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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.
91

Možnosti systému Sinumerik 840D při soustružení hřídele pro JAWA 23 / Sinumerik 840D control system for turning of the shaft for JAWA 23

Motl, Martin January 2017 (has links)
This Master’s thesis deals with the proposal manufacturing technology of a shaft with gears on a CNC machine tool. The first part of the thesis is focused on the concise description selected shaft and its use. In the next part of the thesis are state selected materials, which are suitable used for shafts and gears. After that is create drawing component, suggest technological procedure, tool list and machine list which are suitable used for manufacturing selected shaft. In the final part of the thesis is create a CNC program for manufacturing the shaft on the turning and milling machine. Program is created in software SinuTrain 4.7 for control system Sinumerik 840D. The CNC program is verified by graphics simulation to determine a correct function
92

Aplikace softwaru SinuTrain 4.7 v technické přípravě výroby náboje předního kola MTB / Application of SinuTrain 4.7 software in the technical production preparation of the MTB front wheel hub

Valach, Jan January 2017 (has links)
This Master's thesis is focused on technical preparation of the MTB front wheel hub and application of SinuTrain 4.7 computer software. The thesis is divided into four thematic parts. The first part introduces the SinuTrain software and briefly describes the MTB wheel hub. The next section contains the hub design and selection of the suitable material for this component. The third part describes production technologies and selection of the turning machine with suitable tools. The last chapter deals with SinuTrain 4.7 software usage and also presents the results of the production simulations.
93

Developing a Human-Machine-Interface with high usability / Utveckling av ett användbart Människa-Maskin-Gränssnitt

Farneland, Christian, Harrysson, Magnus January 2016 (has links)
When developing a Human-Machine-Interface (HMI) it is important to make sure that it is easy to learn and use, to have high usability. If it does not, the operator of the machine suffers unnecessarily and it also becomes harder to sell for the producer of the machine. The effectiveness and efficiency of the machine drops down when it is hard to operate. To make it easier for future developers to reach a high usability factor when developing a HMI, this thesis aimed to find a carefully prepared process to follow when doing so. The result was a process that was tested out with a HMI prototype for waterjet cutting machines. This prototype was then tested in different use cases by both experienced operators as well as beginners. The testing produced positive feedback on the prototype, proving that the process that had been followed was being successful. / När man utvecklar ett Människa-Maskin-Gränssnitt (HMI) så är det viktigt att se till att det är lätt att lära sig och använda, att det har hög användbarhet. Ifall den inte har det så försämrar det operatörers situation i onödan och gör det svårare för producenter att sälja produkten. Produktionseffektiviteten minskar ifall maskinen är svår att hantera. För att göra det lättare för framtida utvecklare att nå en hög användbarhet när de utvecklar ett HMI så siktade detta examensarbete på att hitta en genomtänkt process att följa vid ett sådant tillfälle. Resultatet blev en process som testades via en HMI prototyp för vattenskärnings maskiner. Denna prototyp blev sedan testad i olika användarfall av både erfarna operatörer och nybörjare. Testerna visade sig ge positiv återkoppling, vilket bevisade att processen som följts upp till den punkten fungerade.
94

Michelangelo speaks : Voice controlled CNC plotter / Michelangelos verk : Röststyrd CNC-ritrobot

Karlsson, Marcus, Maroof, Havan January 2022 (has links)
CNC machines offer numerous advantages over conventional machining. It can be implemented in several ways and one such implementation is a drawing machine. In this bachelor thesis a voice controlled CNC plotter was designed, constructed and programmed. In order to create a better understanding of CNC and voice recognition, research questions were established and studied. The questions were mainly related to drawing speed as well as quality and accuracy of the voice recognition. The hardware of the plotter was mostly built out of 3D-printed parts as well as stepper motors, threaded rods and couplers for the movement system. The software of the plotter consisted of Arduino code, where instructions were written to make, for instance, the appropriate motor move. Tests were executed to gather data that later on were analysed. The analysis showed that the stepper motors and couplers had the greatest impact on the drawing speed as well as showing that the quality decreased when the speed increased. Furthermore the analysis showed that the voice recognition module achieved a high level of accuracy, however only when males spoke as it could not detect female voices. / CNC maskiner har flera fördelar jämfört med konventionella maskiner. De kan implementeras på en mängd olika sätt, exempelvis i en rit robot. I detta kandidatexamensarbete konstruerades och programmerades en röststyr dritrobot. För att erhålla en bättre uppfattning om CNC och röststyrning har två forskningsfrågor undersökts. Frågorna behandlar rithastighet, kvalite samt noggrannhet av röstigenkänningsmodulen. Hårdvaran består för det mesta av 3D-printade komponenter och gängade stänger som utgör rörelse systemet av roboten. Mjukvaran består endast av Arduino kod som innehåller instruktioner för exempelvis vilken motor som ska rotera. Flera experiment utfördes för att erhålla data som därefter analyserades. Analysen visade att stegmotorerna och axelkopplingarna hade störst påverkan på rithastigheten som i sin tur var en stor påverkande faktor för ritkvaliten. Ytterliggare analys visade att röstkortet hade hög noggrannhet men bara när en man talade då det inte kunde tolka kvinnliga röster.
95

