@incollection{KallweitGottschalkWalenta2016, author = {Kallweit, Stephan and Gottschalk, Michael and Walenta, Robert}, title = {ROS based safety concept for collaborative robots in industrial applications}, series = {Advances in robot design and intelligent control : proceedings of the 24th International Conference on Robotics in Alpe-Adria-Danube Region (RAAD). (Advances in intelligent systems and computing ; 371)}, booktitle = {Advances in robot design and intelligent control : proceedings of the 24th International Conference on Robotics in Alpe-Adria-Danube Region (RAAD). (Advances in intelligent systems and computing ; 371)}, publisher = {Springer}, address = {Cham}, organization = {International Conference on Robotics in Alpe-Adria-Danube Region <24, 2015, Bucharest>}, isbn = {978-3-319-21289-0 (Print) ; 978-3-319-21290-6 (E-Book)}, doi = {10.1007/978-3-319-21290-6_3}, pages = {27 -- 35}, year = {2016}, abstract = {The production and assembly of customized products increases the demand for flexible automation systems. One approach is to remove the safety fences that separate human and industrial robot to combine their skills. This collaboration possesses a certain risk for the human co-worker, leading to numerous safety concepts to protect him. The human needs to be monitored and tracked by a safety system using different sensors. The proposed system consists of a RGBD camera for surveillance of the common working area, an array of optical distance sensors to compensate shadowing effects of the RGBD camera and a laser range finder to detect the co-worker when approaching the work cell. The software for collision detection, path planning, robot control and predicting the behaviour of the co-worker is based on the Robot Operating System (ROS). A first prototype of the work cell shows that with advanced algorithms from the field of mobile robotics a very flexible safety concept can be realized: the robot not simply stops its movement when detecting a collision, but plans and executes an alternative path around the obstacle.}, language = {en} } @article{FateriGebhardt2015, author = {Fateri, Miranda and Gebhardt, Andreas}, title = {Additive manufactured mechanical disentanglement lock}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {12}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, publisher = {Fachhochschule Aachen}, address = {Aachen}, issn = {1614-0923}, url = {http://nbn-resolving.de/urn:nbn:de:0009-2-42147}, year = {2015}, language = {en} } @inproceedings{GrossmannGabrielliHerdrichetal.2015, author = {Großmann, Agnes and Gabrielli, Roland Antonius and Herdrich, Georg and Fasoulas, Stefanos and Schnauffer, Peter and Middendorf, Peter and Fateri, Miranda and Gebhardt, Andreas}, title = {Overview of the MultiRob 3D Lunar Industrial Development Project}, series = {Conference Contribution for the 30th ISTS, Kobe, Japan, 04.07.-10.07.2015}, booktitle = {Conference Contribution for the 30th ISTS, Kobe, Japan, 04.07.-10.07.2015}, pages = {8 S.}, year = {2015}, language = {en} } @inproceedings{FerreinKallweitScholletal.2015, author = {Ferrein, Alexander and Kallweit, Stephan and Scholl, Ingrid and Reichert, Walter}, title = {Learning to Program Mobile Robots in the ROS Summer School Series}, series = {Proceedings 6th International Conference on Robotics in Education (RiE 15)}, booktitle = {Proceedings 6th International Conference on Robotics in Education (RiE 15)}, pages = {6 S.}, year = {2015}, abstract = {The main objective of our ROS Summer School series is to introduce MA level students to program mobile robots with the Robot Operating System (ROS). ROS is a robot middleware that is used my many research institutions world-wide. Therefore, many state-of-the-art algorithms of mobile robotics are available in ROS and can be deployed very easily. As a basic robot platform we deploy a 1/10 RC cart that is wquipped with an Arduino micro-controller to control the servo motors, and an embedded PC that runs ROS. In two weeks, participants get to learn the basics of mobile robotics hands-on. We describe our teaching concepts and our curriculum and report on the learning success of our students.}, language = {en} } @inproceedings{GregorioFatigatiKallweit2015, author = {Gregorio, Fabrizio de and Fatigati, Giovanni and Kallweit, Stephan}, title = {Tiltrotor airframe flow field characterization by SPIV}, series = {11th International Symposium on Partivle Image Velocimetry - PIV15 , Santa Barbara, California, Sept 14-16, 2015}, booktitle = {11th International Symposium on Partivle Image Velocimetry - PIV15 , Santa Barbara, California, Sept 14-16, 2015}, pages = {15 S.