@inproceedings{14550, abstract = {{For many applications like level measurement and industry robotics it is of advantage if the directional characteristic of an ultrasonic transducer is changeable or adaptable for the improvement of spatial resolution. Often this goal is reached with the use of ultrasonic transducer arrays, which elements are driven with phase shifted excitation signals. One disadvantage of these solutions is the great effort for building such an array and the multi-channel sensor electronics. In this contribution the directional characteristic of a single air transducer with segmented electrodes is analyzed. Therefore a variable script based finite element model is used to discover the influence of different electrode configurations on the directional characteristic of a single piezoceramic transducer. Especially the influence on the angle of beam and the near field length are evaluated. The used variable model permits an optimization of the configuration with regards to the mentioned criteria. The findings will be used for the development of a level measurement system for bulk solids.}}, author = {{Unverzagt, Carsten and Henning, Bernd}}, keywords = {{Elektrode}}, location = {{Gdansk, Poland}}, title = {{{Finite element simulation of single ultrasonic transducer with segmented electrodes to adjust the directional characteristic}}}, year = {{2011}}, } @inproceedings{14547, abstract = {{There has been a lot of progress in finding measurable quantities of high in- formation content for the inverse determination of piezoelectric material properties. Since some material parameters (mainly \textgreek{e}S 11, e15and cE 44) do not or only marginally influence the electrical impedance over frequency, it is not sufficient to look only at the electri- cal impedance of discoidal piezoceramics [1]. Moreover, the parameter sensitivities vary with respect to the diameter-thickness ratio of the disc and the design of an ultrasonic transducer's piezoceramic has to match other requirements than those of a good material characterization [2, 3]. That is why it is still desirable to find model based approaches for parameter identification that either keep the technical effort low (e.g., only an impedance measurement) or increase speed of the inversion procedure. In this contribution we answer the question if an additional analytical approximation of cE 44, strictly following the ideas of Theocaris [4], in conjunction with a single measured elec- trical impedance will be sufficient for an accurate simulation of both, electrical impedance and surface normal velocity of a piezoceramic disc. Thereby, the remaining parameters are identified by means of the Inverse Method. Furthermore, we use the parameter ap- proximation as an initial guess and limiting boundary to speed up the inverse algorithm if both, electrical impedance and surface normal velocity are taken into account within the optimization procedure.}}, author = {{Rautenberg, Jens and Rupitsch, Stefan J. and Henning, Bernd and Lerch, Reinhard}}, booktitle = {{7th International Workshop on Direct and Inverse Problems in Piezoelectricity}}, title = {{{Utilizing an Analytical Approximation for c44E to Enhance the Inverse Method for Material Parameter Identification of Piezoceramics}}}, year = {{2011}}, } @inproceedings{14561, abstract = {{Semi-analytical approaches for the description of dispersion in acoustic waveguides are based on root finding in a characteristic function. A mode-tracing algorithm helps to find all solutions of this problem by consecutively bracketing single roots. In this contribution we present a multistage and adaptive mode-tracing algorithm, which uses an adaptive step size for the prediction of consecutive solutions as well as an adaptive estimation of the search space around these predictions. Furthermore we present a validation stage to ensure the correlation between consecutive solutions alias waveguide modes.