Exoskeletons are rapidly emerging from the realm of science-fiction myth to practical reality in everyday life. Various designs have provided viable means for individuals to regain capabilities that were lost or perform tasks not previously possible by their ability alone. In this research, I propose two novel exoskeletons for walking assistance and heavy load carriage. The first exoskeleton can be used to provide assistance for walking in various applications such as industrial productivity, rehabilitation, and military or space training. We introduce a design for a lower body wearable device that supports up to 80% of the user's body weight (667 N peak force) with a single actuator on each leg. Its underactuated design directs force through the user's center of mass with a single sprocket-chain driven prismatic actuator on each leg, allowing for natural gait and mobility. The device is optimized for simplicity, ease of assembly, low cost, and weight. The second design aims to counteract the one of the leading causes of injury in the workplace, repetitive and heavy lifting. The Heavy Lift and Carry Exoskeleton (HeavyLC Exo) is capable of safely lifting and carrying loads up to 36 kg (80 lbs) while minimizing the number of actuators to reduce weight and complexity. The HeavyLC Exo allows the user to direct the object, pause and hold the object steady mid-lift, and follow the natural kinematics of lifting. It is secured to the user with shoulder, chest, and dual thigh straps, along with an adjustable waist belt and overshoe attachment. Powered by two 14.8 V batteries and an off-board air compressor, the HeavyLC Exo has a total of 20 DOF, with 6 actuated DOF and 14 free DOF. The arms use only two actuators each, providing powered lifting and arm retraction/extension, and allowing a wide range of body postures; the legs are powered by single pneumatic actuators on each leg connected to the foot accompanied by a passive spring element to prevent excessive pelvic tilt and leg abduction during swing. The control system requires directional forces from the user at the tool handle of 19 N (4.3 lbf) on average. Current design limitations necessitate the user to provide up to 280 N (62.9 lbf) at the hip during worst load conditions, and future design optimization is proposed. A fully functional prototype of HeavyLC Exo is built, fully tested, and analyzed for improvement. / Master of Science / Exoskeletons, which were once only seen in science fiction, are now becoming a reality in everyday life. Various designs have made it possible for people to do things they couldn't do before or regain abilities they lost. In this research, two new exoskeletons are proposed - one for walking assistance and the other for carrying heavy loads. The first exoskeleton is designed to help people walk. It supports up to 80 % of the user's body weight with a single actuator on each leg, which directs force through the center of mass, allowing for natural gait and mobility. It's simple, easy to assemble, low-cost, and lightweight, making it useful in various applications such as medical rehabilitation, military or space training, and industrial productivity. The second exoskeleton is designed to help people lift and carry heavy objects, which is a common cause of workplace injuries. The Heavy Lift and Carry Exoskeleton (HeavyLC Exo) can safely lift and carry objects up to 36 kg (80 lbs) while minimizing the number of actuators to reduce weight and complexity. It's worn by the user using shoulder, chest, and dual thigh straps, along with an adjustable waist belt and overshoe attachment. The exoskeleton is powered by two batteries and an off-board air compressor, and has 20 degrees of freedom, with 6 powered and 14 non-powered, giving it significant flexibility to conform to lifting and walking motions allowing it to function with normal user range of motion. The arms use two actuators each to provide powered lifting and arm retraction/extension, while the legs are powered by single pneumatic actuators on each leg connected to the foot accompanied by a elastic spring element. The control system requires the user to lift and maneuver about 1.9 kg (4.2 lbs) to direct the object. A fully functional prototype has been built, tested, and analyzed for changes in the future.

In order to remain competitive in the global market businesses are under ever increasing pressure to ramp up production rates whilst simultaneously improving cost effectiveness to allow continued profitable growth. This requirement is particularly challenging in high value manufacturing which is characterised by expensive product and manufacturing systems and relatively low production volume. This thesis introduces a method for the design of robust and reliable manufacturing processes through the prevention of identified potential failure modes that is based on the principles of the existing Failure Mode Avoidance framework used for automotive system design. The tools and techniques that exist in the literature are reviewed in order to understand the best practice, and subsequently a Manufacturing Failure Mode Avoidance framework is designed. This framework is demonstrated through two unique case studies conducted in a real life manufacturing environment in order to validate its appropriateness to provide robust countermeasures to failure which will allow right first time manufacture. The outcomes of the implementations are discussed, conclusions drawn and opportunities for further research are provided.

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The problem is to determine the status of the methods of inventory valuation in Texas Cotton Mills. This study is also conducted to determine how much uniformity, if any, exists in this particular industry.

