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Med den digitalisering som sker just nu i den industriella världen väcks stor nyfikenhet på hur framtidens tekniker såsom “Augmented Reality” kan appliceras i industriella tillverkningsprocesser. Målet med examensarbetet var att undersöka om och hur AR-teknik kan utnyttjas i industrin för att förbättra nuvarande arbetsprocesser. Två prototyper utvecklades för AR-glasögonen Microsoft HoloLens och utvärderades genom att jämföra tidigare arbetssätt med nya. Testerna av prototyperna visade att effektiviteten, produktionskvalitén och rörligheten ökade för användaren till en bekostnad av sämre ergonomi. / With the digitization that is happening right now in the industrial world, there is a lot of curiosity about how future technologies like Augmented Reality can be applied in industrial manufacturing processes. The aim of the thesis was to investigate whether and how augmented reality technology can be utilized in industries to improve current work processes. Two prototypes were developed for the augmented reality glasses Microsoft HoloLens and evaluated by comparing previous working methods with new ones. Tests of the prototypes showed that efficiency, production quality and mobility increased for the user at the expense of worse ergonomics.

Yes / The process of generating FMEA following document-centric approach is tedious and susceptible to human error. This paper presents preliminary methodology for robotic manufacturing process modelling in MBSE environment with a scope of automating multiple steps of the modelling process using ontology. This is followed by the reasoning towards automatic generation of process FMEA from the MBSE model. The proposed methodology allows to establish robust and self-synchronising links between process-relevant information, reduce the likelihood of human error, and scale down time expenses.

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The aim of this thesis is to design a kilowatt three-phase step-down rotary transformer for a permanent magnet DC motor. The permanent magnet DC motor has an on-rotor drive system, and therefore requiring a power supply that can transfer power to its drive unit without mechanical contact. The rotary transformer has a detached magnetic coupling structure that qualifies it as a potential method for the wireless power transfer. This thesis studies the rotary transformer as a static device, focusing on its core loss. By using a transient finite element analysis of COMSOL Multiphysics and an iron loss prediction model, the rotary transformer was optimized in terms of efficiency and power density for the on-rotor drive system through proper material selection and geometry exploration. After this, a mechanical design, which based on a literature review of the influences of manufacturing processes on electrical steels, was proposed for realizing the core fabrication and the rotary transformer assembly. The results show that the rotary transformer can step down 400 V/50 Hz three-phase voltage to 13.15V in a Delta-wye connection and output 1.17kW power over an air-gap of 0.3mm with 95.94% overall efficiency. The proposed mechanical design enables the transformer to minimize the core loss and the manufacturing cost. Without using resonant inductive coupling, this transformer design simplifies the power supply for the motor, thereby decreasing the motor manufacturing and maintenance cost.

O presente trabalho trata da análise experimental de um sistema de monitoramento baseado na técnica de fusão de sensores, aplicado em uma retificadora cilíndrica externa. A fusão é realizada entre os sinais de potência e emissão acústica para obtenção do parâmetro FAP (Fast Abrasive Power) através do método desenvolvido por Valente (2003). Através da simulação de problemas encontrados nos processos de retificação (falha de sobremetal, colisão, desbalanceamento e vibração), foram captados os sinais de potência e emissão acústica e a partir destes gerado o parâmetro FAP, comparando seu desempenho, na detecção dos problemas, com os outros dois sinais. Para a análise foram construídos os gráficos das variações dos sinais em relação ao tempo de execução do processo e os mapas do FAP e acústico. O sistema de monitoramento avaliado tem como característica baixa complexidade de instalação e execução. Os dados experimentais revelam que o FAP apresenta uma velocidade de resposta maior que a potência e levemente amortecida em relação à emissão acústica. O nível do seu sinal é igual ao da potência mantendo-se homogêneo durante o processo, ao contrário da emissão acústica que pode ser influenciada por diversos outros parâmetros, tais como geometria da peça, distância do sensor, montagem do sensor, entre outros, que independem da interação ferramenta-peça. O resultado é uma resposta dinâmica e confiável, associada à energia do sistema. Estas características são interessantes para o monitoramento de processos de retificação (excluindo a dressagem) sendo superiores àquelas apresentadas isoladamente pelos sinais de potência e emissão acústica. / The present study deals with an experimental analysis of a monitoring system based on a sensor fusion strategy applied to a cylindrical grinding machine. It comprises a fusion of the power and acoustic emission signals and has as main goal to obtain the FAP (Fast Abrasive Power) using the method developed by Valente (2003). Initially, the power and acoustic emission signals were captured under operational dysfunction conditions during the grinding process (stock imperfection, collision, unbalancing e vibration). Then, based on these signals, the FAP parameter was generated and its capability in characterizing operational dysfunctions evaluated against the performance of an individual analysis of the power and acoustic emission signals. For this analysis, FAP and acoustic maps plus plots showing the FAP signals vs. working time were implemented. The experimental data revealed that the FAP presents a faster response than the power signal and a slightly dumped response when compared against the acoustic signal. The signal level of the FAP is similar to the power signal and is homogenous during the machining process. On contrary to the FAP, the acoustic emission signal may be affected by parameters that are not related to the tool-workpiece interactions, workpiece geometry and sensor positioning. The dynamic response of FAP is reliable and linked to the energy of the system. Finally, it should be highlightened that the monitoring system based on the FAP parameter presents low complexity in both implementation and execution. Such characteristics are superior to those observed when using either the power or acoustic emission signals and highly valuable in a system designed to monitor grinding processes.