Minimering av kassation i CNC processer. / Minimization of scrap in CNC processes

Al Karawi, Osama January 2022 (has links)
Nobel Biocare är ett av de världsledande företagen som tillverkar tandimplantat. Företaget finns på många ställen runt om i världen. Examensarbetet utfördes på N1 avdelningen i Karlskoga.  Företaget har som mål att skapa smarta verkstäder och för att göra det krävs det att svagheter i produktionen identifieras för att sedan hitta lösningar på att de inte uppkommer igen.   Syftet med arbetet är att identifiera rotorsakerna till kassation i CNC processerna och därefter föreslå tre lösningar för att minska/eliminera detta problem. Företaget vill med andra ord veta vilka möjligheter de har idag samt hur de behöver gå till väga i deras strävan att om 2–3 år skapa smarta CNC-verkstäder.   För att undersöka rotorsakerna till kassation gjordes inledningsvis en rad olika analyser med hjälp av Excel där dokumenterat företagsdata användes. Operatörerna intervjuades och egna observationer noterades under besöken på Nobel Biocare.   Det som studien resulterade i var att företaget bör implementera tidtagningsur för varje operatör, byta verktyg efter bestämd tid och ha en genomgång av hur vacuumtrycket regleras. Rotorsakerna är fokuserade på metod och människa och de är att det finns en avsaknad av kvalitétsäkrad rutin för inställning av skärvätska, verktyg byts för sent, ineffektiv metod vid vacuumreglering, känsliga verktyg saknar sensorer och för många enheter produceras innan kontroll. / Nobel Biocare is one of the world's leading companies in the manufacture of dental implants. The company is in many places around the world. The degree project was carried out at the N1 department in Karlskoga.  The company's goal is to create smart workshops and to do so, it is necessary that weaknesses in the production are identified. To find solutions, it is necessary to identity the weaknesses so that they do not arise again.  The purpose of this work is to identify the root causes of scrapping in the CNC processes and then propose three solutions to reduce/eliminate these problems. The company wants to know what opportunities they have and how they need to improve to create smart CNC workshops in 2-3 years.  To investigate the root causes of scrapping, several different analyzes were initially performed using Excel, where documented company data was used. Operators were interviewed and their own observations were noted during the visits to Nobel Biocare.   The study resulted in that the company should implement a timer for each operator, change tools after a certain time and have a review of how the vacuum pressure is regulated. The root cases are focused on method and man, and they are that there is a lack of quality assured routine for setting cutting fluid, tools are changed too late, inefficient method in vacuum control, sensitive tools lack sensors and too many devices are produced before control.
96

Combining additive fabrication and conventional machining technologies to develop a hybrid tooling approach

Booysen, G., Truscott, M., Mosimanyane, D., De Beer, D. January 2009 (has links)
Published Article / South Africa is constantly loosing contracts for the manufacturing of innovative projects to the East, due to its non-competitive mould-making industry. The paper will report on progress made in a specific focus area in mould-making, namely Hybrid Moulds for injection moulding. Hybrid Moulds refers to a hybrid between Additive Fabrication and conventional methods through the use of amongst others, Direct Metal Laser Sintering techniques, combined with conventional CNC machining (High Speed) techniques. Although the emphasis is on an economically viable process for limited production runs, once the moulds have been developed, it normally is pushed to its limits to realize production quantities. One of the competitive edges is the cutting of lead-times, which obviously impacts on production costs. Another aspect is the ability to manufacture short runs of injection moulded parts in the required engineering material Realising that Laser Sintering of metals is an expensive manufacturing process, a concurrent manufacturing process was developed. Intricate mould details, which normally are time-consuming to manufacture through EDM processes, were grown as inserts, while the less-complex parts of the mould is machined in Aluminium through 3 and 5 Axis High Speed CNC Machining. Using a 3-axis CNC wire cutter, pockets will be created where the more complex Laser Sintered Metal inserts will be fitted. One of the competitive edges is the cutting of lead-times, which obviously impacts on production costs. Another aspect is the ability to manufacture short runs of injection moulded parts in the required engineering material.
97

