Header logo is


2020


Thumb xl hetl
Hierarchical Event-triggered Learning for Cyclically Excited Systems with Application to Wireless Sensor Networks

Beuchert, J., Solowjow, F., Raisch, J., Trimpe, S., Seel, T.

IEEE Control Systems Letters, 4(1):103-108, January 2020 (article) To be published

ics

arXiv PDF DOI [BibTex]

2020


arXiv PDF DOI [BibTex]


Thumb xl l css
Control-guided Communication: Efficient Resource Arbitration and Allocation in Multi-hop Wireless Control Systems

Baumann, D., Mager, F., Zimmerling, M., Trimpe, S.

IEEE Control Systems Letters, 4(1):127-132, January 2020 (article) To be published

ics

arXiv PDF DOI [BibTex]

arXiv PDF DOI [BibTex]


no image
Fabrication and temperature-dependent magnetic properties of large-area L10-FePt/Co exchange-spring magnet nanopatterns

Son, K., Schütz, G.

{Physica E: Low-Dimensional Systems And Nanostructures}, 115, North-Holland, Amsterdam, 2020 (article)

mms

DOI [BibTex]

DOI [BibTex]

2015


no image
Distributed Event-based State Estimation

Trimpe, S.

Max Planck Institute for Intelligent Systems, November 2015 (techreport)

Abstract
An event-based state estimation approach for reducing communication in a networked control system is proposed. Multiple distributed sensor-actuator-agents observe a dynamic process and sporadically exchange their measurements and inputs over a bus network. Based on these data, each agent estimates the full state of the dynamic system, which may exhibit arbitrary inter-agent couplings. Local event-based protocols ensure that data is transmitted only when necessary to meet a desired estimation accuracy. This event-based scheme is shown to mimic a centralized Luenberger observer design up to guaranteed bounds, and stability is proven in the sense of bounded estimation errors for bounded disturbances. The stability result extends to the distributed control system that results when the local state estimates are used for distributed feedback control. Simulation results highlight the benefit of the event-based approach over classical periodic ones in reducing communication requirements.

am ics

arXiv [BibTex]

2015


arXiv [BibTex]


Thumb xl posterior
Automatic LQR Tuning Based on Gaussian Process Optimization: Early Experimental Results

Marco, A., Hennig, P., Bohg, J., Schaal, S., Trimpe, S.

Machine Learning in Planning and Control of Robot Motion Workshop at the IEEE/RSJ International Conference on Intelligent Robots and Systems (iROS), pages: , , Machine Learning in Planning and Control of Robot Motion Workshop, October 2015 (conference)

Abstract
This paper proposes an automatic controller tuning framework based on linear optimal control combined with Bayesian optimization. With this framework, an initial set of controller gains is automatically improved according to a pre-defined performance objective evaluated from experimental data. The underlying Bayesian optimization algorithm is Entropy Search, which represents the latent objective as a Gaussian process and constructs an explicit belief over the location of the objective minimum. This is used to maximize the information gain from each experimental evaluation. Thus, this framework shall yield improved controllers with fewer evaluations compared to alternative approaches. A seven-degree-of-freedom robot arm balancing an inverted pole is used as the experimental demonstrator. Preliminary results of a low-dimensional tuning problem highlight the method’s potential for automatic controller tuning on robotic platforms.

am ei ics pn

PDF DOI Project Page [BibTex]

PDF DOI Project Page [BibTex]


Thumb xl mt cover
Gaussian Process Optimization for Self-Tuning Control

Marco, A.

Polytechnic University of Catalonia (BarcelonaTech), October 2015 (mastersthesis)

am ics

PDF Project Page [BibTex]

PDF Project Page [BibTex]


no image
Adaptive and Learning Concepts in Hydraulic Force Control

Doerr, A.

University of Stuttgart, September 2015 (mastersthesis)

am ics

[BibTex]

[BibTex]


Thumb xl screen shot 2015 08 22 at 21.47.37
Direct Loss Minimization Inverse Optimal Control

Doerr, A., Ratliff, N., Bohg, J., Toussaint, M., Schaal, S.

