检索结果-内蒙古大学图书馆

Infrared-based Detection of Porosity Formation in Laser-based Powder Bed Fusion of Ti6Al4V

Procedia CIRP 2025年 134卷 443-448页

作者： Eckart Uhlmann Gustavo Reis de Ascencao Bernhard Hesse Jussi-Petteri Suuronen Paul Helmerking David Carlos Domingos Fraunhofer Institute for Production Systems and Design Technology (IPK) Pascalstraße 8-9 10587 Berlin Germany Technische Universität Berlin – Institute for Machine Tools and Factory Management (IWF) Pascalstraße 8-9 Berlin 10587 Germany XPLORAYTION GmbH Invalidenstraße 34 10115 Berlin Germany

The prospects of a broad industrial adoption of additive manufacturing technologies are strongly dependent on the capability of manufacturing systems to consistently deliver high quality parts. While closed loop control is still in its infancy, the in-situ identification of defects is currently of scientific and industrial interest. Radiative measurements have been gaining ground in the monitoring of laser-based powder bed fusion of Metals due to key features that can be extracted from the melt pool and surrounding regions. This paper presents an investigation of the use of high-speed short-wave infrared imaging and photodiodes for the detection of porosity formation in Ti6Al4V parts during processing. The formation of sparks and the material cooldown information are geometrically registered to micro computed tomography data of each sample, building a labelled database for the development of a logistic regression-based porosity prediction model. The model performance is assessed for low, mid, and high energy processing conditions, resulting in F1-scores between 0.51 and 0.81 for the classification of layers, depending on the dataset used for training and testing as well as on the defect threshold selected for binary labelling.

关键词： Additive Manufacturing Laser-based Powder Bed Fusion of Metals PBF-LB/M Process Monitoring Thermography Computed Tomography CT

来源：评论

学校读者我要写书评

暂无评论

ENHANCING THE EUROPEAN ENTREPRENEURIAL ECOsystem BY CLOSING THE GAP BETWEEN HIGH AND LOW/MODERATE INNOVATION REGIONS: THE ENTREPRENEDU CASE 74

ENHANCING THE EUROPEAN ENTREPRENEURIAL ECOSYSTEM BY CLOSING ...

引用

74th International Astronautical Congress, IAC 2023

作者： Roscani, Valerio Scatena, Lorenzo Lombardi, Eleonora Barlas, Achilleas Singer-Coudoux, Katrin Buxmann, Henry Nicolai Fernández, Abel Fondazione E. Amaldi c/o Italian Space Agency Rome Italy The Business Applications Department Fondazione E. Amaldi c/o Italian Space Agency Rome Italy University of Thessaly Volos Greece Fraunhofer Institute for Production Systems and Design Technology IPK Berlin Germany EU Projects Director EBAN Brussels Belgium

The European entrepreneurial ecosystems are facing increasing global competition, nevertheless closing the innovation gap among European countries and regions is still a necessity to provide education schemes and supporting mechanisms for youth and startups. Technologically driven sectors such as spacetech and deeptech are well suited for innovation but new entrepreneurs, students and researchers often lack the necessary know-how to build a resilient and successful business. To provide the right expertise, support the birth of innovative ideas and ultimately strengthen entrepreneurial ecosystems the project ENTREPRENEDU - Enhancing Entrepreneurial Ecosystems for Education - brings together several innovation stakeholders and educational entities from 6 different European countries, 3 low/moderate innovative regions Italy, Bulgaria and Greece and 3 high innovative regions Belgium, Germany and Ireland. ENTREPRENEDU - is a Horizon Europe financed programme, coordinated by Fondazione E. Amaldi, that aims to create a more innovative, entrepreneurial and sustainable European higher education system. The project is conceived for students, young entrepreneurs and start-ups working in the space economy, deep tech and green and digital transition and aims at creating a high replicable and scalable Venture Building Program for both businesses and educational systems via a series of 3 Hackathons, developed at regional level, supporting developed concept and ideas to become concrete solutions. ENTREPRENEDU aims to foster the birth of innovative ideas that will have an impact on both the Green Deal and the SDGs, as well as on gender equality with the goal of having concrete projects for a better and more sustainable world. The goal of this paper is to illustrate the best practices regarding the structuring and implementation of the scalable and replicable ENTREPRENEDU Venture Building programme. This study will present the results of the first hackathon focusing on deeptech, the

关键词： business acceleration entrepreneurship hackathon innovation ecosystems mentoring venture building

