TY  - JOUR
A1  - Kunkel, Maximilian Hugo
A1  - Gebhardt, Andreas
A1  - Mpofu, Khumbulani
A1  - Kallweit, Stephan
T1  - Quality assurance in metal powder bed fusion via deep-learning-based image classification
JF  - Rapid Prototyping Journal
Y1  - 2019
U6  - http://dx.doi.org/10.1108/RPJ-03-2019-0066
SN  - 1355-2546
VL  - 26
IS  - 2
SP  - 259
EP  - 266
ER  - 
TY  - JOUR
A1  - Raffeis, Iris
A1  - Adjei-Kyeremeh, Frank
A1  - Vroomen, Uwe
A1  - Westhoff, Elmar
A1  - Bremen, Sebastian
A1  - Hohoi, Alexandru
A1  - Bührig-Polaczek, Andreas
T1  - Qualification of a Ni-Cu alloy for the laser powder bed fusion process (LPBF): Its microstructure and mechanical properties
JF  - Applied Sciences
N2  - As researchers continue to seek the expansion of the material base for additive manufacturing, there is a need to focus attention on the Ni–Cu group of alloys which conventionally has wide industrial applications. In this work, the G-NiCu30Nb casting alloy, a variant of the Monel family of alloys with Nb and high Si content is, for the first time, processed via the laser powder bed fusion process (LPBF). Being novel to the LPBF processes, optimum LPBF parameters were determined, and hardness and tensile tests were performed in as-built conditions and after heat treatment at 1000 °C. Microstructures of the as-cast and the as-built condition were compared. Highly dense samples (99.8% density) were achieved after varying hatch distance (80 µm and 140 µm) with scanning speed (550 mm/s–1500 mm/s). There was no significant difference in microhardness between varied hatch distance print sets. Microhardness of the as-built condition (247 HV0.2) exceeded the as-cast microhardness (179 HV0.2.). Tensile specimens built in vertical (V) and horizontal (H) orientations revealed degrees of anisotropy and were superior to conventionally reported figures. Post heat treatment increased ductility from 20% to 31% (V), as well as from 16% to 25% (H), while ultimate tensile strength (UTS) and yield strength (YS) were considerably reduced.
Y1  - 2020
U6  - http://dx.doi.org/10.3390/app10103401
SN  - 2076-3417
N1  - Special Issue Materials Development by Additive Manufacturing Techniques
VL  - 10
IS  - Art. 3401
SP  - 1
EP  - 15
PB  - MDPI
CY  - Basel
ER  - 
TY  - CHAP
A1  - Braun, Sebastian
A1  - Cheng, Chi-Tsun
A1  - Dowey, Steve
A1  - Wollert, Jörg
T1  - Survey on Security Concepts to Adapt Flexible Manufacturing and Operations Management based upon Multi-Agent Systems
T2  - 2020 IEEE 29th International Symposium on Industrial Electronics (ISIE)
Y1  - 2020
U6  - http://dx.doi.org/10.1109/ISIE45063.2020.9152210
ER  - 
TY  - JOUR
A1  - Franko, Josef
A1  - Du, Shengzhi
A1  - Kallweit, Stephan
A1  - Duelberg, Enno Sebastian
A1  - Engemann, Heiko
T1  - Design of a Multi-Robot System for Wind Turbine Maintenance
JF  - Energies
N2  - The maintenance of wind turbines is of growing importance considering the transition to renewable energy. This paper presents a multi-robot-approach for automated wind turbine maintenance including a novel climbing robot. Currently, wind turbine maintenance remains a manual task, which is monotonous, dangerous, and also physically demanding due to the large scale of wind turbines. Technical climbers are required to work at significant heights, even in bad weather conditions. Furthermore, a skilled labor force with sufficient knowledge in repairing fiber composite material is rare. Autonomous mobile systems enable the digitization of the maintenance process. They can be designed for weather-independent operations. This work contributes to the development and experimental validation of a maintenance system consisting of multiple robotic platforms for a variety of tasks, such as wind turbine tower and rotor blade service. In this work, multicopters with vision and LiDAR sensors for global inspection are used to guide slower climbing robots. Light-weight magnetic climbers with surface contact were used to analyze structure parts with non-destructive inspection methods and to locally repair smaller defects. Localization was enabled by adapting odometry for conical-shaped surfaces considering additional navigation sensors. Magnets were suitable for steel towers to clamp onto the surface. A friction-based climbing ring robot (SMART— Scanning, Monitoring, Analyzing, Repair and Transportation) completed the set-up for higher payload. The maintenance period could be extended by using weather-proofed maintenance robots. The multi-robot-system was running the Robot Operating System (ROS). Additionally, first steps towards machine learning would enable maintenance staff to use pattern classification for fault diagnosis in order to operate safely from the ground in the future.
