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SyProLei - A systematic product development process to exploit lightweight potentials while considering costs and CO2 emissions

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Procedia CIRP 2022年 109卷 520-525页

作者： Jerome Kaspar Kristian König Johannes Scholz Steven Quirin Sven Kleiner Jürgen Fleischer Hans-Georg Herrmann Michael Vielhaber :em engineering methods AG Rheinstr. 97 64295 Darmstadt Germany Institute of Engineering Design Saarland University Campus E2 9 66123 Saarbrücken Germany wbk Institute of Production Science Karlsuhe Institute of Technology Kaiserstraße 12 76131 Karlsruhe Germany Chair for Lightweight Systems Saarland University Campus E3 1 66123 Saarbrücken Germany Fraunhofer Institute for Nondestructive Testing IZFP Campus E3 1 66123 Saarbrücken Germany

In lightweight design, developers are used to face the conflicting objectives of functional fulfillment, economic performance, and sustainability. Against this background, however, a clearly structured approach for the satisfied use of specific lightweight engineering methods within the product development is still missing. Thus, this contribution deals with the fundamental conception and first implementation of a systematic development methodology covering the disciplines of mechanics, electrics/electronics and software just like the focus on an integrated view on product, production and material aspects. To ensure an application-specific manifestation of the product development process for three exemplary use cases from small and medium-sized enterprises but also large corporations in the area of prosthetics, bike construction and plant engineering, the individually developed methods and tools are first generalized in order to make them adaptable to a wide variety of industries. As a result, one lightweight-specific method or tool (e.g., function mass analysis, “PPM solution correlator“ or “2D layout & weight drafting”) is introduced in more detail for all stages of the technically extended RFL(T)P approach derived from model-based systems engineering (MBSE).

关键词： lightweight design product development process engineering methods system engineering

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Scanning Acoustic Microscopy for Quantifying Two-phase Transfer in Operando Alkaline Water Electrolyzer

arXiv

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arXiv 2024年

作者： Dou, Zehua Rox, Hannes Ramos, Zyzi Baumann, Robert Ravishankar, Rachappa Czurratis, Peter Yang, Xuegeng Lasagni, Andrés Fabian Eckert, Kerstin Czarske, Juergen Weik, David Faculty of Electrical and Computer Engineering Laboratory of Measurement and Sensor System Technique Technische Universität Dresden Helmholtzstraße 18 Dresden01069 Germany Institute of Fluid Dynamics Helmholtz-Zentrum Dresden-Rossendorf Bautzner Landstraße 400 Dresden01328 Germany PVA TePla Analytical Systems GmbH Deutschordenstraße 38 Westhausen73463 Germany Institute of Manufacturing Science and Engineering Technische Universität Dresden George-Baehr-Straße 3c Dresden01069 Germany Fraunhofer Institute for Material and Beam Technology IWS Winterbergstraße 28 Dresden01277 Germany Institute of Process Engineering and Environmental Technology Technische Universität Dresden Helmholtzstraße 14 Dresden01069 Germany Hydrogen Lab School of Engineering Technische Universität Dresden Helmholtzstraße 14 Dresden01062 Germany Institute for Emerging Electronic Technologies Leibniz Institute for Solid State and Materials Research Dresden Helmholtzstraße 20 Dresden01069 Germany

Improved understandings of two-phase transport in electrochemical gas-evolving systems are increasingly demanded, while high-performance imaging techniques using simplified instrumentations are not readily available. This work presents volumetric scanning acoustic microscopy (SAM) imaging for quantifying the dynamics of gas bubbles and electrolyte in porous Nickel electrodes with different wettability and structures during alkaline water electrolysis (AWE). We realize high-resolution 3D imaging at 10's µm level using high frequency spherically focused ultrasound. The high resolution allowed us to clearly visualize the spatial distributions of produced bubbles in the porous electrodes over time. Moreover, we are able to quantify the residual gas volume in an electrode and its coverage due to bubble evolution, which dominate its transport overpotential. Taking these advantages, we elucidate the impacts of electrodes' wettability and structures on their electrolysis performance, on a regular laboratory base. The obtained knowledge provides us important optimization guidelines of AWE designs and operating schemes. Copyright © 2024, The Authors. All rights reserved.

