Automatic feature extraction from conventional CAD model to support feature-based design approach for the sheet metal stamping industries

Despite the continuing improvement in computer aided design (CAD) systems and improvements in computer aided manufacturing (CAM), the process planning activity has still not been completely integrated into the CAD/CAM cycle. Particularly in sheet metal stamping industries human interpretation of CAD data is required to extract the geometry and technological information of a component. As a result most CAD systems are used as advanced drafting and drawing management tools by designers. Thus the responsibility for interpreting the design data required for extracting the manufacturing part features still resides with the process planner. Which has increase possibilities of entering errors with design data. A need, therefore, exists to develop expert system for automatic features extraction from a CAD database. An application software was developed for automatic feature extraction from conventional CAD model database to impliment feature-based design approach for the sheet metal stamping industries

Query processing of geometric objects with free form boundarie sin spatial databases

The increasing demand for the use of database systems as an integrating factor in CAD/CAM applications has necessitated the development of database systems with appropriate modelling and retrieval capabilities. One essential problem is the treatment of geometric data which has led to the development of spatial databases. Unfortunately, most proposals only deal with simple geometric objects like multidimensional points and rectangles. On the other hand, there has been a rapid development in the field of representing geometric objects with free form curves or surfaces, initiated by engineering applications such as mechanical engineering, aviation or astronautics. Therefore, we propose a concept for the realization of spatial retrieval operations on geometric objects with free form boundaries, such as B-spline or Bezier curves, which can easily be integrated in a database management system. The key concept is the encapsulation of geometric operations in a so-called query processor. First, this enables the definition of an interface allowing the integration into the data model and the definition of the query language of a database system for complex objects. Second, the approach allows the use of an arbitrary representation of the geometric objects. After a short description of the query processor, we propose some representations for free form objects determined by B-spline or Bezier curves. The goal of efficient query processing in a database environment is achieved using a combination of decomposition techniques and spatial access methods. Finally, we present some experimental results indicating that the performance of decomposition techniques is clearly superior to traditional query processing strategies for geometric objects with free form boundaries

Kernel arquitecture for CAD/CAM in shipbuilding enviroments

The capabilities of complex software products such as CAD/CAM systems are strongly supported by basic information technologies related with data management, visualization, communication, geometry modeling and others related with the development process. These basic information technologies are involved in a continuous evolution process, but over recent years this evolution has been dramatic. The main reason for this has been that new hardware capabilities (including graphic cards) are available at very low cost, but also a contributing factor has been the evolution of the prices of basic software. To take advantage of these new features, the existing CAD/CAM systems must undergo a complete and drastic redesign. This process is complicated but strategic for the future evolution of a system. There are several examples in the market of how a bad decision has lead to a cul-de-sac (both technically and commercially). This paper describes what the authors consider are the basic architectural components of a kernel for a CAD/CAM system oriented to shipbuilding. The proposed solution is a combination of in-house developed frameworks together with commercial products that are accepted as standard components. The proportion of in-house frameworks within this combination of products is a key factor, especially when considering CAD/CAM systems oriented to shipbuilding. General-purpose CAD/CAM systems are mainly oriented to the mechanical CAD market. For this reason several basic products exist devoted to geometry modelling in this context. But these basic products are not well suited to deal with the very specific geometry modelling requirements of a CAD/CAM system oriented to shipbuilding. The complexity of the ship model, the different model requirements through its short and changing life cycle and the many different disciplines involved in the process are reasons for this inadequacy. Apart from these basic frameworks, specific shipbuilding frameworks are also required. This second layer is built over the basic technology components mentioned above. This paper describes in detail the technological frameworks which have been used to develop the latest FORAN version.Postprint (published version

TOPAZ:a tool kit for the assembly of transaction managers for non-standard applications

'Advanced database applications', such as CAD/CAM, CASE, large AI applications or image and voice processing, place demands on transaction management which differ substantially from those in traditional database applications. In particular, there is a need to support 'enriched' data models (which include, for example, complex objects or version and configuration management), 'synergistic' cooperative work, and application- or user-supported consistency. Unfortunately, the demands are not only sophisticated but also diversified, which means that different application areas might even place contradictory demands on transaction management. This paper deals with these problems and offers a solution by introducing a flexible and adaptable tool kit approach for transaction management

A framework for green manufacturing practicies in small and medium enterprises in Malaysia

