[{"year":"2025","quality_controlled":"1","title":"Increasing the sensitivity of ultrasonic transmission measurements for elastic material parameter estimation","publisher":"IOP Publishing","date_created":"2025-05-19T13:30:39Z","abstract":[{"lang":"eng","text":"<jats:title>Abstract</jats:title>\r\n               <jats:p>Ultrasonic transmission measurements can be used for material characterization, as the propagation time of sound waves and thus their velocity depends on the elastic material parameters. Measurement results for the elastic material parameters are acquired non-destructively using ultrasonic transmission measurements of hollow cylindrical polymer specimens. To determine the material parameters, an inverse approach is used comparing measurements with simulated data. Previous studies show that the procedure exhibits low sensitivity with respect to the shear parameters of the material. In order to increase the sensitivity, we propose to apply a spatially annular excitation on the base of the specimen. As a measure to analyse the sensitivities with respect to all parameters and their linear independence, we observe the volume of the parallelotope of the sensitivity vectors. Here, a scaled boundary finite element formulation of wave propagation in the specimen is expanded to yield derivative information directly, and a sensitivity analysis can be carried out efficiently. Finally, the results of this sensitivity analysis with regard to the annular excitation are also applied to the measurement setup.</jats:p>"}],"publication":"Measurement Science and Technology","keyword":["Sensitivity analysis","Ultrasonic transducer","Guided waves","Polymers","Gram determinant"],"language":[{"iso":"eng"}],"citation":{"apa":"Dreiling, D., Itner, D., Gravenkamp, H., Claes, L., Birk, C., &#38; Henning, B. (2025). Increasing the sensitivity of ultrasonic transmission measurements for elastic material parameter estimation. <i>Measurement Science and Technology</i>, <i>36</i>, Article 6. <a href=\"https://doi.org/10.1088/1361-6501/add9b6\">https://doi.org/10.1088/1361-6501/add9b6</a>","bibtex":"@article{Dreiling_Itner_Gravenkamp_Claes_Birk_Henning_2025, title={Increasing the sensitivity of ultrasonic transmission measurements for elastic material parameter estimation}, volume={36}, DOI={<a href=\"https://doi.org/10.1088/1361-6501/add9b6\">10.1088/1361-6501/add9b6</a>}, number={6}, journal={Measurement Science and Technology}, publisher={IOP Publishing}, author={Dreiling, Dmitrij and Itner, Dominik and Gravenkamp, Hauke and Claes, Leander and Birk, Carolin and Henning, Bernd}, year={2025} }","short":"D. Dreiling, D. Itner, H. Gravenkamp, L. Claes, C. Birk, B. Henning, Measurement Science and Technology 36 (2025).","mla":"Dreiling, Dmitrij, et al. “Increasing the Sensitivity of Ultrasonic Transmission Measurements for Elastic Material Parameter Estimation.” <i>Measurement Science and Technology</i>, vol. 36, 6, IOP Publishing, 2025, doi:<a href=\"https://doi.org/10.1088/1361-6501/add9b6\">10.1088/1361-6501/add9b6</a>.","ama":"Dreiling D, Itner D, Gravenkamp H, Claes L, Birk C, Henning B. Increasing the sensitivity of ultrasonic transmission measurements for elastic material parameter estimation. <i>Measurement Science and Technology</i>. 2025;36. doi:<a href=\"https://doi.org/10.1088/1361-6501/add9b6\">10.1088/1361-6501/add9b6</a>","chicago":"Dreiling, Dmitrij, Dominik Itner, Hauke Gravenkamp, Leander Claes, Carolin Birk, and Bernd Henning. “Increasing the Sensitivity of Ultrasonic Transmission Measurements for Elastic Material Parameter Estimation.” <i>Measurement Science and Technology</i> 36 (2025). <a href=\"https://doi.org/10.1088/1361-6501/add9b6\">https://doi.org/10.1088/1361-6501/add9b6</a>.","ieee":"D. Dreiling, D. Itner, H. Gravenkamp, L. Claes, C. Birk, and B. Henning, “Increasing the sensitivity of ultrasonic transmission measurements for elastic material parameter estimation,” <i>Measurement Science and Technology</i>, vol. 36, Art. no. 6, 2025, doi: <a href=\"https://doi.org/10.1088/1361-6501/add9b6\">10.1088/1361-6501/add9b6</a>."