Now showing 1 - 10 of 37
  • Publication
    Methodology for a reverse engineering process chain with focus on customized segmentation and iterative closest point algorithms
    ( 2022) ;
    Schröder, Robert
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    Stark, Rainer
    One-off construction is characterized by a multiplicity of manual manufacturing processes whereby it is based on consistent use of digital models. Since the actual state of construction does not match the digital models without manually updating them, the authors propose a method to automatically detect deviations and reposition the model data according to reality. The first essential method is based on the ""Segmentation of Unorganized Points and Recognition of Simple Algebraic Surfaces"" presented by Vanco et al.. The second method is the customization of the iterative closest point (ICP) algorithm. The authors present the overall structure of the implemented software, based on open source and relate it to the general reverse engineering (RE) framework by Buonamici et al.. A highlight will be given on: the general architecture of the software prototype; a customized segmentation and clustering of unorganized points and recognition of simple algebraic surfaces; the deviation analysis with a customized iterative closest point (CICP) algorithm Especially in the field of one-off construction, characterized by small and medium companies, automated assessment of 3D scan data during the design process is still in its infancy. By using an open source environment progress for consistent use of digital models could be accelerated.
  • Publication
    Literature review of quality attributes for collaborative product development
    ( 2022)
    Randermann, Marcel
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    Jochem, Roland
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    Stark, Rainer
    In collaborative product development, diverse stakeholders are involved in distributed engineering activities. This situation makes it difficult to ensure, manage, and improve the quality across company boundaries. Therefore, this work determines the characteristics of collaborative engineering which have an influence on the quality of distributed product development. Several interoperability frameworks were analyzed in order to get insights into key areas for collaboration design. Furthermore, a systematic literature review provided the best practices for improvement efforts. The derived quality attributes were condensed and adapted to collaborative product development in the four key areas of organization and processes, data/artifacts, information technology systems and infrastructure, and social factors. This enables product developers to examine their collaborative engineering environment and to identify room for improvement and to enhance quality. A case example of an engineering change order shows a collaborative data flow process, in which the quality attributes may indicate improvement measures.
  • Publication
    Knowledge transfer and engineering methods for smart-circular product service systems
    ( 2021)
    Halstenberg, Friedrich
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    Dönmez, Jasmin
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    Mennenga, Mark
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    Herrmann, Christoph
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    Stark, Rainer
    Smart Product Service Systems (Smart PSS) have the potential to contribute to a Circular Economy (CE), but in the design of these systems engineering teams often lack information and knowledge on CE strategies and processes. Against this background, the authors propose a knowledge transfer system for the design of Smart-circular PSS. The system can be used in the concept phase of the Smart PSS development process and delivers information on CE strategies via a Smart-circular PSS Lifecycle Flowchart (SCPLF) and service archetypes. These strategies can be selected, supplemented and extended according to individual user requirements. The approach was validated using an intelligent street lighting system. This paper summarizes findings from the application and provides insights into potentials and limitations for the design of Smart-circular Smart PSS.
  • Publication
    How Pedestrians Perceive Autonomous Buses: Evaluating Visual Signals
    ( 2021) ;
    Kozachek, Diana
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    Konkol, Kathrin
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    Woelfel, Christiane
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    Stark, Rainer
    With the deployment of autonomous buses, sophisticated technological systems are entering our daily lives and their signals are becoming a crucial factor in human-machine interaction. The successful implementation of visual signals requires a well-researched human-centred design as a key component for the new transportation system. The autonomous vehicle we investigated in this study uses a variety of these: Icons, LED panels and text. We conducted a user study with 45 participants in a virtual reality environment in which four recurring communication scenarios between an autonomous driving bus and its potential passengers had to be correctly interpreted. For our four scenarios, efficiency and comprehension of each visual signal combination was measured to evaluate performance on different types of visual information. The results show that new visualization concepts such as LED panels lead to highly variable efficiency and comprehension, while text or icons were well ac cepted. In summary, the authors of this paper present the most efficient combinations of visual signals for four reality scenarios.
  • Publication
    Characterization and application of assistance systems in digital engineering
    ( 2021)
    Stark, Rainer
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    A broad range of assistance systems can be found in manufacturing practice as well as in the corresponding literature. Similarly, it can be observed that there is a growing need for and an increasing supply of assistance systems of all kinds. However, for digital manufacturing, the assistance systems are not clearly characterized. The diversity in application areas and possible uses varies and there are no possibilities for comparison. This paper addresses the topic of assistance systems and examines the various basic elements of engineering activities in terms of possible types of assistance systems based on research in manufacturing industry. Crucial aspects of assistance capabilities for engineering are elaborated and possible digital approaches are validated based on investigations in the field of aircraft engine design and assembly.
