@inproceedings{56834,
  author       = {{Friesen, Olga and Claes, Leander and Scheidemann, Claus and Feldmann, Nadine and Hemsel, Tobias and Henning, Bernd}},
  booktitle    = {{2023 International Congress on Ultrasonics, Beijing, China}},
  issn         = {{1742-6596}},
  pages        = {{012125}},
  publisher    = {{IOP Publishing}},
  title        = {{{Estimation of temperature-dependent piezoelectric material parameters using ring-shaped specimens}}},
  doi          = {{10.1088/1742-6596/2822/1/012125}},
  volume       = {{2822}},
  year         = {{2024}},
}

@article{56777,
  abstract     = {{The estimation of accurate piezoelectric material parameters is a fundamental prerequisite for simulation-driven design of piezoelectric actuators and sensors. Previous studies show that a full set of material parameters can be determined in an inverse procedure using a single disc-shaped specimen with an electrode structured for increased sensitivity with respect to all material parameters. However, in the case of high-power actuator applications, ring-shaped piezoelectric components are often employed, necessitating an adaptation of the previously developed method. The alteration in geometry introduces some advantages. Accordingly, there is no longer any requirement to modify the electrode structure in order to enhance sensitivity. The method to estimate the material parameters presented here consists of a total of three stages. An initial, approximate estimation of the material parameters is determined using analytical approximations for the resonance frequencies from the IEEE standard. These values are optimised in an inverse procedure that employs analytic expressions for the electrical impedance of piezoelectric rings as the forward model. Further refinement is achieved by using Finite Element (FE) simulations as the forward model again in an inverse procedure. The method is applied to electrical impedance measurement data, yielding material parameters for hard piezoelectric rings. The result shows a good agreement between the simulation and measurement results, indicating realistic material parameter values.}},
  author       = {{Friesen, Olga and Claes, Leander and Feldmann, Nadine and Henning, Bernd}},
  issn         = {{2196-7113}},
  journal      = {{tm - Technisches Messen}},
  publisher    = {{De Gruyter}},
  title        = {{{Estimation of piezoelectric material parameters of ring-shaped specimens}}},
  doi          = {{https://doi.org/10.1515/teme-2024-0107}},
  year         = {{2024}},
}

@article{45445,
  author       = {{Claes, Leander and Feldmann, Nadine and Schulze, Veronika and Meihost, Lars and Kuhlmann, Henrik and Jurgelucks, Benjamin and Walther, Andrea and Henning, Bernd}},
  journal      = {{Journal of Sensors and Sensor Systems}},
  number       = {{1}},
  pages        = {{163–173}},
  title        = {{{Inverse procedure for measuring piezoelectric material parameters using a single multi-electrode sample}}},
  doi          = {{10.5194/jsss-12-163-2023}},
  volume       = {{12}},
  year         = {{2023}},
}

@article{6579,
  abstract     = {{An explicit approach using symplectic time integration in conjunction with traditional finite difference spatial derivatives to solve the wave equation in moving media is presented. A simple operator split of this second order wave equation into two coupled first order equations is performed, allowing these split equations to be solved symplectically. Orders of symplectic time integration ranging from first to fourth along with orders of spatial derivatives ranging from second to sixth are explored. The case of cylindrical acoustic spreading in air under a constant velocity in a 2D square structured domain is considered. The variation of the computed time-of-flight, frequency, and wave length are studied with varying grid resolution and the deviations from the analytical solutions are determined. It was found that symplectic time integration interferes with finite difference spatial derivatives higher than second order causing unexpected results. This is actually beneficial for unstructured finite volume tools like OpenFOAM where second order spatial operators are the state-of-the art. Cylindrical acoustic spreading is simulated on an unstructured 2D triangle mesh showing that symplectic time integration is not limited to the spatial discretization paradigm and overcomes the numerical diffusion arising with the in-built numerical methods which hinder wave propagation.}},
  author       = {{Inguva, Venkatesh and Feldmann, Nadine and Claes, Leander and Koturbash, Taras and Hahn-Jose, Thomas and Koutcherov, Vladimir and Kenig, Eugeny}},
  journal      = {{Engineering Reports}},
  title        = {{{An explicit symplectic approach to solving the wave equation in moving media}}},
  doi          = {{10.1002/eng2.12573}},
  year         = {{2022}},
}

