@article{9860,
  abstract     = {{Self-optimizing mechatronic systems offer possibilities well beyond those of traditional mechatronic systems. Among these is the adaptation of the system behavior to the current situation. To do so, they are able to choose from different working points, which are pre-calculated using multiobjective optimization and are thus Pareto-optimal with regard to the chosen objective functions. In this contribution, a method is presented that allows to continuously control the system degradation by adapting the behavior of a selfoptimizing system throughout its complete lifetime. The current remaining useful lifetime is estimated and then related to the spent lifetime and the desired useful lifetime. Using this information, a reliability-related objective is prioritized using a closed-loop control, which in turn is used to determine the working point of the self-optimizing system. This way, the desired useful lifetime can be achieved. To exemplify the setup of the controller structure and to demonstrate the adaptation of the system behavior, a dynamic model of a clutch system is used. It can be seen that the closed loop controller is able to correct for external perturbations, such as changed requirements, as well as changed system parameters. This way, the modeled system is able to achieve the desired lifetime reliably.}},
  author       = {{Meyer, Tobias and Sondermann-Wölke, Christoph and Kimotho, James Kuria and Sextro, Walter}},
  journal      = {{Chemical Engineering Transactions}},
  pages        = {{625--630}},
  title        = {{{Controlling the Remaining Useful Lifetime using Self-Optimization}}},
  doi          = {{10.3303/CET1333105}},
  volume       = {{33}},
  year         = {{2013}},
}

@inproceedings{9861,
  abstract     = {{Selbstoptimierende mechatronische Systeme bieten die Möglichkeit, ihr Verhalten an geänderte Umgebungsbedingungen anzupassen. Dazu werden beispielsweise redundante Strukturen genutzt, Reglerparameter angepasst oder Regelstrategien umgeschaltet. Dies kann auch genutzt werden, um die Zuverlässigkeit des Systems zu steigern. Zugleich entstehen aber durch die gesteigerte Komplexität dieser Systeme zusätzliche Risiken. Um sicherzustellen, dass das System dennoch die gestellten Anforderungen bezüglich der Zuverlässigkeit erfüllt, ist eine Modellierung des Gesamtsystems und anschließende Zuverlässigkeitsbewertung notwendig. Dies ist aufgrund der situationsabhängigen Verhaltensanpassung und des nicht intuitiv vorhersehbaren Verhaltens jedoch nicht mit klassischen Verfahren möglich. Ein Modellierungsverfahren, das diese Eigenschaften abbilden kann, ist LARES (LAnguage for REconfigurable dependable Systems). Die Anwendung von LARES zur Bewertung der Zuverlässigkeit eines selbstoptimierenden Systems wird anhand des Feder-Neige-Moduls gezeigt. Es ist eine Baugruppe der Fahrzeuge eines innovativen Bahnsystems, der RailCabs. Das Feder-Neige-Modul dient dazu, unerwünschte Schwingungen des Fahrzeugaufbaus zu minimieren. Mit LARES können die Hardware-Komponenten des Systems, ihre in Abhängigkeit von der aktuellen Situation veränderten Belastungen sowie die nicht-deterministische Verhaltensadaption modelliert werden.}},
  author       = {{Meyer, Tobias and Sondermann-Wölke, Christoph and Sextro, Walter and Riedl, Martin and Gouberman, Alexander and Siegle, Markus}},
  booktitle    = {{9. Paderborner Workshop Entwurf mechatronischer Systeme}},
  editor       = {{Gausemeier, Jürgen and Dumitrescu, Roman and Rammig, Franz and Schäfer, Wilhelm and Trächtler, Ansgar}},
  pages        = {{161--174}},
  publisher    = {{Heinz Nixdorf Institut, Universität Paderborn}},
  title        = {{{Bewertung der Zuverlässigkeit selbstoptimierender Systeme mit dem LARES-Framework}}},
  year         = {{2013}},
}