  • Publication
    Automated 3D scan based CAD-repositioning for design and verification in one-off construction
    ( 2021) ;
    Schröder, Robert
    ;
    Stark, Rainer
    The presented engineering discipline one-off construction is characterized by a multiplicity of manual processes. As almost all modern product developments, the manufacture is based on the creation and consistent use of digital models. Quality of underlying data can vary greatly and it is not certain that digital models match the actual state of construction. This can result in the need for rework after production or installation. Especially challenging in the area of premium products, for which high quality, scarce materials are used and tight schedules are defined. If physical products are reworked, the corresponding digital models must be manually maintained. At present, attempts are being made to counteract these late adjustments by means of physical mock-ups or visual inspection of 3D scan data. Such scan data is used for automated adaptation of underlying digital models to the actual state of the physical construction. Existing Point Cloud Library functionalities were adapted and further algorithms were designed. The developed software backend was integrated into the existing software architecture. During the software development, great care was taken to ensure that the backend is based on open source content. The results show significant improvements of the data basis for the subsequent engineering activities. This will lead to a significant reduction of manual effort and rework, ensuring development cycles and even shorten delivery times. It reduces costs in the product creation process and sustainably strengthens confidence in digital models used. It has been shown that automation of design processes can have productivity-enhancing effects in one-off construction.
  • Publication
    Systematic Literature Review of System Models for Technical System Development
    ( 2021)
    Manoury, Marvin Michael
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    Zimmermann, Thomas
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    Stark, Rainer
    In Model-Based Systems Engineering (MBSE) there is yet no converged terminology. The term 'system model' is used in different contexts in literature. In this study we elaborated the definitions and usages of the term 'system model', to find a common definition. We analyzed 104 publications in depth for their usage and definition as well as their meta-data e.g., the publication year and publication background to find some common patterns. While the term is gaining more interest in recent years, it is used in a broad range of contexts for both analytical and synthetic use cases. Based on this, three categories of system models have been defined and integrated into a more precise definition.
  • Publication
    Enabling automated engineering's project progress measurement by using data flow models and digital twins
    ( 2021)
    Ebel, Helena
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    Stark, Rainer
    A significant challenge of managing successful engineering projects is to know their status at any time. This paper describes a concept of automated project progress measurement based on data flow models, digital twins, and machine learning (ML) algorithms. The approach integrates information from previous projects by considering historical data using ML algorithms and current unfinished artifacts to determine the degree of completion. The information required to measure the progress of engineering activities is extracted from engineering artifacts and subsequently analyzed and interpreted according to the project's progress. Data flow models of the engineering process help understand the context of the analyzed artifacts. The use of digital twins makes it possible to connect plan data with actual data during the completion of the engineering project.
  • Publication
    Validation of Immersive Design Parameters in Driving Simulation Environments
    ( 2021)
    Lyga, Yvonne
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    Lau, Merle
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    Stark, Rainer
    Driving simulators are used for the prospective validation of technical systems in the automotive sector. The design of simulation environments can affect drivers and should be considered in investigations of driver-vehicle interactions. The aim of this research is to minimize the gap between driving simulators and real car studies by integrating immersive parameters into simulated driving environments. Stereoscopy, surround sound and motion feedback were analyzed with regard to driver behavior and experience and were then compared to data of a real drive from a previous investigation. The authors conducted a study with N = 48 participants performing a dual-task scenario in a driving simulator. Results reveal significant effects of immersive design parameters on gaze behavior and mental workload. Findings provide guidance for an efficient and cost-effective development of driving simulation environments.
  • Publication
    Methodology to develop Digital Twins for energy efficient customizable IoT-Products
    Products are increasingly individualized and enhanced to be able to communicate, e.g. via Industrial Internet of Things (IoT). However, the impact of products on sustainability (environmental and social) across their life is often not considered and analyzed. IoT-based or smart products, that are able to communicate, generate data, which can be used to monitor and optimize sustainability indicators. The Digital Twin (DT) is a new technological concept which focuses on product individual data collection and analysis. It provides the possibility to make use of the available data and optimize the systems individual sustainability as well as future product generations. However, the design and realization of such a DT requires new approaches and capabilities, which is an identified research gap. Therefore, this paper presents a methodology to develop DTs of physical IoT-based products, the so called DT V-Model with the aim to optimize the systems sustainability, specifically environmental aspects. It is based on the V-model for the development of smart products and is enhanced with additional roles and approaches for DT development. The methodology is described in detail. The result of a development cycle according to the DT-V-Model is a tested concept of a DT, which includes Digital Master (DM) data from the planning phase and Digital Shadow (DS) data from the production, operation and End of Life-phase. For a DT for energy efficiency, the Digital Master model consists of the information and models from the product development phase including the planned production and use phase energy consumption. The Digital Shadow consists of the actual production energy consumption and the use phase energy consumption. The methodology is applied to a use case of an IoT-based consumer product that can be customized to a certain degree by the consumer. A DT is developed to monitor and optimize the products energy efficiency in production and use. The necessary elements of the DT and the capabilities are depicted. The paper shows the feasibility of the methodology for the development of DTs, the necessary adaptions to common approaches for development and the specific characteristics of DT development for the aim of energy efficiency.