}, year = {2015}, language = {en} } @inproceedings{AlhwarinFerreinGebhardtetal.2015, author = {Alhwarin, Faraj and Ferrein, Alexander and Gebhardt, Andreas and Kallweit, Stephan and Scholl, Ingrid and Tedjasukmana, Osmond Sanjaya}, title = {Improving additive manufacturing by image processing and robotic milling}, series = {2015 IEEE International Conference on Automation Science and Engineering (CASE), Aug 24-28, 2015 Gothenburg, Sweden}, booktitle = {2015 IEEE International Conference on Automation Science and Engineering (CASE), Aug 24-28, 2015 Gothenburg, Sweden}, doi = {10.1109/CoASE.2015.7294217}, pages = {924 -- 929}, year = {2015}, language = {en} } @article{KesslerBalcGebhardtetal.2015, author = {Kessler, Julia and Balc, Nicolae and Gebhardt, Andreas and Abbas, Karim}, title = {Basic Research on Lattice Structures Focused on the Tensile Strength}, series = {Applied Mechanics and Materials}, volume = {Vol. 808}, journal = {Applied Mechanics and Materials}, publisher = {Trans Tech Publications}, address = {B{\"a}ch}, issn = {1662-7482}, doi = {10.4028/www.scientific.net/AMM.808.193}, pages = {193 -- 198}, year = {2015}, language = {en} } @inproceedings{FateriGebhardtGabriellietal.2015, author = {Fateri, Miranda and Gebhardt, Andreas and Gabrielli, Roland Antonius and Herdrich, Georg and Fasoulas, Stefanos and Großmann, Agnes and Schnauffer, Peter and Middendorf, Peter}, title = {Additive Manufacturing of Lunar Regolith for Extra-terrestrial Industry Plant}, series = {International Symposium on Space Technology and Science (ICTS). July 2015, Kobe, Japan}, booktitle = {International Symposium on Space Technology and Science (ICTS). July 2015, Kobe, Japan}, pages = {5 S.}, year = {2015}, language = {en} } @inproceedings{GabrielliMathiesGrossmannetal.2015, author = {Gabrielli, Roland Antonius and Mathies, Johannes and Großmann, Agnes and Herdrich, Georg and Fasoulas, Stefanos and Middendorf, Peter and Fateri, Miranda and Gebhardt, Andreas}, title = {Space Propulsion Considerations for a Lunar Take Off Industry Based on Regolith}, series = {International Symposium on Space Technology and Science (ISTS). July 2015, Kobe, Japan}, booktitle = {International Symposium on Space Technology and Science (ISTS). July 2015, Kobe, Japan}, year = {2015}, language = {en} } @inproceedings{FateriGebhardtRenftle2015, author = {Fateri, Miranda and Gebhardt, Andreas and Renftle, Georg}, title = {Additive Manufacturing of Drainage Segments for Cooling System of Crucibles Melting Furnaces}, series = {International Conference and Expo on Advanced Ceramics and Composites, (ICACC). January 2015, Florida, USA}, booktitle = {International Conference and Expo on Advanced Ceramics and Composites, (ICACC). January 2015, Florida, USA}, pages = {9 S.}, year = {2015}, abstract = {The cooling process in induction based crucible melting furnaces for Industrial applications is one of the important and challenging factors in production and safety engineering. Accordingly, proper implementation of the cooling system of the furnace using optimum cooling guides and fail-safe features are critical in order to improve the safety of the process. Regarding this, manufacturing of porous material with high electrical isolation for the drainage segments of the cooling channels is examined in this study. Consequently, various geometries with different porosities using glass and ceramic powder are fabricated using Selective Laser Sintering (SLS) process. The manufactured parts are examined in a prototype furnace testing and the feasibility of the SLS manufacturing of parts for this application is discussed.}, language = {en} } @inproceedings{NakagawaMichauxKallweitetal.2015, author = {Nakagawa, Masaki and Michaux, Frank and Kallweit, Stephan and Maeda, Kazuhiro}, title = {Unsteady flow measurements in the wake behind a wind-tunnel car model by using high-speed planar PIV}, series = {11TH International Symposium on Particle Image Velocimetry - PIV15 Santa Barbara, California, September 14-16, 2015}, booktitle = {11TH International Symposium on Particle Image Velocimetry - PIV15 Santa Barbara, California, September 14-16, 2015}, pages = {21 S.}, year = {2015}, abstract = {This study investigates unsteady characteristics of the wake behind a 28\%-scale car model in a wind tunnel using highspeed planar particle image velocimetry (PIV). The car model is based on a hatchback passenger car that is known to have relatively high fluctuations in its aerodynamic loads. This study primarily focuses on the lateral motion of the flow on the horizontal plane to determine the effect of the flow motion on the straight-line stability and the initial steering response of the actual car on a track. This paper first compares the flow fields in the wake behind the above mentioned model obtained using conventional and high-speed planar PIV, with sampling frequencies of 8 Hz and 1 kHz, respectively. Large asymmetrically coherent flow structures, which fluctuate at frequencies