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Suche nach „[Mátéfi-Tempfli] [Stefan]“ hat 165 Publikationen gefunden
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    DigitalNachhaltigEuropan Campus Rottal-Inn

    Beitrag (Sammelband oder Tagungsband)

    A. Drimus, V. Jankovics, M. Gorsic, Stefan Mátéfi-Tempfli

    High Resolution Tactile Sensors for Curved Robotic Fingertips

    Biomimetic and Biohybrid Systems, Cham, vol. 8608 : Lecture notes in artificial intelligence

    2014

    ISBN: 978-3-319-09435-9

    DOI: 10.1007/978-3-319-09435-9_37

    Abstract anzeigen

    Tactile sensing is a key element for various animals that interact with the environment and surrounding objects. Touch provides information about contact forces, torques and pressure distribution and by the means of exploration it provides object properties such as geometry, stiffness and texture[5]. For humans, extracting high level information from touch provides a better understanding of the objects manipulated while for insects it is essential for locomotion[3]. While robot designers have been using vision systems to provide the robot with information about its surroundings, this is not always trivial to obtain, dealing with limited accuracy, occlusions and calibration problems. In terms of sensors for static stimuli, such as pressure, there are a range of technologies that can be used to manufacture transducers with various results[5]. A simple approach is to use fingertips with a 6-DOF force-torque sensor for estimating contact conditions[1], but this only allows a single point of contact and is costly. In terms of fingertip and foot tip prototypes, tactile sensors are used for multi modal sensing, similar to biology, for pressure and dynamic stimuli. In this respect Hosoda et al. [4] propose an anthropomorphic fingertip which has randomly distributed straingauges and PVDF (polyvinylidene fluoride) transducers. In [7] a biomimetic tactile array is proposed that shows a low hysteresis and good sensitivity for skin like deformations.

    DigitalEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    A. Drimus, V. Jankovics, M. Gorsic, Stefan Mátéfi-Tempfli

    Novel high resolution tactile robotic fingertips

    IEEE SENSORS, pp. 791-794

    2014

    DOI: 10.1109/ICSENS.2014.6985118

    Abstract anzeigen

    This paper describes a novel robotic fingertip based on piezoresistive rubber that can sense pressure tactile stimuli with a high spatial resolution over curved surfaces. The working principle is based on a three-layer sandwich structure (conductive electrodes on top and bottom and piezoresistive rubber in the middle). For the conductive layers we use ring patterns of silver epoxy and flex PCB electrode arrays. The proposed sensorised fingertip has 60 sensitive regions (taxels) arranged in 5 rings and 12 columns that have a smooth pressure to resistance characteristic. Using the sensor with specialized data acquisition electronics that acquire 500 frames per second provides rich information regarding contact force, shape and angle for bio-inspired robotic fingertips. Furthermore, a model of estimating the force of contact based on values of the cells is proposed.

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    G. Wittstock, G. Denuault, Stefan Mátéfi-Tempfli, H. Bülter, M. Mátéfi-Tempfli, A. Lesch, I. Schmidt, C. Dosche, M. Ahlf, K. Al-Shamery, A. Fanget, L. Forró

    Oxygen evolution at vertically aligned core-shell iron-iron oxide nanowire arrays

    24th ECS Meeting: Photoelectrochemistry and Photoassisted Electrocatalysis, San Francisco, CA, USA

    2013

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    A. Goszczak, M. Madsen, J. Hoyland, Stefan Mátéfi-Tempfli, H-G. Rubahn

    Nanostructures for organic solar cells

    NANOTEXNOLOGY 2013, Thessaloniki, Griechenland

    2013

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    Stefan Mátéfi-Tempfli

    Nanostructured materials and interfaces for enhancing photoelectrical and photoelectrochemical conversion

    Invited lecture

    Physics and Chemistry of Advanced Materials (PCAM) European network summer school, Lago di Como, Italien

    2013

    NachhaltigEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    O. Dmytriiev, U.A.S. Al-Jarah, Gangmei P., V. Kruglyak, R. Hicken, B. Mahato, B. Rana, M. Agrawal, A. Barman, M. Mátéfi-Tempfli, L. Piraux, Stefan Mátéfi-Tempfli