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The drying of sugar is the last step in the recovery of solid sugar from sugar-cane. To ensure that the sugar can be transported and stored, the final moisture content leaving the sugar mill must be carefully controlled. Data spanning periods of normal plant operation were collected at the Tongaat-Hulett Ltd Darnall sugar mill. These measurements were reconciled to achieve instantaneous mass and energy balances across the sugar dryer. Using these measurements, a general model has been developed to simulate the sugar drying. It includes ten compartments through which the sugar and drying air flow, with a mass and energy balance in each compartment. It was assumed that a "film" around the sugar crystal is supersaturated, and that crystallisation is still occurring. A sorption isotherm determining the equilibrium moisture content of the sugar, at which point mass transfer ceases, was included. The model has been matched to process measurements by adjusting the heat and mass transfer coefficients. A Dynamic Matrix Controller was developed and tested off-line on the model, using the reconciled measurement sequences. The controller manipulated the inlet air temperature in order to control the exit sugar moisture content. The model predictive control format successfully dealt with the large process dead-time (5 minutes). / Thesis (M.Sc.Eng.)-University of Natal, Durban, 2001.

Entre 1848 et 1914, un groupe de peintres exerça une « mainmise » sur la Manufacture de Beauvais. Pierre-Adolphe Badin et son fils, Jules, Pierre-Adrien Chabal-Dussurgey et Jules Diéterle en furent tour à tour les administrateurs et les principaux cartonniers. Chacun était issu d’une formation différente, de la plus courue à la moins reconnue : des Beaux-arts de Paris à l’école de l’industrie. Malgré la diversité de leur parcours, la Révolution de 1848 les rassembla au sein des Manufactures nationales, où ils participèrent à la régénération des arts décoratifs français. Il s’agit de comprendre les choix esthétiques de la Manufacture à travers deux niveaux d’analyse : celui des individus et de leur réseau, en les resituant ensuite dans le contexte plus général de l’industrie textile de la seconde moitié du XIXe siècle. / Between 1848 and 1914, a group of painters had a “stranglehold” on the Beauvais tapestry Manufacture. Pierre-Adolphe Badin and his son, Jules, Pierre-Adrien Chabal-Dussurgey and Jules Diéterle were in turns the managers and the main cartoon painters of this manufacture. They all came from different backgrounds: two of them attended the Fine Arts School of Paris, while the others ones were trained in the industry. Despite the diversity of their artistic careers, the French Revolution of 1848 brought these painters together within the National Manufactories, where they contributed to the revival of the French decorative arts. The aesthetic choices of the Beauvais Manufacture will be analyzed through the lens of these individual people and their network, while taking into account the global context of the textile industry during the second half of the nineteenth century.

Thesis (Ph. D.)--Columbia University. / Title from electronic title page (viewed Aug. 26, 2002). This electronic edition is part of the UNC-CH digitization project's database, Documenting the American South. It is a part of the collection The North Carolina experience, beginnings to 1940. Text scanned (OCR) by Apex Data Services, Inc. Images scanned by Tammy Evans. Text encoded by Apex Data Services, Inc., Melissa Meeks and Natalia Smith. Includes bibliographical references.

<p>  </p> <p>The additive manufacturing of energetic materials is a novel way to alter the properties of an energetic material without necessarily changing its chemical structure. There are many methods of additive manufacturing which can be applied to energetic material fabrication, each of which have unique advantages and disadvantages. The most well characterized additive manufacturing method is the commercially refined technique of fused filament fabrication (FFF) printing. FFF manufacturing techniques can be applied to additively manufacture thermoplastic energetic materials. The thermoplastic aluminum and polyvinylidene difluoride (Al/PVDF) system is suitable for manufacture with FFF techniques, shapeable into pyrotechnics with custom geometries using commonly available FFF printers. This theoretically allows Al/PVDF systems to be tailored for a wide variety of multifunctional needs, such as reactive structures. Following a literature review describing energetic material additive manufacturing techniques, this thesis focuses on the creation of outwardly identical Al/PVDF samples and the use of a geometric correction factor to control for uneven feedstock diameter. By varying the infill pattern, infill density, and interior geometry, different sample energy densities were obtained and observed during combustion. High speed videography measurements and the mass of individual samples were used to estimate the overall energy release rate. An Ashby plot contrasting the energy density and energy release rate was obtained. While full density printed samples burned similar to cast propellant strands in a linear burn, the energy release rates of additively manufactured Al/PVDF could be increased via convective combustion by varying the infill type and density. These results have significance for the fields of structural energetic materials and for additive manufacturing studies of energetic materials.</p>