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Riedel S.L.,TU Berlin | Riedel S.L.,Fraunhofer Institute for Production Systems and Design Technology | Lu J.,Massachusetts Institute of Technology | Stahl U.,TU Berlin | Brigham C.J.,University of Massachusetts Dartmouth
Applied Microbiology and Biotechnology | Year: 2014

Lipid and fatty acid metabolism has been well studied in model microbial organisms like Escherichia coli and Bacillus subtilis. The major precursor of fatty acid biosynthesis is also the major product of fatty acid degradation (β-oxidation), acetyl-CoA, which is a key metabolite for all organisms. Controlling carbon flux to fatty acid biosynthesis and from β-oxidation allows for the biosynthesis of natural products of biotechnological importance. Ralstonia eutropha can utilize acetyl-CoA from fatty acid metabolism to produce intracellular polyhydroxyalkanoate (PHA). R. eutropha can also be engineered to utilize fatty acid metabolism intermediates to produce different PHA precursors. Metabolism of lipids and fatty acids can be rerouted to convert carbon into other value-added compounds like biofuels. This review discusses the lipid and fatty acid metabolic pathways in R. eutropha and how they can be used to construct reagents for the biosynthesis of products of industrial importance. Specifically, how the use of lipids or fatty acids as the sole carbon source in R. eutropha cultures adds value to these biotechnological products will be discussed here. © 2013 Springer-Verlag Berlin Heidelberg. Source

Woll R.,Fraunhofer Institute for Production Systems and Design Technology
Advanced Concurrent Engineering | Year: 2013

Along the product development process concurrent engineering teams repeatedly create new product data and exchange it among each other as a logical input for subsequent engineering activities. Almost every piece of product data logically builds on another. However, usually product data is scattered over different, domain-specific IT systems and this physical separation is a challenge for product developers and IT experts. Since the management of logical interrelations between distributed product data is costly, such semantic links are often not modelled explicitly. Hence, engineers need to know these interrelations implicitly in order to ensure logical consistency of the overall product model. In this paper an approach for efficient semantic data integration and its application to an exemplary use case, knowledge-based test planning, is presented. It is supported by an integration framework that uses ontologies for interlinking different systems of virtual product creation. The paper also presents the findings of a case study on the process of defining a mapping between a requirements ontology and a domainspecific data exchange format, the Requirements Interchange Format (ReqIF). © Springer-Verlag London 2013. Source

News Article
Site: http://phys.org/technology-news/

Underlying the term Industrie 4.0 is the idea that in the factory of the future, machines will communicate directly with each other, with workpieces and with human workers. The ultimate goal is for production to organize itself. Experts hope that Industrie 4.0 will provide a more flexible production setup and the ability to respond to customer wishes more quickly. It is precisely this goal that the Fraunhofer Institute for Production Systems and Design Technology IPK aims to achieve by putting people at the center. Human workers wield the power to make decisions about the production sequence, and receive help in making those decisions from high-performance tools. The Fraunhofer research scientists use gear manufacturing as an example to illustrate what this means. Presently, gears are manufactured in firmly linked lines that connect, say, milling machines and turning machines to each other in a chain. If one machine goes offline, the entire line shuts down. Another drawback with line production is that it is expensive and time-consuming, if not actually impossible, to execute small and very small orders that have special requirements or product features. "If you want production to be more flexible, it is a promising idea to break up the chains," says Eckhard Hohwieler, head of IPK's Production Machines and Systems Management department. "But that's harder than it sounds." One alternative to the line concept is workshop production. In this configuration, machines that carry out similar tasks are grouped together in cells – for example, several turning machines are clustered in a turning-machine cell or several milling machines become a milling-machine cell. However, as Hohwieler points out, "if you do that, you need methods that guarantee products will progress swiftly and reliably through the entire production process. Otherwise a work step may be left out or an order might get stuck halfway through production because no one knows where to send it next." Here's where IPK research comes in. At Hannover Messe 2016, the Berlin-based research team will present an integrated Industrie 4.0 factory that replaces fixed links with a new kind of process organization without sacrificing the reliability of line production. In this factory, IT driven tools ensure that employees at all hierarchy levels receive the information they need at any time in order to play their part in the punctual manufacturing of the product – whether it be in process management, production planning, or final assembly. One aspect of the factory will be on display at the Hannover Messe Preview on January 27. The iWePro project, which focuses on intelligent cooperation and networking for workshop production, brings together IPK engineers and industry partners to explore how gear manufacturing can be reliably managed on the shop floor without linking machines into chains. "Until now, the entire production process – all the way from the blank to a ready-to-use gear – was planned out in advance and then simply carried out," explains Franz Otto, a research fellow at IPK. To make it possible to manage workshop orders as the situation demands, he and his colleagues are currently developing an agent system that monitors implementation of the production plan. The agents – components of the agent system software – supply employees at the various workshop stations with information such as which machine is slated for the next processing step. They can also provide assistance when ad hoc rescheduling is required, for example if a machine stops working. "But before production cells can become a reality, we have to investigate whether they are in fact an alternative to conventional line production, which is already quite sophisticated," says Otto. To that end, iWePro generates an elaborate simulation that the researchers can run to determine which combination of centralized planning and flexible adaptation is suitable for which use case – which interventions by workers make sense. The simulation also addresses how to provide the necessary detailed information to workers on the shop floor; for example, by means of smart devices. The simulation of workshop production, to be shown during the Preview and later at Hannover Messe (Hall 17, Booth C18), creates a 3D image of all processes in produc-tion. "This echoes the view from a control station," explains Hohwieler. At Hannover Messe, the researchers will combine the simulation with a model-driven industry cockpit and a two-armed assembly robot. The cockpit enables managers to flexibly