Geometric quality variables of wafers, such as BOW and WARP, are critical in their applications. A large variation of these quality variables reduces the number of conforming products in the downstream production. Therefore, it is important to reduce the variation by variation modeling, analysis and control for multistage wafer manufacturing processes (MWMPs). First, an intermediate feedforward control strategy is developed to adjust and update the control actions based on the online measurements of intermediate wafer quality measurements. The control performance is evaluated in a MWMP to transform ingots into polished wafers. However, in a complex multistage manufacturing process, the quality variables may have nonlinear relationship with the parameters of the predictors. In this case, piecewise linear regression tree (PLRT) models are used to address nonlinear relationships in MWMP to improve the model prediction performance. The obtained PLRT model is further reconfigured to be complied with the physical layout of the MWMP for feedforward control purposes. The procedure and effectiveness of the proposed method is shown in a case study of a MWMP. Furthermore, as the geometric profiles and quality variables are important quality features for a wafer, fast and accurate measurements of those features are crucial for variation reduction and feedforward control. A sequential measurement strategy is proposed to reduce the number of samples measured in a wafer, yet provide adequate accuracy for the quality feature estimation. A Gaussian process model is used to estimate the true profile of a wafer with improved sensing efficiency. Finally, we study the multistage multimode process monitoring problem. We propose to use PLRTs to inter-relate the variables in a multistage multimode process. A unified charting system is developed. We further study the run length distribution, and optimize the control chart system by considering the modeling uncertainties. Finally, we compare the proposed method with the risk adjustment type of control chart systems based on global regression models, for both simulation study and a wafer manufacturing process.

The aim of this study was to evaluate employee commitment to achieve the primary objective, which was to evaluate employee commitment towards product and process quality. Employees who are engaged in their work and committed to their organisations give companies crucial competitive advantages – including higher productivity, better quality products and lower employee turnover. A thorough literature study was conducted by using the views of different authors and combining them. The concept of quality was defined by making use of the five quality gurus; Deming, Juran, Feigenbaum, Crosby and Ishikawa. The fourteen principles of quality, developed by Deming, were presented in Table 2.1. These principles had the goal of increased productivity, with less rework, less waste of manpower and material resources, resulting in a reduction of costs, to in turn give the organisation greater market share and ultimately better competitive position, by improving the overall quality of an organisation’s work processes. The concept of employee and organisational commitment was defined, and from this study it is evident that employee commitment towards the company is positive and therefore should have a positive effect on their operating environment. The product process flow for this manufacturing concern were discussed to give an overall view of the production processes used in this organisation. An empirical study was completed using a questionnaire survey to determine employee commitment at a manufacturing concern in Gauteng. The questionnaire used for this study was designed to focus on commitment towards internal quality only, to specifically evaluate employee perspective towards product quality, as well as the commitment towards the organisation. Analysis of the responses showed the questionnaire to be reliable and valid. Respondents indicated that they are committed towards the organisation in general across all constructs, but a lack in management trust was a predominant sentiment. The quantitative analysis showed that after a factor analysis was done on the two sections of the questionnaire, four factors for each section were considered as meaningful. These factors were: Affinity, quality awareness, autonomy and corporate image (employee commitment - section B) and employee commitment, task performance, job satisfaction and contextual performance (company relationship – section C). This indicated strong employee commitment towards the organisation. The qualitative results had four areas that all respondents felt needed some attention, and loaded negative towards the organisation. These were HR (trust in management, competency, communication and company culture), skills development, employee development and BBBEE. Thus, drawing conclusions from quantitative results alone could give a company a false sense of employee commitment towards the company and therefore overlook the importance of the roles that employees play in executing strategic plans. Conclusions regarding the findings of the research study were presented and recommendations for this organisation were made. These recommendations are merely a guideline that correlates directly to the empirical analysis made. The research study was evaluated against the primary and secondary objectives with the conclusion that both were achieved. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