Y1  - 2020
U6  - http://dx.doi.org/10.3390/en13102552
SN  - 1996-1073
VL  - 13
IS  - 10
SP  - Article 2552
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Cosma, Cosmin
A1  - Kessler, Julia
A1  - Gebhardt, Andreas
A1  - Campbell, Ian
A1  - Balc, Nicolae
T1  - Improving the Mechanical Strength of Dental Applications and Lattice Structures SLM Processed
JF  - Materials
N2  - To manufacture custom medical parts or scaffolds with reduced defects and high mechanical characteristics, new research on optimizing the selective laser melting (SLM) parameters are needed. In this work, a biocompatible powder, 316L stainless steel, is characterized to understand the particle size, distribution, shape and flowability. Examination revealed that the 316L particles are smooth, nearly spherical, their mean diameter is 39.09 μm and just 10% of them hold a diameter less than 21.18 μm. SLM parameters under consideration include laser power up to 200 W, 250–1500 mm/s scanning speed, 80 μm hatch spacing, 35 μm layer thickness and a preheated platform. The effect of these on processability is evaluated. More than 100 samples are SLM-manufactured with different process parameters. The tensile results show that is possible to raise the ultimate tensile strength up to 840 MPa, adapting the SLM parameters for a stable processability, avoiding the technological defects caused by residual stress. Correlating with other recent studies on SLM technology, the tensile strength is 20% improved. To validate the SLM parameters and conditions established, complex bioengineering applications such as dental bridges and macro-porous grafts are SLM-processed, demonstrating the potential to manufacture medical products with increased mechanical resistance made of 316L.
Y1  - 2020
U6  - http://dx.doi.org/10.3390/ma13040905
SN  - 1996-1944
VL  - 13
IS  - 4
SP  - 1
EP  - 18
PB  - MDPI
CY  - Basel
ER  - 
TY  - CHAP
A1  - Braun, Sebastian
A1  - Cheng, Chi-Tsun
A1  - Lai, Chow Yin
A1  - Wollert, Jörg
T1  - Microservice Architecture for Automation - Realization by the example of a model-factory’s manufacturing execution system
T2  - Proceedings of the 23rd World Multi-Conference on Systemics, Cybernetics and Informatics: WMSCI 2019
Y1  - 2019
SP  - 33
EP  - 37
ER  - 
TY  - CHAP
A1  - Gerhards, Benjamin
A1  - Schleser, Markus
A1  - Otten, Christian
T1  - Advancements of mobile vacuum laser welding for industrial thick sheet applications
T2  - Conference Proceedings 72nd IIW Annual Assembly and International Conference, 7-12 July 2019, Bratislava
Y1  - 2019
SP  - 1
EP  - 8
ER  - 
TY  - CHAP
A1  - Gerhards, Benjamin
A1  - Schleser, Markus
A1  - Otten,, Christian
A1  - Schwarz, Alexander
A1  - Gebhardt, Andreas
T1  - Innovative Laser Beam Joining Technology for Additive Manufactured Parts
T2  - Conference Proceedings 72nd IIW Annual Assembly and International Conference, 7-12 July 2019, Bratislava
Y1  - 2019
SP  - 1
EP  - 8
ER  - 
TY  - CHAP
A1  - Eichler, Fabian
A1  - Skupin, Marco
A1  - Thurn, Laura
A1  - Kasch, Susanne
A1  - Schmidt, Thomas
T1  - Operating limits for beam melting of glass materials
T2  - Modern Technologies in Manufacturing (MTeM 2019)
N2  - Laser-based Additive Manufacturing (AM) processes for the use of metals out of the powder bed have been investigated profusely and are prevalent in industry. Although there is a broad field of application, Laser Powder Bed Fusion (LPBF), also known as Selective Laser Melting (SLM) of glass is not fully developed yet. The material properties of glass are significantly different from the investigated metallic material for LPBF so far. As such, the process cannot be transferred, and the parameter limits and the process sequence must be redefined for glass. Starting with the characterization of glass powders, a parameter field is initially confined to investigate the process parameter of different glass powder using LPBFprocess. A feasibility study is carried out to process borosilicate glass powder. The effects of process parameters on the dimensional accuracy of fabricated parts out of borosilicate and hints for the post-processing are analysed and presented in this paper.