@article{30863,
  abstract     = {{<jats:title>Abstract</jats:title>
               <jats:p>In this paper a measurement procedure to identify viscoelastic material parameters of plate-like samples using broadband ultrasonic waves is presented. Ultrasonic Lamb waves are excited via the thermoelastic effect using laser radiation and detected by a piezoelectric transducer. The resulting measurement data is transformed to yield information about multiple propagating Lamb waves as well as their attenuation. These results are compared to simulation results in an inverse procedure to identify the parameters of an elastic and a viscoelastic material model.</jats:p>}},
  author       = {{Johannesmann, Sarah and Claes, Leander and Feldmann, Nadine and Zeipert, Henning and Henning, Bernd}},
  issn         = {{2196-7113}},
  journal      = {{tm - Technisches Messen}},
  keywords     = {{Electrical and Electronic Engineering, Instrumentation}},
  number       = {{7 - 8}},
  pages        = {{493 -- 506}},
  publisher    = {{Walter de Gruyter GmbH}},
  title        = {{{Lamb wave based approach to the determination of acoustic material parameters}}},
  doi          = {{10.1515/teme-2021-0134}},
  volume       = {{89}},
  year         = {{2022}},
}

@inproceedings{6553,
  author       = {{Claes, Leander and Feldmann, Nadine and Schulze, Veronika and Jurgelucks, Benjamin and Walther, Andrea and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2022}},
  location     = {{Stuttgart}},
  pages        = {{1326--1329}},
  title        = {{{Identification of piezoelectric material parameters using optimised multi-electrode specimens}}},
  year         = {{2022}},
}

@misc{6558,
  author       = {{Friesen, Olga and Claes, Leander and Feldmann, Nadine and Henning, Bernd}},
  title        = {{{Estimation of piezoelectric material parameters of ring-shaped specimens}}},
  year         = {{2022}},
}

@article{21082,
  author       = {{Itner, Dominik and Gravenkamp, Hauke and Dreiling, Dmitrij and Feldmann, Nadine and Henning, Bernd}},
  issn         = {{1617-7061}},
  journal      = {{PAMM}},
  title        = {{{Simulation of guided waves in cylinders subject to arbitrary boundary conditions for applications in material characterization}}},
  doi          = {{10.1002/pamm.202000232}},
  year         = {{2021}},
}

@misc{21564,
  author       = {{Itner, Dominik and Gravenkamp, Hauke and Dreiling, Dmitrij and Feldmann, Nadine and Henning, Bernd}},
  title        = {{{On the forward simulation and cost functions for the ultrasonic material characterization of polymers }}},
  year         = {{2021}},
}

@inproceedings{25265,
  abstract     = {{Waveguide-based methods can be used for the non-destructive determination of acoustic material parameters. One of these methods is based on transmission measurements of cylindrical polymeric specimens. Here, the experimental setup consists of two transducers, which excite and receive the waveguide modes at the faces of the cylinder. The measurement, as well as a forward model, are used to determine material parameters of the polymeric specimen in an inverse approach.
1-3 piezoelectric composites are used as an active element because they can be approximated by a thickness vibration only. This allows an easy identification of Mason model parameters to characterise the transducers’ vibration behaviour. 
However, sensitivity analysis shows a high uncertainty in the determination of the mechanical shear parameters due to the uniform excitation. To increase the sensitivity to these shear motions, arbitrary excitations were investigated by means of numerical simulation. 
In order to be able to realise the determined optimal excitation, new transducer prototypes were designed. By subdividing the electrodes of the active element, for example, ring-shaped excitation is feasible. Furthermore, it can be shown that modelling these transducers with a one-dimensional Mason model is sufficient.}},
  author       = {{Dreiling, Dmitrij and Itner, Dominik and Feldmann, Nadine and Scheidemann, Claus and Gravenkamp, Hauke and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2021}},
  location     = {{Wien}},
  publisher    = {{Deutsche Gesellschaft für Akustik e.V. (DEGA)}},
  title        = {{{Application and modelling of ultrasonic transducers using 1-3 piezoelectric composites with structured electrodes}}},
  year         = {{2021}},
}