},"intvolume":"        36","publication_status":"published","publication_identifier":{"issn":["0957-0233","1361-6501"]},"main_file_link":[{"open_access":"1","url":"https://iopscience.iop.org/article/10.1088/1361-6501/add9b6"}],"doi":"10.1088/1361-6501/add9b6","oa":"1","date_updated":"2025-05-27T15:03:38Z","author":[{"full_name":"Dreiling, Dmitrij","id":"32616","last_name":"Dreiling","first_name":"Dmitrij"},{"last_name":"Itner","full_name":"Itner, Dominik","first_name":"Dominik"},{"last_name":"Gravenkamp","full_name":"Gravenkamp, Hauke","first_name":"Hauke"},{"first_name":"Leander","id":"11829","full_name":"Claes, Leander","orcid":"0000-0002-4393-268X","last_name":"Claes"},{"last_name":"Birk","full_name":"Birk, Carolin","first_name":"Carolin"},{"first_name":"Bernd","full_name":"Henning, Bernd","id":"213","last_name":"Henning"}],"volume":36,"status":"public","type":"journal_article","article_type":"original","article_number":"6","funded_apc":"1","project":[{"_id":"89","name":"VaMP: Vollständige Bestimmung der akustischen Materialparameter von Polymeren","grant_number":"409779252"}],"_id":"59995","user_id":"32616","department":[{"_id":"49"}]},{"type":"journal_article","status":"public","department":[{"_id":"630"}],"user_id":"93720","_id":"61825","project":[{"_id":"130","name":"TRR 285:  Methodenentwicklung zur mechanischen Fügbarkeit in wandlungsfähigen Prozessketten"},{"_id":"133","name":"TRR 285 - Project Area C"},{"_id":"149","name":"TRR 285 - Subproject C05"}],"article_number":"025401","publication_identifier":{"issn":["0957-0233","1361-6501"]},"publication_status":"published","intvolume":"        36","citation":{"ieee":"L. Butzhammer, N. Handke, S. Wittl, G. Herl, and T. Hausotte, “Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom,” <i>Measurement Science and Technology</i>, vol. 36, no. 2, Art. no. 025401, 2025, doi: <a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>.","chicago":"Butzhammer, Lorenz, Niklas Handke, Simon Wittl, Gabriel Herl, and Tino Hausotte. “Direct Assessment of the Influence of Pose Repeatability on the Accuracy of Dimensional Measurements for Computed Tomography Systems with High Degrees of Freedom.” <i>Measurement Science and Technology</i> 36, no. 2 (2025). <a href=\"https://doi.org/10.1088/1361-6501/ada05a\">https://doi.org/10.1088/1361-6501/ada05a</a>.","ama":"Butzhammer L, Handke N, Wittl S, Herl G, Hausotte T. Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom. <i>Measurement Science and Technology</i>. 2025;36(2). doi:<a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>","mla":"Butzhammer, Lorenz, et al. “Direct Assessment of the Influence of Pose Repeatability on the Accuracy of Dimensional Measurements for Computed Tomography Systems with High Degrees of Freedom.” <i>Measurement Science and Technology</i>, vol. 36, no. 2, 025401, IOP Publishing, 2025, doi:<a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>.","bibtex":"@article{Butzhammer_Handke_Wittl_Herl_Hausotte_2025, title={Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom}, volume={36}, DOI={<a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>}, number={2025401}, journal={Measurement Science and Technology}, publisher={IOP Publishing}, author={Butzhammer, Lorenz and Handke, Niklas and Wittl, Simon and Herl, Gabriel and Hausotte, Tino}, year={2025} }","short":"L. Butzhammer, N. Handke, S. Wittl, G. Herl, T. Hausotte, Measurement Science and Technology 36 (2025).","apa":"Butzhammer, L., Handke, N., Wittl, S., Herl, G., &#38; Hausotte, T. (2025). Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom. <i>Measurement Science and Technology</i>, <i>36</i>(2), Article 025401. <a href=\"https://doi.org/10.1088/1361-6501/ada05a\">https://doi.org/10.1088/1361-6501/ada05a</a>"},"volume":36,"author":[{"first_name":"Lorenz","last_name":"Butzhammer","full_name":"Butzhammer, Lorenz"},{"full_name":"Handke, Niklas","last_name":"Handke","first_name":"Niklas"},{"first_name":"Simon","last_name":"Wittl","full_name":"Wittl, Simon"},{"first_name":"Gabriel","full_name":"Herl, Gabriel","last_name":"Herl"},{"full_name":"Hausotte, Tino","last_name":"Hausotte","first_name":"Tino"}],"date_updated":"2026-02-12T10:45:36Z","oa":"1","doi":"10.1088/1361-6501/ada05a","main_file_link":[{"open_access":"1","url":"https://iopscience.iop.org/article/10.1088/1361-6501/ada05a/pdf"}],"publication":"Measurement Science and Technology","abstract":[{"text":"<jats:title>Abstract</jats:title>\r\n               <jats:p>Industrial x-ray computed tomography (CT) systems with high geometric flexibility are increasingly utilized for large-scale measurement objects or challenging measurement tasks. To maintain high accuracy when deviating from the established circular scan trajectory, trajectory calibration methods using multi-sphere reference objects with known marker positions are commonly employed. These multi-sphere objects can either be scanned together with the measurement object (online trajectory calibration) or in a separate scan (offline trajectory calibration). While offline calibration increases machine time, it generally results in higher scan quality. However, a sufficient pose repeatability is necessary to ensure comparable or even superior accuracy to online calibration. In this contribution, we present a straightforward procedure to compare both types of trajectory calibration in a way that the differences of the results can directly be traced back to the influence of the pose repeatability. The multi-sphere reference object is not only used for trajectory calibration, but simultaneously as a measurement object for repeated measurements. The methodology is tested on both a twin robotic CT system and a conventional CT system that is additionally equipped with a hexapod manipulator for adaptive object tilting. Results showed, independent from the type of trajectory calibration, systematic measurement errors in the order of 10<jats:sup>−5</jats:sup>–10<jats:sup>−4</jats:sup> of measured sphere distances and sphericity values below 50 <jats:inline-formula>\r\n                     <jats:tex-math/>\r\n                     <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\">\r\n                        <mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mtext>μ</mml:mtext>\r\n                           </mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mi mathvariant=\"normal\">m</mml:mi>\r\n                           </mml:mrow>\r\n                        </mml:mrow>\r\n                     </mml:math>\r\n                  </jats:inline-formula>. For sphere distances, random errors were increased by a factor of 5 due to the offline trajectory calibration, but were still low (<jats:inline-formula>\r\n                     <jats:tex-math/>\r\n                     <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\">\r\n                        <mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mo>&lt;</mml:mo>\r\n                           </mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mn>1</mml:mn>\r\n                           </mml:mrow>\r\n                           <mml:mstyle scriptlevel=\"0\"/>\r\n                           <mml:mrow>\r\n                              <mml:mtext>μ</mml:mtext>\r\n                           </mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mi mathvariant=\"normal\">m</mml:mi>\r\n                           </mml:mrow>\r\n                        </mml:mrow>\r\n                     </mml:math>\r\n                  </jats:inline-formula>) in comparison to systematic errors and the spread of different measurement features. Overall, both investigated systems demonstrated sufficient positioning repeatability for offline trajectory calibration. The method is in general also applicable to any other types of manipulator systems used for CT devices. It provides a workflow for the decision which type of trajectory calibration is preferable for a given CT system.