@article{9781,
  abstract     = {{A piezoelectric energy harvester is an electromechanical device that converts ambient mechanical vibration into electric power. Most existing vibration energy harvesting devices operate effectively at a single frequency only, dictated by the design of the device. This frequency must match the frequency of the host structure vibration. However, real world structural vibrations rarely have a specific constant frequency. Therefore, piezoelectric harvesters that generate usable power across a range of exciting frequencies are required to make this technology commercially viable. Currently known harvester tuning techniques have many limitations, in particular they miss the ability to work during harvester operation and most often cannot perform a precise tuning. This paper describes the design and testing of a vibration energy harvester with tunable resonance frequency, wherein the tuning is accomplished by changing the attraction force between two permanent magnets by adjusting the distance between the magnets. This tuning technique allows the natural frequency to be manipulated before and during operation of the harvester. Furthermore the paper presents a physical description of the frequency tuning effect. The experimental results achieved with a piezoelectric bimorph fit the calculated results very well. The calculation and experimental results show that using this tuning technique the natural frequency of the harvester can be varied efficiently within a wide range: in the test setup, the natural frequency of the piezoelectric bimorph could be increased by more than 70\%.}},
  author       = {{Al-Ashtari, Waleed and Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}},
  journal      = {{Smart Materials and Structures}},
  number       = {{3}},
  pages        = {{035019}},
  title        = {{{Frequency tuning of piezoelectric energy harvesters by magnetic force}}},
  volume       = {{21}},
  year         = {{2012}},
}

@article{9782,
  abstract     = {{Piezoelectric structures are nowadays used in many different applications. A better understanding of the influence of material properties and geometrical design on the performance of these structures helps to develop piezoelectric structures specifically designed for their application. Different equivalent circuits have been introduced in the literature to investigate the behaviour of piezoelectric transducers. The model parameters are usually determined from measurements covering the characteristic frequencies of the piezoelectric transducer. This article introduces an analytical technique for calculating the mechanical and electrical equivalent system parameters and characteristic frequencies based on material properties and geometry for a cantilever bimorph structure. The model is validated by measurements using a cantilever bimorph and fits the experimental results better than previous models. The model gives a full set of piezoelectric transducer parameters and is therefore well suited for further theoretical investigations of piezoelectric transducers for different applications. The results also show that even small manufacturing tolerances have a considerable effect on the system parameters and characteristic frequencies. This might lead to intolerable deviations, especially in dynamic applications and should be avoided by careful design and production.}},
  author       = {{Al-Ashtari, Waleed and Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}},
  journal      = {{Journal of Intelligent Material Systems and Structures}},
  number       = {{1}},
  pages        = {{15--23}},
  title        = {{{Analytical determination of characteristic frequencies and equivalent circuit parameters of a piezoelectric bimorph}}},
  doi          = {{10.1177/1045389X11430742}},
  volume       = {{23}},
  year         = {{2012}},
}

@inproceedings{9783,
  abstract     = {{To optimize the ultrasound irradiation for cavitation based ultrasound applications like sonochemistry or ultrasound cleaning, the correlation between cavitation intensity and the resulting effect on the process is of interest. Furthermore, changing conditions like temperature and pressure result in varying acoustic properties of the liquid. That might necessitate an adaption of the ultrasound irradiation. To detect such changes during operation, process monitoring is desired. Labor intensive processes, that might be carried out for several hours, also require process monitoring to increase their reliability by detection of changes or malfunctions during operation. In some applications cavitation detection and monitoring can be achieved by the application of sensors in the sound field. Though the application of sensors is possible, this necessitates modifications on the system and the sensor might disturb the sound field. In other applications harsh, process conditions prohibit the application of sensors in the sound field. Therefore alternative techniques for cavitation detection and monitoring are desired. The applicability of an external microphone and a self-sensing ultrasound transducer for cavitation detection were experimentally investigated. Both methods were found to be suitable and easily applicable.}},
  author       = {{Bornmann, Peter and Hemsel, Tobias and Sextro, Walter and Maeda, Takafumi and Morita, Takeshi}},
  booktitle    = {{Ultrasonics Symposium (IUS), 2012 IEEE International}},
  issn         = {{1948-5719}},
  keywords     = {{cavitation, chemical reactors, microphones, process monitoring, reliability, ultrasonic applications, ultrasonic waves, acoustic properties, cavitation based ultrasound applications, cavitation intensity, change detection reliability, external microphone, malfunction detection reliability, nonperturbing cavitation detection, nonperturbing cavitation monitoring, process monitoring, self-sensing ultrasound transducer, sonochemical reactors, sonochemistry, ultrasound cleaning, ultrasound irradiation, Acoustics, Liquids, Monitoring, Sensors, Sonar equipment, Transducers, Ultrasonic imaging}},
  pages        = {{1141--1144}},
  title        = {{{Non-perturbing cavitation detection / monitoring in sonochemical reactors}}},
  doi          = {{10.1109/ULTSYM.2012.0284}},
  year         = {{2012}},
}