@inproceedings{40541,
  author       = {{Itner, D. and Gravenkamp, H. and Dreiling, Dmitrij and Feldmann, Nadine and Henning, Bernd}},
  booktitle    = {{14th WCCM-ECCOMAS Congress}},
  publisher    = {{CIMNE}},
  title        = {{{Simulation of Guided Waves in Cylinders Subject to Arbitrary Boundary Conditions Using the Scaled Boundary Finite Element Method}}},
  doi          = {{10.23967/wccm-eccomas.2020.307}},
  volume       = {{700}},
  year         = {{2021}},
}

@article{21232,
  author       = {{Itner, Dominik and Gravenkamp, Hauke and Dreiling, Dmitrij and Feldmann, Nadine and Henning, Bernd}},
  issn         = {{0041-624X}},
  journal      = {{Ultrasonics}},
  title        = {{{Efficient semi-analytical simulation of elastic guided waves in cylinders subject to arbitrary non-symmetric loads}}},
  doi          = {{10.1016/j.ultras.2021.106389}},
  year         = {{2021}},
}

@phdthesis{6563,
  abstract     = {{Designprozesse von Schallwandlern werden durch zunehmende Rechenkapazitäten immer mehr durch simulative Betrachtungen unterstützt. Dabei ist vor allem die Wahl der Materialparameter der verwendeten Materialien wichtig für ein realitätsnahes Simulationsergebnis. Bei Schallwandlern werden häufig Piezokeramiken als aktive Elemente genutzt, welche sich durch eine Verkopplung mechanischer und elektrischer Eigenschaften auszeichnen. Zur Bestimmung ihrer Materialparameter stellt der IEEE Standard on Piezoelectricity ein standardisiertes Verfahren dar. Dazu sind fünf Impedanzmessungen an vier unterschiedlich gefertigten Probekörpergeometrien notwendig. Da an jedem einzelnen Probekörper nur eine Untermenge aller notwendigen Materialparameter bestimmt werden kann, werden diese dann zu einem kompletten Materialparametersatz zusammengefügt. Aufgrund der unterschiedlichen Prozessbedingungen, bei denen die jeweiligen Probekörper hergestellt werden, ist dieser Materialparametersatz jedoch inkonsistent und kann nie das Verhalten einer einzelnen Probe beschreiben. Daher wird in der vorliegenden Arbeit ein Messverfahren entwickelt, mit dem es möglich ist, alle relevanten Materialparameter unter besonderer Berücksichtigung von Dämpfung an einem einzelnen Probekörper allein durch Impedanzmessungen zu bestimmen. Als Probekörper wird dazu eine in der Anwendung häufig verwendete Scheibengeometrie verwendet. Um eine hinreichend hohe Sensitivität auf alle Materialparameter zu gewährleisten, wird diese mit einer optimierten Elektrodentopologie gefertigt. Da in diesem Fall keine analytische Betrachtung mehr möglich ist, wird das Messverfahren durch einen inversen Ansatz realisiert.}},
  author       = {{Feldmann, Nadine}},
  pages        = {{184}},
  publisher    = {{Universität Paderborn}},
  title        = {{{	 Ein modellbasiertes Messverfahren zur Charakterisierung von Piezokeramiken unter Verwendung eines einzelnen scheibenförmigen Probekörpers}}},
  doi          = {{10.17619/UNIPB/1-1264}},
  year         = {{2021}},
}

