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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

Advanced monitoring system for bolted connections in vehicle construction

Buchmann, Macro January 2010 (has links)
Bolted connections where used from the beginning of vehicle construction for joining two or more parts. The reliability of bolted connections is still a major problem. The objective of this research thesis is focused on an advanced monitoring system for bolted connections in vehicle construction. A mechanical “vibrating test bench”, which was developed by the aeronautical engineer Mr. Junkers, is being adapted, to suite the requirements of the automotive industry. It is designed according to DIN 65151 standards. The bolted connection is tightened to a specific torque to achieve the required preload forces and then exposed to an oscillating elastic shear force. The preload force and their loss are measured in relation to the number of load cycles. The ideal locking mechanism would be, if no settling occurs. Realistic in practice is the remaining of a sufficient preload force which doesn’t decry with time. The aim of this thesis is, to gain knowledge that will assist in the future control of the bolt locking procedure. The test bench can be used to verify the clamping capability of a bolted connection. With the dynamic computer-aided test system it will also be possible to test critical bolted joints and their safety, which reduces the probability of costly product recalls, or even severe cases of failure.
12

Design of a low-cost autonomous guided cart for material handling

Cawood, Gareth James January 2015 (has links)
This dissertation covers the design and manufacture of an autonomous guided cart (AGC) for use in the material handling industry. General Motors South Africa (GMSA) requires a low-cost AGC for use in their Struandale plant. A budget of R35 000 per unit was proposed. The researcher, in collaboration with staff at GM, compiled a list of engineering requirements for the AGC. After research into the unique problems of the project, an examination of a previous design attempt by staff of GM Thailand, the researcher developed a new design, the subject of this report. Different solutions for each design problem were investigated before the design was finalised. A three-wheeled vehicle was designed making use of two motors in a differential-drive setup to control motion. Navigation is via a line-following mechanism, using an induction sensor-array in conjunction with a pre-laid metallic strip. To aid the design, the system was modelled to understand the different control elements at play. The researcher developed software for several aspects of the design: for the PLC controlling the system and motors; for a microcontroller that communicates with the PLC and a wireless module; for a computer server that communicates with a second wireless device, receiving information from the PLC; and a web interface to view this information. These form the SCADA integration of the project. The final product meets the GMSA specifications. It is a robot capable of towing a trolley of mass not exceeding 350 kg. While the robot is able to navigate a pre-laid route, it cannot reliably stop at marked locations. It is possible to monitor the system via a web-interface. The robot is capable of operating for an entire 8-hour shift before the batteries need to be recharged. The total cost of the prototype was R26 340.
13

Automotive engine tuning using least-squares support vector machines and evolutionary optimization

Li, Ke January 2012 (has links)
University of Macau / Faculty of Science and Technology / Department of Electromechanical Engineering
14

Universal design in automobiles : an investigation into simulators for differently abled drivers

Coetzee, Gerhardus Johannes January 2016 (has links)
Thesis (MTech (Industrial Design))--Cape Peninsula University of Technology, 2016. / Simulators are used for many different purposes, among them physical rehabilitation and the training of differently abled learner-drivers. In South Africa, however, the extent of the latter type of simulators is limited to paraplegic learner-drivers only. The reason is that locally sourcing the necessary equipment to adapt commercial simulators for the training of differently abled learner-drivers presents a problem. The concept of Universal Design stipulates that as many individuals as possible should be able to use a particular product. Consequently, a simulator for differently abled learner-drivers should accommodate as many such persons as possible. However, applying Universal Design in the area of design researched for the present dissertation adds further complexity due to the unique nature of the physical limitations experienced by individuals. A differently abled driver puts an extreme constraint on the design of a product - and becomes a limiting user. Nevertheless, this dissertation adopts a Universal Design approach to investigate the possibility of designing such a simulator in South Africa, as well as its viability. A limiting user was included in the research to represent the bigger differently abled community. Field research was carried out by implementing a Participatory Design process. Furthermore, a team was selected according to a Meta-Design mind-set, including professionals from engineering, clinical psychology and occupational therapy. The leader and researcher was an industrial designer.
15