In Proceedings of Robotics: Science and Systems, Rome, Italy, Robotics: Science and Systems XI, July 2015 (inproceedings)

Abstract
Inverse Optimal Control (IOC) has strongly impacted the systems engineering process, enabling automated planner tuning through straightforward and intuitive demonstration. The most successful and established applications, though, have been in lower dimensional problems such as navigation planning where exact optimal planning or control is feasible. In higher dimensional systems, such as humanoid robots, research has made substantial progress toward generalizing the ideas to model free or locally optimal settings, but these systems are complicated to the point where demonstration itself can be difficult. Typically, real-world applications are restricted to at best noisy or even partial or incomplete demonstrations that prove cumbersome in existing frameworks. This work derives a very flexible method of IOC based on a form of Structured Prediction known as Direct Loss Minimization. The resulting algorithm is essentially Policy Search on a reward function that rewards similarity to demonstrated behavior (using Covariance Matrix Adaptation (CMA) in our experiments). Our framework blurs the distinction between IOC, other forms of Imitation Learning, and Reinforcement Learning, enabling us to derive simple, versatile, and practical algorithms that blend imitation and reinforcement signals into a unified framework. Our experiments analyze various aspects of its performance and demonstrate its efficacy on conveying preferences for motion shaping and combined reach and grasp quality optimization.

am ics

PDF Video Project Page [BibTex]

PDF Video Project Page [BibTex]


no image
LMI-Based Synthesis for Distributed Event-Based State Estimation

Muehlebach, M., Trimpe, S.

In Proceedings of the American Control Conference, July 2015 (inproceedings)

Abstract
This paper presents an LMI-based synthesis procedure for distributed event-based state estimation. Multiple agents observe and control a dynamic process by sporadically exchanging data over a broadcast network according to an event-based protocol. In previous work [1], the synthesis of event-based state estimators is based on a centralized design. In that case three different types of communication are required: event-based communication of measurements, periodic reset of all estimates to their joint average, and communication of inputs. The proposed synthesis problem eliminates the communication of inputs as well as the periodic resets (under favorable circumstances) by accounting explicitly for the distributed structure of the control system.

am ics

PDF DOI Project Page [BibTex]

PDF DOI Project Page [BibTex]


no image
Guaranteed H2 Performance in Distributed Event-Based State Estimation

Muehlebach, M., Trimpe, S.

In Proceeding of the First International Conference on Event-based Control, Communication, and Signal Processing, June 2015 (inproceedings)

am ics

PDF DOI Project Page [BibTex]

PDF DOI Project Page [BibTex]


no image
On the Choice of the Event Trigger in Event-based Estimation

Trimpe, S., Campi, M.

In Proceeding of the First International Conference on Event-based Control, Communication, and Signal Processing, June 2015 (inproceedings)

am ics

PDF DOI Project Page [BibTex]

PDF DOI Project Page [BibTex]


no image
Event-based Estimation and Control for Remote Robot Operation with Reduced Communication

Trimpe, S., Buchli, J.

In Proceedings of the IEEE International Conference on Robotics and Automation, May 2015 (inproceedings)

Abstract
An event-based communication framework for remote operation of a robot via a bandwidth-limited network is proposed. The robot sends state and environment estimation data to the operator, and the operator transmits updated control commands or policies to the robot. Event-based communication protocols are designed to ensure that data is transmitted only when required: the robot sends new estimation data only if this yields a significant information gain at the operator, and the operator transmits an updated control policy only if this comes with a significant improvement in control performance. The developed framework is modular and can be used with any standard estimation and control algorithms. Simulation results of a robotic arm highlight its potential for an efficient use of limited communication resources, for example, in disaster response scenarios such as the DARPA Robotics Challenge.

am ics

PDF DOI Project Page [BibTex]

PDF DOI Project Page [BibTex]


no image
Lernende Roboter

Trimpe, S.

In Jahrbuch der Max-Planck-Gesellschaft, Max Planck Society, May 2015, (popular science article in German) (inbook)

am ics

link (url) [BibTex]

link (url) [BibTex]


no image
Policy Search for Imitation Learning

Doerr, A.

