Catálogo de publicaciones - libros

The implementation of multi-agents systems aided collaborative and distributed design requires a deeper understanding of the real interactions between actors, inside multidisciplinary teams. In this view, the implementation of these systems requires to observe, to model and to analyze this process with finer granularities levels. This paper presents an approach of collaborative and distributed design process analysis based on the modeling of interactions between actors during this process. The approach consists in discerning, from the real interactions, the relationship between the state-problems and the dynamics of design intermediate objects (DIO) in the computer mediated collaborative and distributed design process. The analysis of state-problems, in a real design process experience shows that the dynamics of the state problems has the influence on dynamics of DIOs.

In this paper, MIDCAD, an integrated design system for Molded Interconnect Devices, is presented and some important techniques for the development of this design system are discussed. A series of MID-related special functions and an integrated MID product model, which are not supported by conventional MCAD und ECAD systems, were developed in MIDCAD. Based on the product model, the simulation of the injection molding process is successfully integrated into MIDCAD. A module supporting the connection of MID-specific automatic placement equipment is also being developed in MIDCAD in order to be able to accomplish a manufacturing-oriented optimization and to guarantee the manufacturability of MID products.

This paper discusses the theoretical aspects and applications of a novel methodology for exploiting a knowledge management editor tool to structure organizational knowledge. An organizational knowledge framework for capturing and representing design and manufacturing know-how has been defined using an ontological approach. The key business benefit of adopting such an approach arises from the closer integration between the key technical and business activities taking place during early design. In particular the effectiveness of decision making is increased.

This contribution is related to the proposition of some fundamental key elements related to knowledge engineering methods applied to digital enterprise performance improvement. To face the new over unstructured information world, engineers have re-thought their ways of collaborating, taking the best of the NTIC. Knowledge structuring has a key role for an efficient actor exchange and innovation creation. A proposition of some extension points from MOKA methodology illustrates these benefits.

Today companies are specialized for partial technology processes. Hundreds, sometimes even thousands, of collaborative processes depend on workers’ interaction and communication in product assembly and disassembly phases. Close coordination accompanies all manufacturing phases of designing a product, whereby the technology documentation is produced in digital form on a CAx workstation. Product Lifecycle Management can be achieved by using specialized software solutions. Some of the Product Lifecycle Management solutions offer an integrated portfolio for engineering design and realization of products and services, which enables companies to create their own digital e-business projects. In this paper are presented modern solutions for collaborative design and examples of using these solutions in the industry.

Today, configuring the mechanical systems and their components correctly so that they meet their functions efficiently and can be easily manufactured and assembled is crucial to effective product design. However, currently there exists no systematic and effective method for designing configurations. This paper proposes and develops a formal representation for supporting the computer-aided design approach for configuration. Two interrelated questions are taken into account: 1. What are configuration features? (Configuration feature concept); 2. How can be constructed the design procedures capable to configure the product? (Computer-aided design approach for configuration). This approach, under the guide of the proposed formal representation, has been implemented in computers by using the functions of current CAD software.

To ensure the robustness of geometric tolerance in collaborative design, a multi-view tolerance data representation is needed as well as a multi-level representation. The goal of multi-level representation is to detail tolerances as knowledge of the product evolves during its development.

After a brief discussion, IPPOP product model and GeoSpelling tolerance model are chosen as basis of definition and implementation of an adaptive tolerance model. In this model, the multi-level and multi-view capabilities are permitted by level and view adaptations. Level and view adaptations consist of an evolution of the viewable tolerance data according to the step of design and to the actors.

These adaptations are presented and applied on a part of an automated cutting machine for fabrics.

Engineering cost estimation is now compulsory from the very first stages of design. The later a cost issue will be detected, the more it will cost. This paper tends to show how to define which information is needed to allow this estimation to be done. A taxonomy that builds a structure in this information has been created. Using this taxonomy, we designed a method to calculate manufacturing costs thanks to an expert system. The cost is determined by considering Cost Entities using pertinent inductors and parametric calculation methods.

Global competition and frequent market changes are challenges facing manufacturing enterprises at present. Manufacturers are faced with new unpredicted modifications at the part design level, which require increased functionality at the system design level. Reconfigurable Manufacturing Systems (RMS) addresses this situation by providing the exact capacity needed when needed. Process planning concepts and methods should be developed to support this new manufacturing environment. Variant process planning systems with their rigid definition of the boundaries of part families do not satisfactorily support Reconfigurable Manufacturing Systems. A semi-generative macro process planning system has been developed and is reported in this paper. Precedence graphs, which depict the precedence relationships between features/operations, are reconfigured by adding and removing nodes. The problem of generating optimal macro-level process plans is combinatorial in nature and proven NP-hard. Hence, a random-based heuristic based on Simulated Annealing is tailored for this problem. Finally, a realistic case study is presented to illustrate the proposed methodology. A family of single-cylinder front covers is used. The proposed method produced good quality optimal solutions and is proven efficient in terms of computation time as demonstrated by the obtained results.

This paper presents a framework to support the analysis of manufacturing processes, providing the correct understanding concerning information and material flows. In addition, this analysis is combined with design structure matrixes based on components to consider better arrangements to the manufacturing process in cells, intending to provide high performance capabilities. To demonstrate the framework an example has been carried out in modeling the manufacturing of a control pack unit, which is a part of an airplane climate control system.