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Procedia CIRP 2020年 93卷 32-37页

作者： Mandaná Moshiri Amal Charles Ahmed Elkaseer Steffen Scholz Sankhya Mohanty Guido Tosello Department of Mechanical Engineering Technical University of Denmark Building 427 Produktionstorvet 5 DK-2800 Kgs. Lyngby Denmark Institute for Automation and Applied Informatics Karlsruhe Institute of Technology 76344 Eggenstein-Leopoldshafen Germany Faculty of Engineering Port Said University Port Fuad 42526 Egypt Karlsruhe Nano Micro Facility Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany

This paper presents a concept for an integrated process chain for tooling production based on metal additive manufacturing. The proposed approach aims at taking advantage of a fully digitized production line, describing the main steps for the synergetic integration of the manufacturing assets. The production line entails digital infrastructure that collects and elaborate data from various monitoring sensors to execute corrective actions and continuously optimize the process. This line will bring breakthrough benefits, like flexibility and full traceability. Also challenges, as change management in the industry, skills gap, the requirement of new business models and product re-design have been addressed.

关键词： Smart manufacturing Industry 4.0 Additive Manufacturing automation Tooling

Modeling and Force Control of a Terramechanical Wheel-Soil Contact for a Robotic Manipulator Used in the Planetary Rover Design Process

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Modeling and Force Control of a Terramechanical Wheel-Soil C...

2019 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)

作者： Jan Wachter Ralf Mikut Fabian Buse Institute for Automation and Applied Informatics (IAI) Karlsruhe Institute of Technology Karlsruhe Germany German Aerospace Center (DLR) Institute of System Dynamics and Control Oberpfaffenhofen Germany

The German Aerospace Center (DLR) has developed the Terramechanics Robotics Locomotion Lab (TROLL) to provide a feasible testing facility for developing planetary exploration rovers, as well as validating terramechanical models. A robotic manipulator is used to provide the required degrees of freedom to the mounted wheel or subsystem, making it necessary to actively control the interaction force of the wheel-soil contact. This paper is concerned with the development of a feasible force control strategy for the testbench wheel-soil contact during single-wheel experiments. For this purpose, a terramechanical model has been developed to accurately map the dynamic processes relevant for the force control design, which is later used in a testbench simulation framework to predict and evaluate the performance of control strategies. The Adaptive Admittance Control (AAC) scheme developed is adapting the gain based on the current control deviation, the rotational velocity of the wheel and an estimated soil stiffness during the experiment. The AAC is evaluated using a benchmark single-wheel experiment and shows superior performance compared to standard admittance control.

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Towards Velocity Turnpikes in Optimal Control of Mechanical Systems ⁎

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IFAC-PapersOnLine 2019年第16期52卷 490-495页

作者： Timm Faulwasser Kathrin Flaßkamp Sina Ober-Blöbaum Karl Worthmann Institute for Automation and Applied Informatics Karlsruhe Institute of Technology (KIT) Germany University of Bremen Germany University of Oxford United Kingdom Institut für Mathematik Technische Universität Ilmenau Germany

The paper proposes first steps towards the formalization and characterization of time-varying turnpikes in optimal control of mechanical systems. We propose the concepts of velocity steady states, which can be considered as partial steady states, and hyperbolic velocity turnpike properties for analysis and control. We show for a specific example that, for all finite horizons, both the (essential part of the) optimal solution and the orbit of the time-varying turnpike correspond to (optimal) trim solutions. Hereby, the present paper appears to be the first to combine the concepts of trim primitives and time-varying turnpike properties.

关键词： Mechanical systems optimal control (partial) steady state velocity steady state turnpike property trim primitives symmetries

Semi-automatic generation of tight binary masks and non-convex isosurfaces for quantitative analysis of 3D biological samples

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arXiv 2020年

作者： Bhide, Sourabh Mikut, Ralf Leptin, Maria Stegmaier, Johannes Director’s Research Unit European Molecular Biology Laboratory Heidelberg Germany Collaboration for joint PhD degree between EMBL and Heidelberg University Faculty of Biosciences Institute for Automation and Applied Informatics Karlsruhe Institute of Technology Karlsruhe Germany European Molecular Biology Organization Heidelberg Germany Institute of Imaging and Computer Vision RWTH Aachen University Aachen Germany