below 2 Hz, are observed in the results of highspeed PIV measurements, whereas conventional PIV is unable to capture these features of the flow owing to aliasing. This flow pattern with a laterally swaying motion is represented by opposite signs of cross-correlation coefficients of streamwise velocity fluctuations for the two sides of the car model. Effects of two aerodynamic devices that are known to reduce the fluctuation levels of the aerodynamic loads are then extensively investigated. The correlation analyses reveal that these devices indeed reduce the fluctuation levels of the flow and the correlation values around the rear combination-lamp, but it is found that the effects of these devices are different around the c-pillar.}, language = {en} } @inproceedings{KilicRaatschenAstanehAsletal.2015, author = {Kilic, S. A. and Raatschen, Hans-J{\"u}rgen and Astaneh-Asl, A. and Apaydin, N. M.}, title = {Finite element modeling of the Fatih Sultan Mehmet Suspension Bridge}, series = {Multi-Span Large Bridges - Proceedings of the International Conference on Multi-Span Large Bridges}, booktitle = {Multi-Span Large Bridges - Proceedings of the International Conference on Multi-Span Large Bridges}, publisher = {CRC Press}, address = {Leiden}, isbn = {9781138027572}, pages = {1169 -- 1173}, year = {2015}, language = {en} } @inproceedings{Wollert2015, author = {Wollert, J{\"o}rg}, title = {Wireless systems for machinery safety : Requirements and solutions for wireless real time systems}, series = {16th International Conference on Research and Education in Mechatronics (REM), 2015}, booktitle = {16th International Conference on Research and Education in Mechatronics (REM), 2015}, isbn = {978-3-945728-01-7}, doi = {10.1109/REM.2015.7380377}, pages = {88 -- 91}, year = {2015}, language = {en} } @inproceedings{NakagawaKallweitMichauxetal.2016, author = {Nakagawa, Masaki and Kallweit, Stephan and Michaux, Frank and Hojo, Teppei}, title = {Typical Velocity Fields and Vortical Structures around a Formula One Car, based on Experimental Investigations using Particle Image Velocimetry}, series = {SAE International Journal of Passenger Cars - Mechanical Systems}, booktitle = {SAE International Journal of Passenger Cars - Mechanical Systems}, issn = {1946-4002}, doi = {10.4271/2016-01-1611}, pages = {18 S.}, year = {2016}, language = {en} } @book{GebhardtHoetter2016, author = {Gebhardt, Andreas and H{\"o}tter, Jan-Steffen}, title = {Additive manufacturing : 3D printing for prototyping and manufacturing}, publisher = {Hanser Publishers}, address = {Munich}, isbn = {978-1-56990-582-1 ; 978-1-56990-583-8}, pages = {591 S.}, year = {2016}, language = {en} } @article{KosterScheidweilerTieves2016, author = {Koster, Arie and Scheidweiler, Robert and Tieves, Martin}, title = {A flow based pruning scheme for enumerative equitable coloring algorithms}, series = {A flow based pruning scheme for enumerative equitable coloring algorithms}, journal = {A flow based pruning scheme for enumerative equitable coloring algorithms}, doi = {10.48550/arXiv.1607.08754}, pages = {1 -- 30}, year = {2016}, abstract = {An equitable graph coloring is a proper vertex coloring of a graph G where the sizes of the color classes differ by at most one. The equitable chromatic number is the smallest number k such that G admits such equitable k-coloring. We focus on enumerative algorithms for the computation of the equitable coloring number and propose a general scheme to derive pruning rules for them: We show how the extendability of a partial coloring into an equitable coloring can be modeled via network flows. Thus, we obtain pruning rules which can be checked via flow algorithms. Computational experiments show that the search tree of enumerative algorithms can be significantly reduced in size by these rules and, in most instances, such naive approach even yields a faster algorithm. Moreover, the stability, i.e., the number of solved instances within a given time limit, is greatly improved. Since the execution of flow algorithms at each node of a search tree is time consuming, we derive arithmetic pruning rules (generalized Hall-conditions) from the network model. Adding these rules to an enumerative algorithm yields an even larger runtime improvement.}, language = {en} } @article{BeckenbachScheidweiler2016, author = {Beckenbach, Isabel and Scheidweiler, Robert}, title = {Perfect ƒ-Matchings and ƒ-Factors in Hypergraphs - A Combinatorial Approach}, series = {Discrete Mathematics}, volume = {240}, journal = {Discrete Mathematics}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2192-7782}, doi = {10.1016/j.disc.2017.05.005}, pages = {2499 -- 2506}, year = {2016}, abstract = {We prove characterizations of the existence of perfect ƒ-matchings in uniform mengerian and perfect hypergraphs. Moreover, we investigate the ƒ-factor problem in balanced hypergraphs. For uniform balanced hypergraphs we prove two existence theorems with purely combinatorial arguments, whereas for non-uniform balanced hypergraphs we show that the ƒ-factor problem is NP-hard.