关键词： Mass transfer

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Strain measurement by contour analysis

arXiv

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arXiv 2022年

作者： Ganzenmüller, Georg C. Jakkula, Puneeth Hiermaier, Stefan Albert-Ludwigs-Universität Freiburg Institute for Sustainable Systems Engineering INATECH Emmy-Noether Str. 2 Freiburg79110 Germany Fraunhofer Institute for High-Speed Dynamics Ernst-Mach-Institut EMI Ernst-Zermelo Str. 4 Freiburg79104 Germany

Background: The determination of yield stress curves for ductile metals from uniaxial material tests is complicated by the presence of tri-axial stress states due to necking. A need exists for a straightforward solution to this problem. Objective: This work presents a simple solution for this problem specific to axis-symmetric specimens. Equivalent uniaxial true strain and true stress, corrected for triaxiality effects, are calculated without resorting to inverse analysis methods. Methods: A computer program is presented which takes shadow images from tensile tests, obtained in a backlight configuration. A single camera is sufficient as no stereoscopic effects need to be addressed. The specimen’s contours are digitally extracted, and strain is calculated from the contour change. At the same time, stress triaxiality is computed using a novel curvature fitting algorithm. Results: The method is accurate as comparison with manufactured solutions obtained from Finite Element simulations show. Application to 303 stainless steel specimens at different levels of stress triaxiality show that equivalent uniaxial true stress – true strain relations are accurately recovered. Conclusions: The here presented computer program solves a long-standing challenge in a straightforward manner. It is expected to be a useful tool for experimental strain analysis. © 2022, CC BY-NC-SA.

关键词： Tensile testing

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A hybrid source of quantum light for generation of frequency tunable Fock states

arXiv

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arXiv 2024年

作者： Krstić, Aleksa Tiwari, Priyanshu Höhe, Florian Setzpfandt, Frank Peschel, Ulf Ankerhold, Joachim Saravi, Sina Institute of Applied Physics Abbe Center of Photonics Friedrich-Schiller University Jena Albert-Einstein-Straße 15 Jena07745 Germany Institute for Complex Quantum Systems and IQST University of Ulm Albert-Einstein-Allee 11 Ulm89069 Germany Fraunhofer Institute for Applied Optics and Precision Engineering Albert-Einstein-Straße 7 Jena07745 Germany Institute of Condensed Matter Theory and Solid State Optics Friedrich-Schiller University Jena Max-Wien-Platz 1 Jena07743 Germany

We propose a scheme for quantum-light generation in a nonlinear cavity hybridized with a 2-level system and theoretically show that, when excited by a series of controlled pump pulses, the hybrid source generates Fock states with high probabilities. E.g., 1- and 2-photon states can be generated near-on-demand, and Fock states with up to 7 photons with a probability above 50%. The tailorable nature of the nonlinear cavity allows for generating Fock states with arbitrary frequencies, even with a fixed 2-level system, creating fundamentally new opportunities in all areas of quantum technologies. © 2024, CC BY.

关键词： Two photon processes

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Transferring experience from simulation to the real world for precise pick-and-place tasks in highly cluttered scenes

arXiv

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arXiv 2021年

作者： Kleeberger, Kilian Völk, Markus Moosmann, Marius Thiessenhusen, Erik Roth, Florian Bormann, Richard Huber, Marco F. Department Robot and Assistive Systems Fraunhofer Institute for Manufacturing Engineering and Automation IPA Nobelstraße 12 Stuttgart70569 Germany Fraunhofer Institute for Manufacturing Engineering and Automation IPA Nobelstraße 12 Stuttgart70569 Germany Institute of Industrial Manufacturing and Management IFF University of Stuttgart Allmandring 35 Stuttgart70569 Germany

In this paper, we introduce a novel learning-based approach for grasping known rigid objects in highly cluttered scenes and precisely placing them based on depth images. Our Placement Quality Network (PQ-Net) estimates the object pose and the quality for each automatically generated grasp pose for multiple objects simultaneously at 92 fps in a single forward pass of a neural network. All grasping and placement trials are executed in a physics simulation and the gained experience is transferred to the real world using domain randomization. We demonstrate that our policy successfully transfers to the real world. PQ-Net outperforms other model-free approaches in terms of grasping success rate and automatically scales to new objects of arbitrary symmetry without any human intervention. Copyright © 2021, The Authors. All rights reserved.

关键词： Machine learning

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Investigation of high-depostition-rate additive manufacturing of Ti-6Al-4V via laser material deposition 24

Investigation of high-depostition-rate additive manufacturin...

