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<p>Two important deficiencies have been identified for the integration of CAD and automated process planning. These deficiencies stem from the lack of a uniform representation scheme of pans and products, and an effective communication for CAD and process planning. This thesis presents a new approach and original knowledge regarding the integration and individual aspects of feature-based design, cellular manufacturing planning, inspection planning and assembly sequence planning.</p> <p>A high-level new language called Feature-based Design Description Language (FDDL) has been proposed and designed with a feature representation scheme. Its syntax, semantics and vocabulary have been defined with consideration given to the user, the engineering terminology, and the computer implementation. The FDDL system consists of a number of lexical analyzers, a parser and three code generators. Once the products or parts modeled by the FDDL, or by a feature-based modeler, are processed using the FDDL system, inputs are created for manufacturing tasks planning systems.</p> <p>A feature-based modeling and manufacturing tasks planning system has been designed and implemented, and consists of a prototype of a feature-based modeler, the FDDL system, a feature-based cellular manufacturing planning system, a feature-based automated inspection task planner, and a prototype assembly sequence planner. The prototype feature-based modeler is used to model components using features. All expert tolerancing consultant module has been included in the modeler to assist the user. Cellular manufacturing planning deals with group formation and parts assignment to cells. A clustering-based optimization approach has been proposed and implemented for the formation of machine cells and part families. A feature-based assignment system has been developed to integrate the feature-based design and the formed cells. Automata and pattern recognition techniques, in combination with manufacturing knowledge, are used in the system. The feature-based inspection planner has been developed to integrate the feature-based design and a Coordinate Measuring Machine (CMM). Original inspection strategies and knowledge have been developed for CMM, based on the analysis of CMM characteristics, tolerancing theories, features representation, part structure and geometry. A knowledge-based approach has been presented to integrate CAD with the assembly sequence planning. A prototype of such an assembly sequence planner has been developed for generating the assembly sequence for products from the design directly.</p> / Doctor of Philosophy (PhD)

Developing process plans and part programs rapidly and correctly for CNC machine tools plays a vital role in manufacturing. This study is concerned with the development of a web-enabled virtual design and manufacturing application system for rotational parts. The object oriented methodology is used in the application development. Windows Distributed interNet Application (DNA) architecture which describes a framework of building software technologies in an integrated web and client-server model of computing, is employed in the system. The entire system was modeled with Unified Modeling Language (UML), which is an industry-standard visual modeling notation to express software development architectures. Feature-based design approach, being a practical way of linking the design with manufacturing, is implemented in the rotational part design. Users have to be registered in order to use the system. With the supplied web site, users can easily register to system. After registration, the user obtains a password and a unique username. Upon the user authentication, the user session starts. A typical user session involves new or past project selection, material selection, part sketching, blank size definition and cutting parameters determination. After all the steps are completed, process plan and part-program, which are required to manufacture the part on Denford Mirac CNC Turning Machine are generated and displayed on the web site and then saved to the database. The application enables the users to see past projects and to generate new process plan and part programs for different cutting parameters. The process plan, part program and the 2D wire frame drawing of the corresponding part are demonstrated on the web site for the chosen projects.

A previously developed feature library and algorithm are improved in order to develop a software capable of designing of parts to be manufactured using a four-axis CNC lathe. The developed program is composed of sections which are / part geometry design, process planning, cutting tool and machining parameter selection, part program generation and G-code simulation for verification. The developed program is capable of designing parts which contain axisymetric features for turning and related operations, and non-axisymetric features for milling on facial, lateral and cylindrical surfaces. Implemented design procedure defines a blank material shape that can be circular or polygonal cross-sectioned bar or a pre-manufactured part. A detailed database is created for proper cutting tool selection and machining data determination. User can either define or let the program to automatically select the cutting parameters like cutting speed, feed rate and depth of cut for each cutting tool with respect to the workpiece material being machined. After completing design and process planning procedures / information for generation of the CNC program becomes readily available for editing or transferring to the CNC machine tool. User can also simulate the NC program to verify the tool path. User friendly interface, which runs on Autodesk&#039 / s INVENTOR software to visualize the design process, allows design and modifications to be done very easily moreover previously designed parts can be redesigned to produce new modified parts.

Published works cite that 70-80% of the total cost of a product is established during conceptual design, and that improvements in time-to-market, quality, affordability, and global competitiveness require the development of better approaches to assist decision-making during the early stages of product design, as well as facilitate enterprise knowledge management and reuse. For many years, concurrent engineering and teaming have been viewed as “the answer” to product development woes, but studies reveal teaming is not sufficient to handle the task complexities of product development and the long-term goal of enterprise learning. The work of Roberto Verganti provides new insights with regard to reciprocal interdependencies (RIs), feedforward planning, selective anticipation in the context of improving teaming and concurrent engineering, as well as enterprise learning, knowledge management, reuse. In this research, reciprocal interdependencies management (RIM) is offered as a means of addressing product development and concurrent engineering issues occurring in the early stages of design. RIM is combination of Verganti’s concepts, a conceptual RIs structure, new RIM-application strategies, RIM-diagramming, and a conceptual RIM-based decisions support system, which come together to form a vision of a RIM-based enterprise knowledge management system. The conceptual RIM-based DSS is presented using the specific case of supporting a working-level integrated product team (IPT) engaged in the design of an aircraft bulkhead. A qualitative assessment tool is used to compare RIM to other approaches in the literature, and initial results are very favorable.