Y1  - 2019
U6  - http://dx.doi.org/10.1051/matecconf/201929901004
N1  - MATEC Web of Conferences 299; MTeM 2019
VL  - 299
IS  - Article 01004
ER  - 
TY  - CHAP
A1  - Abbas, Karim
A1  - Thurn, Laura
A1  - Kessler, Julia
A1  - Eichler, Fabian
T1  - Basic research of the consideration of additive manufactured lattice structures under thermoand fluid dynamic loads
T2  - Modern technologies in manufacturing (MTeM 2019)
Y1  - 2019
U6  - http://dx.doi.org/10.1051/matecconf/201929901009
N1  - MATEC Web of Conferences 299; MTeM 2019
VL  - 299
IS  - Article 01009
ER  - 
TY  - CHAP
A1  - Luft, Angela
A1  - Gebhardt, Andreas
A1  - Balc, Nicolae
T1  - Challenges of additive manufacturing in production systems
T2  - Modern technologies in manufacturing (MTeM 2019)
Y1  - 2019
U6  - http://dx.doi.org/10.1051/matecconf/201929901003
N1  - MATEC Web of Conferences 299; MTeM 2019
VL  - 299
IS  - Article 01003
ER  - 
TY  - JOUR
A1  - Panc, Nicolae
A1  - Contiu, Glad
A1  - Bocanet, Vlad
A1  - Thurn, Laura
A1  - Sabau, Emilia
T1  - The influence of cutting technology on surface wear hardness
JF  - Academic Journal of Manufacturing Engineering
Y1  - 2019
SN  - 1583-7904
VL  - 17
IS  - 3
SP  - 205
EP  - 210
ER  - 
TY  - CHAP
A1  - Ulmer, Jessica
A1  - Braun, Sebastian
A1  - Lai, Chow Yin
A1  - Cheng, Chi-Tsun
A1  - Wollert, Jörg
T1  - Generic integration of VR and AR in product lifecycles based on CAD models
T2  - Proceedings of The 23rd World Multi-Conference on Systemics, Cybernetics and Informatics: WMSCI 2019
Y1  - 2019
ER  - 
TY  - JOUR
A1  - Bucur, Alexandru
A1  - Lazarescu, Lucian
A1  - Pop, Grigore Marian
A1  - Achimas, Gheorghe
A1  - Gebhardt, Andreas
T1  - Tribological performance of biodegradable lubricants under different surface roughness of tools
JF  - Academic Journal of Manufacturing Engineering
Y1  - 2019
SN  - 1583-7904
VL  - 17
IS  - 1
SP  - 172
EP  - 178
ER  - 
TY  - JOUR
A1  - Schwarz, Alexander
A1  - Gebhardt, Andreas
A1  - Schleser, Markus
A1  - Popoola, Patricia
T1  - New Welding Joint Geometries Manufactured by Powder Bed Fusion from 316L
JF  - Materials Performance and Characterization 8
Y1  - 2019
U6  - http://dx.doi.org/10.1520/MPC20180096
SN  - 2379-1365
IS  - in press
ER  - 
TY  - CHAP
A1  - Engemann, Heiko
A1  - Badri, Sriram
A1  - Wenning, Marius
A1  - Kallweit, Stephan
T1  - Implementation of an Autonomous Tool Trolley in a Production Line
T2  - Advances in Service and Industrial Robotics. RAAD 2019. Advances in Intelligent Systems and Computing, vol 980
Y1  - 2019
SN  - 978-3-030-19648-6
U6  - http://dx.doi.org/10.1007/978-3-030-19648-6_14
SP  - 117
EP  - 125
PB  - Springer
CY  - Cham
ER  - 
TY  - CHAP
A1  - Rieper, Harald
A1  - Gebhardt, Andreas
A1  - Stucker, Brent
T1  - Process parameters for Selective Laser Melting of AgCu7
T2  - DDMC, Fraunhofer Direct Digital Manufacturing Conference, 3
Y1  - 2016
SN  - 978-3-8396-1001-5
N1  - DDMC, 2016, Fraunhofer Direct Digital Manufacturing Conference, 3rd, Berlin, DE, 2016-03-16 - 2016-03-17
SP  - 171
EP  - 176
PB  - Fraunhofer-Verlag
CY  - Stuttgart
ER  - 
TY  - CHAP
A1  - Franzen, Julian
A1  - Stecken, Jannis
A1  - Pfaff, Raphael
A1  - Kuhlenkötter, Bernd
T1  - Using the Digital Shadow for a Prescriptive Optimization of Maintenance and Operation : The Locomotive in the Context of the Cyber-Physical System
T2  - Advances in Production, Logistics and Traffic
N2  - In competition with other modes of transport, rail freight transport is looking for solutions to become more attractive. Short-term success can be achieved through the data-driven optimization of operations and maintenance as well as the application of novel strategies such as prescriptive maintenance. After introducing the concept of prescriptive maintenance, this paper aims to prove that vehicle-focused applications of this approach indeed have the potential to increase attractiveness. However, even greater advantages can be activated if data from the horizontal network of the vehicle is available. Drawing on the state of the art in research and technology in the field of cyber-physical systems (CPS) as well as digital twins and shadows, our work serves to design a system of systems for the horizontal interconnection of a rail vehicle and to conceptualize a draft for a digital twin of a locomotive.
Y1  - 2019
SN  - 978-3-030-13535-5
U6  - http://dx.doi.org/10.1007/978-3-030-13535-5_19
SP  - 265
EP  - 276
PB  - Springer
CY  - Cham
ER  - 
TY  - CHAP
A1  - Wiesen, Patrick
A1  - Engemann, Heiko
A1  - Limpert, Nicolas
A1  - Kallweit, Stephan
T1  - Learning by Doing - Mobile Robotics in the FH Aachen ROS Summer School
T2  - European Robotics Forum 2018, TRROS18 Workshop
Y1  - 2018
SP  - 47
EP  - 58
ER  - 
TY  - CHAP
A1  - Pfaff, Raphael
A1  - Melcher, Karin
A1  - Franzen, Julian
T1  - Rare event simulation to optimise maintenance intervals of safety critical redundant subsystems
T2  - Proceedings of the European Conference of the PHM Society
Y1  - 2018
VL  - 4
IS  - 1
SP  - 1
EP  - 6
ER  -