A control strategy for the power system of a hybrid vehicle

Furrutter, Marco Klaus 24 October 2012 (has links)
M.Ing. / The increase in awareness of the environmental problems resulting from emissions released from vehicles have forced governments and car manufactures to invest more time in to the designing a vehicle that is an alternative to petrol driven vehicles. This dissertation aims to introduce a control strategy to manage the flow of energy of different power sources that may be found on a vehicle. Hybrid vehicles are a possible solution to reducing carbon emissions that play a part in global warming. In this dissertation, di erent hybrid vehicles are de ned and their components discussed in detail. The possibility of more than one energy source to power the vehicle introduces more exibility in terms of the drivetrain but this increases the complexity of the energy control management. The goal is to optimize the energy control management to reduce fuel consumption and therefore reduce emissions. Operating procedures for the various hybrid con gurations are discussed. Simulations of the Energy Management System of the hybrid electric vehicle are used to develop the control optimization algorithm. Various control optimization procedures are discussed. Satisfactory results from the simulations allow the implementation of the hybrid onto a platform entered into the South African Solar Challenge 2010, which covered a distance of 4000 km. The Energy Management system selected for the parallel hybrid electric vehicle demonstrated fuel savings, which meant a reduction in emissions, which is the goal of any hybrid vehicle. Further investigations include more intelligent controllers to adjust the parameters of the energy management controller to allow for adaptation to various driving conditions, e.g. urban and motorway driving.
16

Integrated machine learning techniques with application to adaptive decision support system for automotive engineering

Vong, Chi Man January 2005 (has links)
University of Macau / Faculty of Science and Technology / Department of Computer and Information Science
17

Scheduling projects in operating systems: an application on assembly line balancing / Programação de projetos em sistemas em operação: uma aplicação em balanceamento de linhas de montagem

Sikora, Celso Gustavo Stall 19 April 2017 (has links)
Fundação Araucária; RENAULT; Seti / A Pesquisa Operacional investiga as (melhores) formas de se configurar e coordenar sistemas ou operações usando técnicas de otimização. Geralmente, a otimização de um sistema é modelado com base no estado final almejado. Porém, como atingir ou implementar tal estado final em sistemas é pouco retratado na literatura. Esta dissertaçãode mestrado propõe uma nova classe de problema de otimização: a programação das operações entre o estado inicial e o final de um sistema, o Problema de Implementação. A programação das operações é especialmente importante para linhas de montagem. A indústria automobilística é fortemente baseada em linhas de produção que podem ser usadas até 24 horas por dia. Assim, as oportunidades de intervenções para mudar ou otimizar o sistema produtivo são poucas. As condições de implementação aplicadas ao balanceamento de linhas produtivas são discutidas, e as características observadas resultam no proposto Problema de Implementação de Linhas de Montagem (PILM). Na dissertação, um guia de modelagem baseado em Programação Linear Inteira Mista (PLIM) é desenvolvido para a formulação de diversas variações do Problema de Implementação. As instruções de modelagem são usadas para desenvolver um conjunto de modelos PLIM para o Problema de Implementação de Linhas de Montagem. Para a obtenção de resultados, um conjunto de instâncias é proposto. Assim, uma análise de sensibilidade em função de cada um dos parâmetros formadores das instâncias é realizada. As formulações são comparadas, junto com as diferentes formas de apresentar e resolver o problema. Ademais, um método de decomposição é usado para resolver um problema industrial real. A modelagem mostrase correta para a divisão da implementação de mudanças em linhas de montagem. Os resultados mostram que a divisão do esforço de implementação resulta em apenas poucas mudanças a mais (cerca de 7% para os casos pequenos e médios) comparadas com a implementação em uma fase. A possibilidade de programar a implementação em etapas menores aumenta a aplicabilidade de projetos, que, de outra forma, requeririam grande paradas de produção. / Operations Research investigates the (best) ways to configure and coordinate systems or operations with optimization procedures. Usually, the optimization of a system is modeled based on the aimed final configuration. However, little is published about how to reach or implement such optimal configurations in the systems. This master thesis proposes a new class of optimization problem: a scheduling of operations between initial and final states of a system, the Implementation Problem. The scheduling of operations is especially important to assembly lines. The automotive industry strongly relies on production lines that can operate 24 hours a day. Thus, the intervention opportunities to change or optimize the production system are very few. The implementation conditions of balancing on assembly lines are discussed, and the observed characteristics result in the proposal of the Assembly Line Implementation Problem (ALIP). The master thesis proposes a Mixed-Integer Linear Programming (MILP) modeling guide for the formulation of several variations of Implementation Problems. The modeling instructions are used to develop a set of MILP models for the Assembly Line Implementation Problem. For the results, a dataset is proposed and a sensitivity analysis on each of the consistent parameters of the dataset is performed. The proposed formulations are compared, along with the different forms of presenting and solving the problem. Furthermore, a decomposition method is used to solve a real-world industrial problem. The modeling correctly represents the division of the implementation of changes in assembly lines. The results show that the division of the effort in multiple stages only need a few more changes (around 7\% for the small and medium cases) comparing to a straightforward implementation. The possibility of scheduling the implementation in smaller steps increases the applicability of projects that otherwise would require a large system's stoppage time.
18