University of Stuttgart, January 2015 (thesis)

am ics

link (url) Project Page [BibTex]

link (url) Project Page [BibTex]


no image
Isosteric heat of hydrogen adsorption on MOFs: comparison between adsorption calorimetry, sorption isosteric metod, and analytical models

Kloutse, A. F., Zacharia, R., Cossement, D., Chahine, R., Balderas-Xicohténcatl, R., Oh, H., Streppel, B., Schlichtenmayer, M., Hirscher, M.

{Applied Physics A}, 121(4):1417-1424, Springer-Verlag Heidelberg, Heidelberg, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
A New Perspective and Extension of the Gaussian Filter

Wüthrich, M., Trimpe, S., Kappler, D., Schaal, S.

In Robotics: Science and Systems, 2015 (inproceedings)

Abstract
The Gaussian Filter (GF) is one of the most widely used filtering algorithms; instances are the Extended Kalman Filter, the Unscented Kalman Filter and the Divided Difference Filter. GFs represent the belief of the current state by a Gaussian with the mean being an affine function of the measurement. We show that this representation can be too restrictive to accurately capture the dependencies in systems with nonlinear observation models, and we investigate how the GF can be generalized to alleviate this problem. To this end we view the GF from a variational-inference perspective, and analyze how restrictions on the form of the belief can be relaxed while maintaining simplicity and efficiency. This analysis provides a basis for generalizations of the GF. We propose one such generalization which coincides with a GF using a virtual measurement, obtained by applying a nonlinear function to the actual measurement. Numerical experiments show that the proposed Feature Gaussian Filter (FGF) can have a substantial performance advantage over the standard GF for systems with nonlinear observation models.

am ics

Web PDF Project Page [BibTex]


no image
Time-resolved imaging of pulse-induced magnetization reversal with a microwave assist field

Rao, S., Rhensius, J., Bisig, A., Mawass, M.-A., Weigand, M., Kläui, M., Bhatia, C. S., Yang, H.

{Scientific Reports}, 5, Nature Publishing Group, London, UK, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
XMCD studies of thin Co films on BaTiO3

Welke, M., Gräfe, J., Govind, R. K., Babu, V. H., Trautmann, M., Schindler, K., Denecke, R.

{Journal of Physics: Condensed Matter}, 27(32), IOP Publishing, Bristol, UK, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Combined FORC and x-ray microscopy study of magnetisation reversal in antidot lattices

Gräfe, J., Haering, F., Stahl, C., Weigand, M., Skripnik, M., Nowak, U., Ziemann, P., Wiedwald, U., Schütz, G., Goering, E.

In IEEE International Magnetics Conference (INTERMAG 2015), IEEE, Beijing, China, 2015 (inproceedings)

mms

DOI Project Page Project Page [BibTex]

DOI Project Page Project Page [BibTex]


no image
Low temperature X-ray imaging of magnetic flux patterns in high temperature superconductors

Stahl, C., Ruoß, S., Weigand, M., Bechtel, M., Schütz, G., Albrecht, J.

{Journal of Applied Physics}, 117(17), AIP Publishing, New York, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Local control of domain wall dynamics in ferromagnetic rings

Richter, K., Mawass, M., Krone, A., Krüger, B., Weigand, M., Stoll, H., Schütz, G., Kläui, M.

In IEEE International Magnetics Conference (INTERMAG 2015), IEEE, Beijing, China, 2015 (inproceedings)

mms

DOI [BibTex]

DOI [BibTex]


no image
Formation of a quasi-solid structure by intercalated noble gas atoms in pores of CuI-MFU-4l metal-organic framework

Magdysyuk, O. V., Denysenko, D., Weinrauch, I., Volkmer, D., Hirscher, M., Dinnebier, R. E.

{Chemical Communications}, 51(4):714-717, Royal Society of Chemistry, Cambridge, UK, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Burst-mode manipulation of magnonic vortex crystals

Hänze, M., Adolff, C. F., Weigand, M., Meier, G.

{Physical Review B}, 91(10), American Physical Society, Woodbury, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Strukturelle und spektroskopische Eigenschaften epitaktischer FeMn/Co Exchange-Bias-Systeme

Schmidt, M.

Universität Stuttgart, Stuttgart, 2015 (phdthesis)

mms

link (url) DOI [BibTex]


no image
Fabrication and X-ray testing of true kinoform lenses with high efficiencies

Keskinbora, K., Sanli, U., Grévent, C., Schütz, G.

