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Requirements, specifications and deployment models for autonomous jobsite safety proximity monitoringLuo, Xiaowei 24 July 2013 (has links)
Construction has a higher injury and fatality rate than most of the other industries. Given this situation, existing research has studied various issues and factors affecting construction safety management and has attempted to use all available methods to improve the construction safety performance. However, the construction accident rate remains among the highest in the United States and the world. The primary objective of this research is to advance autonomous proximity monitoring and hence provide a safer environment for construction workers. In particular, I seek to advance current evaluations of proximity warning technologies to a more robust engineering approach to the design and deployment of autonomous safety monitoring systems. The contributions of the research are demonstrated through specifications, deployments, and testing of proximity monitoring systems for crane loads and falling from height. My research advances current knowledge in three areas. First, I develop specifications for proximity safety monitoring in a sensed environment, built from existing guidelines and expert interviews. Second, I translate the specifications to computer interpretable rules and deploy them in a distributed computing environment. This demonstrates the feasibility of a systems approach and reusability of components to speed deployment. Third, I evaluate the accuracy of the specifications and systems under imperfect data. I further evaluate some approaches to dealing with imperfect data. Collectively, these advances move existing proximity warning research from evaluation of specific systems to an engineering approach to development and deployment of distributed systems with reusable components that explicitly treats imperfect data. / text
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Control of human-operated machinery with flexible dynamicsMaleki, Ehsan A. 13 January 2014 (has links)
Heavy-lifting machines such as cranes are widely used at ports, construction sites, and manufacturing plants in a variety of material-transporting applications. However, cranes possess inherent flexible dynamics that make fast and precise operation challenging. Most cranes are driven by human operators, which adds another element of complexity. The goal of this thesis is to develop controllers that allow human operators to easily and efficiently control machines with flexible dynamics. To improve the ease of human operation of these machines, various control structures are developed and their effectiveness in aiding the operator are evaluated. Cranes are commonly used to swing wrecking balls that demolish unwanted structures. To aid the operator in such tasks, swing-amplifying controllers are designed and their performance are evaluated through simulations and experiments with real operators. To make maneuvering of these machines in material-transporting operations easier, input-shaping control is used to reduce oscillation induced by operator commands. In the presence of external disturbances, input shaping is combined with a low-authority feedback controller to eliminate unwanted oscillations, while maintaining the human operator as the primary controller of the machine. The performance and robustness of the proposed controllers are thoroughly examined via numerical simulations and a series of experiments and operator studies on a small-scale mobile boom crane and a two-ton dual-hoist bridge crane.
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"Worth living and worth giving" : Charles R. Crane et le progressisme wilsonien : la philanthropie comme moyen de réformeLeclair, Zacharie 04 1900 (has links) (PDF)
Au cœur du mouvement progressiste aux États-Unis et alors que le réformisme consolide sa place en politique nationale grâce à l'élection de Woodrow Wilson en 1912, émerge à côté du nouveau président élu la figure de Charles Richard Crane (1858-1939), auparavant quasi-inconnu sur la scène nationale. Industriel richissime, réformateur, mécène et philanthrope de Chicago, Crane avait fait sa marque dans les cercles progressistes du Midwest en plus d'avoir soigneusement cultivé des relations importantes à l'étranger. En même temps, ses intérêts et ses accointances variés le rendirent utiles aux yeux de Wilson qui l'intégra dans un cercle très sélect de conseillers intimes. Rapidement devenu ami avec le président, Crane fut tour à tour choisi pour de multiples tâches politico-diplomatiques de relative importance : contributeur majeur des élections de Wilson en 1912 et 1916, promoteur et facilitateur des réformes sociales et politiques du programme de la New Freedom, mission diplomatique en Russie révolutionnaire, soutien à la création de la Tchécoslovaquie, commission d'experts au Moyen-Orient dans le cadre de la Paix de Versailles et ambassade américaine en Chine comptent parmi ses principales tâches au sein du wilsonisme. À travers ces années avec Wilson, les plus déterminantes de sa vie à ses propres yeux, s'écrivit une carrière publique remarquable qui illustre des aspects du wilsonisme à la fois caractéristiques et inédits. Son engagement dans un réformisme assez radical, qui se manifesta autant dans la sphère nationale, avec des politiques agraires et anti-monopolistiques, qu'à l'étranger, avec l'appui à des causes révolutionnaires, anti-impérialistes et humanitaires, et la constance de son discours wilsonien et de son appui à Wilson apportent un éclairage différent à la perspective historienne du progressisme wilsonien et de l'époque qui l'a produit et façonné.
