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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.
11

Automated generic parameterized design of aircraft fairing and windshield

Singh, Aakash Narender, Govindharajan, Vijay January 2012 (has links)
The process of design is time consuming and result oriented. There is always a better scope for any design that reduces the time with better precision. Considering this as a major factor during design process, two of the vital parts of the aircraft conceptual design are taken into account where a lot of time can be saved. Major components considered in this work are fairings for the lift generating surfaces and cockpit windshield. In this work the major inference is to reduce the time spent on the initial conceptual design. The two components designed in this work are fairings and windshield. The fairing design in this work provides a flexible template which can be used for various fuselage and wing configurations for transport aircrafts. The windshield is classified into two types in this work, flat and blend windshield. Both the type of windshields can be implemented on appropriate fuselage. Both the components are designed to be implemented in single pilot as well as double pilot aircrafts. They also have parameters which can be modified according to the user requirement. The changes in the parameters provide the change in shape, size and volume of the components. The software used for this is CATIA V5. The process is carried out using two automation methods available in CATIA namely Power-Copy and Knowledge pattern. A comparison between the effectiveness of two automation methods used in this work is performed.
12

Methodology development for parametric CAD modeling in CATIA V5 to aid simulation driven design using turbine volute as a case study

Luu, ViChi January 2015 (has links)
This report is the documentation of a master’s thesis which was conducted at Scania CV AB in Södertälje. In this study, the benefits, challenges and conditions of using parametric CAD-models for aiding CFD-simulations and performance-optimization in the product development within internal combustion engines have been assessed. The goal of the thesis included developing and proposing a methodology for design engineers at Scania which will aid them in creating parametric CAD-models which are robust, flexible, comprehensible and intelligent. The study also included assessing the benefits and pre-requisites of such methodology with both practical and theoretical approaches. The ultimate goal of this entire study was to create value for the organization by reducing lead-time in the design process while promoting the production of high quality products. A case-based approach was applied in the study in which modeling strategies resulting from practical investigations and analyzing existing methodologies were implemented on a CAD-model representing the gas-volume of a turbine volute. The chosen strategies were evaluated and subsequently documented as a part of the methodology or discarded depending on its support for the parameterization. The final methodology itself was evaluated based on the quality of the parameterized CAD-model, the time required to create the model and its compatibility to the present design process at Scania CV AB. Finally the methodology was discussed with respect to the different evaluations, and the defined research questions were discussed and answered. The results of the thesis revealed that if parametric CAD-models are made in a structured, standardized and conscious manner, they are able to be highly robust and flexible which gives the models the ability to assume a big set of different forms. The methodology is recommended to be tested in a pilot project and be implemented through internal courses at the company. It was concluded that a methodology which aids the design engineers in creating parametric CAD-models will be the key towards implementing parametric CAD-models in the company and also enabling the many benefits of parameterization, which includes reduced lead-time, enhanced component performance, increased knowledge about the component, and promotion of collaboration among engineers. It was also concluded that parametric models are best suited when the existing design freedom is big and when the time permits performance analyses via optimizations, while challenges include ensuring that the model is parameterized correctly with respect to the CFD-engineers’ wishes while taking into account the requirements from other disciplines. Therefore it is very important to establish a communication between the different engineers. Ultimately, when parametric models are established in the organization, they are recommended to be implemented eventually in both short-term and long-term projects within Scania for its beneficial properties.
13

Efficiency and Automation in the Interface between Airframe Development and Production : A study to identify and reduce time-consuming activities with focus on the methodology of In-Process Part Definition