{Proceedings of SPIE}, 9592, SPIE, Bellingham, Washington, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Ultraschnelles Vortexkernschalten

Noske, M.

Universität Stuttgart, Stuttgart (und Cuvillier Verlag, Göttingen), 2015 (phdthesis)

mms

[BibTex]

[BibTex]


no image
Investigations of unusual hard magnetic MnBi LTP phase, utilizing temperature dependent SQUID-FORC

Muralidhar, Shreyas

Universität Stuttgart, Stuttgart, 2015 (mastersthesis)

mms

[BibTex]

[BibTex]


no image
Magnetische Röntgenmikroskopie an Hochtemperatur-Supraleitern

Stahl, C.

Universität Stuttgart, Stuttgart (und Cuvillier Verlag, Göttingen), 2015 (phdthesis)

mms

[BibTex]

[BibTex]


no image
Focused ion beam micromachining enables novel optics for X-ray microscopy

Keskinbora, K., Sanli, U., Grévent, C., Hirscher, M., Schütz, G.

{Microscopy and Microanalysis}, 21(Suppl 3):1983-1984, Springer-Verlag New York, New York, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Selectable nanopattern arrays for nanolithographic imprint and etch-mask applications

Jeong, H., Mark, A. G., Lee, T., Son, K., Chen, W., Alarcón-Correa, M., Kim, I., Schütz, G., Fischer, P.

{Advanced Science}, 2(2), Wiley-VCH, Weinheim, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Grain boundaries as a source of ferromagnetism and increased solubility of Ni in nanograined ZnO

Straumal, B. B., Mazilkin, A. A., Protasova, S. G., Stakhanova, S. V., Straumal, P. B., Bulatov, M. F., Schütz, G., Tietze, T., Goering, E., Baretzky, B.

{Reviews on Advanced Materials Science}, 41, pages: 61-71, 2015 (article)

mms

[BibTex]

[BibTex]


no image
Gyrational modes of benzenelike magnetic vortex molecules

Adolff, C. F., Hänze, M., Pues, M., Weigand, M., Meier, G.

{Physical Review B}, 92(2), American Physical Society, Woodbury, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
"Job-Sharing" storage of hydrogen in Ru/Li2O nanocomposites

Fu, L., Tang, K., Oh, H., Kandavel, M., Bräuniger, T., Vinod Chandran, C., Menzel, A., Hirscher, M., Samuelis, D., Maier, J.

{Nano Letters}, 15(6):4170-4175, American Chemical Society, Washington, DC, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Overview of the multilayer-Fresnel zone plate and the kinoform lens development at MPI for Intelligent Systems

Sanli, U., Keskinbora, K., Grévent, C., Schütz, G.

{Proceedings of SPIE}, 9510, SPIE, Bellingham, Washington, 2015 (article)

mms

DOI [BibTex]


no image
Transition matrix elements for electron-phonon scattering: Phenomenological theory and ab initio electron theory

Illg, C., Haag, M., Müller, B. Y., Czycholl, G., Fähnle, M.

{Physical Review B}, 92(19), American Physical Society, Woodbury, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Phase evolution in single-crystalline LiFePO4 followed by in situ scanning X-ray microscopy of a micrometre-sized battery

Ohmer, N., Fenk, B., Samuelis, D., Chen, C., Maier, J., Weigand, M., Goering, E., Schütz, G.

{Nature Communications}, 6, Nature Publishing Group, London, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Nitrogen-rich covalent triazine frameworks as high-performance platforms for selective carbon capture and storage

Hug, S., Stegbauer, L., Oh, H., Hirscher, M., Lotsch, B. V.

{Chemistry of Materials}, 27(23):8001-8010, American Chemical Society, Washington, D.C., 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Multilayer Fresnel zone plates for X-ray microscopy

Sanli, U. T., Keskinbora, K., Grévent, C., Szeghalmi, A., Knez, M., Schütz, G.

