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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.
1

Kostnadsbesparingar på EM7 : Omkonstruktioner för billigare tillverkning

Thunell, Björn January 2012 (has links)
This thesis describes how a cost reduction project was done on the Packsize ondemand packing machine EM7. The cost reduction was achieved by making minorredesigns of the EM7.The project began by studying the EM7´s structure and function by working on itsassembly line. A short literature study on the subject Design for Manufacturing wasalso done.By working on the assembly line and by speaking with staff from production anddevelopment departments, a number of ideas for reducing manufacturing costs arose.Estimations of the potential cost reduction size for each proposal were done incollaboration with vendors and the purchasing department. Based on the size of the cost reduction, technical risk, impact on the assembly lineand the development time the various proposals were ranked. The two highestranked proposals were selected for further development towards finished solutions.One of the ideas that were selected to develop in to a finished solution meant thatsome of the pneumatic valves were replaced with others. Most of the mechanicalfeatures on the EM7 are operated by pneumatic cylinders, and they are controlled bythe valves. The valves in use today have very fast switching times which makes themrelatively expensive. By replacing the valves with valves that have higher airflow butlonger switch times, costs are reduced through a lower purchase price of the valves.Thanks to the higher airflow this can be done without affecting the EM7´sperformance.The second proposal was selected because it reduces assembly time. By using rivetsfor the assembly of the EM7’s z-fold infeed system, assembly time can be reducedsignificantly.The total cost savings per machine is between 960SEK to 2620SEK depending on theequipment choices.
2

Reduction of Printed Circuit Card Placement Time Through the Implementation of Panelization

Tester, John T. 09 October 1999 (has links)
Decreasing the cycle time of panels in the printed circuit card manufacturing process has been a significant research topic over the past decade. The research objective in such literature has been to reduce the placement machine cycle times by finding the optimal placement sequences and component-feeder allocation for a given, fixed, panel component layout for a given machine type. Until now, no research has been found which allows the alteration of the panel configuration itself, when panelization is a part of that electronic panel design. This research will be the first effort to incorporate panelization into the cycle time reduction field. The PCB circuit design is not to be altered; rather, the panel design (i.e., the arrangement of the PCB in the panel) is altered to reduce the panel assembly time. Component placement problem models are developed for three types of machines: The automated insertion machine (AIM), the pick-and-place (PAPM) machine, and the rotary turret head machine (RTHM). Two solution procedures are developed which are based upon a genetic algorithm (GA) approach. One procedure simultaneously produces solutions for the best panel design and component placement sequence. The other procedure first selects a best panel design based upon an estimation of its worth to the minimization problem. Then that procedure uses a more traditional GA to solve for the component placement and component type allocation problem for that panel design. Experiments were conducted to discover situations where the consideration of panelization can make a significant difierence in panel assembly times. It was shown that the PAPM scenario benefits most from panelization and the RTHM the least, though all three machine types show improvements under certain conditions established in the experiments. NOTE: An updated copy of this ETD was added on 09/17/2010. / Ph. D.
3

A Plastic Injection Molding Part Feature Extractor and Design Advisory System

James, Sagil 12 April 2010 (has links)
No description available.
4

DFM/A-metod för integrerade strukturdelar i kolfiberkomposit : Vidareutveckling av metodik för SAAB Aerostructures / DFM/A method for integrated structures of carbon fiber reinforced plastic : Further development of methodology for SAAB Aerostructures