}, language = {en} } @article{ScheidweilerTriesch2016, author = {Scheidweiler, Robert and Triesch, Eberhard}, title = {A note on the duality between matchings and vertex covers in balanced hypergraphs}, series = {Journal of Combinatorial Optimization}, volume = {32}, journal = {Journal of Combinatorial Optimization}, number = {2}, publisher = {Springer}, address = {Berlin}, issn = {1573-2886}, doi = {10.1007/s10878-015-9887-5}, pages = {639 -- 644}, year = {2016}, abstract = {We present a new Min-Max theorem for an optimization problem closely connected to matchings and vertex covers in balanced hypergraphs. The result generalizes Kőnig's Theorem (Berge and Las Vergnas in Ann N Y Acad Sci 175:32-40, 1970; Fulkerson et al. in Math Progr Study 1:120-132, 1974) and Hall's Theorem (Conforti et al. in Combinatorica 16:325-329, 1996) for balanced hypergraphs.}, language = {en} } @article{KilicRaatschenKoerfgenetal.2017, author = {Kilic, S. A. and Raatschen, Hans-J{\"u}rgen and K{\"o}rfgen, B. and Apaydin, N. M. and Astaneh-Asl, A.}, title = {FE Model of the Fatih Sultan Mehmet Suspension Bridge Using Thin Shell Finite Elements}, series = {Arabian Journal for Science and Engineering}, volume = {42}, journal = {Arabian Journal for Science and Engineering}, number = {3}, publisher = {Springer Nature}, issn = {2191-4281}, doi = {10.1007/s13369-016-2316-y}, pages = {1103 -- 1116}, year = {2017}, abstract = {This paper presents the results of an eigenvalue analysis of the Fatih Sultan Mehmet Bridge. A high-resolution finite element model was created directly from the available design documents. All physical properties of the structural components were included in detail, so no calibration to the measured data was necessary. The deck and towers were modeled with shell elements. A nonlinear static analysis was performed before the eigenvalue calculation. The calculated natural frequencies and corresponding mode shapes showed good agreement with the available measured ambient vibration data. The calculation of the effective modal mass showed that nine modes had single contributions higher than 5 \% of the total mass. They were in a frequency range up to 1.2 Hz. The comparison of the results for the torsional modes especially demonstrated the advantage of using thin shell finite elements over the beam modeling approach.}, language = {en} } @article{RieperGebhardtStucker2016, author = {Rieper, Harald and Gebhardt, Andreas and Stucker, Brent}, title = {Selective Laser Melting of the Eutectic Silver-Copper Alloy Ag 28 wt \% Cu}, series = {RTejournal - Forum f{\"u}r Rapid Technologie}, volume = {13}, journal = {RTejournal - Forum f{\"u}r Rapid Technologie}, issn = {1614-0923}, url = {http://nbn-resolving.de/nbn:de:0009-2-44141}, year = {2016}, abstract = {The aim of this work was to perform a detailed investigation of the use of Selective Laser Melting (SLM) technology to process eutectic silver-copper alloy Ag 28 wt. \% Cu (also called AgCu28). The processing occurred with a Realizer SLM 50 desktop machine. The powder analysis (SEM-topography, EDX, particle distribution) was reported as well as the absorption rates for the near-infrared (NIR) spectrum. Microscope imaging showed the surface topography of the manufactured parts. Furthermore, microsections were conducted for the analysis of porosity. The Design of Experiments approach used the response surface method in order to model the statistical relationship between laser power, spot distance and pulse time.}, language = {en} } @article{HaagZontarSchleupenetal.2014, author = {Haag, S. and Zontar, D. and Schleupen, Josef and M{\"u}ller, T. and Brecher, C.}, title = {Chain of refined perception in self-optimizing assembly of micro-optical systems}, series = {Journal of sensors and sensor systems}, volume = {3}, journal = {Journal of sensors and sensor systems}, number = {1}, publisher = {Copernicus Publ.