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Bramerdorfer G.,Johannes Kepler University | Andessner D.,Linz Center of Mechatronics
IEEE Transactions on Industrial Electronics | Year: 2017

Iron loss modeling is crucial for electric machine design. However, current models feature severe drawbacks. They are 1) very complex, and thus, can hardly be applied, 2) require very high effort for measuring and computation, and/or 3) are not very accurate. In this paper, a new modeling technique is introduced for calculating the instantaneous power loss in ferromagnetic materials without taking the magnetization history into account. A standard measurement setup and specimen shape is used. The considered approach comprises the required measurements, the nonlinear loss modeling by itself, and an extensive verification for different flux density waveforms and frequencies. In addition, a detailed qualitative comparison to well-known iron loss models is given. The presented technique gives very accurate results, while obtaining the model is comparably easy. Moreover, as the calculation of the instantaneous losses is not based on the previous magnetization state of the material, a modeling error for a particular instant of time has no impact on the subsequently calculated characteristics. In the future, this model should ensure a more accurate iron loss calculation for electric machine designs. © 2016 IEEE.

Agency: European Commission | Branch: H2020 | Program: ECSEL-IA | Phase: ECSEL-17-2015 | Award Amount: 64.82M | Year: 2016

ENABLE-S3 will pave the way for accelerated application of highly automated and autonomous systems in the mobility domains automotive, aerospace, rail and maritime as well as in the health care domain. Virtual testing, verification and coverage-oriented test selection methods will enable validation with reasonable efforts. The resulting validation framework will ensure Europeans Industry competitiveness in the global race of automated systems with an expected market potential of 60B in 2025. Project results will be used to propose standardized validation procedures for highly automated systems (ACPS). The technical objectives addressed are: 1. Provision of a test and validation framework that proves the functionality, safety and security of ACPS with at least 50% less test effort than required in classical testing. 2. Promotion of a new technique for testing of automated systems with physical sensor signal stimuli generators, which will be demonstrated for at least 3 physical stimuli generators. 3. Raising significantly the level of dependability of automated systems due to provision of a holistic test and validation platform and systematic coverage measures, which will reduce the probability of malfunction behavior of automated systems to 10E-9/h. 4. Provision of a validation environment for rapid re-qualification, which will allow reuse of validation scenarios in at least 3 development stages. 5. Establish open standards to speed up the adoption of the new validation tools and methods for ACPS. 6. Enabling safe, secure and functional ACPS across domains. 7. Creation of an eco-system for the validation and verification of automated systems in the European industry. ENABLE-S3 is strongly industry-driven. Realistic and relevant industrial use-cases from smart mobility and smart health will define the requirements to be addressed and assess the benefits of the technological progress.

Agency: European Commission | Branch: H2020 | Program: RIA | Phase: ICT-10-2015 | Award Amount: 2.36M | Year: 2016

Political consumerism is a bottom up, grass root engagement of concerned citizens. By uniting their individual selves to a collective, the feeling of individual insignificance is transformed into a non-negligible player on the economic market. The diversification of political interests, the intransparent product interrelationships, however, far too often lead to an evaporation of the collective motion, of the rising up of individually aware citizens. The ASSET project develops and tests a pilot solution to pioneer on a new form of political consumerism aiming at empowering the individual to facilitate and to reinforce sustainable consumerism, through better decision-making and networking effects. Leveraging on the innovative combinations of interests by distilling individual and amplifying collective interests and forming collective political consumerism, it serves as an empowerment for the citizen. This crowd-sourced political consumerism builds upon open data, open source, distributed social networking and open hardware. Seizing the full potential of existing mobile communication, it creates collective awareness for political concerns amongst citizens, via integrating network and online collaboration, and collective awareness on economical demands for producers, visualizing mutual interest for sustainable consumption. The pilot solution includes an individually designed product rating system which is seamlessly integrated into the shopping routines. The pilot solution is developed by a multidisciplinary consortium including retail industry, consumer organization, social sciences and ICT centers, and is tested in fields studies with existing communities of people.