来源：评论

学校读者我要写书评

暂无评论

End-of-life decision support to enable circular economy in the automotive industry based on digital twin data

引用

Procedia CIRP 2023年 119卷 1071-1077页

作者： Janine Mügge Inka Rebekka Hahn Theresa Riedelsheimer Johannes Chatzis Joachim Boes Fraunhofer Institute for Production Systems and Design Technology IPK Pascalstraße 8-9 10587 Berlin Germany tec4U-Ingenieurgesellschaft mbH Saar-Lor-Lux-Straße 15 66115 Saarbrücken Germany

With the EU Green Deal and the UN Sustainable Developments Goals, the vision of a greenhouse gas-neutral and resource-efficient economy is already firmly anchored in world politics. In this context, the automotive industry faces many challenges including the increasing scarcity of natural resources, a rising demand in terms of sustainable vehicle design, production and materials sourcing. Due to all this, end-of-life decisions regarding dismantling have become increasingly important. A high proportion of secondary materials will be required in the vehicles of the future. To response to these challenges, companies have turned their focus towards the circular economy as a central approach to close material loops. In the German research project “Catena-X” a new data ecosystem with digital twins is one enabler that is being developed. The digital twins represent a promising approach to the circular economy by ensuring transparent, product-specific and end-to-end data exchange throughout the entire product lifecycle, from the material sourcing to the eventual dismantling and recycling. As one particular and unique solution, a decision framework that facilitates the best circular strategy at the end of a vehicle's life is developed and presented in this paper. The underlying data-driven decision support framework is based on circular economy KPIs. This includes material, components and specific vehicle KPIs to best identify the most suitable circular strategy. The framework was methodologically developed by an interdisciplinary team of partners, who are stakeholders throughout the value chain and participants in the Catena-X project. An integrated approach of user-centered design, an adapted version of the V-model and the Scaled Agile Framework were used for the methodology in the development of the solution. The paper presents the concept of a digital twin for a decision support system, that includes a central decision logic that also includes the relevant KPIs and a sur

关键词： Digital Twin Circular Economy Sustainability Catena-X Decision Support

来源：评论

学校读者我要写书评

暂无评论

Prediction of Quality in Thermographic Spray Spot Applications with Machine Learning Algorithms

引用

Procedia CIRP 2023年 120卷 1215-1219页

作者： Eckart Uhlmann Julian Polte Nikolaos-Stefanos Koutrakis Lasse Pyka Müslüm Ider Georg Thomas Christian Rupprecht Fraunhofer Institute for Production Systems and Design Technology IPK Pascalstraße 8-9 10587 Berlin Germany Institute for Machine Tools and Factory Management (IWF) Technische Universität Berlin Pascalstraße 8-9 Berlin 10587 Germany

Due to the high number of influences in production applications, quality fluctuation and deviating results in thermal spray applications are a challenging issue in manufacturing processes. This paper presents a concept for an adaptive process control based on different machine learning algorithms that are utilized to correlate input parameters with output results in thermal spray processes. For that purpose, a test environment was developed, incorporating different application scenarios with various input parameters. During the experiments, a series of measurements was performed, that is used to describe and evaluate the process. The extracted data of the conducted experiments are transformed into features and serve as the data input for the development of machine learning models based on various algorithms. These algorithms offer a prediction of the peak position, which describes the deviation of the programmed application spot, thus offering a quality prediction by utilizing solely the input process parameters. This work provides an approach based on the compared algorithms, that can be applied to create an adaptive process control, by adjusting the input parameters during the thermal spray application process.

关键词： Machine learning thermal spray process quality prediction process control

来源：评论

学校读者我要写书评

暂无评论

Characterization and investigation of binderless nanopolycrystalline diamond turning tools for precision machining 22

Characterization and investigation of binderless nanopolycry...