Current in vivo microscopy allows us detailed spatiotemporal imaging (3D+t) of complete organisms and offers insights into their development on the cellular level. Even though the imaging speed and quality is steadily improving, fully-automated segmentation and analysis methods are often not accurate enough. This is particularly true while imaging large samples (100 µm −1 mm) and deep inside the specimen. Drosophila embryogenesis, widely used as a developmental paradigm, presents an example for such a challenge, especially where cell outlines need to imaged a general challenge in other systems as well. To deal with the current bottleneck in analyzing quantitatively the 3D+t light-sheet microscopy images of Drosophila embryos, we developed a collection of semi-automatic open-source tools. The presented methods include a semi-automatic masking procedure, automatic projection of non-convex 3D isosurfaces to 2D representations as well as cell segmentation and tracking. Copyright © 2020, The Authors. All rights reserved.

关键词： Biology

How to Teach Control System Optimization (A Practical Decompisition Approach for the Optimization of TDOF Control Systems)

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IFAC-PapersOnLine 2019年第9期52卷 115-120页

作者： Cs. Bányász L. Keviczky R. Bars Institute for Computer Science and Control of the Hungarian Academy of Sciences Department of Automation and Applied Informatics Budapest University of Technology and Economics H-1111 Budapest Kende u 13-17 Hungary

The optimality in a generic two-degree of freedom control system can be decomposed into three major steps, because the control error has three major parts: design-, realizability- and modeling-loss. The second term can be made zero for inverse stable processes only. This decomposition opens new ways for practical optimization of two-degree-of-freedom ( TDOF ) systems and helps the construction of new algorithms for robust identification and control. It is more reasonable to teach the optimization of control systems using these components.

关键词： two-degree-of-freedom control systems performance robustness optimality

Distributed state estimation for ac power systems using gauss-Newton aladin

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arXiv 2019年

作者： Du, Xu Engelmann, Alexander Jiang, Yuning Faulwasser, Timm Houska, Boris School of Information Science and Technology ShanghaiTech University Shanghai China Institute for Automation and Applied Informatics Karlsruhe Institue of Technology Eggenstein-Leopoldshafen Germany

This paper proposes a structure exploiting algorithm for solving non-convex power system state estimation problems in distributed fashion. Because the power flow equations in large electrical grid networks are non-convex equality constraints, we develop a tailored state estimator based on Augmented Lagrangian Alternating Direction Inexact Newton (ALADIN) method, which can handle the nonlinearities efficiently. Here, our focus is on using Gauss-Newton Hessian approximations within ALADIN in order to arrive at at an efficient (computationally and communicationally) variant of ALADIN for network maximum likelihood estimation problems. Analyzing an IEEE 30-Bus system we illustrate how the proposed algorithm can be used to solve highly nontrivial network state estimation problems. We also compare the method with existing distributed parameter estimation codes in order to illustrate its performance. Copyright © 2019, The Authors. All rights reserved.

关键词： Constrained optimization

Decreasing market value of variable renewables can be avoided by policy action

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arXiv 2020年

作者： Brown, T. Reichenberg, L. Berlin10587 Germany Institute for Automation and Applied Informatics Karlsruhe Institute of Technology Hermann-von-Helmholtz-Platz 1 Eggenstein-Leopoldshafen76344 Germany Department of Space Earth and Environment Chalmers University of Technology Göteborg412 96 Sweden Department of Mathematics and Systems Analysis Aalto University Otakaari 1 FEspoo Finland

Although recent studies have shown that electricity systems with shares of wind and solar above 80% can be affordable, economists have raised concerns about market integration. Correlated generation from variable renewable sources depresses market prices, which can cause wind and solar to cannibalise their own revenues and prevent them from covering their costs from the market. This cannibalisation appears to set limits on the integration of wind and solar, and thus to contradict studies that show that high shares are cost effective. Here we show from theory and with simulation examples how market incentives interact with prices, revenue and costs for renewable electricity systems. The decline in average revenue seen in some recent literature is due to an implicit policy assumption that technologies are forced into the system, whether it be with subsidies or quotas. This decline is mathematically guaranteed regardless of whether the subsidised technology is variable or not. If instead the driving policy is a carbon dioxide cap or tax, wind and solar shares can rise without cannibalising their own market revenue, even at penetrations of wind and solar above 80%. The strong dependence of market value on the policy regime means that market value needs to be used with caution as a measure of market integration. Declining market value is not necessarily a sign of integration problems, but rather a result of policy choices. Copyright © 2020, The Authors. All rights reserved.