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MOTS-CLÉS DE L’AUTEUR : Charles Richard Crane, Woodrow Wilson, relations internationales, Première Guerre mondiale, histoire de États-Unis, ère progressiste
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Robust Control For Gantry CranesCosta, Giuseppe, Electrical Engineering & Telecommunications, Faculty of Engineering, UNSW January 1999 (has links)
In this thesis a class of robust non-linear controllers for a gantry crane system are discussed. The gantry crane has three degrees of freedom, all of which are interrelated. These are the horizontal traverse of the cart, the vertical motion of the goods (i.e. rope length) and the swing angle made by the goods during the movement of the cart. The objective is to control all three degrees of freedom. This means achieving setpoint control for the cart and the rope length and cancellation of the swing oscillations. A mathematical model of the gantry crane system is developed using Lagrangian dynamics. In this thesis it is shown that a model of the gantry crane system can be represented as two sub models which are coupled by a term which includes the rope length as a parameter. The first system will consist of the cart and swing dynamics and the other system is the hoist dynamics. The mathematical model of these two systems will be derived independent of the other system. The model that is comprised of the two sub models is verified as an accurate model of a gantry crane system and it will be used to simulate the performance of the controllers using Matlab. For completeness a fully coupled mathematical model of the gantry crane system is also developed. A detailed design of a gain scheduled sliding mode controller is presented. This will guarantee the controller's robustness in the presence of uncertainties and bounded matched disturbances. This controller is developed to achieve cart setpoint and swing control while achieving rope length setpoint control. A non gain scheduled sliding mode controller is also developed to determine if the more complex gain scheduled sliding mode controller gives any significant improvement in performance. In the implementation of both sliding mode controllers, all system states must be available. In the real-time gantry crane system used in this thesis, the cart velocity and the swing angle velocity are not directly available from the system. They will be estimated using an alpha-beta state estimator. To overcome this limitation and provide a more practical solution an optimal output feedback model following controller is designed. It is demonstrated that by expressing the system and the model for which the system is to follow in a non-minimal state space representation, LQR techniques can be used to design the controller. This produces a dynamic controller that has a proper transfer function, and negates the need for the availability of all system states. This thesis presents an alternative method of solving the LQR problem by using a generic eigenvalue solution to solve the Riccati equation and thus determine the optimal feedback gains. In this thesis it is shown that by using a combination of sliding mode and H??? control techniques, a non-linear controller is achieved which is robust in the presence of a wide variety of uncertainties and disturbances. A supervisory controller is also described in this thesis. The supervisory control is made up of a feedforward and a feedback component. It is shown that the feedforward component is the crane operator's action, and the feedback component is a sliding mode controller which compensates as the system's output deviates from the desired trajectory because of the operator's inappropriate actions or external disturbances such as wind gusts and noise. All controllers are simulated using Matlab and implemented in real-time on a scale model of the gantry crane system using the program RTShell. The real-time results are compared against simulated results to determine the controller's performance in a real-time environment.
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Carregamento crítico de instabilidade geral de pilares de seção composta variável, de edifícios industriais metálicos / not availableJoão Alberto Venegas Requena 18 October 1995 (has links)
Neste trabalho, é apresentado um processo de análise de estruturas de edifícios industriais metálicos, constituídas de pilares de seção composta, com variação brusca de seção ao nível de assentamento da viga de rolamento, e traves em treliça. O processo tem como objetivo a determinação do carregamento crítico que produz a instabilidade elástica geral por flexão ou por flexo-torção, dos pilares supostos engastados na base e vinculados elasticamente na sua extremidade superior à trave do telhado. A estrutura é analisada pelo processo dos deslocamentos, empregando-se a técnica matricial com discretização de seção dos pilares, de modo que todo o pilar discretizado seja representado por uma estrutura tridimensional equivalente composta por barras. Esta análise é desenvolvida no regime elástico, em teoria de segunda ordem, computando as modificações nas condições de equilíbrio decorrentes do estado deslocado da estrutura. Como parte do desenvolvimento do trabalho, é analisado inicialmente os efeitos dos vínculos elásticos na parte superior dos pilares, os quais modificam os comprimentos efetivos de flambagem, considerando o pórtico transversal apenas com elementos de barra deformáveis por flexão em seu plano. Finalmente, é analisado o comportamento completo dos pilares integrados à estrutura do pórtico transversal, considerando-os discretizados e vinculados à trave do telhado. Obtém-se então o limite de estabilidade dos pilares tridimensionais, deformáveis por flexão ou por flexo-torção. Fluxogramas das programações são apresentados para facilitar o entendimento do processo. Exemplos numéricos são apresentados e seus resultados