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2013 IFAC Bio-Robotics Conference, IFAC BioRobotics 2013

作者： Radojicic, J. Surdilovic, D. Krüger, J. Fraunhofer Institute for Production Systems and Design Technology Pascalstr 8-9 10587 Berlin Germany Institute for Machine Tools Factory Management Technical University Berlin Pascalstr. 8-9 10587 Berlin Germany

ISBN: (纸本)9783902823304

The paper presents an efficient approach for the modelling of wire robots kinematic and dynamics considering the effects of structural elasticity. Using the simulation and animation system several potential applications in agriculture have been simulated and analysed. The paper discusses possible robot configurations, system dynamic constraints and limits, as well as reachable performance for typical large-span wire robot applications in agriculture.

关键词： Agriculture

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Optimization of Mechanical Loaded Lattice Structures by Orientating their Struts Along the Flux of Force

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Procedia CIRP 2013年 12卷 175-180页

作者： G. Reinhart S. Teufelhart Fraunhofer Institute for Machine Tools and Forming Technologies (IWU) Project Group for Resource-Efficient Mechatronic Processing Machines (RMV) Beim Glaspalast 5 86153 Augsburg Germany

Additive Layer Manufacturing (ALM) processes like Selective Laser Melting (SLM) show a great potential for the fabrication of lightweight components due to their high geometric flexibility. Thereby, especially mesoscopic approaches feature some very advantageous properties like high stiffness and strength combined with low masses. A periodical build-up of these structures is not ideal, because of the appearance of unfavorable load cases like bending or shearing inside the struts. Rather, only push and pull forces should appear. To reach this state, the course of the structure has to be adapted in order to avoid bending forces or at least to minimize them. This can be achieved by the orientation of the single struts along the flux of force inside the available design space. For this purpose, a procedure has been developed, which makes it possible to adapt the course of a structure to the flux of force inside a given part.

关键词： Structure Design method Algorithm

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Tailored microfluidic chips for biotechnology 13

Tailored microfluidic chips for biotechnology

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13th International Conference of the European Society for Precision Engineering and Nanotechnology, EUSPEN 2013

作者： Uhlmann, E. Mahr, F. Hein, C. Herms, K. Oberschmidt, D. Fraunhofer Institute for Production Systems and Design Technology Pascalstr. 8-9 10587 Berlin Germany Institute for Machine Tools and Factory Management Technische Universität Berlin Pascalstr. 8-9 10587 Berlin Germany

ISBN: (纸本)9780956679024

This work presents new approaches for the manufacturing of tailored microfluidic bioreactor chips, adapted to the requirements of innovative methods and to the evolutionary state of the process design. Taking a microfluidic bioreactor chip for cell-free protein synthesis as an example, this study describes in detail the advantages and disadvantages of different manufacturing procedures with regard to cost efficiency and process-related functionality. In this connection, different production processes for the manufacturing of prototypes, small and medium batches and for the manufacturing of mass-products are compared. Moreover, processing parameters were optimized in terms of the technological relevant characteristics such as surface roughness, planarity or structural resolution, were made. The qualitative assessment of the manufactured structures is made by manufacturing metrology and by an experimental study, based on the activity and yield of the cell-free expression of a fluorescent sample protein. As a result of this work, a detailed procedure for the manufacturing of microfluidic chips is recommended, along with an assessment of the impact on the performance of a biological system in the microfluidic devices.

关键词： Proteins

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Study of the Influences of Laser Parameters on Laser Assisted Machining Processes

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Procedia CIRP 2013年 8卷 170-175页

作者： Flaviana Tagliaferri Giacomo Leopardi Ulrich Semmler Michael Kuhl Biagio Palumbo Chemnitz University of Technology Institute for Machine Tools and Production Processes IWP Reichenhainer Str. 70 09126 Chemnitz Germany University of Naples Federico II Department of Industrial Engineering Piazzale V. Tecchio 80 80125 Naples Italy Fraunhofer Institute for Machine Tools and Forming Technology IWU Reichenhainer Str. 88 09126 Chemnitz Germany

Hybrid machining processes using additional energy sources such as laser assisted machining (LAM) have increased considerably during the last years. The benefits of LAM for reducing tool wear and cutting forces are well known, especially for superalloys. However, optimal machining results depend on both the laser parameters and the cutting process parameters. It is difficult to find optimal LAM settings due to the complexity of the influencing parameters and their mutual interactions. The aim of the paper is to characterize the laser heating process by detecting how the individual LAM parameters influence working temperature, heat affected zone (HAZ) extension and laser track width. A reliable application requires a localized and controlled continuous heating of the material within the machining zone directly in front of the tool contact area. In this research statistical and technological knowledge is fully involved in the experimental activities. Therefore, a statistical study based on design of experiment (DoE) was carried out in order to investigate the effects of laser process parameters and their interactions. In practice, two-level fractional factorial design and analysis of variance (ANOVA) were applied. The following process parameters were examined: laser power, scanning speed, defocus (the distance between focal point and workpiece surface), temperature controlled by pyrometer, and surface roughness. Furthermore, a Finite Element (FE) model was developed based on experimental results in order to find out the optimal parameters for modeling the laser heating process. Future FE simulations of the laser assisted cutting processes will be carried out using this model of the moving laser source.