}}, author = {{Bause, Fabian and Rautenberg, Jens and Henning, Bernd}}, location = {{San Diego, California}}, pages = {{719--722}}, title = {{{An improved mode-tracing algorithm to compute dispersion curves of acoustic waveguides}}}, year = {{2010}}, } @inproceedings{14563, abstract = {{Die computergestützte Simulation geführter elastischer Wellen in ein- oder mehrschichtigen Wellenleitern ist in vielen Bereichen der akustischen Forschung ein essentielles Modellierungswerkzeug. Sie ermöglicht, auch in komplexen Systemen, eine Beschreibung der Wellenausbreitungsvorgänge, deren analytische Lösung zu aufwendig oder nicht durchführbar ist. Im ersten Abschnitt dieses Beitrags wird auf den halbanalytischen Solver bzw. die mathematische Formulierung des die Wellenausbreitung beschreibenden Problems eingegangen. Der zweite Abschnitt beinhaltet den mehrstufigen Aufbau eines Tracing-Algorithmus, welcher den Lösungsraum des Solvers adaptiv einschränkt, so dass Leistungsfähigkeit und Robustheit des Gesamtalgorithmus gestärkt werden.}}, author = {{Bause, Fabian and Rautenberg, Jens and Henning, Bernd}}, isbn = {{978-3-9808659-8-2}}, location = {{Berlin}}, pages = {{1027--1028}}, title = {{{Entwicklung und Parametrisierung eines Mode-Tracing Algorithmus für halbanalytische Solver}}}, year = {{2010}}, } @inproceedings{14565, abstract = {{In single transducer applications it would be desirable if the received electrical signal (echo signal) could be evaluated during transmitting. Thereby it is possible to measure very short distances. There are some solutions to realize this, but they have one limitation which prevents the usage in many industrial application. They need a calibration without an echo. The main problem is that this calibration has to be repeated whenever the process parameters like temperature or acoustic load change. This contribution presents an approach which uses a model identification based on different successive measurements which may include echoes. It is done by an impulse response decomposition followed by a principle component analysis. Results of measurements with sine burst excitation and a reflector in front of the transducer are presented.}}, author = {{Schröder, Andreas and Henning, Bernd}}, location = {{San Diego, California}}, pages = {{141--144}}, title = {{{Improved system identification for simultaneous transmitting and receiving in single transducer applications}}}, year = {{2010}}, } @inproceedings{14566, abstract = {{In der Ultraschallmesstechnik (Abstandsmessung, NDT) ist es zur Detektion naheliegender Reflektoren bzw. zur Erfassung der Medienrückwirkung (Wirkung der akustischen Last) notwendig, die Empfangssignale auszuwerten, noch während der Schallwandler mit dem Sendesignal angesteuert wird oder die Sendesignalenergie am Schallwandler noch nicht ausreichend abgeklungen ist. In diesem Beitrag wird eine Schaltung zur Kompensation des Sendesignals beschrieben, welche die unmittelbare Auswertung des Empfangssignals ermöglicht.}}, author = {{Schröder, Andreas and Henning, Bernd}}, isbn = {{978-3-9808659-8-2}}, pages = {{1025--1026}}, title = {{{Interfaceschaltung für einen simultanen Sende- und Empfangsbetrieb mit einem einzelnen Ultraschallwandler}}}, year = {{2010}}, } @misc{14567, author = {{Schröder, Andreas and Rautenberg, Jens and Behlen, H. and Ziegler, Horst and Unverzagt, Carsten and Gaugler, Ulrich and Glatter, T. and Horrn, R. and Kroemer, H. and Schmidt-Schoenian, Axel and Sonnenberg, Hans-Michael and Henning, Bernd}}, title = {{{Messrohr für einen Ultraschall-Durchflussmesser und Ultraschall Durchflussmesser}}}, year = {{2010}}, } @article{13887, author = {{Schröder, Andreas and Rautenberg, Jens and Henning, Bernd}}, issn = {{1875-3892}}, journal = {{Physics Procedia}}, pages = {{1003--1009}}, title = {{{Evaluation of cost functions for FEA based transducer optimization}}}, doi = {{10.1016/j.phpro.2010.01.129}}, year = {{2010}}, } @article{13888, author = {{Unverzagt, Carsten and Olfert, Sergei and Henning, Bernd}}, issn = {{1875-3892}}, journal = {{Physics Procedia}}, pages = {{935--942}}, title = {{{A new method of spatial filtering for Schlieren visualization of ultrasound wave fields}}}, doi = {{10.1016/j.phpro.2010.01.120}}, year = {{2010}}, } @inproceedings{14551, author = {{Henning, Bernd}}, title = {{{PC gestützte Entwicklung von Ultraschallsensoren}}}, year = {{2010}}, } @inproceedings{14552, author = {{Bause, Fabian and Henning, Bernd}}, title = {{{Adaptives Mode-Tracing und numerische Stabilisierung modellierter Anregungsstrukturen für die halbanalytische Simulation geführter Wellen}}}, year = {{2010}}, } @misc{14553, author = {{Bause, Fabian}}, title = {{{Halbanalytische Modellierung akustischer Wellenausbreitung im ein- und mehrschichtigen Wellenleiter}}}, year = {{2010}}, } @misc{14554, author = {{Henning, Bernd}}, title = {{{Effizientes Ultraschalltransducerdesign und Methoden zur akustischen