The design and implementation of material and information flow for manufacturing systems

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2000.Includes bibliographical references (p. 143-145).Production systems are characterized by complex interactions between elements, both human and mechanical, with the goal to accomplish certain high-level manufacturing objectives. In order to ensure that the decisions made and the actions taken during the design and implementation of production systems are aligned with all of the objectives, a structured approach must be followed. In developing this structured approach, the axiomatic design methodology is applied, which provides the means for creating a hierarchy of system design objectives (what to do) and solutions (how to do it). From this conceptual design process, a Production System Design and Implementation (PSDI) Path is presented here. The PSDI Path guides the design through a series of steps in creating a successful physical manufacturing system environment in terms of the original high-level objectives. Defining the material and information flow in the system is a critical part of the PSDI path. Based on the steps in the PSDI Path and the design hierarchy, a procedure for constructing the material and information flow in the production system is developed. To aid in the design of material and information flow in the manufacturing system, a manufacturing system modeling environment is developed as the tool for visualizing and communicating the flow in the manufacturing system design. KEYWORDS: Lean Manufacturing, Value Stream Management, Manufacturing System Design, Production System Design, Cellular Manufacturing, Axiomatic Design.by Brandon J. Carrus.S.M

Automatic Feature Recognition and Tool Path Generation Integrated with Process Planning

The simulation and implementation of Automatic recognition of features from Boundary representation solid models and tool path generation for precision machining of features with free form surfaces is presented in this thesis. A new approach for extracting machining features from a CAD model is developed for a wide range of application domains. Feature-based representation is a technology for integrating geometric modeling and engineering analysis for the life cycle. The concept of feature incorporates the association of a specific engineering meaning to a part of the model. The overall goal of feature-based representations is to convert low level geometrical information into high level description in terms of form, functional, manufacturing or assembly features. Using the boundary representation technique, the information required for manufacturing process can be directly extracted from the CAD model. It also consists of a parameterization strategy to extract user-defined parameters from the recognized features. The extracted parameters from the individual features are used to generate the tool path for machining operations regardless of the intersection of one or more features. The tool path generation is carried out in two phases such as roughing and finishing. Various types of tool paths such as one-way, zig-zag, contour parallel are generated according to the type of the feature for the roughing operation. The algorithm automatically plans the sequence of machining operation with respect to the feature location, and also selects the type of tool and tool path to be used according to the feature. The finishing operation uses the tool path generation strategy in the same manner as used in roughing operation. The algorithm is implemented using the Solid works API library and verified with CNC milling simulator. The results of the work proved the efficiency of this approach and it demonstrate the applicability

Work-Life Balance, Job Satisfaction, and Career Development of Millennials: The Mediating Role of Affective Commitment

Since millennials dominate today’s workforce, it is necessary to explore the career development of this generation. Therefore, this study aims to examine the career development of the millennial generation based on work-life balance and satisfaction factors mediated by affective commitment. This study involved 160 respondents, most of whom were female manufacturing workers. This study took a quantitative approach and used structural equation modeling to examine predictors of career development among millennials. We found that work-life balance and job satisfaction positively affect affective commitment and affective commitment positively affects career development. However, the results revealed no direct relationship between work-life balance and career development. The effect of work-life balance on career development is only significant if it is mediated by job satisfaction. A clear and targeted career path is very important for the continuity of millennial career development. This study suggests technology-based ways to engage millennials using digital tools to interact and share information, resulting in better work-life balance and higher productivity. This study implies that work-life balance is necessary for enhancing job satisfaction, emotional commitment, and career advancement

From 3D Models to 3D Prints: an Overview of the Processing Pipeline

Due to the wide diffusion of 3D printing technologies, geometric algorithms for Additive Manufacturing are being invented at an impressive speed. Each single step, in particular along the Process Planning pipeline, can now count on dozens of methods that prepare the 3D model for fabrication, while analysing and optimizing geometry and machine instructions for various objectives. This report provides a classification of this huge state of the art, and elicits the relation between each single algorithm and a list of desirable objectives during Process Planning. The objectives themselves are listed and discussed, along with possible needs for tradeoffs. Additive Manufacturing technologies are broadly categorized to explicitly relate classes of devices and supported features. Finally, this report offers an analysis of the state of the art while discussing open and challenging problems from both an academic and an industrial perspective.Comment: European Union (EU); Horizon 2020; H2020-FoF-2015; RIA - Research and Innovation action; Grant agreement N. 68044

A digital definition method for manufacturing model of aircraft integral panel

The manufacturing model of aircraft integral panel is presented based on the analysis of its structure and manufacturing process. The manufacturing model for each key process consists of model for processing and model for workpiece to bridge digital design and fabricating. Model for workpiece is used to express the target part information at the end of some operation. Model for processing is used to describe the intermediate state information, and it aims to attain but is different the workpiece because of process factors. The definition flow of the manufacturing model is given. The modeling approach of integral panel part blank from shot peen forming part model orienting to NC cutting is proposed and exemplified. It is analyzed that the approaches above can define the models accurately and totally to meet the needs of process planning , NC fabricating and inspecting

Development of the evaluation system for automobile remanufacturing

By 2015, the EU directives required the automobile manufacturers to produce a vehicle that contains reusable and / or recoverable parts at least 95% of total weight. In the developed countries, the legislative issue the take – back policy which requires the manufacturers to consider the end – of – life (EOL) of their products at early design stage. The goal of this paper is to propose a framework of development methodology that focuses on integrated design for remanufacturing evaluation system. This system supports the automobile product design and development at the early design phase. The proposed method is divided into two phases. The first phase aims to identify the suitable EOL process. The second phase aims to verify the most economical EOL process. The proposed method incorporates the Case base Reasoning [CBR] into the remanufacturing techniques. It is expected that the proposed method can provide the EOL with decision support during designing the automobile parts at the early design stage