}, address = {G{\"o}ttingen}, issn = {2194-878X}, doi = {10.5194/jsss-3-87-2014}, pages = {87 -- 95}, year = {2014}, abstract = {Today, the assembly of laser systems requires a large share of manual operations due to its complexity regarding the optimal alignment of optics. Although the feasibility of automated alignment of laser optics has been shown in research labs, the development effort for the automation of assembly does not meet economic requirements - especially for low-volume laser production. This paper presents a model-based and sensor-integrated assembly execution approach for flexible assembly cells consisting of a macro-positioner covering a large workspace and a compact micromanipulator with camera attached to the positioner. In order to make full use of available models from computer-aided design (CAD) and optical simulation, sensor systems at different levels of accuracy are used for matching perceived information with model data. This approach is named "chain of refined perception", and it allows for automated planning of complex assembly tasks along all major phases of assembly such as collision-free path planning, part feeding, and active and passive alignment. The focus of the paper is put on the in-process image-based metrology and information extraction used for identifying and calibrating local coordinate systems as well as the exploitation of that information for a part feeding process for micro-optics. Results will be presented regarding the processes of automated calibration of the robot camera as well as the local coordinate systems of part feeding area and robot base.}, language = {en} } @inproceedings{KesslerBalcGebhardt2016, author = {Kessler, Julia and Balc, Nicolae and Gebhardt, Andreas}, title = {Basic research on lattice structures focused on the strut shape and welding beads}, series = {Physics Procedia}, volume = {Vol. 83}, booktitle = {Physics Procedia}, issn = {1875-3884}, doi = {10.1016/j.phpro.2016.08.086}, pages = {833 -- 838}, year = {2016}, language = {en} } @inproceedings{KesslerBalcGebhardtetal.2017, author = {Kessler, Julia and Balc, Nicolae and Gebhardt, Andreas and Abbas, Karim}, title = {Basic research on lattice structures focused on the reliance of the cross sectional area and additional coatings}, series = {The 4th International Conference on Computing and Solutions in Manufacturing Engineering 2016 - CoSME'16}, booktitle = {The 4th International Conference on Computing and Solutions in Manufacturing Engineering 2016 - CoSME'16}, edition = {Vol. 94}, doi = {10.1051/matecconf/20179403008}, pages = {7 S.}, year = {2017}, language = {en} } @inproceedings{SchleupenEngemannBagherietal.2017, author = {Schleupen, Josef and Engemann, Heiko and Bagheri, Mohsen and Kallweit, Stephan and Dahmann, Peter}, title = {Developing a climbing maintenance robot for tower and rotor blade service of wind turbines}, series = {Advances in Robot Design and Intelligent Control : Proceedings of the 25th Conference on Robotics in Alpe-Adria-Danube Region (RAAD16)}, booktitle = {Advances in Robot Design and Intelligent Control : Proceedings of the 25th Conference on Robotics in Alpe-Adria-Danube Region (RAAD16)}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-49058-8}, doi = {10.1007/978-3-319-49058-8_34}, pages = {310 -- 319}, year = {2017}, language = {en} } @inproceedings{ThurnGebhardt2017, author = {Thurn, Laura and Gebhardt, Andreas}, title = {Arousing Enthusiasm for STEM: Teaching 3D Printing Technology}, series = {Conference Proceedings: New Perspectives in Science Education}, booktitle = {Conference Proceedings: New Perspectives in Science Education}, publisher = {liberiauniversitaria.it}, address = {Padua}, isbn = {978-88-6292-847-2}, pages = {87 -- 92}, year = {2017}, language = {en} } @inproceedings{EngemannWiesenKallweitetal.2018, author = {Engemann, Heiko and Wiesen, Patrick and Kallweit, Stephan and Deshpande, Harshavardhan and Schleupen, Josef}, title = {Autonomous mobile manipulation using ROS}, series = {Advances in Service and Industrial Robotics}, booktitle = {Advances in Service and Industrial Robotics}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-61276-8}, doi = {10.1007/978-3-319-61276-8_43}, pages = {389 -- 401}, year = {2018}, language = {en} } @inproceedings{KleineKallweitMichauxetal.2016, author = {Kleine, Harald and Kallweit, Stephan and Michaux, Frank and Havermann, Marc and Olivier, Herbert}, title = {PIV Measurement of Shock Wave Diffraction}, series = {18th International Symposium on Applications of Laser Techniques to Fluid Mechanics, 2016, Lissabon}, booktitle = {18th International Symposium on Applications of Laser Techniques to Fluid Mechanics, 2016, Lissabon}, pages = {1 -- 14}, year = {2016}, language = {en} } @inproceedings{SchleupenEngemannBagherietal.2016, author = {Schleupen, Josef and Engemann, Heiko and Bagheri, Mohsen and Kallweit, Stephan}, title = {The potential of SMART climbing robot combined with a weatherproof cabin for rotor blade maintenance}, series = {17th European Conference on Composite Materials - ECCM, Munich, Germany}, booktitle = {17th European Conference on Composite Materials - ECCM, Munich, Germany}, pages = {1 -- 8}, year = {2016}, language = {en} } @inproceedings{PfaffSchmidtEnning2017, author = {Pfaff, Raphael and Schmidt, B. D. and Enning, Manfred}, title = {Towards inclusion of the freight rail system in the industrial internet of things - Wagon 4.0}, series = {Stephenson