Green Manufacturing Practices (GrMP) is a term used to describe manufacturing practices that do not harm the environment during any part of the manufacturing process. It emphasizes the use of processes that do not pollute the environment or harm consumers, employees, or other members of the community. Small and medium enterprises (SMEs) are moving toward sustainable alternatives through GrMP method. It stresses on critical factors such as organisational style, eco-knowledge, business environment, society influences, supply chain management and technology network. Large size industries are more compelled to do so compared to SMEs due to the fact that they are more influential with better organizational management and good financial stability compared to SMEs. However, SMEs are trying to adapt GrMP as a mandatory process, but lack of proper framework which guide them for implementation. Therefore, this study developes the framework of GrMP for local SMEs. The study involves enablers and barriers in implementing GrMP from previous literatures. This work formulate a framework based on relationship between criticals factors with enablers and barriers. 59 of respondents from local industries in Malaysia were selected as respondents based on six of critical factors divided into two parts which are enablers and barriers. The questionnaire are designed based on this. Survey were evaluated by using Statistical Package for the Social Sciences (SPSS) version 23, in terms of correlation, reliability, central tendency and variability testing. The finding on this study in the term of framework will help SMEs to implementing GrMP. Framework formulate relates the critical factors from previous literature and enablers and barriers from survey based on perception of industries expert. GrMP for SMEs are the first step of environmental awareness and ecological responsibilties

DFM synthesis approach based on product-process interface modelling. Application to the peen forming process.

Engineering design approach are curently CAD-centred design process. Manufacturing information is selected and assessed very late in the design process and above all as a reactive task instead of being proactive to lead the design choices. DFM appraoches are therefore assesment methods that compare several design alternatives and not real design approaches at all. Main added value of this research work concerns the use of a product-process interface model to jointly manage both the product and the manufacturing data in a proactive DFM way. The DFM synthesis approach and the interface model are presented via the description of the DFM software platform

The Effect of Using Computer Technology Tools to Enhance the Teaching-Learning Process in CAD-CAM-CNC Module in Mechanical Engineering Subject Area

This study presents the evaluation of Computer Assisted Learning (CAL) package included in the teaching and learning methodology of computer aided design- computer aided design - computer numerical control (CAD-CAM-CNC) module. Three groups of students with similar pre-abilities were exposed to three different teaching learning methodologies.The effectiveness of these three methods was determined by questionnaires completed by the students and collected by first author. Their answers were analysed quantitatively and qualitatively. The various categories used in the questionnaire was student’s attitudes towards learning CAD-CAM-CNC subjects, students’ opinions about their lecturers approaches to teaching process, students’ opinions and views about various aspects the CAD-CAM-CNC. The study concludes that the students taught with a combination of CAL package and traditional methods were more effective, efficient and satisfied with their learning experiences. So the proposed hybrid learning method (CAI plus traditional teaching method) is most suited for CAD-CAM-CNC teaching. Computer Technology; Computer-Assisted Instruction (CAI); Computer Assisted Learning (CAL); Computer Aided Design (CAD); Computer Aided Manufacturing (CAM); Computer Numerical Control (CNC)

設計・製造コラボレイトシステムのWebインターフェイスの構築--開発環境の整備とデータベースによるユーザ管理 (情報学部開設記念) -- (情報学部開設記念論文)

　In order to support small product companies in Yamaguchi prefecture which are using CAD/CAM, we (Yamaguchi Prefectural Industrial Technology Institute) have begun to develop a collaboration system of design and manufacturing through network.　This paper describes about a part of the development, i.e. the construction of web-interface using operation system Linux, web application server Zope, database engine PostgreSQL, mail server Qmail, and especially about preparing the environment of software development, and constructing the user-management system using web application server (Zope) and database (PostgreSQL)

EU-China collaboration in design: research in Web-enabled collaborative design supported by the Asia-Link and Asia IT&C projects

The research of Web-enabled collaboration in total design supported by the European Union's Asia Link project [1] and Asia IT&C project is reported in this paper. The two projects both aim at enhancing research collaboration between the EU and China. The Virtual Research Institute (VRI) is described first, which is the platform for the collaboration for the Asia Link project and is established by utilizing the advanced Web techniques; and then, the framework for the collaboration and the Web techniques involved in the research are presented which represent the major research of the Asia IT&C project. The effective collaboration between the project partners and the impacts of the project outcome on the partnership are also discussed