Pettersson, Viktoria, Magnusson, Malin January 2019 (has links)
This thesis started as an initiative from one of the co-authors that previously worked at SAAB AB during summer 2018. During the summer she worked with the design process of In-process part Definition (IPPD) and an interest emerged for making it more efficient. The design process of IPPD (DPOI) is where a design article, designed in CATIA, become manufacturable and adapted for assembly. The DPOI can be seen as the interface between the department of Airframe development and Production at SAAB AB. The first step was to investigate the current DPOI and conduct a pre-study to find time-consuming activities.  The pre-study consisted of five interviews, an observational study and a time study were the aims was to collect employees' own opinions, approve a pre-defined workflow divided into twelve elements and find problem areas. Element 1.0-11.0 is tasks within the DPOI and element 12.0 is the first step in the review process called Checker. Element 4.0 and 8.0 were divided further into parallel activities where the operators in the time study performs either, e.g., E4.0 (macro) or E4.1 (manually). To find time-consuming activities a time study was performed. The authors of this thesis acted observers and clocked each element while three operators denoted A-C designed 24 IPPDs. The results from the time study showed that elements 1.0, 3.0, 4.1 and 7.0 were time-consuming and E4.1 had potential to become automated. The selection of 2-3 problems was carried out through two Weighted Sum Models (WSM) where criteria was defined and solutions was listed. Each solution was weighted to each criterion and got a total grade. The selected problems, based on the total grade, were: Documents and Combined macro. Documents and manuals for scenario 5, 6 and the entire design process of IPPD was developed to make new employees learning process more efficient. A draft macro for scenario 5 and new complete macros for scenario 1 and 6 was developed and used in the comparative study. The comparative study was conducted like the previous time study but instead the new developed macros was used to make E4.0 more efficient and eliminate E4.1. In the comparative study only E4.0 was clocked for all 24 IPPDs in the time study. The result showed that E4.0 has become average 60% more efficient for all IPPDs and the total time with the new developed macros for E4.0 vs E4.1 has become 14,3% more efficient. Problems and time-consuming activities has been found and improved. The performed comparative study shows that the DPOI can be minimized further in terms of time; there are possibilities to make more elements from the DPOI automated.
14

Fixering av Cross-beam på Fixed Caliper 22"

Ohlsson, Johan January 2009 (has links)
<p>Denna rapport behandlar mitt examensarbete som genomfördes i samarbete med Haldex</p><p>Brake AB. Haldex Brake AB håller på och utvecklare en ny generation broms åt lastbilar.</p><p>Uppdraget bestod av tre delar. Att ta fram lösningsförslag som säkerhetsställer beläggjärnets</p><p>placering i förhållande ett beläggjärn så kallad Cross-beam. Att säkerställa att bultar monteras</p><p>med rätt åtdragningsmoment på 230Nm. Den sista tredjedelen av arbetet bestod i att</p><p>presentera lösningar som helt eller delvis eliminerar oljud, när olika komponenter med spel,</p><p>slår i delar i okhuset.</p><p>I projektet har flera olika principkonstruktioner tagits fram och genom Freddy Olsson</p><p>utvärderingsmallar har sedan en primärkonstruktion utarbetats fram.</p><p>I dem andra två resterande projektdelarna belyses lösningarna väldigt generellt av den</p><p>anledningen att det kräver specialkomponenter.</p>
15

Design of Parametric Winglets and Wing tip devices : A Conceptual Design Approach

Rajendran, Saravanan January 2012 (has links)
Winglets being a small structure play an important role in reducing the induced drag in aircraft. Many types of winglets have been designed and their significance in reducing the drag is published. One of the main objectives of this master thesis work is to study about the winglet design and about their contribution in reducing induced drag. A brief overview of wing tip devices and their performance from the manufacturers as well as from airliner’s point of view are discussed. Moreover, the role of winglet in reducing the drag of commercial civil jet aircraft is studied and the percentage of drag reduction is calculated by a conceptual approach. A320 specifications are taken to perform induced drag reduction calculation with and without winglets. Indeed, the total drag count reduced with the help of winglets accounts for additional payload which will be an advantage for the aircraft operator. Reducing the process time in design is one of the important criteria for any field and hence automation with help of CAD tools is very significant in reducing time. This study also aims at developing an automated model for different types of winglets and wing tip devices with the help of CAD technology focused on reducing design time during the initial design process.  Knowledge based approach is used in this work and all the models are parameterized so each model could be varied with associated parameters. The generic model created would take different shapes and switches between different types of wing tip devices as per the user’s requirement with the help of available parameters. Knowledge Pattern (KP) approach is used to develop the automation process. User Defined Features (UDFs) are created for each type of winglet and tip devices. CATIA V5 R18 software is used to develop the models of winglets and tip devices.
16

Parametric Design: An Implementation of Bentley Systems Generative Components

Cichy, Mark Andrew January 2006 (has links)
This thesis addresses the need for flexible parametric design tools. It focuses on the implementation of a particular tool, Bentley Systems' Generative Components, by exploring features, strengths and weaknesses, and how features can be implemented in design. An exposition of Generative Components is introduced to bridge the gap between the potential and existing power of parametric tools. Through a case study of the Bahá'í Temple for South America this thesis explores the implementation of Generative Components. The exposition argues for the validity of parametric research, specifically its ability to streamline and enhance an architectural design process. <br /><br /> The topic of parametric design is further documented in a survey submitted to researchers and developers in the field of parametric research and design. The purpose of this documentation is to place the progression of parametric tools within the context of current development, initiating an open-ended discussion focusing on future research. <br /><br /> This thesis adds to the current development of parametric technology by making particular contributions to tools within the realm of parametric research. Primary contributions include array seeking scripts that search for and replace or duplicate objects, routines for nesting functions within scripts, ideological workflow development and conceptual training through practical application.
17