@inproceedings{9787,
  author       = {{Kohl, Sergej and Sextro, Walter and Zuber, Armin}},
  booktitle    = {{8. Tag des Fahrwerks, Aachen, 2012}},
  pages        = {{38--60}},
  title        = {{{Benteler Vehicle Dynamics -- Fahrdynamikentwicklung basierend auf einer neuen Auslegungstheorie}}},
  year         = {{2012}},
}

@inproceedings{9791,
  abstract     = {{The rapid development of communication and information technology opens up fascinating perspectives, which go far beyond the state of the art in mechatronics: mechatronic systems with inherent partial intelligence. These so called self-optimizing systems adapt their objectives and behavior autonomously and flexibly to changing operating conditions. On the one hand, securing the dependability of such systems is challenging due to their complexity and non-deterministic behavior. On the other hand, self-optimization can be used to increase the dependability of the system during its operation. However, it has to be ensured, that the self-optimization works dependable itself. To cope with these challenges, the multi-level dependability concept was developed. It enables predictive condition monitoring, influences the objectives of the system and determines suitable means to improve the system's dependability during its operation. In this contribution we introduce a procedure for the conceptual design of an advanced condition monitoring based on the system's principle solution. The principle solution describes the principal operation mode of the system and its desired behavior. It is modeled using the specification technique for the domain-spanning description of the principle solution of a self-optimizing system and consists of a coherent system of eight partial models (e.g. requirements, active structure, system of objectives, behavior, etc.). The partial models are analyzed separately in order to derive the components of the multi-level dependability concept. In particular, the reliability analysis of the partial model active structure is performed to identify the system elements to be monitored and parameters to be measured. The principle solution is extended accordingly: e.g. with system elements required for the realization of the dependability concept. The advantages of the method are shown on the self-optimizing guidance module of a railroad vehicle.}},
  author       = {{Sondermann-Wölke , Christoph and Meyer, Tobias and Dorociak, Rafal and Gausemeier, Jürgen and Sextro, Walter}},
  booktitle    = {{Proceedings of the 11th International Probabilistic Safety Assessment and Management Conference (PSAM11) and The Annual European Safety and Reliability Conference (ESREL2012)}},
  keywords     = {{Mechatronic Systems, Principle Solution, Condition Monitoring, Conceptual Design}},
  title        = {{{Conceptual Design of Advanced Condition Monitoring for a Self-Optimizing System based on its Principle Solution}}},
  year         = {{2012}},
}

@article{9806,
  abstract     = {{Piezoelectric inertia motors, also known as ``stick-slip-drives'', use the inertia of a body to drive it by means of a friction contact in small steps. While these steps normally involve stiction and sliding, the motors can also operate in ``slip-slip'' mode without any phase of static friction. In this contribution, a one degree of freedom model of an inertia motor driven by an ideal actuator is analysed. Start-up and constant velocity operation of the motor are investigated and appropriate quantities to compare ``stick-slip'' and ``slip-slip'' operation are determined. Different aspects such as velocity, uniformity of motion, load capacity, robustness, efficiency, and wear are considered. The analysis allows both modes to be applied advantageously in different applications and can widen the field of application of piezoelectric inertia motors. Motor designers are enabled to choose the appropriate mode of operation and the best drive parameters for their individual applications.}},
  author       = {{Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}},
  journal      = {{ACTUATOR 2012 Conference Proceedings}},
  keywords     = {{Piezoelectric Inertia Motors, Drive Signals, Stick-slip, Slip-slip}},
  pages        = {{761--764}},
  title        = {{{Analysis of different operation modes for inertia motors}}},
  year         = {{2012}},
}