</jats:p>","lang":"eng"}],"language":[{"iso":"eng"}],"issue":"2","quality_controlled":"1","year":"2025","date_created":"2025-10-14T13:50:32Z","publisher":"IOP Publishing","title":"Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom"},{"title":"Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom","doi":"10.1088/1361-6501/ada05a","date_updated":"2025-10-11T08:00:02Z","publisher":"IOP Publishing","author":[{"full_name":"Butzhammer, Lorenz","last_name":"Butzhammer","first_name":"Lorenz"},{"first_name":"Niklas","last_name":"Handke","full_name":"Handke, Niklas"},{"full_name":"Wittl, Simon","last_name":"Wittl","first_name":"Simon"},{"first_name":"Gabriel","last_name":"Herl","full_name":"Herl, Gabriel"},{"first_name":"Tino","last_name":"Hausotte","full_name":"Hausotte, Tino"}],"date_created":"2025-10-11T07:56:47Z","volume":36,"year":"2024","citation":{"apa":"Butzhammer, L., Handke, N., Wittl, S., Herl, G., &#38; Hausotte, T. (2024). Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom. <i>Measurement Science and Technology</i>, <i>36</i>(2), Article 025401. <a href=\"https://doi.org/10.1088/1361-6501/ada05a\">https://doi.org/10.1088/1361-6501/ada05a</a>","bibtex":"@article{Butzhammer_Handke_Wittl_Herl_Hausotte_2024, title={Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom}, volume={36}, DOI={<a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>}, number={2025401}, journal={Measurement Science and Technology}, publisher={IOP Publishing}, author={Butzhammer, Lorenz and Handke, Niklas and Wittl, Simon and Herl, Gabriel and Hausotte, Tino}, year={2024} }","mla":"Butzhammer, Lorenz, et al. “Direct Assessment of the Influence of Pose Repeatability on the Accuracy of Dimensional Measurements for Computed Tomography Systems with High Degrees of Freedom.” <i>Measurement Science and Technology</i>, vol. 36, no. 2, 025401, IOP Publishing, 2024, doi:<a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>.","short":"L. Butzhammer, N. Handke, S. Wittl, G. Herl, T. Hausotte, Measurement Science and Technology 36 (2024).","ama":"Butzhammer L, Handke N, Wittl S, Herl G, Hausotte T. Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom. <i>Measurement Science and Technology</i>. 2024;36(2). doi:<a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>","chicago":"Butzhammer, Lorenz, Niklas Handke, Simon Wittl, Gabriel Herl, and Tino Hausotte. “Direct Assessment of the Influence of Pose Repeatability on the Accuracy of Dimensional Measurements for Computed Tomography Systems with High Degrees of Freedom.” <i>Measurement Science and Technology</i> 36, no. 2 (2024). <a href=\"https://doi.org/10.1088/1361-6501/ada05a\">https://doi.org/10.1088/1361-6501/ada05a</a>.","ieee":"L. Butzhammer, N. Handke, S. Wittl, G. Herl, and T. Hausotte, “Direct assessment of the influence of pose repeatability on the accuracy of dimensional measurements for computed tomography systems with high degrees of freedom,” <i>Measurement Science and Technology</i>, vol. 36, no. 2, Art. no. 025401, 2024, doi: <a href=\"https://doi.org/10.1088/1361-6501/ada05a\">10.1088/1361-6501/ada05a</a>."},"intvolume":"        36","publication_status":"published","publication_identifier":{"issn":["0957-0233","1361-6501"]},"issue":"2","article_number":"025401","language":[{"iso":"eng"}],"_id":"61788","user_id":"107107","abstract":[{"lang":"eng","text":"<jats:title>Abstract</jats:title>\r\n               <jats:p>Industrial x-ray computed tomography (CT) systems with high geometric flexibility are increasingly utilized for large-scale measurement objects or challenging measurement tasks. To maintain high accuracy when deviating from the established circular scan trajectory, trajectory calibration methods using multi-sphere reference objects with known marker positions are commonly employed. These multi-sphere objects can either be scanned together with the measurement object (online trajectory calibration) or in a separate scan (offline trajectory calibration). While offline calibration increases machine time, it generally results in higher scan quality. However, a sufficient pose repeatability is necessary to ensure comparable or even superior accuracy to online calibration. In this contribution, we present