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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Two Axis Fixture Calibration Utilizing Industrial Robot Artifact Object Touch Sensing

Benton, Thomas Henry 22 June 2020 (has links)
No description available.
42

Wind Tunnel Testing of a Variable Camber Compliant Wing with a Unique Dual Load Cell Test Fixture

Zientarski, Lauren Ann January 2015 (has links)
No description available.
43

Mechanické vlastnosti nízkouhlíkových a nízkolegovaných ocelí, stanovené pomocí protlačovacích zkoušek na miniaturních discích při pokojové a snížených teplotách / Determination of mechanical properties of low carbon and low alloy steels via small punch tests at room and low temperatures

Závodský, Peter January 2016 (has links)
The presented diploma thesis deals with an innovative material test, so called Small Punch Test. There are main principles, advantages and limitations of the test stated in the thesis. There are stated also correlation procedures in order to obtain standard mechanical properties. A test fixture design has been done in order to perform test procedures at temperature range from 80 to 25 °C. Twelve experimental curves have been obtained from the test and typical quantities have been evaluated. The different accuracy of correlations with standard mechanical properties has been obtained using different correlation equations.
44

CAFixD: A Case-based Reasoning Method for Fixture Design

Boyle, Iain Mackinnon 04 May 2006 (has links)
Fixtures accurately locate and secure a part during machining operations such that the part can be manufactured to design specifications. To reduce the design costs associated with fixturing, various computer-aided fixture design (CAFD) methods have been developed through the years to assist the fixture designer. Much research has been directed towards developing systems that determine an optimal fixture plan layout, but there is still a need to develop a CAFD method that can continue to assist designers at the unit level where the key task is identifying the appropriate structure that the individual units comprising a fixture should take. This research work details the development of a CAFD methodology (called CAFixD) that seeks to fill this hole in the CAFD field. The approach taken is to consider all operational requirements of a fixture problem, and use them to guide the design of a fixture at the unit level. Based upon a case-based reasoning (CBR) methodology where relevant design experience is retrieved and adapted to provide a new fixture design solution, the CAFixD methodology adopts a rigorous approach to indexing design cases in which axiomatic design functional requirement decomposition is adopted. Thus, the design requirement is decomposed in terms of functional requirements, physical solutions are retrieved and adapted for each individual requirement, and the design re-constituted to form a complete fixture design. Case adaptation knowledge is used to guide the retrieval process. Possible adaptation strategies for modifying candidate cases are identified and then evaluated. Case and adaptation strategy combinations that result in adapted designs that best satisfy the preferences of the designer are used as the final design solutions. Possible means of refining the effectiveness of the method include combining adaptation strategies and considering the order in which design decisions are taken.
45

Flygplanstillverkning : Fixturkoncept till robotgradning / Concept generation of deburring fixture for robot operation

Hansson, Anders, Kylander, Robert January 2009 (has links)
<p>Volvo Aeros flygmotortillverkning i Trollhättan har infört ett antal nya detaljvarianter i produktionen. Detta har medfört att den robotcell som är avsedd att utföra en avgradningsoperation är i behov av uppdatering av både hårdvara och mjukvara. Denna rapport följer framtagningen av fixturkoncept som möjliggör att robotcellen kan användas även till de nya detaljerna. De förslag som arbetats fram sträcker sig från enklast möjliga till mer avancerade och nytänkande funktioner. Samtliga funktioner och koncept har genomgått gallringar i ett flertal steg. Förslagen har slutligen kombinerats och poängbedömts med konceptgenereringsverktyg till grund.</p><p>Efter en objektiv poängbedömning av sex olika koncept baserad på concept scoring visar sig två huvudgrupper med tre koncept i varje. Den ena gruppen bygger på en mer avancerad konstruktion med behov av två rotationsaxlar. Dessa medför ett flertal fördelar gällande effektivitet, men även påtagliga nackdelar vad gäller ekonomiska aspekter och idrifttagandetid. Den andra gruppen av koncept baseras mer på det befintliga fixturkonceptet. Detta medför fördelar gällande idrifttagandetid och kostnader.</p><p>Ett huvudkoncept som efter poängbedömningen visat sig mest lämpligt presenteras mer ingående och slutligen förs en diskussion gällande resultatets utfall samt rekommendationer till fortsatt arbete.</p> / <p>Volvo Aero’s aircraft engine manufacturing in Trollhättan has introduced a number of detail models into the production. As a consequence the robot cell dedicated to executing a deburring operation is in need of upgrading of both hardware and software. This report follows the development of fixture concepts that enables the robot cell to be used also for the new details. The proposals that have been developed range from the simplest to more advanced including novel functions. All the functions and concepts have gone through selection in multiple steps. The suggestions have finally been combined and evaluated with concept generation tools.</p><p>After an objective selection based on the concept scoring of six different concepts, the result can be divided into two main groups, each consisting of three concepts. The first group is a more advanced design with a need of two axes of rotation. These three concepts have several advantages when it comes to efficiency, but also obvious disadvantages when it comes to economy and production time. The second group of concepts is based on the fixture existing today. These three concepts are advantageous concerning production time and cost.</p><p>After the scoring process one main concept, judged to be the most suitable is presented more thoroughly. Finally the results as well as recommendations for continued work are discussed.</p>
46

