Thesis (Ph. D.)--University of Queensland, 2003. / Includes bibliographical references.

The Department of Energy national laboratories, like Los Alamos National Lab or Sandia National Lab, perform work on radioactive and chemically dangerous materials. Gloveboxes are often used to shield workers from these hazards, but they cannot completely eliminate the danger and often create new safety concerns due to reduced operator dexterity and ergonomic posture. When feasible, robots can be employed to remove the human from the radioactive hazard; allowing them to analyze the situation and make decisions remotely. Force sensor data from the manipulator can be used to simplify the control of these remote systems as well as make them more robust. Much research has been done to develop force and torque control algorithms to introduce compliance or detect collisions. Many of these algorithms are very complicated and currently only implemented in research institutions on torque-controlled manipulators. The literature review discusses many such controllers which have been developed and/or demonstrated. This thesis reviews, develops, and demonstrates several beneficial algorithms which can be implemented on commercially-available kinematically-controlled robots using commercially-available sensors with a reasonable investment of time. Force data is used to improve safety and manage contact forces while kinematically controlling the robot, as well as improve the world model. Safety is improved by detecting anomalous and/or excessive forces during operation. Environmental modeling data is inferred from position and/or force data. A six-axis sensor and joint torque sensors on 2 7DOF manipulators are used to demonstrate the proposed algorithms in two DOE relevant applications: remotely opening an incompletely modeled cabinet door and moving a robot in a confined space. / text

Orientador: Mauro Augusto Demarzo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil / Made available in DSpace on 2018-08-06T05:05:30Z (GMT). No. of bitstreams: 1 Paixao_AntonioMedeirosda_M.pdf: 9672207 bytes, checksum: e011879d8aa4447d3e547b2abf30df2a (MD5) Previous issue date: 2005 / Resumo: Este trabalho tem como objetivo o de mostrar experimentalmente a influência que os paletes de madeira podem exercer no comportamento das estruturas de armazenagem do tipo drive in com um nível de carregamento. Considerar o palete com apoios móveis em ambos os braços da estrutura, ou por outro lado, desconsiderá-lo totalmente na análise estrutural, pode resultar em análises irreais, pois o atrito entre o palete e os trilhos pode influenciar no comportamento deste tipo de estrutura. A fim de se verificar a existência desta influência em condições próximas à realidade, dois pórticos com características semelhantes às dos fornecidos pelas empresas fabricantes foram testados com a utilização de três tipos de paletes com características semelhantes às dos paletes encontrados no mercado, com inércias variadas, apoiados sobre trilhos pintados. Estes paletes foram testados sobre trilhos com mesas abrasivas a fim de se verificarem possíveis diferenças nos deslocamentos entre as estruturas carregadas com paletes sobre trilhos pintados e entre as estruturas carregadas com paletes sobre trilhos com mesas abrasivas. Além disso, os pórticos foram testados com um palete suspenso com o objetivo de simular o modelo teórico elaborado pelo Slope-deflection. Cada pórtico foi testado com as forças verticais de 245N, 490N, 735N e 980N aplicadas nos braços e com a força horizontal de 1,5% correspondente ao valor da força vertical aplicada neste pórtico para simular possíveis forças horizontais aplicadas pelas empilhadeiras na movimentação dos materiais. Dois relógios comparadores com sensibilidade de 1/1000mm e um com sensibilidade de um 1/100mm, todos com curso de 10mm, foram colocados, respectivamente, no topo e na base de cada uma das colunas de cada pórtico com o objetivo de se medirem os deslocamentos lineares e angulares destes pórticos. Os deslocamentos medidos nas extremidades de cada coluna foram úteis para se determinar os momentos fletores e as reações nas extremidades destas colunas. A influência dos paletes de madeira no comportamento das estruturas do tipo drivein foi verificada com nível de 5% de significância através da análise da variância / Abstract: This dissertation¿s intent is to investigate experimentally the influence the wood pallets exert on the behavior of the drive in storage racks with one level of loading. To consider the pallets as roller supported on both rails of the structure implies in not to consider the influence of the friction between the pallets and the rails in the behavior of the structure, and thus the results obtained by the theoretical model of analysis may lead to results that may differ from the observed in the real structure. With the aim of investigating this influence in conditions as close as possible to the reality, two frames resembling those supplied by manufacturers were tested with three sort of pallets, each one with characteristics and dimensions resembling the pallets utilized by users, but with different resistance and inertia in comparison with each other. The same pallets were tested in the same frames, but this time on rails with an abrasive surface to verify the possible differences in displacements between the structures loaded with pallets on smooth surfaces rails and between structures loaded with pallets on abrasive surfaces rails. Furthermore, the frames were subjected to a suspense load with the aim of simulating the theoretical model of analysis. Each arm were tested with vertical forces of 245N, 490N, 735N and 980N. It was considered also the horizontal force of 1,5% of the vertical force acting on the frame to take into consideration the lift truck operation. With the aim of measuring the linear and angular displacements of these frames, two dial gages were positioned at the top and one was positioned at the bottom of each column. The readings of all linear and angular displacements at the end of the columns were useful for evaluating the bending moments, the horizontal and vertical reactions acting in each one of the end of the columns of these frames. The 8 elements considered (3 pallets on smooth surface rails, 3 pallets on abrasive surface rails, 1 suspense load and 1 for the Slope-Deflection Method) were combined in groups of 3, so that the influence of the wood pallets in the behavior of drive in racks can be investigated through the variance analysis with 5% in the level of significance / Mestrado / Estruturas / Mestre em Engenharia Civil

