Internet-enabled fixture design system using case-based reasoning technology

Master'sMASTER OF ENGINEERIN

Design for manufacture using machining features on CNC machining centers

Computer-Aided Design (CAD) and Computer-Aided Manufacturing (CAM) systems have become more and more needed and useful in the machining processes environment. In order to achieve competitive advantage, companies adopted new manufacturing methods. As a consequence, and in machining processes context, the interaction of CAD and CAM has growth over the years in order to increase the production efficiency, as well as to reduce costs and time. The development of this work started with an extensive literature review. In that review, the author found that only a few articles approached the interaction or integration of CAD and CAM systems. Moreover, the authors that studied this interaction focused on systems for turning parts. Thus, there is a gap in the literature related to the integration and automation of these systems when applied to milling parts. Therefore, the purpose of this dissertation is to enable the interaction of these systems in order to provide a completely automated process since the design stage until the machining stage. Finally, the process’ implementation showed that the developed algorithm was able to satisfy the initial requirements of this work, i.e., when given a set of initial parameters, the program drew the required geometry, and then generated the required G-code, such that this code can be sent to the CAM software to machine the workpiece, thereby obtaining the final product.Os sistemas Computer-Aided Design (CAD) and Computer-Aided Manufacturing(CAM) estão, cada vez mais, a ser mais necessários e úteis no contexto da maquinagem. De modo a conseguir vantagem competitiva, as empresas têm adotado novos métodos de produção. Consequentemente, no contexto da indústria da maquinagem, a interação entre CAD e CAM tem crescido nos últimos anos, de modo a permitir uma maior eficácia na produção, assim como também redução de tempo e custo. O desenvolvimento deste trabalho começou com uma extensa revisão da literatura. Nesta revisão, o autor apercebeu-se que apenas alguns artigos se debruçaram sobre a interação ou integração dos sistemas CAD e CAM. Para além disso, os autores desses artigos focaram-se em sistemas para torneamento. Assim, constata-se que existe um espaço livre na literatura no que diz respeito à integração destes sistemas quando aplicados à fresagem. Por isso, o objetivo desta dissertação é permitir a interação dos dois sistemas referidos, de forma a promover um processo completamente automático desde o design até à maquinagem. Por fim, a implementação do processo mostrou que o algoritmo desenvolvido alcançou os objetivos iniciais do trabalho, ou seja, baseando-se apenas nos parâmetros fornecidos, o programa desenhou as geometrias necessárias, sendo depois capaz de gerar o código G respetivo, para que este possa ser transferido para o centro de maquinagem, de modo a que o material possa ser maquinado, dando origem ao produto final

Part grouping for efficient process planning

A framework to provide automated part grouping has been investigated in order to overcome the limitations found in existing part grouping techniques. The work is targeted at: exploration of criteria for feature-based part grouping to make the process planning activity efficient; determination of the optimal number of part families in the part grouping process; development of an experimental hybrid process planning system (HYCAPP); investigation of the effects of improved part grouping on manufacturing cell design. The research work has explored the creation of a feature-based component data model and manufacturing system capability data model, and checked the limitations inherent in existing part grouping techniques i.e. part grouping: around methods; based on part geometry; based on machining processes; and based on machines. [Continues.

Process Comprehension for Interoperable CNC Manufacturing

Over the last 40 years manufacturing industry has enjoyed a rapid growth with the support of various computer-aided systems (CAD, CAPP, CAM etc.) known as CAx. Since the first Numerically Controlled (NC) machine appeared in 1952, there have been many advances in CAx resource capabilities. The information integration and interoperability between different manufacturing resources has become an important and popular research area over the last decade. Computer Numerically Controlled (CNC) machines are an important link in the manufacturing chain and the major contributor to the production capacity of manufacturing industry today. However, most of the research has focused on the information integration of upper systems in the CAD/CAPP /CAM/CNC manufacturing chain, leaving the shop floor as an isolated information island. In particular, there is limited opportunity to capture and feed shopfloor knowledge back to the upper systems. Furthermore, the part programs for the machines are not exchangeable due to the. machine specific postprocessors. Thus there is a further need to consider information interoperability between different CNC machine and other systems. This research investigates the reverse transformation of the CNC part programmes into higher level of process information, entitled process comprehension, to enable the shopfloor interoperability. A novel framework of universal process comprehension is specified and designed. The framework provides a reverse direction of information flow from the CNC machine to upper CAx systems, enabling the interoperability and recycling of the shopfloor knowledge. A prototype implementation of the framework is realised and utilised to demonstrate the functionalities through three industrially inspired test components. The major contribution of this research to knowledge is the new vision of the shopfloor interoperability associated with process knowledge capture and reuse. The research shows that process comprehension of part programmes can provide an effective solution to the issues of the shopfloor interoperability and knowledge reuse in manufacturing industries.EThOS - Electronic Theses Online ServiceGBUnited Kingdo