Flygplanstillverkning : Fixturkoncept till robotgradning / Concept generation of deburring fixture for robot operation

Hansson, Anders, Kylander, Robert January 2009 (has links)
Volvo Aeros flygmotortillverkning i Trollhättan har infört ett antal nya detaljvarianter i produktionen. Detta har medfört att den robotcell som är avsedd att utföra en avgradningsoperation är i behov av uppdatering av både hårdvara och mjukvara. Denna rapport följer framtagningen av fixturkoncept som möjliggör att robotcellen kan användas även till de nya detaljerna. De förslag som arbetats fram sträcker sig från enklast möjliga till mer avancerade och nytänkande funktioner. Samtliga funktioner och koncept har genomgått gallringar i ett flertal steg. Förslagen har slutligen kombinerats och poängbedömts med konceptgenereringsverktyg till grund. Efter en objektiv poängbedömning av sex olika koncept baserad på concept scoring visar sig två huvudgrupper med tre koncept i varje. Den ena gruppen bygger på en mer avancerad konstruktion med behov av två rotationsaxlar. Dessa medför ett flertal fördelar gällande effektivitet, men även påtagliga nackdelar vad gäller ekonomiska aspekter och idrifttagandetid. Den andra gruppen av koncept baseras mer på det befintliga fixturkonceptet. Detta medför fördelar gällande idrifttagandetid och kostnader. Ett huvudkoncept som efter poängbedömningen visat sig mest lämpligt presenteras mer ingående och slutligen förs en diskussion gällande resultatets utfall samt rekommendationer till fortsatt arbete. / Volvo Aero’s aircraft engine manufacturing in Trollhättan has introduced a number of detail models into the production. As a consequence the robot cell dedicated to executing a deburring operation is in need of upgrading of both hardware and software. This report follows the development of fixture concepts that enables the robot cell to be used also for the new details. The proposals that have been developed range from the simplest to more advanced including novel functions. All the functions and concepts have gone through selection in multiple steps. The suggestions have finally been combined and evaluated with concept generation tools. After an objective selection based on the concept scoring of six different concepts, the result can be divided into two main groups, each consisting of three concepts. The first group is a more advanced design with a need of two axes of rotation. These three concepts have several advantages when it comes to efficiency, but also obvious disadvantages when it comes to economy and production time. The second group of concepts is based on the fixture existing today. These three concepts are advantageous concerning production time and cost. After the scoring process one main concept, judged to be the most suitable is presented more thoroughly. Finally the results as well as recommendations for continued work are discussed.
47

UTVÄRDERING OCH UTVECKLING AV TRANSPORTFIXTURER FÖR BAKAXLAR : / EVALUATION AND DEVELOPMENT OF TRANSPORT FIXTURES FOR REAR WHEEL AXLES