Jensen, Jonas, Nilsson, Sara January 2015 (has links)
Kolfiberkompositer är ett av de materialsom utvecklas snabbast just nu. Analogt med att materialet blir billigare och börjar användas i större utsträckning av flygindustrin utvecklas också tillverkningsmetoder för att följa framstegen. Hur material och tillverkningsmetoder sätter krav och påverkar en produkts utformning och prestanda kan vara svårt att definiera. I detta examensarbete har en Design for Manufacturing och Assembly (DFM/A)-metod utvecklats för att under hela produktutvecklingsprocessen kunna ta hänsyn till produktionsaspekter. DFM/Ametoden är framtagen åt Saab Aerostructures med hänsyn till de material som används, deras existerande produktionsprocesser och den produktutvecklingsprocess som finns på företaget. Utifrån litteratur- och fallstudier har en DFM/A-metod som kallas Metod 2015 (M2015) utvecklats. Metoden innehåller en arbetsprocess, konstruktionsriktlinjer samt stödjande DFM/Averktyg. Genom att i hela utvecklingsprocessen ta hänsyn till produktionsaspekter är detta arbetssätt anpassat för att underlätta utveckling av kolfiberkompositkomponenter på Saab. Utöver själva metoden i sig finns allt material som behövs för användning av M2015 sammanställt i en manual som i första hand riktar sig till konstruktören. Genom att skapa en bättre förståelse för produktionsaspekterna hos en konstruktion och tillhandahålla rätt verktyg kan DFM/A-metoden bidra till flera positiva effekter. Användandet av M2015 bör leda till produkter av kolfiberkomposit som är lättare att tillverka vilket i sin tur också bör minska onödiga kostnader, ge högre kvalitet och kortare ledtider. Införandet ställer dock också krav på Saab för att dessa målsättningar ska kunna uppnås. / Carbon fiber reinforced plastic (CFRP) is one of the fastest developing materials right now. Analogously to the material becoming cheaper and being used more widely in the aerospace industry the manufacturing methods have developed to follow the progress. How material and manufacturing method change the requirements and affect a product's design and performance can be hard to determine. This degree project has developed a Design for Manufacturing and Assembly (DFM/A) method to easier take into consideration the production process throughout the product development. The DFM/A method is developed for Saab Aerostructures and is based on their materials, production process and product development process. By studying literature and performing case studies a DFM/A method called Method 2015 (M2015) was developed. The method includes a work procedure, design guidelines and supporting DFM/A tools. By considering the production aspects throughout the development process this method of operation facilitate the development of CFRP products at Saab. In addition to the method itself the materials needed to use M2015 is compiled in a manual for the designer. By creating a better understanding of the production aspects of a design and providing the right tools the DFM/A method can contribute to several positive effects. The use of M2015 should lead to CFRP products that are easier to produce which in turn should minimize unnecessary costs, raise the quality and shorten lead times. However, the implementation of M2015 at Saab also creates demands to reach these targets
5

Design for Manufacturing : för produktionsanpassad konstruktion på Volvo Aero

Kämpe, Malin, Albertson, Peter January 2011 (has links)
Målet med examensarbetet var att skapa ett verktyg för insamling av erfarenhetsdata för produktutvecklingsprocessen. Den skall vara användbar för att bidra till ett systematiskt arbetssätt för produktionsanpassad konstruktion på Volvo Aero Corporation. Det skapade verktyget för insamlande av erfarenhetsdata skall bidra till att produktivitet och producerbarhet kan förbättras på kommande koncept och konstruktioner. En förstudie har genomförts på företaget under hösten 2010 vilket ligger till grund för det beskrivna problemet i examensarbetet. Arbetet avgränsades till att utveckla en struktur för hur metod och erfarenhet skall struktureras och en testversion av verktyget togs fram för utvärdering. Efter samråd med den handledande Verksamhetsutvecklingsgruppen, VU-gruppen, från avdelning 9931 Projekt-, Koncept- och Tillverkningsledning, beslutades att examensarbetet skulle avgränsas ytterligare till insamling av diametermått på komponenten Diffuser Case på Volvo Aero. Under arbetets gång har återkommande möten veckovis infunnit sig med den utvalda VU-gruppen där också chefen från avdelningen och handledaren från företaget medverkat. Utgångspunkten för verktygets skapande var nuvarande produktion och dess information som finns att tillhandahålla. Det Design for Manufacturing-verktyg som skapats i Microsoft Excel samlar information från flera olika system och källor på Volvo Aero och presenterar denna information på ett pedagogiskt vis. Verktygets struktur har genom samråd med utvald VU-grupp tagits fram och de 35 kolumner som finns att fylla på med information är indelade i tre olika grupper för att erhålla ett systematiskt och pedagogiskt upplägg: basfakta, duglighet och kostnad samt bearbetningstid. Genom denna indelning erhålls en stigande detaljeringsgrad från vänster till höger i verktyget som ett medel för användaren att skapa ett tydligt och strukturerat arbetsätt. Kunskap, information och data som insamlas representerar uppgifter om kravnummer företaget serieproducerar idag. Verktyget skall med tiden fyllas på med fler uppgifter från strategiskt utvalda komponenter vilka stämmer överens med den inriktning företaget valt att gå i utvecklingen av nya komponenter. / The purpose of the Bachelor’s Thesis was to create a tool for the gathering of experience data for the product development process. It should contribute to a systematic operation approach at Volvo Aero Corporation. It should also contribute to improve productivity and producibility on future concepts. The problem described in the Bachelor’s Thesis is based on a pre-study performed at the company during the autumn 2010. The general task was defined as develop a structure for re-use of manufacturing experience and to create a test version of the tool for evaluation. After consultation with the selected Business Development-group from department 9931 Project-, Concept- and Manufacturing-leaders, the task was limited to gathering information of diameter dimensions from the Diffuser Case component at Volvo Aero. The creation of the tool had its starting-point in current production and the information available there. The Design for Manufacturing-tool has been created in Microsoft Excel and it’s developed in a way making it possible to gather and present information from different systems and sources. The tool presents the information in a pedagogical way that makes it user-friendly. The structure of the tool has been developed in consultation with the Business Development-group and the 35 columns of information is classified in three different groups: basic facts, capability and cost, operation time. By this classification the information level of detail increases from left to right which enables a more structured and systematic way of working. The knowledge, experience and data gathered represent information about the requirements the company currently produces. Over time, the Design for Manufacturing-tool is to be filled with more information from strategically chosen components which coincide with the direction the company has chosen for the development of new components.
6