Scheduling projects in operating systems: an application on assembly line balancing / Programação de projetos em sistemas em operação: uma aplicação em balanceamento de linhas de montagem

Sikora, Celso Gustavo Stall 19 April 2017 (has links)
Fundação Araucária; RENAULT; Seti / A Pesquisa Operacional investiga as (melhores) formas de se configurar e coordenar sistemas ou operações usando técnicas de otimização. Geralmente, a otimização de um sistema é modelado com base no estado final almejado. Porém, como atingir ou implementar tal estado final em sistemas é pouco retratado na literatura. Esta dissertaçãode mestrado propõe uma nova classe de problema de otimização: a programação das operações entre o estado inicial e o final de um sistema, o Problema de Implementação. A programação das operações é especialmente importante para linhas de montagem. A indústria automobilística é fortemente baseada em linhas de produção que podem ser usadas até 24 horas por dia. Assim, as oportunidades de intervenções para mudar ou otimizar o sistema produtivo são poucas. As condições de implementação aplicadas ao balanceamento de linhas produtivas são discutidas, e as características observadas resultam no proposto Problema de Implementação de Linhas de Montagem (PILM). Na dissertação, um guia de modelagem baseado em Programação Linear Inteira Mista (PLIM) é desenvolvido para a formulação de diversas variações do Problema de Implementação. As instruções de modelagem são usadas para desenvolver um conjunto de modelos PLIM para o Problema de Implementação de Linhas de Montagem. Para a obtenção de resultados, um conjunto de instâncias é proposto. Assim, uma análise de sensibilidade em função de cada um dos parâmetros formadores das instâncias é realizada. As formulações são comparadas, junto com as diferentes formas de apresentar e resolver o problema. Ademais, um método de decomposição é usado para resolver um problema industrial real. A modelagem mostrase correta para a divisão da implementação de mudanças em linhas de montagem. Os resultados mostram que a divisão do esforço de implementação resulta em apenas poucas mudanças a mais (cerca de 7% para os casos pequenos e médios) comparadas com a implementação em uma fase. A possibilidade de programar a implementação em etapas menores aumenta a aplicabilidade de projetos, que, de outra forma, requeririam grande paradas de produção. / Operations Research investigates the (best) ways to configure and coordinate systems or operations with optimization procedures. Usually, the optimization of a system is modeled based on the aimed final configuration. However, little is published about how to reach or implement such optimal configurations in the systems. This master thesis proposes a new class of optimization problem: a scheduling of operations between initial and final states of a system, the Implementation Problem. The scheduling of operations is especially important to assembly lines. The automotive industry strongly relies on production lines that can operate 24 hours a day. Thus, the intervention opportunities to change or optimize the production system are very few. The implementation conditions of balancing on assembly lines are discussed, and the observed characteristics result in the proposal of the Assembly Line Implementation Problem (ALIP). The master thesis proposes a Mixed-Integer Linear Programming (MILP) modeling guide for the formulation of several variations of Implementation Problems. The modeling instructions are used to develop a set of MILP models for the Assembly Line Implementation Problem. For the results, a dataset is proposed and a sensitivity analysis on each of the consistent parameters of the dataset is performed. The proposed formulations are compared, along with the different forms of presenting and solving the problem. Furthermore, a decomposition method is used to solve a real-world industrial problem. The modeling correctly represents the division of the implementation of changes in assembly lines. The results show that the division of the effort in multiple stages only need a few more changes (around 7\% for the small and medium cases) comparing to a straightforward implementation. The possibility of scheduling the implementation in smaller steps increases the applicability of projects that otherwise would require a large system's stoppage time.
19