Purpose: The purpose of this study is to examine the problems that occur due to moist in the workplace, as well as the measures that can be taken and which measures are most effective. The study will examine the material storage and how it is being handled in the workplace, exploring what directives the insurance companies have, so the insurance is valid. Lastly the study will compare the different measures based on an economic perspective, time perspective as well as material savings. Method: This study is based on a literature study and a case study. The case study is based on both an interview and a site visit. Information has been gathered from various sources such as books, previously made thesis and various governments websites. The case study for this thesis is conducted at Emausskolan in Västerås. Results: To ensure that the moisture management in the production is good a certified moisture expert is hired. Moisture on materials can be prevented by using just-in-time deliveries and the most optimal solution a weather protection. Directives from the insurance companies regarding moisture management at the workplace and what the entrepreneur is obligated to do after moisture damage has occurred. To minimize moisture and mold growth the workplace should be clean and dry. Self-monitoring and samples were carried out throughout the project to ensure that the work has been performed correctly. Conclusions: The conclusion for this thesis is that challenges for moisture depends on the weather, carelessness, and time pressed schedules. Solutions would be to have a tight climate shell, usage of weather protection and surface treatment on materials. Handling of materials is to a certain degree taken care of in terms of palletized and packaged but not always.

Höga byggkostnader och betydande bostadsbrist i Sverige visar att ett effektivare bostadsbyggande krävs. En reducering av slöseri i byggprocessen bidrar till en effektivisering av både tid och kostnad. För att öka förståelsen för vikten av effektivisering synliggör den här studien slöseri i produktionsflödet för en platsgjuten betongvägg i ett bostadsprojekt. Studien visar även var i produktionsflödet det finns förbättringsmöjligheter. Slöseriet synliggjordes genom en tidsstudie som visade på stor potential till förbättring i bostadsprojektets resursflöde, materialflöde och informationsflöde. Mycket tyder på att dessa brister i produktionsflödet beror på allt för kort byggtid, vilket leder till att en fullgod planering inte alltid utförs. / High construction costs and considerable housing shortages in Sweden show that a more efficient housing construction is required. A reduction of waste in the construction process contributes to the efficiency of both time and cost. In order to increase the understanding of the importance of efficiency, this study reveals waste in the production flow of a cast in-situ concrete wall in a housing project. The study also shows where in the production flow there are improvement opportunities. The waste was made visible through a time study which showed great potential for improvement in the housing project resource flow, material flow and information flow. There are many indications that these shortcomings in the production flow are due to a too short construction time, which means that a good planning is not always carried out.