a straightforward procedure to compare both types of trajectory calibration in a way that the differences of the results can directly be traced back to the influence of the pose repeatability. The multi-sphere reference object is not only used for trajectory calibration, but simultaneously as a measurement object for repeated measurements. The methodology is tested on both a twin robotic CT system and a conventional CT system that is additionally equipped with a hexapod manipulator for adaptive object tilting. Results showed, independent from the type of trajectory calibration, systematic measurement errors in the order of 10<jats:sup>−5</jats:sup>–10<jats:sup>−4</jats:sup> of measured sphere distances and sphericity values below 50 <jats:inline-formula>\r\n                     <jats:tex-math/>\r\n                     <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\">\r\n                        <mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mtext>μ</mml:mtext>\r\n                           </mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mi mathvariant=\"normal\">m</mml:mi>\r\n                           </mml:mrow>\r\n                        </mml:mrow>\r\n                     </mml:math>\r\n                  </jats:inline-formula>. For sphere distances, random errors were increased by a factor of 5 due to the offline trajectory calibration, but were still low (<jats:inline-formula>\r\n                     <jats:tex-math/>\r\n                     <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" overflow=\"scroll\">\r\n                        <mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mo>&lt;</mml:mo>\r\n                           </mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mn>1</mml:mn>\r\n                           </mml:mrow>\r\n                           <mml:mstyle scriptlevel=\"0\"/>\r\n                           <mml:mrow>\r\n                              <mml:mtext>μ</mml:mtext>\r\n                           </mml:mrow>\r\n                           <mml:mrow>\r\n                              <mml:mi mathvariant=\"normal\">m</mml:mi>\r\n                           </mml:mrow>\r\n                        </mml:mrow>\r\n                     </mml:math>\r\n                  </jats:inline-formula>) in comparison to systematic errors and the spread of different measurement features. Overall, both investigated systems demonstrated sufficient positioning repeatability for offline trajectory calibration. The method is in general also applicable to any other types of manipulator systems used for CT devices. It provides a workflow for the decision which type of trajectory calibration is preferable for a given CT system.</jats:p>"}],"status":"public","type":"journal_article","publication":"Measurement Science and Technology"},{"language":[{"iso":"eng"}],"keyword":["Applied Mathematics","Instrumentation","Engineering (miscellaneous)"],"publication":"Measurement Science and Technology","abstract":[{"lang":"eng","text":"In industrial x-ray computed tomography (CT), the application of more complex scan paths in comparison to the typical circular trajectory (${360}^{\\circ}$ rotation of the measurement object) can extend the potential of CT. One way to enable such 3D scan trajectories is to use a 6-degrees-of-freedom (DOF) object manipulator system. In our case, a hexapod is mounted on top of the rotary table of a commercial CT scanner. This allows for adaptive tilting of the measurement object during the scan. For high accuracy, the geometry calibration of such setups is typically done using the x-ray projections of a calibrated multi-sphere object. Contrary to this, here, we demonstrate a procedure that is based on only a single sphere and can therefore experimentally be implemented with low effort. Using the intrinsic geometry parameters of the CT device as prior information, the hexapod coordinate system with respect to the CT machine coordinate system is determined by means of a one-step optimization approach. The resulting parameters are used to