    Static and dynamic magnetic properties of densely packed magnetic nanowire arrays

    Physical Review B, vol. 87, no. 17

    2013

    DOI: 10.1103/PhysRevB.87.174429

    Abstract anzeigen

    The static and dynamic magnetic properties of magnetic nanowire arrays with high packing density (>0.4) and wire diameter much greater than the exchange length have been studied by static and time-resolved magneto-optical Kerr effect measurements and micromagnetic simulations. The nanowires were formed by electrodeposition within a nanoporous template such that their symmetry axes lay normal to the plane of the substrate. A quantitative and systematic investigation has been made of the static and dynamic properties of the array, which lie between the limiting cases of a single wire and a continuous ferromagnetic thin film. In particular, the competition between anisotropies associated with the shape of the individual nanowires and that of the array as a whole has been studied. Measured and simulated hysteresis loops are largely anhysteretic with zero remanence, and the micromagnetic configuration is such that the net magnetization vanishes in directions orthogonal to the applied field. Simulations of the remanent state reveal antiferromagnetic alignment of the magnetization in adjacent nanowires and the formation of vortex flux closure structures at the ends of each nanowire. The excitation spectra obtained from experiment and micromagnetic simulations are in qualitative agreement for magnetic fields applied both parallel and perpendicular to the axes of the nanowires. For the field parallel to the nanowire axes, there is also good quantitative agreement between experiment and simulation. The resonant frequencies are initially found to decrease as the applied field is increased from remanence. This is the result of a change of mode profile within the plane of the array from nonuniform to uniform as the ground state evolves with increasing applied field. Quantitative differences between experimental and simulated spectra are observed when the field is applied perpendicular to the nanowire axes. The dependence of the magnetic excitation spectra upon the array packing density is explored, and dispersion curves for spin waves propagating within the array parallel to the nanowire axis are presented. Finally, a tunneling of end modes through the middle region of the nanowires was observed. The tunneling is more efficient for wires forming densely packed arrays, as a result of the extended penetration of the dynamic demagnetizing fields into the middle of the wires and due to the lowering of the tunneling barrier by the static demagnetizing field of the array.

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    H. Bülter, G. Wittstock, Stefan Mátéfi-Tempfli, M. Mátéfi-Tempfli, G. Denuault

    Scanning electrochemical microscopy : Investigation of oxygen evolution from nanostructured iron oxide films and nanowires.

    Electrochemistry 2012: Fundamental and Engineering Needs for Sustainable Development, München

    2012

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    H. Bülter, G. Wittstock, Stefan Mátéfi-Tempfli, M. Mátéfi-Tempfli, G. Denuault

    Scanning electrochemical microscopy: Investigation of oxygen evolution from nanostructured iron oxide films and nanowires

    12th International Fischer Symposium "Frontiers in Nanoelectrochemistry", Lübeck

    2012

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    H. Bülter, G. Wittstock, Stefan Mátéfi-Tempfli, M. Mátéfi-Tempfli, G. Denuault

    Scanning electrochemical microscopy : Investigation of oxygen evolution from nanostructured iron oxide fims and nanowires

    23rd Lecture Conference on Photochemistry, Potsdam

    2012

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    Stefan Mátéfi-Tempfli

    Harvesting energy from the environment :Toward cleaner, safer and more efficient approaches

    Fellow lecture

    Hanse-Wissenschaftskolleg Institute for Advanced Study, Delmenhorst

    2012

    NachhaltigEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    A. Milosavljević, K. Schiessl, C. Lemell, K. Tökési, M. Mátéfi-Tempfli, Stefan Mátéfi-Tempfli, B. Marinković, J. Burgdörfer

    Charging dynamics in electron transmission through Al2O3 capillaries

    Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, vol. 279, pp. 190-193

    2012

    Abstract anzeigen

    We have measured the transmission of low-energy electrons through insulating Al2O3 nanocapillaries. We find that transmission at the incident energy is quickly suppressed with increasing tilt angle of the capillary axis relative to the incoming electron beam while inelastic transmission becomes more important. For small angles of incidence charging dynamics lead to a decrease of total transmission (elastic and inelastic) with time. Our results are interpreted on the basis of a microscopic model for the electron transport within the capillary including also close interactions with the capillary wall.