Materialdatenbestimmung}}}, year = {{2010}}, } @misc{15238, author = {{Henning, Bernd}}, title = {{{Methoden und Werkzeuge für einen effizienten Ultraschallsensorentwurf}}}, year = {{2009}}, } @inproceedings{15239, abstract = {{Ultrasonic sensors are widespread in the process industry for example to measure flow, filling level, density or substance concentration in liquid mixtures today. On one side technically high demands are made to the ultrasonic sensors on the other side the production of the ultrasonic sensors has to be more and more cost-efficient. Today, these two contrary demands only can be met by the use of efficient development tools. This contribution describes the state of technology in the field of the computer-assisted ultrasonic transducer development, however, also shows the limits.}}, author = {{Henning, Bernd}}, location = {{Beijing, China}}, title = {{{Trends in ultrasonic transducer design}}}, year = {{2009}}, } @inproceedings{15240, abstract = {{Today, ultrasonic sensor systems are often applied in process technology. For the opening up of new industrial fields of application, such as the non-invasive process tomography, ultrasound sensors are necessary which are stable and adapted optimally under process conditions. Only with such optimized ultrasonic sensors the functionality of the sensor systems can be enlarged decisively with support of a complex measurement data evaluation. This contribution deals especially with the design process.}}, author = {{Henning, Bernd and Rautenberg, Jens and Schröder, Andreas and Unverzagt, Carsten}}, booktitle = {{Proceedings Sensor 2009}}, isbn = {{978-3-9810993-4-8}}, pages = {{47--52}}, title = {{{Ultrasonic Sensors for Process Applications - Sensor Design}}}, year = {{2009}}, } @article{15241, abstract = {{In this contribution, possibilities and methods for computer-assisted design of ultrasound transducers are described. These transducers are essential for an ultrasonic sensor design, e.g. for continuous non-invasive determination of quantities that are important in process technology. To achieve technical reliability and robustness, the precise determination of all acoustic properties of the used sensor materials is of great importance. Problem-oriented modeling, numerical simulation, special optimization algorithms and improved methods for the visualization of propagating waves offer new and promising possibilities for developing ultrasonic transducers with enhanced properties.}}, author = {{Henning, Bernd and Rautenberg, Jens and Unverzagt, Carsten and Schröder, Andreas and Olfert, Sergei}}, journal = {{Journal of Measurement Science and Technology, MST}}, number = {{124012 (11pp)}}, title = {{{Computer assisted design of transducers for ultrasonic sensor systems}}}, volume = {{20}}, year = {{2009}}, } @inproceedings{15242, abstract = {{In non-destructive testing (NDT) with ultrasound the emission of short pulses is essentially if the echoes of nearby obstacles should be separated from the emitted signal. In this contribution a new approach is shown how to gene-rate a short ultrasonic pulse using a 3$-$1 composite transdu-cer. Therefore the ceramic bars, which are embedded in a polymer matrix, will be regarded as an exciter for the entire structure. After the pulse excitation the same bars can also be used for active damping to increase the bandwidth of the entire system. The Mason model serves as a basis for the de-scription of the ultrasonic transducer and is extended to the composite structure. The excitation signal is adaptively mo-dified by a suitable signal processing. Therefore the changes of boundary conditions, like the ambient temperature or acoustic impedance of adjacent media are considered.}}, author = {{Rautenberg, Jens and Olfert, Sergei and Henning, Bernd}}, location = {{Rotterdam, Netherlands}}, pages = {{148--151}}, title = {{{Generating of short ultrasonic pulses using active damping}}}, year = {{2009}}, } @inproceedings{39640, author = {{Wetzlar, Dietmar and Krumme, Matthias}}, booktitle = {{4. CMM-Workshop Innovative Feuchtemessung in Forschung und Praxis}}, location = {{Bad Herrenalb}}, pages = {{101--111}}, title = {{{Berührungslose Materialfeuchtemessung nach dem NIR-Prinzip bei schnell variierendem Messgutabstand}}}, year = {{2009}}, } @misc{15323, author = {{Henning, Bernd}}, title = {{{Tomografische Ultraschallmessverfahren für die Prozessmesstechnik}}}, year = {{2008}}, }