calculate projection matrices that enable the volume reconstruction for 3D scan trajectories. The method is validated using simulated x-ray images and experimental investigations including dimensional measurements. For the used setup, geometric measurement results for 3D scan trajectories that are calibrated with the presented method show in sum increased errors compared to the circular scans. A limited pose accuracy of the manipulator system is discussed as a potential cause. The results nevertheless indicate that the presented method is generally feasible for dimensional CT measurements provided that the pose accuracy is sufficient. The calibration procedure can therefore be a low-cost and easier to implement alternative compared to trajectory calibration methods based on multi-sphere objects, but with a tendency towards lower measurement accuracy. The methodology can in principle be transferred to different setups with 6-DOF manipulator systems, e.g. C-arm CT devices with a robot arm."}],"date_created":"2022-12-07T10:46:14Z","publisher":"IOP Publishing","title":"Calibration of 3D scan trajectories for an industrial computed tomography setup with 6-DOF object manipulator system using a single sphere","issue":"1","year":"2022","department":[{"_id":"630"}],"user_id":"7850","_id":"34264","project":[{"grant_number":"418701707","name":"TRR 285: TRR 285","_id":"130"},{"_id":"133","name":"TRR 285 - C: TRR 285 - Project Area C"},{"_id":"149","name":"TRR 285 – C05: TRR 285 - Subproject C05"}],"article_number":"015403","type":"journal_article","status":"public","volume":34,"author":[{"last_name":"Butzhammer","full_name":"Butzhammer, Lorenz","first_name":"Lorenz"},{"first_name":"Andreas Michael","full_name":"Müller, Andreas Michael","last_name":"Müller"},{"first_name":"Tino","full_name":"Hausotte, Tino","last_name":"Hausotte"}],"oa":"1","date_updated":"2023-01-13T14:34:31Z","doi":"10.1088/1361-6501/ac9856","main_file_link":[{"url":"https://iopscience.iop.org/article/10.1088/1361-6501/ac9856","open_access":"1"}],"publication_identifier":{"issn":["0957-0233","1361-6501"]},"publication_status":"published","intvolume":"        34","citation":{"apa":"Butzhammer, L., Müller, A. M., &#38; Hausotte, T. (2022). Calibration of 3D scan trajectories for an industrial computed tomography setup with 6-DOF object manipulator system using a single sphere. <i>Measurement Science and Technology</i>, <i>34</i>(1), Article 015403. <a href=\"https://doi.org/10.1088/1361-6501/ac9856\">https://doi.org/10.1088/1361-6501/ac9856</a>","mla":"Butzhammer, Lorenz, et al. “Calibration of 3D Scan Trajectories for an Industrial Computed Tomography Setup with 6-DOF Object Manipulator System Using a Single Sphere.” <i>Measurement Science and Technology</i>, vol. 34, no. 1, 015403, IOP Publishing, 2022, doi:<a href=\"https://doi.org/10.1088/1361-6501/ac9856\">10.1088/1361-6501/ac9856</a>.","bibtex":"@article{Butzhammer_Müller_Hausotte_2022, title={Calibration of 3D scan trajectories for an industrial computed tomography setup with 6-DOF object manipulator system using a single sphere}, volume={34}, DOI={<a href=\"https://doi.org/10.1088/1361-6501/ac9856\">10.1088/1361-6501/ac9856</a>}, number={1015403}, journal={Measurement Science and Technology}, publisher={IOP Publishing}, author={Butzhammer, Lorenz and Müller, Andreas Michael and Hausotte, Tino}, year={2022} }","short":"L. Butzhammer, A.M. Müller, T. Hausotte, Measurement Science and Technology 34 (2022).","ama":"Butzhammer L, Müller AM, Hausotte T. Calibration of 3D scan trajectories for an industrial computed tomography setup with 6-DOF object manipulator system using a single sphere. <i>Measurement Science and Technology</i>. 