Now showing 1 - 10 of 125
  • Publication
    An optimal algorithm for the robotic assembly system design problem: An industrial case study
    ( 2020)
    Hagemann, S.
    ;
    Stark, R.
    The design process of flow-oriented assembly systems is characterized by being both highly complex and time consuming. Especially those design processes categorized into robotic and multi variant encountered in the automotive body-in-white production stages. Unlike established manual and template-based assembly system design models, which are currently applied in industry, the here presented novel approach uses a knowledge-based search algorithm and automatically generates optimal assembly system configurations. The algorithm has been implemented in a software prototype and the results have been validated against different large-size industrial scenarios in the automotive field of body-in-white production.
  • Publication
    Stufenmodell zur Strukturierung digitaler Assistenzfunktionen: Digital assistierte Montageplanung
    ( 2020)
    Bußwinkel, L.
    ;
    Hauk, J.-C.
    ;
    Schneider, H.
    ;
    Stark, R.
    Die Montageplanung ist durch große manuelle Aufwände sowie eine auf Erfahrungen und Expertenwissen basierende Entscheidungsfindung geprägt. Trotz zahlreicher Forschungsaktivitäten wird nur eine geringe Automatisierung der Montageplanung erreicht. Daher wird für die Montageplanung ein Assistenzstufenmodell erarbeitet, das zukünftig eine systematische Entwicklung digitaler Assistenzsysteme erlaubt, die in der industriellen Praxis einen Mehrwert erzeugen.
  • Publication
    An Ensemble Learning based Hierarchical Multi-label Classification Approach to Identify Impacts of Engineering Changes
    ( 2020)
    Pan, Y.
    ;
    Stark, R.
    In the process of complex products development, design decisions of products are constantly changed to improve quality or functionality, reduce costs, respond to statutory constraints or implement wishes from customers, with respect to new functionality. The changes on already released design decisions are known as Engineering Changes (EC). Due to interdependency, changes on one component may cause changes on another, and this will spread along the product structure. Therefore, to completely identify the affected components of engineering changes is a major challenge. This paper presents a novel approach to use properties of components as target variables and applying the predicted properties to locate the EC affected components in product structure. We create a hierarchy of the properties and divide the label space into separate communities. A stacked multi-label classifier is trained in each community, the result is obtained by union of assigned labels from different communities. Finally, the predicted labels are adjusted by incorporating the hierarchical relation. Experiments conducted on real-world industrial EC dataset with mixed data types. Results demonstrated that, the ensemble framework in our approach is more efficient and effective than our baseline models and has achieved superior performance on real industrial engineering change data.
  • Publication
    Integration of automated structure mechanic analyses into production process simulation
    ( 2019)
    Schmitz, M.B.
    ;
    Stark, R.
    To produce individual variants of a given product, each variant has to be assessed with respect to their mechanical integrity. This is usually done in the course of product design by assessing all required variants. However, during the lifetime of a product several changes of the existing variants occur or new variants will be created. In this paper a method is described how to integrate and automate the assessment of the mechanical integrity of the product variants directly into the production process by exploiting modern computer methods and automated set-up of state-of-the-art CAE methods. We show this on a demonstrator of a smart factory, that produces disks which can be customized to a large extend. The disks undergo a milling process, which alters the structural properties of the disks. Generally, it cannot be guaranteed upfront that a variant that can be produced is also strong enough to withstand the loads in the application. Therefore, the integrated FEM analyses are computing and assessing the load cases deduced from the use cases of the disks and the loads that occur during milling and handling in the factory. The assessment of the results is done automatically and if positive the production process is started.
  • Publication
    Configuration Equilibrium Model of Product Variant Design Driven by Customer Requirements
    ( 2019)
    Yang, Q.
    ;
    Bian, X.
    ;
    Stark, R.
    ;
    Fresemann, C.
    ;
    Song, F.
    In view of the dynamic change of customer requirements (CRs) during the process of product use, in this paper we propose a Bayesian Nash equilibrium configuration model for product variant design driven by CRs. By analyzing CRs, the complete variant requirements of the products can be obtained. Combined with modularization and parameterization variant design methods, a parametric variant instance is proposed. Since cost and delivery time are affected by the product variant design, firms and customers are established as two decision-making bodies, and Bayesian Nash theory is introduced to the product configuration. The theory takes the product cost and customer satisfaction as the payoff function of the game, and based on the threshold value search of the customer satisfaction it determines the strategy set of the two parties. The Nash equilibrium solution equation is established and solved by a simulated annealing algorithm. The optimal product configuration scheme satisfying the interests of both sides of the game is obtained. Finally, the automatic guided vehicle (AGV) is taken as an example to illustrate the effectiveness and practicability of the method.
  • Publication
    Reifegradmodelle in der Produktentwicklung
    ( 2019)
    Randermann, M.
    ;
    Blüher, T.
    ;
    Jochem, R.
    ;
    Stark, R.