@inproceedings{26981,
  author       = {{Sondermann-Wölke, Christoph and Sextro, Walter and Reinold, Peter and Trächtler, Ansgar}},
  booktitle    = {{Technische Zuverlässigkeit TTZ}},
  title        = {{{Zuverlässigkeitsorientierte Mehrzieloptimierung zur Aktorrekonfiguration eines X-by-wire-Fahrzeugs}}},
  year         = {{2011}},
}

@inproceedings{23184,
  author       = {{Lurye, Oleg and Sondermann-Wölke, Christoph and Kromov, Ivan and Sextro, Walter and Trächtler, Ansgar}},
  booktitle    = {{VDI Bericht zur Tagung Technische Zuverlässigkeit}},
  publisher    = {{VDI-Verlag}},
  title        = {{{Verlässlichkeitsanalyse des Degradationsverhaltens mechatronischer Systeme mit mehreren Betriebsstrategien}}},
  year         = {{2011}},
}

@inproceedings{23194,
  author       = {{Sondermann-Wölke, Christoph and Sextro, Walter and Reinold, Peter and Trächtler, Ansgar}},
  booktitle    = {{Technische Zuverlässigkeit TTZ}},
  title        = {{{Zuverlässigkeitsorientierte Mehrzieloptimierung zur Aktorrekonfiguration eines X-by-wire-Fahrzeugs}}},
  year         = {{2011}},
}

@inproceedings{9768,
  author       = {{Lurie, Oleg and Kromov, Ivan and Trächtler, Ansgar and Sondermann-Wölke, Christoph and Sextro, Walter}},
  booktitle    = {{25. Tagung Technische Zuverlässigkeit (TTZ 2011) - Entwicklung und Betrieb zuverlässiger Produkte}},
  pages        = {{99--110}},
  title        = {{{Dependability Analysis of the Degradation Behavior of Mechatronics Systems with Different Operating Strategies}}},
  year         = {{2011}},
}

@inproceedings{9771,
  abstract     = {{Dieser Beitrag stellt ein Konzept vor, welches die Methode der Mehrzieloptimierung mit einer Online-Bewertung des aktuellen Systemzustands kombiniert. Dieses erlaubt Maßnahmen zur Zuverlässigkeitssteigerung abzuleiten. Das Konzept wird auf ein X-by-wire-Fahrzeug mit Einzelradaktorik angewandt. Dabei steht zunächst die Beeinflussung der Ziele der Mehrzieloptimierung zugunsten der Zuverlässigkeit des Systems im Vordergrund. In Simulationen wird gezeigt, dass über die Wahl und Gewichtung der Zielfunktionen die Quer- und Längskräfte an den Rädern vorteilhaft verteilt werden können. 

In this contribution a concept is illustrated, which combines the multi-objective optimization technique with an online assessment of the current system state. This allows deriving measures to increase the reliability of the system. The concept is applied to an X-by-wire vehicle with single-wheel actuators. The emphasis is here mostly on the influence of the objectives of the multiobjective optimization for the benefit of the reliability of the system. It is demonstrated in simulations, that the lateral and longitudinal forces at the wheels can be distributed advantageously by the selection of the suitable objective functions and the appropriate weights.}},
  author       = {{Sondermann-Wölke, Christoph and Sextro, Walter and Reinold, Peter and Trächtler, Ansgar}},
  booktitle    = {{25. Tagung Technische Zuverlässigkeit (TTZ 2011) - Entwicklung und Betrieb zuverlässiger Produkte}},
  pages        = {{291--302}},
  title        = {{{Zuverlässigkeitsorientierte Mehrzieloptimierung zur Aktorrekonfiguration eines X-by-wire-Fahrzeugs}}},
  year         = {{2011}},
}