Une méthode d'optimisation multicritère pour le Design For Manufacturing : application aux portes d'avion / A multicriteria optimization method for Design for Manufacturing : application to an aircraft door

Fortunet, Charles 30 November 2017 (has links)
Actuellement, le marché aéronautique est en constante augmentation. Pour faire face à cela, les avionneurs doivent se restructurer et revoir les processus de fabrication des pièces. En effet, il est nécessaire d’augmenter les cadences et réduire les prix tout en conservant les performances des pièces (poids et résistance mécanique). Cependant, ces trois objectifs sont contradictoires et un compromis est difficile à trouver. Ces travaux de thèse abordent cette problématique dans le cadre du CORAC. Ils proposent une manière originale d’optimiser une pièce de structure aéronautique qui vise à développer une nouvelle approche de la conception de pièces et de processus de fabrication pour tendre vers des solutions de compromis performantes. Pour ce faire, une méthodologie multicritère en trois étapes est proposée. D’abord, l’expertise industrielle est formalisée afin de formuler le problème mathématiquement. Ensuite, un algorithme génétique est utilisé afin de déterminer une population de solutions dont les performances sont placées sur un front de Pareto.Enfin, une étape de choix parmi la population finale prenant en compte le contexte industriel est mise en place. Cette méthodologie est appliquée à une porte d’avion moyen-courrier fabriquée par matriçage puis usinage. Dans ce cas, elle permet de choisir la solution la plus adaptée au contexte industriel parmi mille solutions de compromis. / Nowadays, the aeronautical market grows constantly. To face this, aircraft industry has to restructure and the manufacturing processes must be revised. Indeed, production rate must increase and manufacturing cost decrease while keeping the performances of the parts (weight and mechanical resistance). These objectives are contradictory and compromises must be found. This thesis broaches this problematic in relation to the CORAC. A novel method to optimize an aeronautical structural part and its manufacturing process is developed to tend toward performing compromise solutions. To do so, a three steps multi-criteria method is proposed. First, the industrial expertise is formalized to mathematically express the problem. Then, a genetic algorithm is used to determine a population in which every solution is located on a single Pareto front. At least, a decision step is set up to find the best solution in the population considering the industrial environment of the part. This methodology is applied to an aircraft door manufactured by forging and machining. In this case, it allows choosing the solution that fit the most the industrial environment within a one thousand solutions’ population.
7