Ahlqvist, Max, Hammarström, Niklas January 2011 (has links)
Examensarbetet har genomförts i samarbete med Meritor HVS AB i Lindesberg som tillverkar fram- och bakhjulsaxlar till buss- och lastbilsindustrin. Projektet behandlar de fixturer som används vid transport av bakhjulsaxlar. Målet med arbetet var att utveckla en ny transportfixtur som passar majoriteten av deras bakaxelmodeller och som förebygger skador vid transport. Projektet har genomförts enligt metodiken systematisk konstruktion som beskrivs enligt Johannesson, Persson och Petterssons (2004). Systematisk konstruktion kan delas in i fem steg: produktspecificering, konceptgenerering, utvärdering och val av koncept, detaljkonstruktion samt slutkonstruktion. De problem som Meritor har med transportfixturerna är att de i hög grad slits och att skyddsbeläggningarna inte håller. Det finns för projektet 30 aktuella bakaxelmodeller som skall kunna transporteras med samma fixtur. Meritor använder sig av en grundfixtur och diverse nödlösningar för att kunna hantera alla modeller. De nya fixturkoncepten begränsas av de nuvarande stålrackens dimensioner och fixturernas positioner i dem. Utifrån de konceptförslag som tagits fram i arbetet, fördes de två mest lämpade koncepten vidare till slutkonstruktion. Det första konceptet, T-fixturen, bygger på den fixtur som används idag och är således ett förbättringsförslag. Förbättringarna består av en ökad anläggningsyta, bättre skyddsbeläggning samt vikt- och hållfasthetsoptimeringar. Det andra konceptet, pinnfixturen, bygger även den på samma grundfixtur men använder sig av två öglor som finns på varje axelmodell. Genom att placera axelns öglor över två pinnar i fixturen uppnås en total fixering av axeln. / This thesis has been carried out in cooperation with Meritor HVS AB in Lindesberg that manufactures front and rear wheel axles for the bus and truck industry. The project focuses on fixtures used in the transportation of rear wheel axles. The goal of the project was to develop a new transport fixture that suits the majority of rear axle models and prevents damage during transport. The project is based on the systematic design methodology described by Johannesson, Persson and Pettersson (2004). Systematic design can be divided into five stages: product specification, concept generation, concept evaluation and selection, detailed design and final design. The main issue with Meritors fixtures is that they wear out easily and that the protective coating breaks. One fixture type needs to be able to handle the 30 rear axle models relevant to this project. Meritor currently uses a basic structure combined with miscellaneous temporary solutions to handle all models. The new conceptual fixture is limited by the current steel rack, it´s dimensions and fixture positions within the construction. Based on the concept designs put forward in the work, the two most suitable concepts were brought through to final design. The first concept, the T-fixture, was based on the fixture in use today and is thus an improvement. The improvement consists of an increased contact surface, better protective coating as well as weight and strength optimizations. Concept two, the Rod fixture, is also based on the same basic fixture but uses two loops that are available on every axle model. By placing the axle loops over the two rods in the fixture, a total immobilization of the axle is achieved.
48

Åtkomststudie för robotiserad svetsning av flygmotordetalj

Blom, Johanna, Öster, Carl-Johan January 2011 (has links)
The aim of this thesis was to investigate if the robotized welding method FSW (Friction Stir Welding) could be applied for joining a rotating structure in an aero engine at Volvo Aero Corporation. FSW is expected to introduce less defects than today’s welding methods and could therefore be suitable for critical aero components. The material is the nickel based alloy Inconel 718, however a material experimentation is outside the scope of this report.The main goal of this study is to verify if the ESAB ROSIO robot based FSW-system has a suitable work space to be able to weld the rotating structure, and if the welding tool has accessibility to the joints. The FSW-process needs a rigid fixture, and a number of fix-ture concepts are presented based on a proposed weld sequence. A final fixture design is proposed, which requires a new design of the structure.The accessibility studies were performed in the robot simulations software Robot Stu-dio. This showed that the robot was unable to weld the proposed model in all areas in the original design. If the robot and the rotating structure can be redesigned the access will be achieved as shown in Robot Studio simulations.In order to be implemented in real production a number of further actions need to be taken and the result of this study can be a basis for these.
49

Brain-Computer Interface Control of an Anthropomorphic Robotic Arm

Clanton, Samuel T. 21 July 2011 (has links)
This thesis describes a brain-computer interface (BCI) system that was developed to allow direct cortical control of 7 active degrees of freedom in a robotic arm. Two monkeys with chronic microelectrode implants in their motor cortices were able to use the arm to complete an oriented grasping task under brain control. This BCI system was created as a clinical prototype to exhibit (1) simultaneous decoding of cortical signals for control of the 3-D translation, 3-D rotation, and 1-D finger aperture of a robotic arm and hand, (2) methods for constructing cortical signal decoding models based on only observation of a moving robot, (3) a generalized method for training subjects to use complex BCI prosthetic robots using a novel form of operator-machine shared control, and (4) integrated kinematic and force control of a brain-controlled prosthetic robot through a novel impedance-based robot controller. This dissertation describes each of these features individually, how their integration enriched BCI control, and results from the monkeys operating the resulting system.
50

Konstrukční návrh přípravků pro změnu výrobního postupu tlakových zásobníků Common Rail / Design of Clamping Fixtures for Common Rail Manufacturing Process Change

Macháček, Kamil January 2012 (has links)
Práce se zabývá změnou výrobního procesu výroby tlakového zásobnku system Common Rail. Předmětem práce je take návrh a úprava upínacího přípravku pro výrobu kovaných tlakových zásobníků pro obráběcí centra ELHA.

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