@article{9772,
  abstract     = {{A profound description of friction in wheel--rail contact plays an essential role for optimization of traction control strategies, as input quantity for railway simulations in general and for the estimation of wear and rolling contact fatigue. A multitude of wheel--rail contact models exists, however, traction--creepage curves obtained from measurements show quantitative and qualitative deviations. There are several phenomena which influence the traction--creepage characteristics: Mechanisms resulting from surface roughness, frictional heating or the presence of interfacial fluids can have a dominating influence on friction. In this paper, a new wheel--rail contact model, accounting for these influential parameters, will be presented. The presented model accounts for the interaction of an interfacial fluid model for combined boundary and mixed lubrication of rough surfaces with a wheel--rail contact model that additionally accounts for frictional heating. A quantitative comparison with measurements found in the literature is not conducted, since the exact conditions of the measurements are mostly unknown and parameters can easily be adjusted to fit the measurements. Emphasis is placed on the qualitative behavior of the model with respect to the measurements and good agreement is found. The dependence of the maximum traction coefficient on rolling velocity, surface roughness and normal load is studied under dry and water lubricated conditions.}},
  author       = {{Tomberger, Christoph and Dietmaier, Peter and Sextro, Walter and Six, Klaus}},
  issn         = {{0043-1648}},
  journal      = {{Wear}},
  keywords     = {{Wheel--rail contact, Rolling contact, Friction, Interfacial fluid, Lubrication, Surface roughness, Contact temperature}},
  pages        = {{2 -- 12}},
  title        = {{{Friction in wheel--rail contact: A model comprising interfacial fluids, surface roughness and temperature}}},
  doi          = {{10.1016/j.wear.2010.10.025}},
  volume       = {{271}},
  year         = {{2011}},
}

@misc{9790,
  abstract     = {{Es wird eine Anordnung zur mehrdimensionalen Messung von Schwingungen eines Objektes vorgeschlagen, umfassend ein Vibrometer und eine erste Ablenkeinheit, mittels welcher der Messstrahl des Vibrometers in wenigstens zwei erste Raumrichtungen ablenkbar ist, sowie wenigstens eine zweite Ablenkeinheit, mittels welcher der aus einer der wenigstens zwei ersten Raumrichtungen auf eine zweite Ablenkeinheit eintreffende Messstrahl derart ablenkbar ist, dass ein Messpunkt des Objekts aus einer ersten Raumrichtung und wenigstens einer zweiten Raumrichtung oder wenigstens zwei zweiten Raumrichtungen damit erfassbar ist. Bei dem zum Betrieb der Anordnung vorgesehenen Verfahren wird der Messstrahl eines Vibrometers in wenigstens zwei erste Raumrichtungen abgelenkt, woraufhin wenigstens ein Messstrahl einer ersten Raumrichtung ein zweites Mal derart abgelenkt wird, dass ein Messpunkt des Objekts aus einer ersten Raumrichtung und wenigstens einer zweiten Raumrichtung oder wenigstens zwei zweiten Raumrichtungen erfasst wird, insbesondere so dass die zu untersuchenden Bewegungskomponenten in den Messsignalen, welche entlang der ersten und zweiten Raumrichtungen gewonnen werden, enthalten sind. The arrangement has a first deflecting unit (3) for deflecting a measuring beam of a vibrometer (2) in spatial directions (4-6, 4-6). Second and third deflecting units (7, 8) deflect the beam arriving from one of the spatial directions such that a measuring point (9) of an object (1) is detectable with the beam from the spatial direction or the spatial directions. The first deflecting unit is designed as a scanning unit, where the measuring point is detected by the scanning unit. A measuring instrument measures focus quality and is connected to actuators for adjustment of the focus quality. An independent claim is also included for a method for multidimensional measurement of oscillations of an object.}},
  author       = {{Sextro, Walter and Hunstig, Matthias and Bornmann, Peter and Hemsel, Tobias}},
  title        = {{{Patent DE10201003395: Anordnung und Verfahren zur mehrdimensionalen Messung von Schwingungen eines Objekts. }}},
  year         = {{2011}},
}