The aim of this study was to evaluate employee commitment to achieve the primary objective, which was to evaluate employee commitment towards product and process quality. Employees who are engaged in their work and committed to their organisations give companies crucial competitive advantages – including higher productivity, better quality products and lower employee turnover. A thorough literature study was conducted by using the views of different authors and combining them. The concept of quality was defined by making use of the five quality gurus; Deming, Juran, Feigenbaum, Crosby and Ishikawa. The fourteen principles of quality, developed by Deming, were presented in Table 2.1. These principles had the goal of increased productivity, with less rework, less waste of manpower and material resources, resulting in a reduction of costs, to in turn give the organisation greater market share and ultimately better competitive position, by improving the overall quality of an organisation’s work processes. The concept of employee and organisational commitment was defined, and from this study it is evident that employee commitment towards the company is positive and therefore should have a positive effect on their operating environment. The product process flow for this manufacturing concern were discussed to give an overall view of the production processes used in this organisation. An empirical study was completed using a questionnaire survey to determine employee commitment at a manufacturing concern in Gauteng. The questionnaire used for this study was designed to focus on commitment towards internal quality only, to specifically evaluate employee perspective towards product quality, as well as the commitment towards the organisation. Analysis of the responses showed the questionnaire to be reliable and valid. Respondents indicated that they are committed towards the organisation in general across all constructs, but a lack in management trust was a predominant sentiment. The quantitative analysis showed that after a factor analysis was done on the two sections of the questionnaire, four factors for each section were considered as meaningful. These factors were: Affinity, quality awareness, autonomy and corporate image (employee commitment - section B) and employee commitment, task performance, job satisfaction and contextual performance (company relationship – section C). This indicated strong employee commitment towards the organisation. The qualitative results had four areas that all respondents felt needed some attention, and loaded negative towards the organisation. These were HR (trust in management, competency, communication and company culture), skills development, employee development and BBBEE. Thus, drawing conclusions from quantitative results alone could give a company a false sense of employee commitment towards the company and therefore overlook the importance of the roles that employees play in executing strategic plans. Conclusions regarding the findings of the research study were presented and recommendations for this organisation were made. These recommendations are merely a guideline that correlates directly to the empirical analysis made. The research study was evaluated against the primary and secondary objectives with the conclusion that both were achieved. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013.

La présente étude traite de l’éco-conception d’une pièce structurale, de type poutre tubulaire, en stratifié bio-composite à base de fibres de lin. A cette pièce à concevoir est associé un cas de charge mécanique combinant flexion et torsion et une tenue face aux produits détergents-décontaminant utilisés en environnement médical. Cette étude a pour objectif de montrer la faisabilité d’employer comme architecture de renfort, une mèche de lin pour la réalisation de la pièce. Ce renfort a la particularité d’être constitué de fibres alignées dont la cohésion est assurée par la présence d’un liant par opposition aux fils constituées de fibres retordues. Tout d’abord, pour établir un cahier des charges de fabrication à partir de ceux déjà en vigueur, le comportement mécanique du bio-composite à l’échelle du pli, puis à celui du stratifié et enfin à l’échelle de la poutre stratifié a été modélisé et des critères de conception et de dimensionnement portant sur la rigidité en flexion et en torsion ont été développés de façon analytique. Associée à cette approche et au choix du renfort, le procédé d’enroulement filamentaire a été retenu pour la mise en oeuvre de la pièce. Afin de montrer la compatibilité de la mèche en entrée et le procédé sélectionné, une étude du comportement en traction de la mèche visant à étudier l’effet des paramètres du procédé sur les propriétés mécaniques de la mèche a été réalisée. Cette deuxième phase a été poursuivie par la réalisation de prototypes, suivant le cahier des charges de fabrication établit, qui ont ensuite été analysés en termes de qualité et de performances mécaniques. La corrélation entre ces résultats et ceux obtenus par l’étape de dimensionnement a permis de valider l’approche. Enfin, dans le but d’intégrer l’interaction avec l’environnement opératoire dans le dimensionnement de la pièce, une étude de la durabilité a été réalisée. Celle-ci permet d’établir des stratégies de dimensionnement pour répondre à l’application. / This study aims at eco-designing a structural part, of a hollow beam type, using a laminated flax fibre based bio-composite. The part needs to satisfy a given bending and torsion load case and show compatibility with the cleaning products used in the medical environment. The objective of the study is to investigate the potential of using a flax tow as the reinforcement input for the manufacturing of the beam. The particularity of the reinforcement is that it consists of an assembly of aligned flax fibres held together by a binder as opposed to spun yarns. First, in order to establish the required manufacturing specifications, the mechanical behaviour of the bio-composite at the ply scale, at the laminated and finally at the laminated beam scale was modelled. From this modelling, design and dimensioning criteria based on bending and torsional stiffness were developed analytically. Combining this approach with the choice of the reinforcement, the wet-filament winding process was chosen to manufacture the part. Thus, the tensile behaviour of the flax tow was studied in relation to the process parameters to demonstrate their compatibility. This second phase was followed by the manufacturing of prototypes according the established specifications which were then analysed in terms of quality and mechanical performance. The correlation between experimental results and the model predictions was used to validate the dimensioning approach. Finally and in order to incorporate the interaction of the part with the environment, a durability study was conducted. The latter allows to put forward different dimensioning strategies to meet the required specification.