Agency: European Commission | Branch: FP7 | Program: MC-IAPP | Phase: FP7-PEOPLE-2009-IAPP | Award Amount: 299.95K | Year: 2010

The proposed research focuses on the advanced development and implementation of a magnetically levitated high speed motor system for industrial spinning machines. The goal of the proposed project is to realise a novel and worldwide unique rotor spinning concept with superior yarn quality by the use of active magnetic bearings in combination with a high efficiency brushless direct current (BLDC) motor. The rotor spinning technology has proven to be the emerging trend in industrial spinning due to the advantages in maintenance and higher productivity. Therefore, the project aims to address the needs of tomorrows rotor spinning machines based on a multidisciplinary mechatronic approach by combining magnetic suspended motor technology with spinning technology. The Institute of Electrical Drives and Power Electronics of the Johannes Kepler University (JKU) will coordinate the research work and give its competence in magnetic bearing technology and electrical drives. Rieter CZ will contribute the knowledge in development of spinning machines and spinning technology and the Linz Center of Mechatronics (LCM) GmbH will add its experience in power electronics.

Irschik H.,Johannes Kepler University | Gerstmayr J.,Linz Center of Mechatronics
Mathematical and Computer Modelling of Dynamical Systems | Year: 2011

This article deals with the non-linear modelling of beams that are bent, sheared and stretched by external forces and moments. In the following, we restrict to planedeformations and static conditions. Our task is to present a continuum mechanicsbased interpretation of the celebrated large displacement finite deformation structural mechanics theory, which was presented by Eric Reissner [On one-dimensional finitestrain beam theory: the plane problem, J. Appl. Math. Phys. 23 (1972), pp. 795-804]. The latter formulation was restricted to the notions of structural mechanics and thus did not use the notions of stress and strain, which are fundamental for continuum mechanics. Thus, the common continuum mechanics-based constitutive modelling at the stress-strain level cannot be utilized in connection with Reissner's original theory. Instead, Reissner suggested that constitutive relations between certain generalized strains (bending, shear and axial force strains) and generalized static entities (bending moments, shear and normal forces) should be evaluated from physical experiments. This means that the beam to be studied must be first built up, and the experiments must be performed for the real beam as a whole. Although such physical experiments are indeed to be performed in practice for safety reasons in sensible cases, for example, bridge decks or aircraft wings, it is nevertheless felt to be a drawback that the results of simple standardized stress-strain experiments concerning the constitutive behaviour of the materials, from which the beam is built up, cannot be used. Moreover, relying only on physical experiments on the whole beam means that computations (virtual experiments) can be made only after the beam has been built up. To overcome this problem, we subsequently present a continuum mechanics-based interpretation of Reissner's structural mechanics modelling, by attaching a proper continuum mechanics-based meaning to both the generalized static entities and the generalized strains in Reissner's theory [E. Reissner, On one-dimensional finite-strain beam theory: the plane problem, J. Appl. Math. Phys. 23 (1972), pp. 795-804]. Consequently, these generalized static entities can be related to the generalized strains on the basis of a constitutive modelling on the stress-strain level. We show this in some detail in this contribution for a hyperelastic material proposed by Simo and Hughes [Computational Inelasticity, Springer, New York, 1998]. An illustrative numerical example is given which shows the results of large bending and axial deformation behaviour for different constitutive relations. This article represents an extended version of a preliminary work published in [H. Irschik and J. Gerstmayr, A hyperelastic Reissner-type model for non-linear shear deformable beams, Proceedings of the Mathmod 09 Vienna, I. Troch and F. Breitenecker, eds., 2009, pp. 1-7]. © 2011 Taylor & Francis.

Zehetner C.,Linz Center of Mechatronics | Krommer M.,Johannes Kepler University
Structural Control and Health Monitoring | Year: 2012

This paper is concerned with active control of torsional vibrations in laminated rods by piezoelectric shear sensors and actuators. A piezoelectric layer can be used as a sensor by utilizing the direct piezoelectric effect, measuring either the charge on short-circuited electrodes or the voltage on open electrodes. On the other hand, the converse piezoelectric effect enables actuation by applying an electric potential difference to the electrodes of a piezoelectric layer. The sensor and actuator equations are formulated in the framework of an extended Saint-Venant torsion theory considering additional cross-sectional warping due to piezoelectric eigenstrains. A solution of the shape control problem for torsional vibrations is presented, i.e. the necessary distribution of actuation strains in order to completely compensate vibrations caused by external excitations. For the case, in which the external excitations are not known exactly, a feedback control solution is presented using one piezoelectric layer as a sensor and a second one as an actuator. For the examples of a rectangular and a circular cross-section, the theoretical results are validated by three-dimensional finite element computations, showing a very good coincidence. Copyright © 2011 John Wiley & Sons, Ltd.