@article{9747,
  abstract     = {{Bei der Konstruktion von Maschinen ist es oftmals erforderlich, Schwingungen minimal zu halten. Um z.B. die Lebensdauer zu erhöhen, Material einzusparen oder den Geräuschpegel gering zu halten muss oft ein großer Aufwand zur Dämpfung von auftretenden Schwingungen betrieben werden. In vielen technischen Anwendungen werden Einzelteile miteinander verschraubt. Diese Fügestellen können gezielt und mit wenig Aufwand zur Schwingungsdämpfung herangezogen werden. Die Berechnung des dynamischen Verhaltens verschraubter Strukturen stellt immer noch eine Herausforderung dar. Es wurde eine Methode entwickelt, um den eingeschwungenen Zustand elastischer, miteinander verschraubter Körper mit rauen Fügestellen bei periodischer Anregung zu berechnen. Als Basis dienen Finite Elemente Modelle der einzelnen Teile, deren Freiheitsgrade durch modale Kondensation reduziert werden. Unter Anwendung des Verfahrens von Ritz und Galerkin wird eine Näherungslösung für den eingeschwungenen Zustand des nichtlinearen, gekoppelten Systems ermittelt. Abhängig von den Schraubenvorspannkräften sowie den bestimmenden Parametern der Kontaktflächen, Rautiefe und Reibungskoeffizient, kann die Systemantwort berechnet und optimiert werden. Um die Berechnungsmethode zu verifizieren wurden Experimente durchgeführt. Der Vergleich zwischen Messung und Rechnung zeigt eine gute Übereinstimmung. ({\copyright} 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)}},
  author       = {{Hölzl, Johannes Sebastian and Sextro, Walter}},
  issn         = {{1617-7061}},
  journal      = {{PAMM}},
  number       = {{1}},
  pages        = {{247--248}},
  publisher    = {{WILEY-VCH Verlag}},
  title        = {{{Reibungsdämpfung in ausgedehnten, verschraubten Fügestellen}}},
  doi          = {{10.1002/pamm.201010116}},
  volume       = {{10}},
  year         = {{2010}},
}

@article{9748,
  abstract     = {{For many technical applications it is necessary to avoid or to reduce vibrations. Factors benefiting from vibration reduction are for example the durability of the application, which is increased, as well as cost expenses and the level of noise, which are both decreased. Rough, bolted interfaces are common in most machines and can be used as damping devices with some effort. Perhaps in future such contact surfaces could be used as damping devices at the interfaces of an automotive engine or exhaust system. Nevertheless it is difficult to predict the effect of a change in contact interface parameters on the dynamic behavior of the entire mechanical system. Therefore a method for calculating the steady state behavior of elastic multi-body systems was developed. The basis of this method is a finite element model of each contacting unit. On each model a modal reduction is applied in order to reduce the degrees of freedom. The method of Ritz and Galerkin is used to calculate the frequency response functions of the reduced system including contact. This method allows the calculation of the steady-state behavior of elastic multi-body systems with rough, bolted contact interfaces, by taking the pre-stress of the bolts, the roughness and the friction coefficient of the contacting surfaces as parameters. In order to verify calculated results, a test stand was built. The comparison of calculated and experimental results showed a satisfying correlation.}},
  author       = {{ Hölzl, Johannes Sebastian and Sextro, Walter}},
  journal      = {{SAE International Journal of Passenger Cars- Mechanical Systems}},
  keywords     = {{Automotive}},
  pages        = {{929--935}},
  title        = {{{Simulation of the Dynamical Behavior of Elastic Multi-Body Systems with Bolted, Rough Contact Interfaces}}},
  doi          = {{10.4271/2010-01-1422}},
  year         = {{2010}},
}