关键词： Carbon dioxide

On the application of the semismooth* Newton method to variational inequalities of the second kind

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arXiv 2020年

作者： Gfrerer, Helmut Outrata, Jiří V. Valdman, Jan Institute of Computational Mathematics Johannes Kepler University Linz LinzA-4040 Austria Institute of Information Theory and Automation Czech Academy of Sciences Prague18208 Czech Republic Centre for Informatics and Applied Optimization Federation University of Australia POB 663 BallaratVic3350 Australia Institute of Mathematics Faculty of Science University of South Bohemia České Budějovice37005 Czech Republic

The paper starts with a concise description of the recently developed semismooth* Newton method for the solution of general inclusions. This method is then applied to a class of variational inequalities of the second kind. As a result, one obtains an implementable algorithm exhibiting a local superlinear convergence. Thereafter we suggest several globally convergent hybrid algorithms in which one combines the semismooth* Newton method with selected splitting algorithms for the solution of monotone variational inequalities. Their efficiency is documented by extensive numerical *** Codes 65K10, 65K15, 90C33. Copyright © 2020, The Authors. All rights reserved.

关键词： Variational techniques

Imitation modeling of radiation of ultra short pulses by Horn antenna and evaluation of the energy efficiency of radiators on their basis

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Imitation modeling of radiation of ultra short pulses by Hor...

IEEE International Symposium on Electromagnetic Compatibility - EMC Europe

作者： A. S. Usychenko L. N. Sorokin A. A. Sasunkevich Yu. M. Kutsan Laboratory of Applied Informatics and Problems of Information Society St. Petersburg Institute for Informatics and Automation of the Russian Academy of Science (SPIIRAS) St. Petersburg Russia Federal budgetary military educational institution of higher education "Military space Academy named after A.F. Mozhaysky" of the Ministry of defense of the Russian Federation St. Petersburg Russia Joint Stock Company "Scientific Research Institute "Vector" St. Petersburg Russia

ISBN: (数字)9781728155791

ISBN: (纸本)9781728155807

Software has been developed for automating the process of modeling ultrashort pulse radiation by broadband horn antennas. The influence of the duration of unipolar and bipolar voltage pulses exciting the antennas on the energy efficiency of their radiation is studied. It has been established that for each radiating antenna, regardless of the shape of the excitation pulse, there is approximately the same duration for which the maximum energy is radiated into space. It is shown that for equal energies of voltage pulses exciting antennas, the energy efficiency of radiation of bipolar pulses is higher than that of unipolar pulses.

关键词： Shape Horn antennas Electromagnetic compatibility Energy efficiency Ultra wideband antennas Software Antenna radiation patterns

The size of the friction coefficient of the sliding pair depending on the lubricant used

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Materials Science Forum 2018年 919卷 327-334页

作者： Labašová, Eva Labaš, Vladimír Slovak University of Technology Faculty of Materials Science and technology Institute of Applied Informatics Automation and Mechatronics Bottova 25 Slovakia Slovak University of Technology Faculty of Materials Science and technology Institute of Materials Science Bottova 25 Slovakia

Tribometry methods are focused on the research of tribological processes. These method also include model tests on experimental equipment, which operate in exactly-defined mode. Input parameters of tests are transparent and easy to maintain constant. Outputs variables, which are recorded, represent characteristic parameters of tribological processes. Tests are carried out on simple test samples. The aim of these methods is to numerically express the magnitude of friction force, friction moment, respectively determinate the friction coefficient. The contribution is focused on determining the friction coefficient for brass and steel test samples. The measurements were realized on a test machine Tribotestor M`89. Size of the sliding velocity and size of the loading force were entered to the tests as input parameters. Two types of oil were used in the experiments: Castrol Manual EP 80W and Madit PP90. The results obtained show that the friction coefficient value decreases with the increasing normal load for both materials and also for both lubricants. Smaller friction coefficient values were achieved using lubricant Castrol manual EP 80W for both materials. The average values of the friction coefficient under the load conditions ranged from 0.056 to 0.1240. © 2018 Trans Tech Publications, Switzerland.

关键词： Brass