DFM – Weldability analysis and system development

Pabolu, Venkata Krishna Rao January 2015 (has links)
This thesis work is mainly focused on the processes involved in manufacturing of aircraft engine components. The processes are especially about welding and welding methods. The basics of welding and the thesis support has been taken from the GKN Aerospace Sweden AB, a global aerospace product supplier.  The basic objective of this thesis work is to improve the usability of an automation system which is developed for evaluating the weldability of a part. A long run maintainability aspect of this automation system has been considered. The thesis work addresses the problems arising during the usage of a computerised automated system such as process transparency, recognisability, details traceability and other maintenance aspects such as maintainability and upgradability of the system in the course of time. The action research methodology has been used to address these problems.  Different approaches have been tried to finding the solution to those problems. A rule based manufacturability analysis system has been attempted to analyse the weldability of a component in terms of different welding technics. The software “Howtomation” has been used to improve the transparency of this analysis system. User recognisability and details tractability have been taken into account during the usage of a ruled based analysis system. The system attributes such as maintainability, upgradability, adaptiveness to modern welding methods has been addressed. The system suitability for large scale analysis has been considered.
8

Design for manufacturing with advanced lithography

Yu, Bei 28 October 2014 (has links)
Shrinking the feature size of very large scale integrated circuits (VLSI) with advanced lithography has been a holy grail for the semiconductor industry. However, the gap between manufacturing capability and the expectation of design performance becomes critically challenged in sub-16nm technology nodes. To bridge this gap, design for manufacturing (DFM) is a must to co-optimize both design and lithography process at the same time. DFM for advanced lithography could be defined very differently under different circumstances. In general, progress in advanced lithography happens along three different directions: (1) New patterning technique (e.g., layout decomposition for different patterning techniques); (2) New design methodology (e.g., lithography aware standard cell design and physical design); (3) New illumination system (e.g., layout fracturing for EBL system, stencil planning for EBL system). In this dissertation, we present our research results on design for manufacturing (DFM) with multiple patterning lithography (MPL) and electron beam lithography (EBL) addressing these three DFM research directions in advanced lithography. For the research direction of new patterning technique, we study the layout decomposition problems for different patterning technique and explore four important topics: (1) layout decomposition for triple patterning; (2) density balanced layout decomposition for triple patterning; (3) layout decomposition for triple patterning with end-cutting; (4) layout decomposition for quadruple patterning and beyond. We present the proof that triple patterning layout decomposition is NP-hard. Besides, we propose a number of CAD optimization and integration techniques to solve different problems. For the research direction of new design methodology, we will show the limitation of traditional design flow. That is, ignoring triple patterning lithography (TPL) in early stages may limit the potential to resolve all the TPL conflicts. We propose a coherent framework, including standard cell compliance and detailed placement, to enable TPL friendly design. Considering TPL constraints during early design stages, such as standard cell compliance, improves the layout decomposability. With the pre-coloring solutions of standard cells, we present a TPL aware detailed placement where the layout decomposition and placement can be resolved simultaneously. In addition, we propose a linear dynamic programming to solve TPL aware detailed placement with maximum displacement, which can achieve good trade-off in terms of runtime and performance. For the EBL illumination system, we focus on two topics to improve the throughput of the whole EBL system: (1) overlapping aware stencil planning under MCC system; (2) L-shape based layout fracturing for mask preparation. With simulations and experiments, we demonstrate the critical role and effectiveness of DFM techniques for the advanced lithography, as the semiconductor industry marches forward in the deeper sub-micron domain. / text
9

USINAGE 5 AXES DE SURFACES GAUCHES CARACTÉRISÉES PAR UN CRITÈRE D'ÉTAT DE SURFACE ADAPTATIF.

