with a small additional computa-tional overhead. The probabilistic analysis of RRT algorithm and an approximate asymptotic optimality analysis of the solution returned by the algorithm, is also presented in this thesis. In particular, it is shown that the RRT algorithm is not asymptotically optimal. An integral part of the motion planning algorithm is the capability of fast collision detection between various geometric objects. Image space based methods, which uses Graphics Pro-cessing Unit or GPU hardware, and do not use object geometry explicitly, are found to be fast and accurate for this purpose. In this thesis, a new collision detection method between two convex/non-convex objects using GPU, is provided. The performance of the algorithm, which is an extension of an existing algorithm, is verified with numerous collision detection scenarios.

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This project investigated the implementation and evaluation of various collision-free path planning algorithms for the Saab Seaeye eM1-7 6-DOF Electric Manipulator (eManip). The primary goal was to enhance the autonomous performance of the eManip by integrating efficient path planning methodologies, ultimately ensuring the avoidance of collisions and manipulator singularities during underwater operations. Key algorithms examined included the Rapidly-exploring Random Trees (RRT) algorithm and its enhanced variants. Through simulation tests in MATLAB and Gazebo, metrics such as planning time, path length, and the number of explored nodes were evaluated. The results highlighted the robustness of Goal-biased and Bidirectional RRT* (Gb-Bd-RRT*), which consistently performed well across various environments. The research also highlighted the correlation between algorithm effectiveness and specific task attributes, emphasizing their adaptability to complex environments. This research contributes valuable insights into the effectiveness of path planning algorithms, informing the selection and integration of viable strategies for 6-DOF robotic manipulators.