Thomas Rollmann

A contribution to engineering data sharing in discipline spanning global environments

In any product development process, team collaboration is a key to success. Especially, multidisciplinary and global teamwork is vital in finding a comprehensive solution in product development. But inherent gaps between the participating disciplines and cultures cause disputes and misunderstandings when collaborating. This paper shows the challenges in interdisciplinary and intercultural teamwork, which have to be overcome in order to advance an integrated product development process. The purpose of this research is to improve mutual accommodation in multidisciplinary and international teamwork with the support of modern information technology and technical product documentation.

Three-Dimensional Kernel Development With Parasolid for Integral Sheet Metal Design With Higher Order Bifurcations

The technology of linear flow splitting to produce bifurcated sheet metal structures is researched by the collaborative research center 666 since 2005. So far the product design process is supported by 3D-CAD models on the basis of User-Defined-Features in standard 3D-CAD systems. This paper now presents a new approach for generating 3D-models of integral sheet metal design products with higher order bifurcations based on a low-level 3D-kernel. The emphasis is placed on two aspects, namely the processing of the model’s topology and geometry as well as the software implementation. First, a methodology for the generation and manipulation of the geometry and topology of the Boundary Representation (B-Rep) structure is proposed. This methodology is integrated into an algorithm-based product design approach, which enables engineers to plan and design their complete draft for bifurcated sheet metal parts in an automated, computer aided way. Further functionalities to support the subsequent manufacturing process are developed and integrated. The idea is then implemented by developing a 3D-CAD application using the B-Rep CAD-kernel Parasolid. The programming framework. NET has been chosen for the development of the software on a Windows NT platform using the object-oriented C++ and C# programming languages. The work presented here has significant implications on the quality, accurateness and efficiency of the product generation process of sheet metal products with higher order bifurcations.Copyright

Knowledge Integration in Global Engineering

In the globalised economy, organisational structures and methods used in product development have changed. Companies and organisations have responded by reengineering involved processes, increasing the use of information and communication technologies. Although not new, innovative concepts are required to fully support the resulting distributed virtual product development process. Modern information systems provide the access to information as well as communication, but actual software tools do not integrate the changing circumstances, arising from working in an intercultural field. Global Engineering can create problems of misunderstandings in the product development process leading to a possible lack of information as well as knowledge circulation. Knowledge Integration in collaboration supports successful communication and cooperation. It also supports finding common grounds, processes, and project language. The aim of this paper is to advance knowledge integration in product development to tackle the new challenges in Global Engineering.

Algorithm-Based Product Development: Refined Concepts and Example Applications

Today’s industry faces the competing pressures of having to develop more and more innovative concepts at less cost. One possibility of supporting these rivaling tasks is leaving the idea of traditional product development and introducing an algorithm-based product development paradigm. By this approach it will be possible to quickly generate a large number of possible solutions based on the future product’s primary specifications and requirements. The result of this process is a set of discrete CAD models for each possible solution, from which the designer can select the most suitable one for his specific task. By this approach, engineers shall be able to plan and design their complete draft in an automated, computer aided way. In short, they need to specify the essential requirements and conditions for their design and subsequently will obtain a set of mathematically and functionally optimized CAD-models, from which the best fitting part geometry can be passed on for production.Copyright

PML in Application: An Example of Integral Sheet Metal Design With Higher Order Bifurcations

Processes are very important for the success within many business fields. They define the proper application of methods, technologies, tools, and company structures in order to reach business goals. Not only manufacturing processes have to be defined from the start point to their end, also other processes like product development processes need a proper description to gain success. For example in automotive industries complex product development processes are necessary and defined prior to product development. Over the last decades several product modeling languages have been developed moving to object oriented modeling languages, such as UML, but the used process modeling languages are still procedural. The paradigm shift caused by object oriented description within product modeling languages has to be transferred to process modeling languages. This paper describes an object oriented approach for process modeling, referred to as PML and its application to a complex product development and production process for integrated sheet metal design of higher order bifurcations. Using UML as a starting point an object oriented process modeling method is differentiated. The basic concepts which are needed for process modeling are put into an object oriented context and are explained. The paper gives an outlook, what can be achieved by the new approach.

Feature precedence graphs as an approach for the forming operations planning of integral sheet metal parts

Feature precedence graphs are well-known models to describe products for process planning purposes. In this paper, we propose a process planning approach for integral sheet metal parts with higher order bifurcations. Those products are produced in a continuous manufacturing process by applying the new manufacturing technologies of linear flow splitting and linear bend splitting in combination with roll forming. We introduce new form-features, operation features, and forming features to represent integral sheet metal parts of higher order bifurcations from a design and manufacturing perspective on different levels of detail. The resulting feature precedence graphs are acyclic directed graphs. Thus, topological sorting algorithms can be applied to generate feasible sequences in the model.

Representation, Presentation and Visualization of Uncertainty

Uncertainty in the design process impacts performance parameters of products which are a major problem in the development of highly optimized load bearing systems. Typically, the information flow in the design process is a one way process from the design to subsequent product life cycle phases. Uncertainty about product properties leads to less economic and less safe products. In this paper an innovative approach to enable modeling and communication of uncertain properties along the product life cycle and the sophisticated presentation and visualization of these uncertainties is proposed. This approach is based on a three layer concept including a representation layer, a presentation layer and a visualization layer. The approach enables the visualization of a broad spectrum of process and product properties with respect to different specifications of each property e.g. single values, intervals, fuzziness and stochastic measures which may occur along the product life cycle.

Neutraler Datenaustausch in der Digitalen Fabrik

Kurzfassung Die Werkzeuge der Digitalen Fabrik haben auf Grund immer kürzer werdenden Produktlebenszyklen und des hohen Anspruchs an Qualität, Kosten und Zeit einen hohen Stellenwert. Diese Werkzeuge leisten bei der Planung und Optimierung der Produktion einen wichtigen Beitrag, zum Beispiel Produktionskapazitäten oder Losgrößen zu determinieren und somit die Planungsqualität und -sicherheit zu erhöhen. Für eine ganzheitliche Betrachtung von Fertigungssystemen müssen die Werkzeuge der Digitalen Fabrik in eine heterogene Systemlandschaft eingebettet werden, wodurch Informationen aus den verschiedensten Bereichen des betrieblichen Wertschöpfungssystems einfließen. Aufbauend auf diesen Erkenntnissen wird ein Ansatz zum Austausch von fabrikspezifizierenden Daten und Daten zur Beschreibung von Fabrikstrukturen auf neutraler Datenbasis vorgestellt.

A New Event Model for PML

Processes are very important for the success within many business fields. They define the proper application of methods, technologies and company structures in order to reach business goals. Not only manufacturing processes have to be defined from the start point to their end, also other processes like product development processes need a proper description to gain success. For example in automotive industries complex product development processes are necessary and defined prior to product development. This paper is an advancement of PML - the object-oriented Process Modeling Language, introduced in earlier publications. A new Event Model for PML is introduced and the association to the resources model and the product data model is described. The concepts are shown by some examples to illustrate their usage.