    In product development, maturity turity models are a suitable instrument for evaluating and improving the engineering environment. The following literature analysis examines differences and similarities between existing maturity models for product development and analyses them regarding their process areas in which respective quality characteristics for efficient product development projects are located.
  • Publication
    Semantic Assistance System for Providing Smart Services and Reasoning in Aero-Engine Manufacturing
    ( 2019)
    Gogineni, S.
    ;
    Exner, K.
    ;
    Stark, R.
    ;
    Nickel, J.
    ;
    Oeler, M.
    ;
    Witte, H.
    Digitalization has led to creation and management of knowledge using information and communication technology tools (ICT) and systems. Implementing such tools and systems across the lifecycle is a tedious process and not to forget customizing them to the company's processes is an additional challenge. Hence, data in a company is spread across multiple ICT in heterogeneous data formats and are sparsely connected together. Connecting the various data sources to enable a single point of access of information in a company can improve performance, quality, reduce costs and time to market. The usage of semantic technologies enables meaningful and structured unification of these distributed data sources and therefore, is providing advantages such as reusability, interoperability, and information flow across the entire value chain. Extending these capabilities with smart services and intelligent algorithms, is advantageous for the user. The user will then receive context sensitive information and additional suggestions that increases the speed, quality and efficiency of work. This paper aims at describing the design, developing and validation of an assistance system for semantic product data, in cooperation with Rolls-Royce Deutschland, an aerospace manufacturing industry, using semantic technologies and machine learning.
  • Publication
    Application of industrial methods in engineering education
    ( 2019)
    Kind, S.
    ;
    Dybov, A.
    ;
    Buchholz, C.
    ;
    Stark, R.
    Modern trends and challenges like an increased level of product complexity and reduced time for development require new, improved skills for future employees. Potential industrial methods based on early project planning, interdisciplinary product solutions and a systematic preparation for production are researched and presented within this paper. Future employees need to understand the processes and methods of product implementation and production. Especially the last stages of product development require additional attention, since these are the most challenging phases regarding integration and implementation starting from initial prototyping up to a functional product. Industrial feedback proves, that these skills are not taught in an appropriate extend by todays academic education, concluding that todays' graduates are not well prepared for tomorrow's job challenges. Following the gaps in today's education a student project lecture was developed, that teaches and applies industry-related development methods addressing advanced master students. Focus of the related student project includes a constant review of project management practices in industrial design reviews, as well as the gathering and definition of requirements. In addition to this, development methods for functional prototypes are taught and applied. Especially the actual creation of prototypes is addressing the product integration and testing phase. To present the above-mentioned methods and an innovative testing environment, two successfully applied use cases are described within this paper. These are covering the entire development process starting from early requirements gathering, accompanied by model-based system engineering.
  • Publication
    Approaching Knowledge Dynamics Across the Product Development Process with Methods of Social Research
    ( 2019)
    Wang, W.M.
    ;
    Mörike, F.
    ;
    Hergesell, J.
    ;
    Baur, N.
    ;
    Feufel, M.
    ;
    Stark, R.
    Knowledge is a crucial factor in state-of-the-art product development. It is often provided by stakeholders from divers disciplinary and individual backgrounds and has to be integrated to create competitive products. Still, it is not fully understood, how knowledge is generated, transformed, transferred and integrated in complex product development processes. To investigate the dynamic interrelations between involved stakeholders, applied knowledge types and related artefacts, researchers at the TU Berlin conducted and evaluated a student experiment to study basic phenomena of development projects. In relation to research methods and instruments applied in this experiment, various improvement opportunities were identified. In this paper, the experimental setting and its results are critically analysed from a social science perspective in order to generate improved research design. Based on the results of this analysis, a first set of methods and instruments from social sciences are identified that can be applied in further experiments. The goal is to develop a methodological toolbox that can be used to approach research on knowledge dynamics in product development.
  • Publication
    Leveraging circular economy through a methodology for smart service systems engineering
    ( 2019)
    Halstenberg, F.A.
    ;
    Lindow, K.
    ;
    Stark, R.
    Product Service Systems (PSS) and Smart Services are powerful means for deploying Circular Economy (CE) goals in industrial practices, through dematerialization, extension of product lifetime and efficiency increase by digitization. Within this article, approaches from PSS design, Smart Service design and Model-based Systems Engineering (MBSE) are combined to form a Methodology for Smart Service Architecture Definition (MESSIAH). First, analyses of present system modelling procedures and systems modelling notations in terms of their suitability for Smart Service development are presented. The results indicate that current notations and tools do not entirely fit the requirements of Smart Service development, but that they can be adapted in order to do so. The developed methodology includes a modelling language system, the MESSIAH Blueprinting framework, a systematic procedure and MESSIAH CE, which is specifically designed for addressing CE strategies and practices. The methodology was validated on the example of a Smart Sustainable Street Light System for Cycling Security (SHEILA). MESSIAH proved useful to help Smart Service design teams develop service-driven and robust Smart Services. By applying MESSIAH CE, a sustainable Smart Service, which addresses CE goals, has been developed.