引用

22nd International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2022

作者： Uhlmann, E. Sturm, H. Polte, M. Hocke, T. Polte, C. Polte, J. Institute for Machine Tools and Factory Management IWF Technische Universität Berlin Pascalstr. 8-9 Berlin10587 Germany Fraunhofer Institute for Production Systems and Design Technology IPK Pascalstr. 8-9 Berlin10587 Germany Unter den Eichen 87 Berlin12205 Germany

ISBN: (纸本)9781998999118

Cemented carbide is used in a wide range of industrial applications as a wear-resistant material, e.g. in mould making and forming industry. At state of the art, the machining of cemented carbide is severely limited because of the hardness, high strength and the resulting wear resistance of the material. Due to the brittle-hard character cemented carbide materials suffer from surface cracks during the machining. The brittle-hard character and the related phenomena result in high tool wear. A promising approach for the machining of cemented carbide is the use of the novel cutting material binderless nanopolycrystalline diamond (NPD) with a dedicated cutting edge design. Within this work, laser machined tools with a corner radius of r?= 400 µm are fully characterized, investigated by Raman spectroscopy regarding the condition of the diamond and applied for first cutting experiments. Cutting investigations were carried out using specimens with a tungsten carbide content of cC = 88 %, a cobalt content of cCo= 12 % and a grain size of dg= 0.5 µm. Prior to these investigations, the condition of the diamonds and possible changes due to the lasered cutting edges were examined by Raman spectroscopy. During the cutting investigations, the brittle-ductile transition as well as the minimum chip thickness were identified by scratching tests. It could be shown that a hydrostatic stress state can be used to achieve ductile chip formation using cemented carbide as workpiece material. © European Society for Precision Engineering and Nanotechnology, Conference Proceedings - 22nd International Conference and Exhibition, EUSPEN 2022. All rights reserved.

关键词： Tungsten carbide

来源：评论

学校读者我要写书评

暂无评论

Tool wear prevention in ultra-precision polymer machining 20

Tool wear prevention in ultra-precision polymer machining

引用

20th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2020

作者： Uhlmann, E. Fang, F. Polte, J. Hein, C. Lai, M. Dörr, M. Jahnke, C. Fraunhofer Institute for Production Systems and Design Technology IPK Germany Tianjin University China

ISBN: (纸本)9780995775176

Polymers become more relevant in the field of optical components as their optical properties, like refractive index n and wavelength dependent dispersion n = f(λ), can be adjusted easily by additives. Due to their low density ρ polymeric optics are lightweight compared to glasses. The demand for ultra-precision machined polymer lenses is increasing. Small series and individualised components can only be produced economically by using ultra-precision machining. Within theses studies the influence of different measures to reduce diamond tool wear occurring during ultra-precision diamond face turning of polycarbonate (PC) and polysulfone (PSU) will be investigated. Continuous and interrupted face turning experiments are conducted to analyse the effects from separation of the diamond tool and workpiece. Results show increasing tool wear in interrupted cutting. Changes of the environmental conditions in the cutting process show an influence of increasing humidity H on diamond tool wear. This contribution gives a qualitative and quantitative overview on the influencing factors on diamond tool wear in ultra-precision turning of polymers and gives an outlook on strategies to avoid its occurrence. Copyright © Proceedings of the 20th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2020. All rights reserved.

关键词： Turning

来源：评论

学校读者我要写书评

暂无评论

Constructive compensation of the thermal behaviour for industrial robots 13

Constructive compensation of the thermal behaviour for indus...

引用

13th International DAAAM Baltic Conference and 29th International Baltic Conference, BALTMATTRIB 2021

作者： Uhlmann, Eckart Polte, Julian Mohnke, Christian Fraunhofer Institute for Production Systems Design Technology IPK Pascalstraße 8-9 Berlin10587 Germany Institute of Machine Tools and Factory Management Pascalstraße 8-9 Berlin10587 Germany

Industrial robot systems offer a flexible, adaptable basis due to their kinematics and their mobility An influencing variable, which is particularly relevant for processes with long process times, is the thermal heating and the associated thermal drift of the tool center point. The maximum deviation from the actual nominal position can reach up to ΔAPt = 1.5 mm. Currently, there are no procedures and methods established in practice which compensate the effects of thermal drift without expensive calibration measures and system downtime. In these investigations a system was developed which allows the reduction of thermally induced displacement by using controlled heating elements. The aim is to keep the entire robot system at a permanent, balanced temperature level. The heating elements are adapted to the geometry of the respective axis and heat the material to a temperature ϑ close to the steady state. A comparison of the drift through the heating system with the error occurring in normal operation shows that the drift of the heating system is comparable with the drift of normal heating. With the heating mats, a thermally induced error of ΔAPt = 0.234 mm can be generated within t = 20 min. While normal heating requires up to t = 600 min. The achieved error deviation of the drift of the self-heating to the heated variants is with ΔAP = 0.04 mm only minimal. The results can help to reduce the influence of thermal heating and the associated thermal drift of the TCP without using cost-intensive measures with additional hardware and software on external computers for compensating the errors. © 2021 DAAAM International. All rights reserved.