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24th International ESAFORM Conference on Material Forming, ESAFORM 2021

作者： Hama-Saleh, Rebar Yildirim, Kerim Hemes, Susanne Weisheit, Andreas Häfner, Constantin Leon Fraunhofer Institute for Laser Technology - ILT Steinbach Straße 15 AachenD-52074 Germany Manufacturing Processes and Systems Department of Mechanical Engineering KU Leuven Celestijnenlaan 300 -box 2420 Leuven3001 Belgium ACCESS e.V. Intzestraße 5 AachenD-52072 Germany

ISBN: (纸本)9782870193020

Ti-6Al-4V is the most prominent titanium alloy widely used e.g. for aerospace applications. Conventionally, many Ti-6Al-4V aerospace components are produced by a multi-stage hot forging process followed by subsequent machining which often generates a high amount of scrap. Additive manufacturing (AM), such as powder-based laser material deposition (p-LMD), enables parts to be made with geometric freedom and near-net-shape, but so far lacks high deposition rates. The present study proposes high-deposition-rate laser material deposition manufacturing using a large laser beam diameter and increased scanning speed to achieve deposition rates up to 5 kg/h. As Ti-6Al-4V is prone to oxygen pick-up, the process was performed in an inert atmosphere. We determined suitable process windows for tracks without fusion defects and low porosity and investigated microstructure and hardness. © ESAFORM 2021 - 24th Inter. Conf. on Mat. Forming. All rights reserved.

关键词： Aluminum alloys

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Environmental and technical evaluation of additive manufacturing: Enabling process chain perspective by energy value stream mapping

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Procedia CIRP 2022年 105卷 440-445页

作者： Mathias Wiese Christopher Rogall Nadja Henningsen Christoph Herrmann Sebastian Thiede Polymer Additive Manufacturing Center AUDI AG Auto-Union-Straße 1 Ingolstadt 85045 Germany Chair of Sustainable Manufacturing and Life Cycle Engineering Institute of Machine Tools and Production Technology Technische Universität Braunschweig Langer Kamp 19b Braunschweig 38106 Germany Fraunhofer Institute for Surface Engineering and Thin Films (IST) Bienroder Weg 54 E Braunschweig 38108 Germany Manufacturing Systems Faculty of Engineering Technology Department of Design Production & Management University of Twente De Horst 2 Building 20 Enschede 7522 LW The Netherlands

Additive manufacturing (AM) currently evolves from a prototyping process to an alternative manufacturing process for end-use parts, advancing into fabrication of low to medium product volumes. Moreover, increasing awareness of environmental impacts of manufacturing lead to the necessity of holistic evaluation among traditional evaluation criteria in the technical and economic domains. However, existing evaluation approaches seldom consider a complete AM process chain and are lacking a production-oriented notation which enables comparability across technologies and support in identification of improvement potentials on technical and environmental level. To address this gap, this paper highlights the way from structured data acquisition to setup of an energy value stream map (EVSM) for AM process chains in end-use part production, augmenting methods of lean manufacturing by the energy dimension. Consequently, it contributes to a holistic and transparent process chain perspective to assess AM as a manufacturing alternative. The proposed methodology is applied to a case study covering two different process chains, a first based on powder bed fusion via Multi-jet Fusion (MJF) and a second utilizing vat-photopolymerization via Continuous Liquid Interphase Printing (CLIP). While the MJF process chain’s energetical hot spot is situated in the printing process itself, the hot spot for CLIP is found in thermal post-processing, exceeding the comparably efficient printing process by magnitudes and ultimately resulting in higher energy intensity per part compared to the MJF process chain. These results highlight the necessity of a holistic evaluation method for complete AM-based process chains and their influence on the product properties. Insights may help engineers, designers and decision makers in pre-selection of suitable manufacturing strategies with a more complete view on AM process chains.

关键词： Additive manufacturing rapid manufacturing process chains value stream mapping sustainable manufacturing decision support

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Stochastic noise can be helpful for variational quantum algorithms

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Physical Review A 2025年第5期111卷 052441-052441页

作者： Junyu Liu Frederik Wilde Antonio Anna Mele Xin Jin Liang Jiang Jens Eisert Pritzker School of Molecular Engineering The University of Chicago Chicago Illinois 60637 USA School of Computing and Information University of Pittsburgh Pittsburgh Pennsylvania 15260 USA Chicago Quantum Exchange Chicago Illinois 60637 USA Kadanoff Center for Theoretical Physics The University of Chicago Chicago Illinois 60637 USA Dahlem Center for Complex Quantum Systems Freie Universität Berlin Berlin 14195 Germany Electrical Engineering and Computer Science Technische Universität Berlin Berlin 10587 Germany Helmholtz-Zentrum Berlin für Materialien und Energie Berlin 14109 Germany Fraunhofer Heinrich Hertz Institute Berlin 10587 Germany