Fixering av Cross-beam på Fixed Caliper 22"

Ohlsson, Johan January 2009 (has links)
Denna rapport behandlar mitt examensarbete som genomfördes i samarbete med Haldex Brake AB. Haldex Brake AB håller på och utvecklare en ny generation broms åt lastbilar. Uppdraget bestod av tre delar. Att ta fram lösningsförslag som säkerhetsställer beläggjärnets placering i förhållande ett beläggjärn så kallad Cross-beam. Att säkerställa att bultar monteras med rätt åtdragningsmoment på 230Nm. Den sista tredjedelen av arbetet bestod i att presentera lösningar som helt eller delvis eliminerar oljud, när olika komponenter med spel, slår i delar i okhuset. I projektet har flera olika principkonstruktioner tagits fram och genom Freddy Olsson utvärderingsmallar har sedan en primärkonstruktion utarbetats fram. I dem andra två resterande projektdelarna belyses lösningarna väldigt generellt av den anledningen att det kräver specialkomponenter.
18

Användaranpassning av instruktioner

Karlsson, Catarina January 2008 (has links)
Detta arbete har syftat till att ta reda på vad som är viktigt att tänka på vid utformning av instruktioner för CAD-användare. Som praktikfall har en studie gjorts på Volvo IT där deras instruktioner för CAD/CAM/CAE-systemet CATIA V5 har granskats. Undersökningen mynnade ut i en användarstudie där erfarna användare av systemet fick möjlighet att diskutera den support som finns i dagsläget samt ställa krav på framtida instruktioner. Kraven som togs fram har legat till grund för riktlinjer för hur morgondagens instruktioner skulle kunna göras mer användaranpassade. Några områden som är viktiga att ta hänsyn till är bland annat: att ta tillvara på användarnas erfarenhet, involvera användarna vid framtagandet av instruktionerna, ta reda på hur instruktionenrna läses samt skapa rubrikter som underlättar informationssökning för användarna.
19

Parametric Design: An Implementation of Bentley Systems Generative Components

Cichy, Mark Andrew January 2006 (has links)
This thesis addresses the need for flexible parametric design tools. It focuses on the implementation of a particular tool, Bentley Systems' Generative Components, by exploring features, strengths and weaknesses, and how features can be implemented in design. An exposition of Generative Components is introduced to bridge the gap between the potential and existing power of parametric tools. Through a case study of the Bahá'í Temple for South America this thesis explores the implementation of Generative Components. The exposition argues for the validity of parametric research, specifically its ability to streamline and enhance an architectural design process. <br /><br /> The topic of parametric design is further documented in a survey submitted to researchers and developers in the field of parametric research and design. The purpose of this documentation is to place the progression of parametric tools within the context of current development, initiating an open-ended discussion focusing on future research. <br /><br /> This thesis adds to the current development of parametric technology by making particular contributions to tools within the realm of parametric research. Primary contributions include array seeking scripts that search for and replace or duplicate objects, routines for nesting functions within scripts, ideological workflow development and conceptual training through practical application.
20

Användaranpassning av instruktioner

Karlsson, Catarina January 2008 (has links)
<p> </p><p>Detta arbete har syftat till att ta reda på vad som är viktigt att tänka på vid utformning av instruktioner för CAD-användare. Som praktikfall har en studie gjorts på Volvo IT där deras instruktioner för CAD/CAM/CAE-systemet CATIA V5 har granskats. Undersökningen mynnade ut i en användarstudie där erfarna användare av systemet fick möjlighet att diskutera den support som finns i dagsläget samt ställa krav på framtida instruktioner. Kraven som togs fram har legat till grund för riktlinjer för hur morgondagens instruktioner skulle kunna göras mer användaranpassade.</p><p>Några områden som är viktiga att ta hänsyn till är bland annat: att ta tillvara på användarnas erfarenhet, involvera användarna vid framtagandet av instruktionerna, ta reda på hur instruktionenrna läses samt skapa rubrikter som underlättar informationssökning för användarna.</p><p> </p>

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