Driver attention and behaviour monitoring with the Microsoft Kinect sensor

Solomon, Cleshain Theodore 11 1900 (has links)
Modern vehicles are designed to protect occupants in the event of a crash with some vehicles better at this than others. However, passenger protection during an accident has shown to be not enough in many high impact crashes. Statistics have shown that the human error is the number one contributor to road accidents. This research study explores how driver error can be reduced through technology which observes driver behaviour and reacts when certain unwanted patterns in behaviour have been detected. Finally a system that detects driver fatigue and driver distraction has been developed using non-invasive machine vision concepts to monitor observable driver behaviour. / Electrical Engineering / M. Tech. (Electrical Engineering)
20

Uma abordagem interativa para auxiliar no diagnóstico automotivo / An interactive approach to assist automotive diagnostic

Oliveira, Leonardo Presoto de 21 September 2017 (has links)
Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná / Este trabalho tem como objetivo desenvolver uma abordagem para auxiliar as montadoras na obtenção de informações sobre os problemas e falhas que ocorrem nos veículos durante o seu uso pelos motoristas, relacionando os dados obtidos com a leitura da telemetria do veículo, assim como as percepções do motorista sobre uma determinada falha. A exploração de técnicas que auxiliam o diagnóstico automotivo é um problema a ser discutido na engenharia. As técnicas de diagnóstico devem fornecer suporte à grande gama de sistemas que surgirão nos próximos anos. Assim, é possível também utilizar a conectividade que os celulares e veículo dispõem na atualidade, com o intuito de evoluir o produto oferecido e melhorar a experiência do cliente enquanto dirige. A inclusão do cliente no processo de diagnóstico, visa permitir que os projetistas identifiquem pontos que podem ser melhorados no carro, mesmo que não apresentem erro aparente. A opinião do cliente pode ser considerada, uma vez que ele é incluído no processo como um novo “sensor" (o mais inteligente e importante de todos) capaz de reportar suas percepções. Considerando este fato, a motivação deste trabalho se encontra em: (i) Procurar alternativas para aplicar de maneira eficiente a conectividade dos veículos no processo de diagnóstico; (ii)Permitir que as montadoras possam obter informações mais concretas dos veículos que comercializam. O objeto é fornecer um sistema de interface entre o usuário e o carro auxiliando a realização dos diagnósticos preventivos mais completos do que apenas usando a telemetria. Neste projeto busca-se que haja uma interação maior com o motorista, e que a experiência das montadoras possa entrar no processo de diagnóstico. Mesmo que o cliente não tenha tanta intimidade com o funcionamento do veículo, o sistema deve orientar o motorista no processo. A entrada de dados do cliente é realizada por texto ou comando de voz. Para a análise desta entrada de dados do cliente foi realizado um estudo de mineração de dados em bases que a montadora já possuía. Estas bases são entrevistas telefônicas nas quais a montadora pergunta ao cliente problemas percebidos no carro, e então as respostas são transcritas para a base. O estudo de mineração de dados foi realizado para a criação do classificador que é responsável por receber os dados de entrada do cliente e classifica-lo em um determinado problema ligado à multimídia ou relacionado ao motor do veículo. O software contido no celular será responsável por solicitar ao sistema de sensores do veículo as leituras necessárias para que o cliente obtenha as informações que deseja. Foi realizado um experimento no qual analistas de diagnóstico responderam a um questionário que buscava analisar se o sistema proposto realmente influenciava no processo de diagnóstico, fazendo com que a solução dos problemas no veículo seja