Breteau, Thomas 05 November 2010 (has links) (PDF)
Ce travail, réalisé dans le cadre d'une thèse Allocation Couplée et un contexte inter-laboratoires fort : IRCCyN – IRENav – IFMA offrant de multiples ressources en productique et en hydrodynamique, vise à améliorer le processus de réalisation des hélices marines. Certaines des spécifications géométriques établies durant la conception perdent définitivement, lors de l'étape de définition de la stratégie de fabrication en finition, leur caractère fonctionnel au travers de leur traduction en paramètres liés à la machine d'usinage. Cette étude vise à proposer une alternative au polissage en renforçant les liens fonctionnels entre les propriétés de l'hélice et les paramètres géométriques des opérations de fraisage. La première partie du travail est consacrée à l'étude du processus de conception et de réalisation ainsi qu'au cycle de vieillissement des hélices marines. Les trajectoires d'usinage sont généralement obtenues par post-traitement du modèle numérique créé en C.A.O. ; passer directement des lois hydrodynamiques au trajet outil permet de mieux répondre aux exigences fonctionnelles des propulseurs marins. Ainsi des critères multiphysiques doivent être à la source de la spécification de l'état de surface, du format d'interpolation support des trajectoires et, dans le cadre d'une approche générique du processus d'usinage, du choix de l'ensemble des intervenants du processus de réalisation des hélices. Dans un second temps les relations entre les différentes activités du processus de fabrication des hélices sont restructurées et de nouvelles liaisons sont proposées entre les domaines dits « fonctionnel », « virtuel » et « physique » pour prendre en compte des contraintes fonctionnelles et ainsi aboutir à la mise en place d'un nouveau concept de génération de trajectoires d'usinage. Les lignes de frottements, signature hydrodynamique de l'hélice, sont suggérées pour supporter les trajectoires d'usinage. La complexité de ces données d'une part et celle de la géométrie hélice d'autre part nécessitent le développement d'une nouvelle stratégie de génération de trajectoires d'usinage. Ainsi, basés sur le formalisme de Bézier, des algorithmes d'interpolation sont proposés pour aboutir à des trajectoires continues au bord d'attaque, contrainte fonctionnelle incontournable et, chose essentielle, exploitables en usinage. Le passage par le bord d'attaque, lieu où la cavitation ne doit pas apparaître sous peine de se propager à l'ensemble de la pale, est l'objet de toutes les attentions. Les contraintes fonctionnelles insuffisantes en cet endroit sont, dans le cadre d'une approche multimétier, suppléées par des contraintes géométriques et des contraintes liées à la cinématique du centre d'usinage. Le trajet outil étant déterminé, une analyse de sa pertinence hydrodynamique est menée ; un découpage de la pale en zones d'application pertinente de la méthode est défini. Suite à cela, un modèle d'hélice de patrouilleur P400 de la Marine nationale est retenu comme cas d'étude. A partir de celui-ci, une étude expérimentale en bassin est mise en place en vue d'analyser, par comparaison avec une pale d'hélice étalon polie miroir, les effets de stries d'usinage orientées sur le comportement du fluide au voisinage d'une pale usinée selon la stratégie développée. Un fluide différent de celui d'évolution et une caméra rapide sont utilisés pour observer les modifications de comportement du fluide dues à l'état de surface dirigé. Les résultats de la campagne d'essais, qui reposent sur les techniques de traitement d'images, sont détaillés et analysés pour conclure sur les apports de la méthode en terme de coût et de temps de fabrication.
10

Zero Tolerance Program : A strategic approach to reduce operational cost and improve quality levels

Pettersson, Anna-Lena January 2010 (has links)
<p>For a company to be competitive today, one way is to create a natural feedback loop from the production department to the design department with information regarding the production systems ability to deliver a finished component. The purpose with this feedback loop is to create respect for tolerances and to more design for manufacturing and assembly. The studied company in this thesis work developed a quality program to reach a spiral of continuous improvements to reduce cost of poor quality (CoPQ) and to reach an improved quality level (PPM). The object of this work was to test and improve the quality program called The Zero Tolerance Program. Delimitations were made when the work was started and ongoing which led to that the impact on PPM could not be studied. The connection to CoPQ was difficult to obtain and could only be proved theoretically, not practically, due to the short timetable.</p><p>During the short amount of time the right root cause could not be found. The thesis work findings came to a number of identified Measurable Success Criteria and requirements which must be in place for the further progress of The Zero Tolerance Program.</p> / PREPARE

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