Conference, London, March 2017}, booktitle = {Stephenson Conference, London, March 2017}, pages = {1 -- 10}, year = {2017}, language = {en} } @inproceedings{ThurnBalcGebhardtetal.2017, author = {Thurn, Laura and Balc, Nicolae and Gebhardt, Andreas and Kessler, Julia}, title = {Education packed in technology to promote innovations: Teaching Additive Manufacturing based on a rolling Lab}, series = {Modern Technologies in Manufacturing (MTeM 2017 - AMaTUC)}, booktitle = {Modern Technologies in Manufacturing (MTeM 2017 - AMaTUC)}, issn = {2261-236X}, doi = {10.1051/matecconf/201713702013}, pages = {6 Seiten}, year = {2017}, language = {en} } @inproceedings{PfaffMoshiriReichetal.2017, author = {Pfaff, Raphael and Moshiri, Amir and Reich, Alexander and G{\"a}bel, Markus}, title = {Modelling of the effect of sanding on the wheel-rail adhesion area}, series = {First International Conference on Rail Transportation}, booktitle = {First International Conference on Rail Transportation}, pages = {1 -- 7}, year = {2017}, language = {en} } @inproceedings{ShahidiPfaffEnning2017, author = {Shahidi, Parham and Pfaff, Raphael and Enning, Manfred}, title = {The connected wagon - a concept for the integration of vehicle side sensors and actors with cyber physical representation for condition based maintenance}, series = {First International Conference on Rail Transportation}, booktitle = {First International Conference on Rail Transportation}, pages = {1 -- 8}, year = {2017}, language = {en} } @inproceedings{PfaffShahidiEnning2017, author = {Pfaff, Raphael and Shahidi, Parham and Enning, Manfred}, title = {Connected freight rail rolling stock: a modular approach integrating sensors, actors and cyber physical systems for operational advantages and condition based maintenance}, series = {Asia-Pacific Conference of the Prognostics and Health Management Society}, booktitle = {Asia-Pacific Conference of the Prognostics and Health Management Society}, pages = {1 -- 7}, year = {2017}, language = {en} } @inproceedings{Pfaff2017, author = {Pfaff, Raphael}, title = {Analysis of Big Data Streams to obtain Braking Reliability Information for Train Protection systems}, series = {Asia-Pacific Conference of the Prognostics and Health Management Society}, booktitle = {Asia-Pacific Conference of the Prognostics and Health Management Society}, pages = {1 -- 7}, year = {2017}, language = {en} } @article{MichauxMatternKallweit2018, author = {Michaux, F. and Mattern, P. and Kallweit, Stephan}, title = {RoboPIV: how robotics enable PIV on a large industrial scale}, series = {Measurement Science and Technology}, volume = {29}, journal = {Measurement Science and Technology}, number = {7}, publisher = {IOP}, address = {Bristol}, issn = {1361-6501}, doi = {10.1088/1361-6501/aab5c1}, pages = {074009}, year = {2018}, abstract = {This work demonstrates how the interaction between particle image velocimetry (PIV) and robotics can massively increase measurement efficiency. The interdisciplinary approach is shown using the complex example of an automated, large scale, industrial environment: a typical automotive wind tunnel application. Both the high degree of flexibility in choosing the measurement region and the complete automation of stereo PIV measurements are presented. The setup consists of a combination of three robots, individually used as a 6D traversing unit for the laser illumination system as well as for each of the two cameras. Synchronised movements in the same reference frame are realised through a master-slave setup with a single interface to the user. By integrating the interface into the standard wind tunnel management system, a single measurement plane or a predefined sequence of several planes can be requested through a single trigger event, providing the resulting vector fields within minutes. In this paper, a brief overview on the demands of large scale industrial PIV and the existing solutions is given. Afterwards, the concept of RoboPIV is introduced as a new approach. In a first step, the usability of a selection of commercially available robot arms is analysed. The challenges of pose uncertainty and importance of absolute accuracy are demonstrated through comparative measurements, explaining the individual pros and cons of the analysed systems. Subsequently, the advantage of integrating RoboPIV directly into the existing wind tunnel management system is shown on basis of a typical measurement sequence. In a final step, a practical measurement procedure, including post-processing, is given by using real data and results. Ultimately, the benefits of high automation are demonstrated, leading to a drastic reduction in necessary measurement time compared to non-automated systems, thus massively increasing the efficiency of PIV measurements.