关键词： Laser assisted machining (LAM) Hybrid machining Design of experiment (DoE) Finite element method (FEM)

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Grain size effect of pre- and post-coating treated cemented carbides on PVD films' adhesion and mechanical properties

Grain size effect of pre- and post-coating treated cemented ...

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3rd International Conference of Engineering Against Failure, ICEAF 2013

作者： Bouzakis, Konstantinos-Dionysios Michailidis, Nikolaos Skordaris, Georgios Tsouknidas, Alexandros Makrimallakis, Stylianos Bouzakis, Emmanouil Laboratory for Machine Tools and Manufacturing Engineering Mechanical Engineering Department Aristotle University of Thessaloniki Greece Fraunhofer Project Center for Coatings in Manufacturing Centre for Research and Technology Hellas in Thessaloniki Fraunhofer Institute for Production Technology Aachen Germany Physical Metallurgy Laboratory Mechanical Engineering Department Aristotle University of Thessaloniki Greece

ISBN: (纸本)9789608810433

The grain size of coated cemented carbide tools may significantly affect the tool life by influencing either the coating adhesion to the substrate or the coating growth during deposition. In the present study three variously grained cemented carbides were coated with two different PVD films. Various pre- and post-treatments were applied, while their effect on the films' mechanical properties and adhesion was assessed by nanoindentations and inclined impact tests. The coatings deposited on ultrafine-grained substrates exhibited the highest mechanical properties overall. The research revealed elevated adhesive properties for the fine-grained substrate compared to the normal and ultra-finegrained one. The film adhesion of normal and fine-grained substrate can be further enhanced through micro-blasting. Post-treatments of the coatings were beneficial in all substrate cases, as brushing of the film surface removed droplets while at the same time inducing surface residual stresses at the coating resulting in a hardness increase.

关键词： Substrates

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Inverse Jet Electrochemical Machining for Functional Edge Shaping of Micro Bores

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Procedia CIRP 2013年 6卷 378-383页

作者： M. H.-Oschätzchen A. Martin G. Meichsner M. Kowalick H. Zeidler A. Schubert Chair Micromanufacturing Technology Faculty of Mechanical Engineering Chemnitz UT 09107 Chemnitz Germany Fraunhofer Institute for Machine Tools and Form ing Technology 09126 Chemnitz Germany

Micro bores are used for several high-precision applications, especially in hydraulic systems and fuel injectors. In this case the shape, particularly the edge rounding of the injection spray hole, has a significant influence on the atomization of fluids and therefore also on the combustion process [1] . From the present knowledge about the relationship between bore geometry and hydraulic properties requirements were derived which are not feasible applying conventional manufacturing techniques. In particular, it is currently not possible to adjust the flow coefficient and the cavitation point independent of each other. The flow coefficient significantly influences the atomization, while the cavitation is necessary to prevent coking of the injection holes. One way to decouple the flow coefficient and cavitation behavior is a functional edge rounding of the borehole. This cannot be represented by the previous ly applied hydroerosive rounding. Therefore inverse Jet Electrochemical Machining (inverse Jet -ECM) opens up new possibilities, as the erosion area is localised by the jet. In Jet -ECM the electrolyte is supplied through a nozzle at an average speed of about 20 m/s and adjusted perpendicular to the work piece surface. forming a free jet leads to a high localization of the current density resulting in a much localized machining area direct below the nozzle [2] . In this study an edge rounding of the micro nozzle bore is realized by an inversion of the Jet-ECM principle.

关键词： Electrochemical Machining ECM Jet -ECM Micro Bore fuel injection spray hole

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Multisensorial Self-learning Systems for Quality Monitoring of Carbon Fiber Composites in Aircraft Production

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Procedia CIRP 2013年 12卷 103-108页

作者： M. Kuhl T. Wiener M. Krauß University of Technology Chemnitz Reichenhainer Str. 70 09126 Chemnitz Germany Fraunhofer Institute for Machine Tools an Forming Technology Reichenhainer Str. 88 09126 Chemnitz Germany InfraTec GmbH Gostrizer Str. 61-63 01217 Dresden Germany