são comparados com os obtidos por outros autores e com os da aplicação de recomendações de normas técnicas. Os resultados mostram que a aplicação do processo proposto fornece parâmetros capazes de representar o comportamento real dos pilares, possibilitando dimensionamentos mais precisos. / This thesis presents a process for analysis of steel industrial buildings, with stepped columns with sudden variation of section at the level of the crane runway girder and truss chords. The process aims at the determination of the global elastic, flexural or flexural-torsional, instability limit for columns with fully restrained rotations at the basis and elastically connected to the chord. The stiffness method is applied, using the matrix analysis technique with discretization of the column elements, resulting an equivalent three-dimensional structure. The analysis is developed in second order theory, in the elastic range, computing the changes in equilibrium due to the deformed shape of the structure. First, the effects of elastic connections at the tops ot the columns are analyzed. These effects are responsible for changes in the effective buckling lengths, considering the transversal frame as beam elements deforming by bending in their own planes. Finally, an analysis is performed for the overall behavior of the whole transversal frame structure, with the discretized columns connected to the frame chord. The stability limit is obtained for the three-dimensional columns, which is deformable by bending or torsion-bending. Flowcharts are presented to help in the process understanding. Numerical examples are presented, comparing to results obtained by other researchers or to specifications from technical norms. Results show that the application ot the proposed approach leads to parameters capable of representing the actual behavior of the columns, thus resulting in more efficient design.
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Sloupový jeřáb mobilní s nosností 600kg / Pillar jib crane with a load capacity 600 kgWojnar, Tomasz January 2017 (has links)
The diploma thesis deals with the design of a mobile crane for working in a manufacturing environment. The crane has load capacity 600 kg, length of radius 3 m and load-lifting height 3m. It is equipped with the electric chain hoist with electric trolley, rotation by held by hand of burden. The diploma thesis contains crane design and control and design calculations of important components. Technical drawings are also part of the thesis.
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Pomocná jeřábová kočka 10000 kg / Auxiliary crane trolley 10000 kgMilichovský, Karel January 2019 (has links)
This master thesis deals with design of auxiliary crab trolley with load capacity 10t. Crab trolley moves along outdoor track of scrab yard. The target of this thesis is calculation and own design of travelling and lifting gear, strength calculation of frame and drawing documentation of a crane trolley assembly.
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Jeřáb nástěnný mobilní / Mobile wall craneBábek, Tomáš January 2019 (has links)
This master’s thesis describes the design of wall mobile crane and its railway. At the beginning of the work research of suitable hoists is conducted according to important parameters. Following the calculation of basic loads applied during crane operation. Furthermore the determination of the static load and fatigue strength of selected part which is verified by MKP simulation. The work continues with design of selected parts of crane and its railway. This design is solved with respect to relevant standards. In conclusion the final design of machine is drawn.
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Vícelodní průmyslová hala / Multibay industrial hallHrabovská, Kristýna January 2020 (has links)
The principal aim of this thesis is to design two possible options for the steel structure of a new multibay industrial hall located in Slavkov u Brna. An overhead crane with load capacity of 12.5 metric tons will by situated in one of the bays. The hall has a rectangular shape with dimensions of 63x48 meters, each of the two bays has dimensions of 63x24 meters, a height of 11.5 meters and a saddle roof with an angle of slope 10°. Both of the options have the same layout design, the only difference is that option 1 has columns with truss girders while option 2 has a transversal frame with a haunch. The first option was selected because it is more economical due to material savings and is design developed in a greater detail. The permanent load on the building is considered and includes the weight of the steel structure, panels and the weight of crane runway. The variable load is also considered due to the live load, snow load, wind load, the crane, and their combination. Steel S235 is used as the construction material.
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Zakázkový projekt na zdvihací zařízení / Custom design for lifting equipmentMatějíčková, Eva January 2020 (has links)
The aim of this thesis is to design and manufacture a lifting device to the Volkswagen Crafter long vehicle. In the first part, I present a simple descriptive overview of different lifting devices based on their principle and use. Next, commercially available alternative solutions to the given problem are shown and discussed. The main goals of the practical part are the design of the lifting device that fits to a carriage van according to given specifications and the description of the technological processes for the manufacturing of individual components of the device. The design includes selection of proper machines, measuring devices and working tools, which was carried out based on the available equipment. Finally, manufacturing, testing and evaluation are described and discussed together with the possibilities for future improvement.
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