}, language = {en} } @article{KunkelGebhardtMpofuetal.2018, author = {Kunkel, Maximilian Hugo and Gebhardt, Andreas and Mpofu, Khumbaulani and Kallweit, Stephan}, title = {Statistical assessment of mechanical properties of selective laser melted specimens of stainless steel}, series = {The International Journal of Advanced Manufacturing Technology}, volume = {98}, journal = {The International Journal of Advanced Manufacturing Technology}, number = {5-8}, publisher = {Springer}, address = {London}, issn = {0268-3768}, doi = {10.1007/s00170-018-2040-8}, pages = {1409 -- 1431}, year = {2018}, abstract = {The rail business is challenged by long product life cycles and a broad spectrum of assembly groups and single parts. When spare part obsolescence occurs, quick solutions are needed. A reproduction of obsolete parts is often connected to long waiting times and minimum lot quantities that need to be purchased and stored. Spare part storage is therefore challenged by growing stocks, bound capital and issues of part ageing. A possible solution could be a virtual storage of spare parts which will be 3D printed through additive manufacturing technologies in case of sudden demand. As mechanical properties of additive manufactured parts are neither guaranteed by machine manufacturers nor by service providers, the utilization of this relatively young technology is impeded and research is required to address these issues. This paper presents an examination of mechanical properties of specimens manufactured from stainless steel through the selective laser melting (SLM) process. The specimens were produced in multiple batches. This paper interrogates the question if the test results follow a normal distribution pattern and if mechanical property predictions can be made. The results will be put opposite existing threshold values provided as the industrial standard. Furthermore, probability predictions will be made in order to examine the potential of the SLM process to maintain state-of-the-art mechanical property requirements.}, language = {en} } @inproceedings{FerreinSchifferKallweit2018, author = {Ferrein, Alexander and Schiffer, Stefan and Kallweit, Stephan}, title = {The ROSIN Education Concept - Fostering ROS Industrial-Related Robotics Education in Europe}, series = {ROBOT 2017: Third Iberian Robotics Conference}, booktitle = {ROBOT 2017: Third Iberian Robotics Conference}, publisher = {Springer}, address = {Cham}, isbn = {978-3-319-70836-2}, doi = {10.1007/978-3-319-70836-2_31}, pages = {370 -- 381}, year = {2018}, language = {en} } @book{GebhardtKesslerThurn2019, author = {Gebhardt, Andreas and Kessler, Julia and Thurn, Laura}, title = {3D printing : understanding additive manufacturing}, edition = {2. Auflage}, publisher = {Hanser}, address = {M{\"u}nchen}, isbn = {978-1-56990-702-3}, pages = {XVI, 204 Seiten}, year = {2019}, language = {en} } @inproceedings{FateriGebhardtRenftle2015, author = {Fateri, Miranda and Gebhardt, Andreas and Renftle, Georg}, title = {Additive manufacturing of drainage segments for cooling system of crucible melting furnaces}, series = {Advanced Processing and Manufacturing Technologies for Structural and Multifunctional Materials II, International Symposium on Advanced Processing and Manufacturing Technologies for Structural and Multifunctional Materials, ICACC 15, 39th International Conference on Advanced Ceramics and Composites, Daytona Beach, FL, US, Jan 25-30, 2015}, booktitle = {Advanced Processing and Manufacturing Technologies for Structural and Multifunctional Materials II, International Symposium on Advanced Processing and Manufacturing Technologies for Structural and Multifunctional Materials, ICACC 15, 39th International Conference on Advanced Ceramics and Composites, Daytona Beach, FL, US, Jan 25-30, 2015}, publisher = {Wiley}, address = {Hoboken}, issn = {0196-6219}, doi = {10.1002/9781119211662.ch14}, pages = {123 -- 131}, year = {2015}, language = {en} } @inproceedings{GaoBabilonPfaffetal.2018, author = {Gao, H. and Babilon, Katharina and Pfaff, Raphael and Gan, F. and Reich, A.}, title = {Model of wheel-rail contact for sanding and adhesion enhancement}, series = {Proceedings of the 11th International Conference on Contact Mechanics and Wear of Rail/wheel Systems, CM 2018}, booktitle = {Proceedings of the 11th International Conference on Contact Mechanics and Wear of Rail/wheel Systems, CM 2018}, isbn = {978-946186963-0}, pages = {314 -- 321}, year = {2018}, language = {en} } @article{FranzenPindersPfaffetal.2018, author = {Franzen, Julius and Pinders, Erik and Pfaff, Raphael and Enning, Manfred}, title = {RailCrowd's virtual fleets: Make most of your asset data}, series = {Deine Bahn}, journal = {Deine Bahn}, number = {9}, publisher = {Bahn-Fachverlag}, address = {Berlin}, issn = {0948-7263}, pages = {11 -- 13}, year = {2018}, abstract = {For smaller railway operators or those with a diverse fleet, it can be difficult to collect sufficient data to improve maintenance programs. At the same time, new rules such as entity in charge of maintenance - ECM - regulations impose an additional workload by requiring a dedicated maintenance management system and specific reports. The RailCrowd platform sets out to facilitate compliance with ECM and similar regulations while at the same time pooling anonymised fleet data across operators to form virtual fleets, providing greater data insights.