Currently in the aerospace industry is a change from the traditional nest production towards an automated mass production, which requires the fulfillment of very high demands on precision and availability of the new technologies. In a research cooperation between industrial companies and research institutions skills were developed for an automated production of carbon fib er composite parts for aircraft industries. A major challenge of the project was the enormous demands on the quality and the necessary evidence. While in automotive industries quality control will normally be carried out by samples, in the aircraft industry a 100%-monitoring is necessary to assure the safety of the aircraft and to reduce financial risks for the involved enterprises. The manufacturing process of assembling the wing-cover components made of carbon fiber composite – titanium/aluminum structures consists primarily of the operations of drilling, reaming, removal of temporary rivets and placing the final rivets. With about 5,000 rivets the correct and flawless insertion of the holes is extremely important. Therefore a core area of the project was the line quality monitoring of a damage-free drilling of carbon-fiber composites. This included the automated measurement of all holes with respect to diameter, roundness and chamfer angle, but also the identification of possible delamination between layers of carbon fiber composites. Since the potential defects are not detectable using a single physical system, a platform for an open-system combination of various physical processes such as thermal imaging sensors, image processing and laser scanning systems was developed. In this way it is possible to compensate the disadvantages of the individual systems through the added properties of the corresponding systems. Via the developed system, the relevant features can be extracted from the raw data and fed into a generic rating classification system and a learning process. The addition of other sen

关键词： Quality Monitoring Multisensor System Thermography Laser Scanning Self-learning System Carbon Fiber Materials

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3D Polymer Weld Seam Characterization Based on Optical Coherence Tomography for Laser Transmission Welding Applications

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Physics Procedia 2014年 56卷 1305-1314页

作者： Robert Schmitt Guilherme Mallmann Martin Devrient Michael Schmidt Fraunhofer Institute for Production Technology IPT Steinbachstr. 17 Aachen Germany Laboratory for Machine Tools and Production Engineering WZL RWTH Aachen University Aachen Germany Bayerisches Laserzentrum GmbH (blz) Konrad-Zuse-Str. 2-6 91052 Erlangen Germany InstituteofPhotonic Technologies (LPT) Friedrich-Alexander-Universität Erlangen-Nürnberg Konrad-Zuse-Str. 3-5 91052 Erlangen Germany Erlangen Graduate School in Advanced Optical Technologies (SAOT) Friedrich-Alexander-Universität Erlangen-Nürnberg Paul-Gordan-Str. 6 91052 Erlangen Germany

Laser transmission welding is an established single-stage plastic joining process, which enables hermetically sealed joints under the workpiece surface. The process requires joining partners with proper degrees of transmission and absorption to the processing wavelength. For reaching a stable process an in-process quality assurance is very valuable. Current monitoring systems have a limited usage, as no quantitative information of the weld itself is obtained without its destruction. In medical and pharmaceutical applications a weld with leakage is e.g. unacceptable. The main objective of this paper is the presentation of the optical coherence tomography as a tool for the quality assurance in laser transmission welding. This approach enables the measurement of any residual gap, weld geometry, internal pores and leaks. The presented results show that this technique allows even the characterization of welds using joining partners with thicknesses of 2 mm or with glass fiber reinforcement levels of 30% per weight.

关键词： Laser transmission welding inline metrology frequency domain optical coherence tomography (FD-OCT) quality assurance

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Energy-sensitive production control in mixed model manufacturing processes 19

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19th CIRP Conference on Life Cycle Engineering, LCE 2012

作者： Neugebauer, Reimund Putz, Matthias Schlegel, Andreas Langer, Tino Franz, Enrico Lorenz, Sören Fraunhofer Institute Machine Tools and Forming Technology Chemnitz Germany

ISBN: (纸本)9783642290688

Although energy efficient production is a topic of high interest both in industrial practice and research, the need for a comprehensive analysis of energy considerations in production control of manufacturing processes at manufacturing control level has been largely ignored until now. This holds true especially for mixed-model production. The paper at hand discusses selected production control tasks, methods, processes and strategies for this production type and aims at identifying the extent to which energy features can be implemented into use, new and existing approaches and controlling tools. Based on first research activities, basic cases of energy-sensitive production control have been derived.

关键词： Energy efficiency

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Mathematical computations for linked data applications with openmath

Mathematical computations for linked data applications with ...

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Joint 24th Workshop on OpenMath and the 7th Workshop on Mathematical User Interfaces, MathUI 2012 and CICM Work in Progress - Conference on Intelligent Computer Mathematics, CICM 2012

作者： Wenzel, Ken Reinhardt, Heiner Fraunhofer-Institute for Machine Tools Forming Technology IWU Chemnitz Germany

Linked data can be used to connect information stemming from usually disparate sources. The Semantic Web combines various kinds of logical reasoning for the inference of additional knowledge from existing data and for consistency checking of data sets. Although mathematics is crucial for most areas where Semantic Web technologies can be applied, support for them is lacking from related standards and tools. This paper presents an approach for integrating OpenMath with RDF data for the representation of mathematical relationships and the integration of mathematical computations into reasoning systems.

关键词： Linked data

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