{Microscopy and Microanalysis}, 21(Suppl 3):1987-1988, Springer-Verlag New York, New York, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Interfacial dominated ferromagnetism in nanograined ZnO: a \muSR and DFT study

Tietze, T., Audehm, P., Chen, Y., Schütz, G., Straumal, B. B., Protasova, S. G., Mazilkin, A. A., Straumal, P. B., Prokscha, T., Luetkens, H., Salman, Z., Suter, A., Baretzky, B., Fink, K., Wenzel, W., Danilov, D., Goering, E.

{Scientific Reports}, 5, pages: 8871-8876, Nature Publishing Group, London, UK, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Preparation of a ferromagnetic barrier in YBa2Cu3O7-delta thinner than the coherence length

Soltan, S., Albrecht, J., Goering, E., Schütz, G., Mustafa, L., Keimer, B., Habermeier, H.

{Journal of Applied Physics}, 118(22), AIP Publishing, New York, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Microanalytical methods for in-situ high-resolution analysis of rock varnish at the micrometer to nanometer scale

Macholdt, D. S., Jochum, K. P., Pöhlker, C., Stoll, B., Weis, U., Weber, B., Müller, M., Kapl, M., Buhre, S., Kilcoyne, A. L. D., Weigand, M., Scholz, D., Al-Amri, A. M., Andreae, M. O.

{Chemical Geology}, 411, pages: 57-68, Elsevier, Amsterdam, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Chemical composition, microstructure, and hygroscopic properties of aerosol particles at the Zotino Tall Tower Observatory (ZOTTO), Siberia, during a summer campaign

Mikhailov, E. F., Mironov, G. N., Pöhlker, C., Chi, X., Krüger, M., Shiraiwa, M., Förster, J., Pöschl, U., Vlasenko, S. S., Ryshkevich, T. I., Weigand, M., Kilcoyne, A. L. D., Andreae, M.

{Atmospheric Chemistry and Physics}, 15(15):8847-8869, European Geosciences Union, Katlenburg-Lindau, Germany, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Orbital reflectometry of PrNiO3/PrAlO3 superlattices

Wu, M., Benckiser, E., Audehm, P., Goering, E., Wochner, P., Christiani, G., Logvenov, G., Habermeier, H., Keimer, B.

{Physical Review B}, 91(19), American Physical Society, Woodbury, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Dynamic domain wall chirality rectification by rotating magnetic fields

Bisig, A., Mawass, M., Stärk, M., Moutafis, C., Rhensius, J., Heidler, J., Gliga, S., Weigand, M., Tyliszczak, T., Van Waeyenberge, B., Stoll, H., Schütz, G., Kläui, M.

{Applied Physics Letters}, 106(12), American Institute of Physics, Melville, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Ultrafast demagnetization after laser pulse irradiation in Ni: Ab-initio electron-phonon scattering and phase space calculations

Illg, C., Haag, M., Fähnle, M.

In Ultrafast Magnetism I. Proceedings of the International Conference UMC 2013, 159, pages: 131-133, Springer Proceedings in Physics, Springer, Strasbourg, 2015 (inproceedings)

mms

DOI [BibTex]

DOI [BibTex]


no image
Imaging spin dynamics on the nanoscale using X-ray microscopy

Stoll, H., Noske, M., Weigand, M., Richter, K., Krüger, B., Reeve, R. M., Hänze, M., Adolff, C. F., Stein, F., Meier, G., Kläui, M., Schütz, G.

{Frontiers in Physics}, 3, Frontiers Media, Lausanne, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Voltage-induced magnetic manipulation of a microstructured iron gold multilayer system

Sittig, Robert

Universität Stuttgart, Stuttgart, 2015 (mastersthesis)

mms

[BibTex]

[BibTex]


no image
Unique high-temperature performance of highly consensed MnBi permanent magnets

Chen, Y., Gregori, G., Leineweber, A., Qu, F., Chen, C., Tietze, T., Kronmüller, H., Schütz, G., Goering, E.

{Scripta Materialia}, 107, pages: 131-135, Pergamon, Tarrytown, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]


no image
Electrical determination of vortex state in submicron magnetic elements

Gangwar, A., Bauer, H. G., Chauleau, J., Noske, M., Weigand, M., Stoll, H., Schütz, G., Back, C. H.

{Physical Review B}, 91(9), American Physical Society, Woodbury, NY, 2015 (article)

mms

DOI [BibTex]

DOI [BibTex]