关键词： Industrial robots

来源：评论

学校读者我要写书评

暂无评论

Biological transformation: Principles to enhance holistic production systems

引用

Procedia CIRP 2022年 110卷 293-298页

作者： Annika Lange Thomas Knothe Holger Kohl Günther Seliger Fraunhofer Institute for Production Systems and Design Technology IPK Pascalstraße 8-9 10587 Berlin Germany Technische Universität Berlin Pascalstraße 8-9 10587 Berlin Germany

In today’s production systems, the digital transformation is fully in progress. But the next evolution step can be seen on the horizon, biological transformation. This means the application of biomimetics principles with the aim of low-effort, resource-saving, reversible and adapted economies. Because of their aim regarding minimization of resource consumption and stability orientation even in turbulent environments, biomimetics principles can contribute to the major challenges of production systems, climate change, environmental protection, as well as the turbulences as generated by globalization and individualization in this paper it is described how biological transformation can contribute to extend and improve holistic production systems. For this purpose, traditional principles of holistic production systems are reflected with the ones coming from digitization and biomimetics.

关键词： Holistic production systems biological transformation characteristics transformation

来源：评论

学校读者我要写书评

暂无评论

Application of Uncertainty-Aware Sensor Fusion in Physical Sensor Networks

Application of Uncertainty-Aware Sensor Fusion in Physical S...

引用

IEEE Instrumentation and Measurement technology Conference

作者： Maximilian Gruber Wenzel Pilar von Pilchau Varun Gowtham Nikolaos-Stefanos Koutrakis Nicolas Schö nborn Sascha Eichstä dt Jö rg Hä hner Marius-Iulian Corici Thomas Magedanz Julian Polte Eckart Uhlmann Metrology for Digital Transformation Physikalisch-Technische Bundesanstalt Berlin Germany Organic Computing Group University of Augsburg Augsburg Germany Software-Based Networks Fraunhofer FOKUS Berlin Germany Production Machines and System Management Fraunhofer Institute for Production Systems and Design Technology IPK Berlin Germany TTD Technology Development Endress+Hauser Level+Pressure Maulburg Germany Organic Computing Group University of Augsburg Berlin Germany Production Systems Fraunhofer Institute for Production Systems and Design Technology IPK Berlin Germany

Modern industrial processes often collect redundant information from multiple sensors. It is of interest to leverage this information to form a more accurate or robust estimate of an observed quantity utilizing a sensor fusion operation. To be able to comply with quality requirements on the fused value, preservation of traceability is required. Moreover, the sensor fusion needs to be implemented within suitable digital architectures for Industrial Internet of Things (IIoT) environments. In a continuation of previous work, this is achieved by the usage of digital twins that represent the entities of two IIoT testbeds and the adoption of a method for uncertainty-aware homogeneous sensor fusion, which is presented in full detail. Metrological traceability of the fused value is established by propagating the measurement uncertainty of the input sensor according to metrological standards. The method is implemented as a modular service connected to an existing IIoT architecture. The flexibility of the method is shown by application to two different scenarios with only minimal adaption efforts. The fused sensor values are (as indicated by earlier work) robust to outliers and perform well in practical scenarios within the chosen IIoT architecture.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Holistic Concept towards a Reference Architecture Model for Predictive Maintenance 54

Holistic Concept towards a Reference Architecture Model for ...

引用

54th CIRP Conference on Manufacturing Ssystems, CMS 2021

作者： Uhlmann, Eckart Polte, Julian Koutrakis, Nikolaos-Stefanos Fraunhofer Institute for Production Systems and Design Technology IPK Pascalstraße 8-9 Berlin10587 Germany Technische Universität Berlin Pascalstraße 8-9 Berlin10587 Germany

In the era of digital transformation of factories, one of the most challenging applications of the Industrial Internet of Things (IIoT) is predictive maintenance. This paper presents a holistic concept for predictive maintenance together with a reference architecture that includes data acquisition on the sensor level, edge computing and digital twin applications. For that purpose, condition-based maintenance, lifecycle monitoring and digital assistance systems are integrated to develop application-specific digital twins based on the proposed architecture, integrating heterogenous data sources in order to enhance the accuracy of the machine learning models. The concept is illustrated through an experimental use case. © 2021 The Author(s).

关键词： Data acquisition

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：