@inproceedings{9753,
  abstract     = {{Piezoelektrische Trägheitsmotoren nutzen die Trägheit einer bewegten Masse, um diese in kleinen Schritten durch abwechselnde Haft- und Gleitphasen voranzutreiben. Eine Kernfrage bei der Entwicklung eines piezoelektrischen Trägheitsmotors ist, welches elektrische Ansteuersignal für das gewünschte Motorverhalten optimal ist. Das elektrische Signal führt zu einer Bewegung des piezoelektrischen Aktors und damit der Antriebsstange, die den reibschlüssigen Vortrieb bewirkt. Entsprechend wird diese Fragestellung in zwei Teilen untersucht: Anhand eines Starrkörpermodells werden zunächst Bewegungsverläufe für die Antriebsstange ermittelt, mit denen die maximale Geschwindigkeit erreicht wird. Dabei werden drei Antriebsmodi identifiziert. Mit allen kann eine höhere Geschwindigkeit als mit der heute häufig verwendeten Sägezahnanregung erreicht werden. Anschließend wird ein einfaches dynamisches Modell eines piezoelektrischen Aktors genutzt, um die notwendigen elektrischen Ansteuersignale für die verschiedenen Antriebsmodi zu bestimmen. Es zeigt sich, dass das gewählte einfache Modell hierzu nur bedingt geeignet ist.}},
  author       = {{Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}},
  booktitle    = {{7. Paderborner Workshop Entwurf mechatronischer Systeme}},
  editor       = {{Gausemeier, Jürgen and Rammig, Franz and Schäfer, Wilhelm and Trächtler, Ansgar}},
  issn         = {{0924-4247}},
  keywords     = {{Piezoelektrischer Trägheitsmotoren}},
  pages        = {{129--141}},
  publisher    = {{Heinz Nixdorf Institut, Universität Paderborn}},
  title        = {{{Anregungskonzepte und Modellierung piezoelektrischer Trägheitsmotoren}}},
  volume       = {{272}},
  year         = {{2010}},
}

@inproceedings{9754,
  abstract     = {{A model based design approach for improved piezoelectric inertia motors is presented. Three velocityoptimized movement patterns for the driving body have been derived. The influence of the motor parameters and the process of designing an application specific motor with maximum velocity are shown. A simple dynamic model of the piezoelectric actuator is used to calculate the voltage signal for achieving the desired movement pattern. Observed distortions of the optimum pattern, their influence on the motion of the driven body and different methods to reduce them are discussed.}},
  author       = {{Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}},
  booktitle    = {{ACTUATOR 2010 Conference Proceedings}},
  issn         = {{0924-4247}},
  pages        = {{657--661}},
  title        = {{{Improving the Performance of Piezoelectric Inertia Motors}}},
  year         = {{2010}},
}

@inproceedings{9760,
  abstract     = {{Self-optimizing systems are able to adapt their behavior autonomously according to their current self-determined objectives. Unforeseen influences could lead to dependability-critical behavior of the system. Methods are required which secure self-optimizing systems during operation. These methods to increase the dependability of the system should already be taken into consideration in the design process. This paper presents a guideline for the dependability-oriented design of self-optimizing systems, which integrates established classical methods like failure mode and effects analysis as well as methods based on self-optimization. On the one hand self-optimization is used to increase the dependability of the system by integrating objectives like safety, availability, and reliability to the objectives of the system. On the other hand methods are required to ensure the self-optimization itself. As basis for this guideline serves the principle solution of the system. The six phases of the guideline extend the design process and lead to an enhanced principle solution. Additionally, the guideline illustrates phases to implement and validate the self-optimizing system. The proposed guideline is applied to an innovative rail-bound vehicle, called RailCab, which is equipped with self-optimizing function modules.}},
  author       = {{Sondermann-Wölke, Christoph and Hemsel, Tobias and Sextro, Walter and Gausemeier, Jürgen and Pook, Sebastian}},
  booktitle    = {{Industrial Informatics (INDIN), 2010 8th IEEE International Conference on}},
  keywords     = {{RailCab, dependability-critical behavior, dependability-oriented design, failure mode, rail-bound vehicle, secure self-optimizing systems, self-optimizing function modules, optimisation, railways, self-adjusting systems}},
  pages        = {{739 --744}},
  title        = {{{Guideline for the dependability-oriented design of self-optimizing systems}}},
  doi          = {{10.1109/INDIN.2010.5549490}},
  year         = {{2010}},
}