Uhlmann E.,TU Berlin | Uhlmann E.,Fraunhofer Institute for Production Systems and Design Technology | Domingos D.C.,Fraunhofer Institute for Production Systems and Design Technology
Procedia CIRP | Year: 2013

Modern aircraft engines are nowadays designed with the aim of reducing fuel consumption and emission of pollutant gases as well as increasing reliability and competitiveness in the manufacturing and repair costs. These requirements on the engines result in new requirements on components and manufacturing processes, to know: application of new engineering materials, higher component temperatures, increased demands on tightness, 3-D complex shapes as well as new manufacturing technologies. EDM-machining is typically chosen for applications including complex geometries like high aspect ratio cavities in high-temperature resistant materials, since the EDM-process is independent from the mechanical properties of the processed material. This paper addresses the design and utilization of a unit composed of piezoelectric actuators for machining seal slots in turbine components. This aims the optimization of the flushing mechanisms through vertical vibration of the tool electrodes while manufacturing high aspect ratios cavities and therewith the optimization and/or reduction of both process time and electrode wear. Firstly, the piezo-unit was designed and components like piezoelectric actuators and charge amplifier were chosen, in accordance to previous defined requirements regarding vibration frequencies and amplitudes. During the experimental investigations graphite electrodes were applied. A total of twelve cavities with an aspect ratio of 12 are simultaneously machined in the material MAR-247. During the process, a harmonic longitudinal vibration of the electrodes overlapped to the machine's feed movement is realized. Both vibration amplitude and frequency were varied during the experiments, ranging from 2 μm to 16 μm and from 50 Hz to 1 kHz, respectively. The results are compared to the conventional process without vibration, while the EDM-parameters remain unaltered. By applying longitudinal vibration to the tool electrodes the material removal rate was increased by 11 %. The relative tool electrode wear was reduced by 21 %. © 2013 The Authors. Source

Kruger J.,TU Berlin | Kruger J.,Fraunhofer Institute for Production Systems and Design Technology | Schreck G.,Fraunhofer Institute for Production Systems and Design Technology | Surdilovic D.,Fraunhofer Institute for Production Systems and Design Technology
CIRP Annals - Manufacturing Technology | Year: 2011

Dual-arm robots provide efficient approach for automated execution of complex assembly operations. With bimanual-manipulation, a dual-arm robot can simultaneously control relative motion and interaction of assembly counterparts in a dexterous human-like manner. This requires, however, sophisticated programming and control algorithms for arms cooperation. This paper addresses the development of an advanced industrial dual-arm robot system with novel capabilities, such as easy and rapid commissioning, compliance control of bimanual interaction in all assembly process phases, as well as intuitive planning and programming. The robot can be leased and easily integrated in assembly environment sharing the same workspace with human workers. © 2011 CIRP. Source

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