Mitterhofer H.,Austrian Center of Competence in Mechatronics | Mitterhofer H.,Linz Center of Mechatronics | Gruber W.,Austrian Center of Competence in Mechatronics | Amrhein W.,Austrian Center of Competence in Mechatronics
IEEE Transactions on Industrial Electronics | Year: 2014

With soaring raw material costs, the need for smaller drives running at higher speeds is ever increasing. In parallel, magnetic bearings and bearingless drives have outgrown the purely academic level and are the state of the art solution for several industrial processes. All the bearingless drives in industry and most of them in academic research run at relatively low speeds of up to 15 000 r/min. Thus, the suitability for high speed operation remained unclear. Along with a brief introduction to bearingless drives, the criteria for high speed operation and the ability of this topology to fulfill them is discussed in the first part. The second part gives a description of a prototype system, designed to reach speeds of beyond 100 000 r/min. The last section shows the experimental results of the prototype concerning the operational behavior. © 1982-2012 IEEE.

Vetyukov Y.,Linz Center of Mechatronics
Acta Mechanica | Year: 2012

A multi-stage approach for the mathematical modeling in the field of nonlinear problems of mechanics of thin-walled structures is the subject of the present paper. A combination of the asymptotic, direct, and numerical methods for consistent and efficient analysis of problems of structural mechanics is presented on the example of plane problem of finite vibrations of a thin curved strip with material inhomogeneity. The method of asymptotic splitting allows for a consistent dimensional reduction of the original two-dimensional continuous problem as the thickness is small: the leading-order solution of the full system of equations of the theory of elasticity results in a one-dimensional formulation of the reduced theory and a problem in the cross-section. The direct approach to a material line extends the results to the geometrically nonlinear range. The appropriate finite element formulation allows for practical applications of the theory; with the numerical solution of the reduced problem, we restore the distributions of stresses, strains, and displacements over the thickness. Numerically and analytically investigated convergence of the solutions of various problems in the original (two-dimensional) and reduced (one-dimensional) models as the thickness tends to zero justifies the analytical conclusion that the curvature and variation of the material properties over the thickness do not require special treatment for classical Kirchhoff's rods. Further terms of the asymptotic expansion lead to a model with shear and extension, in which curvature appears in a nontrivial way. © Springer-Verlag 2011.

Potsch A.,Linz Center of Mechatronics
2016 15th ACM/IEEE International Conference on Information Processing in Sensor Networks, IPSN 2016 - Proceedings | Year: 2016

At least since the terms Internet of Things, Factories of the Future or Industrial Internet gave distinction to the modern world of communication, there is a special need for efficient test- and debug tools targeting research and development of embedded wireless sensor and actuator networks (WSAN) in industrial automation technology and other non-consumer application areas in adverse environments. Those networks usually have tighter requirements on dependability, synchronization, and real-time capability as compared applications in environmental monitoring or home automation. For WSAN research and development, testbeds are a valuable tool as they enable controlled and repeatable operation under conditions close to reality. The contribution of this Ph.D. dissertation is to design, implement and set up a test environment for embedded industrial wireless sensor actuator networks, with special focus on energy constrained network nodes. This testbed should offer an previously unattained level of insight in timing characteristics of the network and the energy behavior of a single node. It allows to make statements about limitations of the deployed WSAN technology, or to compare different WSAN solutions in an automated manner. The uniqueness of this testbed setup is due to a scalable, affordable and maintainable organization both in software as well as the structure of the used hardware components. © 2016 IEEE.

A hydraulic drive carries out a method for discretely changing a positional output on the hydraulic drive. At least one displacement cylinder incrementally supplies or discharges the cylinder volume to or from the drive by displacing the cylinder piston element from a starting to an end position depending on at least one input signal. The piston element is repeatedly displaced from starting to end position and back to discretely change the positional output correspondingly to the supplied or discharged displacement volume. The cylinder is hydraulically connected to a pressure medium source supply or return line while displacing the piston element from starting to end position. The changed positional output is restored in a successive step. The cylinder chambers of the displacement cylinder are hydraulically short-circuited by a short-circuit line hydraulically separated from the supply or return line when returning the piston element from the end to the starting position.

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