}, language = {en} } @inproceedings{PfaffMelcherFranzen2018, author = {Pfaff, Raphael and Melcher, Karin and Franzen, Julian}, title = {Rare event simulation to optimise maintenance intervals of safety critical redundant subsystems}, series = {Proceedings of the European Conference of the PHM Society}, volume = {4}, booktitle = {Proceedings of the European Conference of the PHM Society}, number = {1}, pages = {1 -- 6}, year = {2018}, language = {en} } @inproceedings{ThurnGebhardt2018, author = {Thurn, Laura and Gebhardt, Andreas}, title = {Strategy of Education on Materials for Students}, series = {Conference Proceedings: „New Perspectives in Science Education"}, booktitle = {Conference Proceedings: „New Perspectives in Science Education"}, address = {Florence, Italy}, isbn = {978-88-6292-976-9}, pages = {156 -- 161}, year = {2018}, language = {en} } @inproceedings{BueckingPfaffDirksmeier2018, author = {B{\"u}cking, Henrik and Pfaff, Raphael and Dirksmeier, Roger}, title = {Sensor positioning and thermal model for condition monitoring of pressure gas reservoirs in vehicles}, series = {Proceedings of the Fourth European Conference of the Prognostics and Health Management Society, Utrecht, Netherlands, 2018}, booktitle = {Proceedings of the Fourth European Conference of the Prognostics and Health Management Society, Utrecht, Netherlands, 2018}, pages = {5 Seiten}, year = {2018}, language = {en} } @inproceedings{WiesenEngemannLimpertetal.2018, author = {Wiesen, Patrick and Engemann, Heiko and Limpert, Nicolas and Kallweit, Stephan}, title = {Learning by Doing - Mobile Robotics in the FH Aachen ROS Summer School}, series = {European Robotics Forum 2018, TRROS18 Workshop}, booktitle = {European Robotics Forum 2018, TRROS18 Workshop}, pages = {47 -- 58}, year = {2018}, language = {en} } @inproceedings{RieperGebhardtStucker2016, author = {Rieper, Harald and Gebhardt, Andreas and Stucker, Brent}, title = {Process parameters for Selective Laser Melting of AgCu7}, series = {DDMC, Fraunhofer Direct Digital Manufacturing Conference, 3}, booktitle = {DDMC, Fraunhofer Direct Digital Manufacturing Conference, 3}, publisher = {Fraunhofer-Verlag}, address = {Stuttgart}, isbn = {978-3-8396-1001-5}, pages = {171 -- 176}, year = {2016}, language = {en} } @incollection{FranzenSteckenPfaffetal.2019, author = {Franzen, Julian and Stecken, Jannis and Pfaff, Raphael and Kuhlenk{\"o}tter, Bernd}, title = {Using the Digital Shadow for a Prescriptive Optimization of Maintenance and Operation : The Locomotive in the Context of the Cyber-Physical System}, series = {Advances in Production, Logistics and Traffic}, booktitle = {Advances in Production, Logistics and Traffic}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-13535-5}, doi = {10.1007/978-3-030-13535-5_19}, pages = {265 -- 276}, year = {2019}, abstract = {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.}, language = {en} } @article{BucurLazarescuPopetal.2019, author = {Bucur, Alexandru and Lazarescu, Lucian and Pop, Grigore Marian and Achimas, Gheorghe and Gebhardt, Andreas}, title = {Tribological performance of biodegradable lubricants under different surface roughness of tools}, series = {Academic Journal of Manufacturing Engineering}, volume = {17}, journal = {Academic Journal of Manufacturing Engineering}, number = {1}, issn = {1583-7904}, pages = {172 -- 178}, year = {2019}, language = {en} } @article{PancContiuBocanetetal.2019, author = {Panc, Nicolae and Contiu, Glad and Bocanet, Vlad and Thurn, Laura and Sabau, Emilia}, title = {The influence of cutting technology on surface wear hardness}, series = {Academic Journal of Manufacturing Engineering}, volume = {17}, journal = {Academic Journal of Manufacturing Engineering}, number = {3}, issn = {1583-7904}, pages = {205 -- 210}, year = {2019}, language = {en} } @inproceedings{LuftGebhardtBalc2019, author = {Luft, Angela and Gebhardt, Andreas and Balc, Nicolae}, title = {Challenges of additive manufacturing in production systems}, series = {Modern technologies in manufacturing (MTeM 2019)}, volume = {299}, booktitle = {Modern technologies in manufacturing (MTeM 2019)}, number = {Article 01003}, doi = {10.1051/matecconf/201929901003}, pages = {6 Seiten}, year = {2019}, language = {en} }