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    Stefan Mátéfi-Tempfli

    Nanomaterials synthesis and applications

    Invited talk

    2011

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    Stefan Mátéfi-Tempfli

    Electrochemical template synthesis of nanostructures

    Invited seminar

    Institute of Condensed Matter Physics - Nanostructured & Complex Matter, Lausanne, Schweiz

    2011

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    Stefan Mátéfi-Tempfli

    Combining electrochemical template synthesis with classical lithography methods of micro- and nanopatterning

    Invited seminar

    Physical Chemistry Symposium of the Center of Interface Science, Oldenburg

    2011

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    Stefan Mátéfi-Tempfli

    Nanostructured materials and applications

    Invited talk

    Centre for NanoHealth, College of Medicine and School of Engineering, Swansea University, Swansea, Großbritannien

    2011

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    Stefan Mátéfi-Tempfli

    Combining electrochemical template synthesis with classical lithography methods of micro and nano-patterning

    Invited talk

    2011

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    A. Milosavljević, K. Schiessl, C. Lemell, K. Tökési, M. Mátéfi-Tempfli, Stefan Mátéfi-Tempfli, B. Marinković, J. Burgdörfer

    Charging dynamics in electron transmission through Al2O3 capillaries

    5th Conference on Elementary Processes in Atomic Systems (CEPAS 2011), Belgrad, Serbien

    2011

    NachhaltigEuropan Campus Rottal-Inn

    Vortrag

    A. Milosavljević, J. Jureta, Gy. Vikor, Z. Pešić, D. Šević, Stefan Mátéfi-Tempfli, M. Mátéfi-Tempfli, B. Marinković

    Guiding of low-energy electrons by Al2O3 nanocapillaries.

    XXVII International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC 2011), Belfast, Nordirland, Großbritannien

    2011

    NachhaltigEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    S. Habouti, M. Mátéfi-Tempfli, C.-H. Solterbeck, M. Es-Souni, Stefan Mátéfi-Tempfli

    On-substrate, self-standing Au-nanorods arrays showing morphology controlled properties

    Nano Today, vol. 6, no. 1, pp. 12-19

    2011

    DOI: 10.1016/j.nantod.2010.11.001

    Abstract anzeigen

    We use supported alumina templates and electrodeposition to fabricate self-standing Au-nanorods (Au-NR) arrays. Depending on electrolyte and deposition conditions two different NR morphologies with either corrugated or smooth topologies are fabricated. We show that the properties of the NR arrays, including amphiphilic and optical, very much depend on their morphology. Smooth NR arrays are hydrophobic while the corrugated ones are hydrophilic. Also the optical reflectance, though it shows plasmon resonances at very similar wave lengths, is much lower for the corrugated NR arrays. The activity of the NR arrays as substrates for molecular detection using Raman scattering, and Rhodamine 6G (R6G) as model dye, also strongly depends on their morphology. R6G concentrations down to 1 pM are detected on the corrugated arrays yielding an effective enhancement factor (EF) of approximately 1 × 109. In contrast an over-estimated (because of their hydrophobic character) EF of 6 × 106 is obtained for the smooth NR arrays.

    NachhaltigEuropan Campus Rottal-Inn

    Zeitschriftenartikel

    V. Antohe, A. Radu, Stefan Mátéfi-Tempfli, L. Piraux

    Circuit Modeling on Polyaniline Functionalized Nanowire-Templated Micro-Interdigital Capacitors for pH Sensing

    IEEE Transactions on Nanotechnology, vol. 10, no. 6, pp. 1314-1320

    2011

    Abstract anzeigen

    This study presents an improved alternative current (ac) circuit modeling of a highly sensitive capacitive pH-sensing element based on polyaniline (PANI) functionalized nanowire-templated micro-interdigited electrodes (NWs μIDEs). While electrical resonance measurements deal with a total equivalent capacity, comparative investigations show a good agreement with the fitting parameters of the corresponding model. A physical interpretation of the model is discussed to help in understanding the detection mechanism and a possible methodology to be used for further integration of the subsequent device is suggested.