realizada em menos etapas, se comparado com o processo atual. Os resultados mostraram que a abordagem diminuiu o número de etapas necessárias para a obtenção do diagnóstico correto. Dos três estudos de caso realizados, as etapas necessárias para se chegar ao diagnóstico apropriado diminuiu em uma etapa para o primeiro estudo de caso, diminuiu uma etapa para o segundo estudo de caso, e três etapas a menos para o terceiro estudo de caso. Com estes resultados foi possível demonstrar que a abordagem proposta influiu no processo de diagnóstico aplicado atualmente pelas montadoras e concessionárias analisadas. / The goal of this project is to develop an approach to assist automakers in obtaining information about the problems and failures that occur in the vehicles during their use by drivers, relating the data obtained by reading the telemetry of the vehicle, as well as the perceptions of the driver about a particular failure. The exploration of techniques to optimize automotive diagnosis is a problem to be discussed in Engineering. Diagnostic techniques should support the wide range of systems that will emerge in the coming years. Thus, it is also possible to use the connectivity that mobile phones and vehicles have today, in order to evolve the product offered and improve the customer experience while driving. The customer inclusion in the diagnostic process aims to allow engineers identifies points to be improved in the car, even if they dont present an apparent error. The customer opinion should be considered, since he/she is included in the process as a new "sensor"(the most intelligent and important of all) able to report his/her perceptions. Considering this fact, the motivation of this research is: (i) search for alternatives to efficiently apply vehicle connectivity in the diagnostic process, (ii) enable automakers to obtain more concrete information on the vehicles they sell. The object is provide an interface between the user and the car helping them to perform a more complete preventive diagnoses than only using telemetry. In this project it is sought that there is a greater interaction with the driver, and the experience of the automakers could be included the diagnostic process. Even if the customer isnt so accustomed with the operation of the vehicle, the system must guide the driver by the process. The customer input data is performed by text or voice command. The analysis of this customer input data, a data mining study was performed based on a base that automaker already had. These bases are telephone interviews in which the automaker asks the customer for perceived problems in the car, and then the answers are transcribed to the base. The data mining study was performed to create one classifier which was responsible for receiving the input data from the customer and sorting it into a particular problem related with the multimídia or related to the motor of the vehicle. The software contained in the mobile phone will be responsible asking to the vehicle sensor system for the readings necessary for the customer can to obtain the information he/she wants. An experiment was carried out in which diagnostic analysts answered a questionnaire that sought to analyze whether the proposed system actually influenced the diagnostic process, so the solution of the problems in the vehicle was performed on less steps compared to the current process. The results showed the approach reduced the number of steps required to obtain the correct diagnosis. Of the three case studies performed, the steps required to arrive at appropriate diagnosis decreased in one step to the first case study, one step to the second case study decreased, and three less steps to the third case study . With these results it was possible to demonstrate that the proposed approach influenced the diagnostic process currently applied by the automakers and concessionaires analyzed.

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