A process planning approach for hybrid manufacture of prismatic polymer components

Zhu, Zicheng January 2013 (has links)
The 21st century demand for innovation is leading towards a revolution in the way products are perceived. This will have a major impact on manufacturing technologies as current product innovation is constrained by the available manufacturing processes, which function independently. One of the most significant developments is the emergence of hybrid manufacturing technologies integrating various individual manufacturing processes. Hybrid processes utilise the advantages of the independent processes whilst minimising their weaknesses as well as extending application areas. Despite the fact that the drawbacks of the individual processes have been significantly reduced, the application of state of the art hybrid technology has always been constrained by the capabilities of their constituent processes either from technical limitations or production costs. In particular, it is virtually impossible to machine complex parts due to limited cutting tool accessibility. By contrast, additive manufacturing (AM) techniques completely solve the tool accessibility issue, but this increased flexibility and automation is achieved by compromising on part accuracy and surface quality. Furthermore, the shape and size of raw materials have to be specific for each hybrid process. More importantly, process planning methods capable of effectively utilising manufacturing resources for hybrid processes are highly limited. In this research, a hybrid process, entitled iAtractive, combining additive, subtractive and inspection processes is proposed. An experimental methodology has been designed and implemented, by which a generative reactionary process planning algorithm (GRP2A) and feature-based decision-making logic (FDL) is developed. GRP2A enables a complex part to be accurately manufactured as one complete unit in the shortest production time possible. FDL provides a number of manufacturing strategies, allowing existing parts to be reused and transformed into final parts with additional features and functionalities. A series of case studies have been manufactured from zero and existing parts, demonstrating the efficacy of the iAtractive process and the developed GRP2A and FDL, which are based on a manual process. The major contribution to knowledge is the new vision for a hybrid process, which is not constrained by the capability of the individual processes and raw material in terms of shape and size. It has been demonstrated that the hybrid process together with GRP2A and FDL provides an effective solution to flexibly and accurately manufacture complex part geometries as well as remanufacture existing parts.
98

CNC milling toolpath generation using genetic algorithms

Essink, Wesley January 2017 (has links)
The prevalence of digital manufacturing in creating increasingly complex products with small batch sizes, requires effective methods for production process planning. Toolpath generation is one of the challenges for manufacturing technologies that function based on the controlled movement of an end effector against a workpiece. The current approaches for determining suitable tool paths are highly dependent on machine structure, manufacturing technology and product geometry. This dependence can be very expensive in a volatile production environment where the products and the resources change quickly. In this research, a novel approach for the flexible generation of toolpaths using a mathematical formulation of the desired objective is proposed. The approach, based on optimisation techniques, is developed by discretising the product space into a number of grid points and determining the optimal sequence of the tool tip visiting these points. To demonstrate the effectiveness of the approach, the context of milling machining has been chosen and a genetic algorithm has been developed to solve the optimisation problem. The results show that with meta-heuristic methods, flexible tool paths can indeed be generated for industrially relevant parts using existing computational power. Future computing platforms, including quantum computers, could extend the applicability of the proposed approach to much more complex domains for instantaneous optimisation of the detailed manufacturing process plan.
99

A novel methodology for modelling CNC machining system resources

Vichare, Parag January 2009 (has links)
No description available.
100

Early cost estimation for additive manufacture

Zhai, Yun 09 1900 (has links)
Additive Manufacture (AM) is a novel manufacturing method; it is a process of forming components by adding materials. Owing to material saving and manufacturing cost saving, more and more research has been focused on metal AM technologies. WAAM is one AM technology, using arc as the heat sources and wire as the material to create parts with weld beads on a layer-by-layer basis. The process can produce components in a wide range of materials, including aluminum, titanium and steel. High deposition rate, material saving and elimination of tooling cost are critical characteristics of the process. Cost estimation is important for all companies. The estimated results can be used as a datum to create a quote for customers or evaluate a quote from suppliers, an important consideration for the application of WAAM is its cost effectiveness compared with traditional manufacture methods. The aim of this research is to find a way to develop a cost estimating method capable of providing manufacturing cost comparison of WAAM with CNC. A cost estimation model for CNC machining has been developed. A process planning approach for WAAM was also defined as part of this research. An Excel calculation spreadsheet was also built and it can be easily used to estimate and compare manufacture cost of WAAM with CNC. Using the method developed in this research, the cost driver analysis of WAAM has been made. The result shows that reduced material cost is the biggest cost driver in WAAM. The cost comparison of WAAM and CNC also has been made and the results show that with the increase of buy-to-fly ratio WAAM is more economical than CNC machining.

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