@article{21341,
  abstract     = {{The progress in numerical methods and simulation tools promotes the use of inverse problems in material characterisation problems. A newly developed procedure can be used to identify the behaviour of piezoceramic discs over a wide frequency range using a single specimen via fitting simulated and measured impedances by optimising the underlying material parameters. Since there is no generally accepted damping model for piezoelectric ceramics, several mechanical damping models are examined for the material identification. Three models have been chosen and their ability to replicate the measured impedances is evaluated. On the one hand, the common Rayleigh model is considered as a reference. On the other hand, a Zener model and a model using complex constants are extended to model the transversely isotropic material. As the Rayleigh model is only valid for a limited frequency range, it fails to model the broadband behaviour of the material. The model using complex constants leads to the best fit over a wide frequency range while at the same time only adding three additional parameters for modelling damping. Thus, damping can be assumed approximately frequency-independent in piezoceramics.}},
  author       = {{Feldmann, Nadine and Schulze, Veronika and Claes, Leander and Jurgelucks, Benjamin and Meihost, Lars and Walther, Andrea and Henning, Bernd}},
  issn         = {{2196-7113}},
  journal      = {{tm - Technisches Messen}},
  number       = {{5}},
  pages        = {{294 -- 302}},
  title        = {{{Modelling damping in piezoceramics: A comparative study}}},
  doi          = {{10.1515/teme-2020-0096}},
  volume       = {{88}},
  year         = {{2021}},
}

@inproceedings{22012,
  author       = {{Claes, Leander and Feldmann, Nadine and Jurgelucks, Benjamin and Schulze, Veronika and Schmidt, Stephan and Walther, Andrea and Henning, Bernd}},
  location     = {{Nürnberg}},
  pages        = {{237--238}},
  title        = {{{Optimised Multi-Electrode Topology for Piezoelectric Material Characterisation}}},
  doi          = {{10.5162/SMSI2021/A10.1}},
  year         = {{2021}},
}

@misc{21233,
  author       = {{Schulze, Veronika and Schmidt, Stephan and Jurgelucks, Benjamin and Feldmann, Nadine and Claes, Leander}},
  title        = {{{Optimal experiment design with respect to electrode configurations for a piezoelectric problem}}},
  year         = {{2021}},
}

@misc{23462,
  author       = {{Schulze, Veronika and Schmidt, Stephan and Jurgelucks, Benjamin and Feldmann, Nadine and Claes, Leander}},
  title        = {{{Piezoelectric BC Modeling for Electrode Shapes with OED}}},
  year         = {{2021}},
}

@inproceedings{17089,
  author       = {{Dreiling, Dmitrij and Itner, Dominik Thor and Feldmann, Nadine and Gravenkamp, Hauke and Henning, Bernd}},
  location     = {{Nürnberg}},
  publisher    = {{AMA Service GmbH}},
  title        = {{{Increasing the sensitivity in the determination of material parameters by using arbitrary loads in ultrasonic transmission measurements}}},
  doi          = {{10.5162/SMSI2020/D1.3}},
  year         = {{2020}},
}

@inproceedings{15163,
  author       = {{Feldmann, Nadine and Schulze, Veronika and Jurgelucks, Benjamin and Henning, Bernd}},
  booktitle    = {{Fortschritte der Akustik - DAGA 2020}},
  pages        = {{1125--1128}},
  title        = {{{Solving piezoelectric inverse problems using Algorithmic Differentiation}}},
  year         = {{2020}},
}

@article{19313,
  abstract     = {{The increasingly simulation-driven design process of ultrasonic transducers requires several reliable parameters for the description of the material behaviour. Exact results can only be achieved when a single specimen is used in the identification process, which typically is prone to the problem of low sensitivities to certain material parameters and thus high uncertainties. Therefore, a custom electrode topology for increased sensitivity is proposed for a piezoceramic disc. The thereupon conducted measurements of the electric impedance can be used as a starting point for an inverse approach where an equivalent simulation model is used to identify fitting material parameters. An optimisation strategy based on a preliminary sensitivity analysis is presented that leads to a good agreement between measurement and simulation. Furthermore, the proposed measurement procedure is able to evaluate the quality of the simulation model. Hence, different frequency-dependent damping models are presented and evaluated.}},
  author       = {{Feldmann, Nadine and Schulze, Veronika and Claes, Leander and Jurgelucks, Benjamin and Walther, Andrea and Henning, Bernd}},
  issn         = {{2196-7113}},
  journal      = {{tm - Technisches Messen}},
  pages        = {{50--55}},
  title        = {{{Inverse piezoelectric material parameter characterization using a single disc-shaped specimen}}},
  doi          = {{10.1515/teme-2020-0012}},
  year         = {{2020}},
}