Siegmar Haasis

Recent and future trends in cost estimation

Increasingly keen competition and the demand for shorter times to market are driving innovative approaches within the product creation process. When considering the factors that decide the success of a product in the market today, it becomes clear that cost is as crucial as quality and functionality. This paper gives an overview of the state of the art and future trends in the field of cost estimation. First, a short overview of the relevant terms from the field of cost accounting is given. The impact of product development on costs is elaborated and the requirements for a cost calculation model are outlined. The currently prevailing methodological approaches for cost estimation in the product development process are set out and classified in the scientific context with a schema being introduced to reduce the vast number of methods to a single basic structure. Finally, various methods for cost estimation are set out and their shortcomings summarized. This paper aims at building a foundation for future research in the field of cost estimation and ends with a look at future work.

CAx/engineering data management integration: Enabler for methodical benefits in the design process

Although functionalities of engineering systems are rocketing, they currently cannot cope with the development of new engineering methods. Additionally, the data management systems and concepts of today fail to adequately support these innovative functionalities. The integration of new methods into existing and new system environments are often not taken into account. In addition to the optimization of individual tool functionalities, integrated system architectures are needed. This paper will take a look at today’s and tomorrow’s engineering practices, showing that major benefits can only be achieved if based on a thorough concept of engineering system integration. Different integration concepts are elaborated, with some of them being already applied in a prototypical implementation in existing processes. First results are presented and discussed. Best Young Design Researcher paper at the Design 2004 Society Conference in Dubrovnik, as judged by a panel in which Professors Marjanović, Birkhofer and Andreasen were included.

ASSEMBLY-ORIENTED DESIGN IN AUTOMOTIVE ENGINEERING

The current engineering process in the automotive industry is chiefly part oriented. What counts most, however, is the optimisation of complete assemblies. Assembly-oriented design (AOD) is introduced as an approach which optimises the development process in a way that benefits both development itself and downstream processes. It breaks with the paradigm of part-orientation prevailing today and promotes a top-down approach towards the creation of complex assemblies; it combines different aspects of methodology and engineering system design. Whereas design for assembly (DFA) subordinates development to the optimisation of the production process, AOD promotes an integrative approach which offers potentials along the complete process chain.

ULEO - Universal Linking of Engineering Objects

This paper reports on ongoing research in the field of feature-based product development. The resulting ULEO approach aims at enabling a high-quality flow of information between applications and at universal automation of product model generation. This is achieved by modeling all classes of relevant objects within a Unified Model of Engineering Objects (UMEO). All types of relationships are modeled inside a dedicated meta taxonomy of relation types and materialize inside the UMEO. Informational relations represent ontological knowledge about dependencies between object classes and are suited for cross-linking of product models. Generative relations describe knowledge on how to create instances automatically.

Challenges for CAx and EDM in an international automotive company

In design and manufacturing of passenger cars, changes in processes and tools pose new challenges for the management of engineering data. In this paper, the status quo, challenges, and developments are elaborated using the example of a globally operating automobile manufacturer. Special attention is given to the complexity and variance of the products, to paradigm shifts in design philosophies, to trends targeting the IT environment, and to user bias. Finally, conclusions are drawn for future CAx and EDM concepts and strategies.

CAx/EDM integration : enabler for methodical benefits in the design process

Although functionalities of engineering systems are rocketing, they currently cannot cope with the development of new engineering methods. Additionally, the data management systems and concepts of today fail to adequately support these innovative functionalities. The integration of new methods into existing and new system environments are often not taken into account. In addition to the optimisation of individual tool functionalities, integrated system architectures are needed. This paper will take a look at today’s and tomorrow’s engineering practices, showing that major benefits can only be achieved if based on a thorough concept of engineering system integration.

Feature-Based Integration of Product, Process and Resources

The processes currently deployed within the organization of today are being greatly impacted by the demand for drastic reductions in lead-times accompanied by cuts in development and manufacturing costs. Furthermore, the trend towards geographic separation of development and manufacturing facilities and the growing requirement that external partners be seamlessly integrated into internal processes, together with increasing globalisation in manufacturing which necessitates that product design take — often very different — manufacturing conditions into consideration, make the efficient design of both internal and cross-organizational process chains, i.e. comprehensive, complete digital product and production planning, a necessity. The use of features as carriers of descriptive and semantic information within the product development process has led to a substantial decrease in redundant data input and, thus, to a significant reduction in effort and the probability of errors occurring while, at the same time, supporting a product design which is aligned with the manufacturing processes deployed. Supplemented by process data and methods geared for the specification of production aspects and workflows, feature-based process models enhance the transparency of manufacturing capability and resource modelling, thus serving as the foundation for the introduction of new organizational concepts such as simultaneous or concurrent engineering. This work describes the role features play in an organization’s overall process chain: the connection between design, manufacturing and measuring features and their consolidation to a backbone for the continuous flow of information for the complete modelling of the product, the process and the resources.

APPLYING UNIVERSAL LINKING OF ENGINEERING OBJECTS IN THE AUTOMOTIVE INDUSTRY - PRACTICAL ASPECTS, BENEFITS, AND PROTOTYPES

The bi-directional communication of CAD programs with subsequent applications such as process planning remains a key challenge in design-for-the-lifecycle. While it seems sensible that individual applications use their own collection of feature types and thereby allow users to have their specific perspective of the product, it is still difficult to automatically close the gap between the variety of applications. Universal Linking of Engineering Objects (ULEO) targets this concern. It is general enough to facilitate informational integration of the applications along the process chain. This paper examines a number of scenarios for exploiting ULEO’s benefits in the field of automotive development and reports on the associated prototypical software implementations. Principle alternatives and technical aspects relevant for applying ULEO are discussed in some detail beforehand.Copyright

The Feature-Based Styling Process in Car Body Engineering

The quality standards defined today and the high demands placed on the appearance of a vehicle, i.e. its styling, have combined to increase the degree of difficulty and the complexity of the automotive development process. In addition frequent data exchange within this process between styling, body-in-white design, and manufacturing is necessary since styling changes, for example, impact the exterior surfaces which may necessitate reinforcement modifications. After each modification the inner parts and styling must be brought in line. Today, topological structural changes in most cases involve still another completely new generation of the parametric model and the actualization of the parametrically developed body-in-white construction due to the fact that changes of class-A surfaces are supported by only a few CAx systems. This paper presents a methodology for parametric- and associative-driven design for class-A surfaces (exterior) to support all the engineering functions for the translation of the styling model into the inner parts (body in white) and into manufacturing. Also, it analyzes the working methods of the stylist in order to define the set of features meaningful for aesthetic design.

The Welding Process Based on Intelligent Features in Car Body Development and Production

Today’s automotive market is highly competitive. As a result carmakers are being forced to offer newer, better, and cheaper cars in a shorter period of time in order to stay competitive in the global market. One way to achieve this goal is the introduction of platforms where each part is produced in a highly integrated and cost-efficient process. Now, during the design phase, the demands of cost-effective manufacturing must be taken into account. During the design phase, parts — in addition to the optimization of their function — have to be optimized with respect to their manufacturing process. Design, engineering, and production planning of a part are integrated to a high degree and often take place at the same time (concurrent engineering). Starting with the analysis of the joining process, this paper discusses requirements for an automated welding process based on feature technology. In this sense, flange creation and design, manufacturing, and welding requirements for automatic generation of spot weld are described. A process-oriented prototype is described, which has been integrated in CATIA V5, currently used as CAD-CAM system, and which fit the requirements of the designers and process planners.Copyright