Saddle points constitute a crucial challenge for first-order gradient descent algorithms. In notions of classical machine learning, they are avoided, for example, by means of stochastic gradient descent methods. In this work, we provide evidence that the saddle-points problem can be naturally avoided in variational quantum algorithms by exploiting the presence of stochasticity. We prove convergence guarantees and present practical examples in numerical simulations and on quantum hardware. We argue that the natural stochasticity of variational algorithms can be beneficial for avoiding strict saddle points, i.e., those saddle points with at least one negative Hessian eigenvalue. This insight that some levels of shot noise could help is expected to add a new perspective to notions of near-term variational quantum algorithms.

关键词： Variational techniques

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One T Gate Makes Distribution Learning Hard

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Physical Review Letters 2023年第24期130卷 240602-240602页

作者： M. Hinsche M. Ioannou A. Nietner J. Haferkamp Y. Quek D. Hangleiter J.-P. Seifert J. Eisert R. Sweke Dahlem Center for Complex Quantum Systems Freie Universität Berlin 14195 Berlin Germany Joint Center for Quantum Information and Computer Science (QuICS) University of Maryland and NIST College Park Maryland 20742 USA Department of Electrical Engineering and Computer Science TU Berlin 10587 Berlin Germany Helmholtz-Zentrum Berlin für Materialien und Energie 14109 Berlin Germany Fraunhofer Heinrich Hertz Institute 10587 Berlin Germany

The task of learning a probability distribution from samples is ubiquitous across the natural sciences. The output distributions of local quantum circuits are of central importance in both quantum advantage proposals and a variety of quantum machine learning algorithms. In this work, we extensively characterize the learnability of output distributions of local quantum circuits. Firstly, we contrast learnability with simulatability by showing that Clifford circuit output distributions are efficiently learnable, while the injection of a single T gate renders the density modeling task hard for any depth d=nΩ(1). We further show that the task of generative modeling universal quantum circuits at any depth d=nΩ(1) is hard for any learning algorithm, classical or quantum, and that for statistical query algorithms, even depth d=ω[log(n)] Clifford circuits are hard to learn. Our results show that one cannot use the output distributions of local quantum circuits to provide a separation between the power of quantum and classical generative modeling algorithms, and therefore provide evidence against quantum advantages for practically relevant probabilistic modeling tasks.

关键词： Machine learning Quantum computation Quantum computing models Quantum gates

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Developing and evaluating concepts for a digital platform 28

Developing and evaluating concepts for a digital platform

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28th International Conference for the International Association of Management of Technology: Managing Technology for Inclusive and Sustainable Growth, IAMOT 2019

作者： Wortmann, Fabio Joppen, Robert Drewel, Marvin Kühn, Arno Dumitrescu, Roman Fraunhofer-Institute for Mechatronic Systems Design IEM Germany University of Paderborn Advanced Systems Engineering Germany Fraunhofer-Institute for Mechatronic Systems Design IE Germany University of Paderborn Advanced Systems Engineering Germany

ISBN: (纸本)9789388237543

No other area shows such a potential for disruption as digital platforms. B2C platforms, like Amazon and Uber, have radically changed the market situations within their industry. Until today, this change has mainly taken place in the B2C sector. Still, first platforms are already established in the B2B sector. Examples are Adamos in manufacturing and 365FarmNet in agriculture. With the entrance into the platform economy, companies are confronted with huge challenges. One question is whether a platform can be established in a certain industry due to its specific characteristics. Further questions are how a promising overall platform concept looks like, what relevant platform services are and who the essential actors on the platform are. In literature, there are different approaches for describing the benefits of a platform and designing a basic platform setup. Examples are the Platform Design Toolkit and Platform Value Canvas, which can be used for describing a platforms value proposition. Another example is the Platform Shell Model to describe the stakeholders of a platform. Still, those methods do not help companies to create a basis for decision-making for a platform strategy. In this paper we present a method for developing and evaluating concepts of a digital platform. Based on our project experience, we derived a thorough procedure complemented with adequate methods to do so. The starting point is the question of how a company should act regarding platforms in a certain industry. The goal is to develop platform concepts and to provide an initial evaluation. All relevant actors of an industry and their pains and gains should be considered. The platform concepts are based on the assumption that a platform can be described by its services and actors. The services should also be bundled into clusters with regard to their synergies in order to obtain consistent concepts. The validation shows that different platform concepts are promising depending on the ecosystem.

关键词： Decision making

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