2022;34(1). doi:<a href=\"https://doi.org/10.1088/1361-6501/ac9856\">10.1088/1361-6501/ac9856</a>","chicago":"Butzhammer, Lorenz, Andreas Michael Müller, and Tino Hausotte. “Calibration of 3D Scan Trajectories for an Industrial Computed Tomography Setup with 6-DOF Object Manipulator System Using a Single Sphere.” <i>Measurement Science and Technology</i> 34, no. 1 (2022). <a href=\"https://doi.org/10.1088/1361-6501/ac9856\">https://doi.org/10.1088/1361-6501/ac9856</a>.","ieee":"L. Butzhammer, A. M. Müller, and T. Hausotte, “Calibration of 3D scan trajectories for an industrial computed tomography setup with 6-DOF object manipulator system using a single sphere,” <i>Measurement Science and Technology</i>, vol. 34, no. 1, Art. no. 015403, 2022, doi: <a href=\"https://doi.org/10.1088/1361-6501/ac9856\">10.1088/1361-6501/ac9856</a>."}},{"user_id":"94996","_id":"32489","keyword":["Applied Mathematics","Instrumentation","Engineering (miscellaneous)"],"article_number":"094003","publication":"Measurement Science and Technology","type":"journal_article","status":"public","abstract":[{"text":"<jats:title>Abstract</jats:title>\n               <jats:p>The stagnation point heat fluxes of methane/air flames impinging normal on a cylindrical surface were determined experimentally. Light induced phosphorescence from thermographic phosphors was used to investigate surface temperatures at the stagnation point from a nearly 1D laminar premixed flame burning against a water-cooled ceramic tube. The ceramic tube was coated with 1.1% chromium-doped alumina (ruby) at the impingement area and excited with a green light-emitting diode (LED) to measure the surface temperature. The flame temperature profiles were also measured with a thermocouple of type R (Pt/Pt  +  13% Rh). Effects on variations in cold gas velocity (0.1 m s<jats:sup>−1</jats:sup>–0.5 m s<jats:sup>−1</jats:sup>) relative to the flame speed, equivalence ratio (Ф  =  0.85–1.2), burner to impingement surface spacing (<jats:italic>H</jats:italic>/<jats:italic>d</jats:italic>  =  0.5–2) and surface curvature are reported. The stagnation point heat fluxes are strongly influenced by the flame stabilization mechanism, which changes from burner to wall stabilization, which also is seen from the measured flame temperature profiles. Increasing the cold gas velocity of the reactants leads to higher stagnation point heat fluxes. In addition, decreasing the distance between the burner and impingement surface increases the heat flux, with higher heat fluxes recorded for a tube compared to a flat plate.</jats:p>","lang":"eng"}],"volume":30,"date_created":"2022-08-02T10:21:24Z","author":[{"last_name":"Oketch","full_name":"Oketch, Peter Obara","first_name":"Peter Obara"},{"last_name":"Gonchikzhapov","full_name":"Gonchikzhapov, Munko","first_name":"Munko"},{"first_name":"Ulf","full_name":"Bergmann, Ulf","last_name":"Bergmann"},{"first_name":"Burak","last_name":"Atakan","full_name":"Atakan, Burak"}],"publisher":"IOP Publishing","date_updated":"2022-08-15T13:53:14Z","doi":"10.1088/1361-6501/ab217e","title":"Thermographic phosphor heat flux measurements of laminar methane/air flame impinging on a cylindrical surface","issue":"9","publication_identifier":{"issn":["0957-0233","1361-6501"]},"publication_status":"published","intvolume":"        30","citation":{"chicago":"Oketch, Peter Obara, Munko Gonchikzhapov, Ulf Bergmann, and Burak Atakan. “Thermographic Phosphor Heat Flux Measurements of Laminar Methane/Air Flame Impinging on a Cylindrical Surface.” <i>Measurement Science and Technology</i> 30, no. 9 (2019). <a href=\"https://doi.org/10.1088/1361-6501/ab217e\">https://doi.org/10.1088/1361-6501/ab217e</a>.","ieee":"P. O. Oketch, M. Gonchikzhapov, U. Bergmann, and B. Atakan, “Thermographic phosphor heat flux measurements of laminar methane/air flame impinging on a cylindrical surface,” <i>Measurement Science and Technology</i>, vol. 30, no. 9, Art. no. 094003, 2019, doi: <a href=\"https://doi.org/10.1088/1361-6501/ab217e\">10.1088/1361-6501/ab217e</a>.","ama":"Oketch PO, Gonchikzhapov M, Bergmann U, Atakan B. Thermographic phosphor heat flux measurements of laminar methane/air flame impinging on a cylindrical surface. <i>Measurement Science and Technology</i>. 2019;30(9). doi:<a href=\"https://doi.org/10.1088/1361-6501/ab217e\">10.1088/1361-6501/ab217e</a>","apa":"Oketch, P. O., Gonchikzhapov, M., Bergmann, U., &#38; Atakan, B. (2019). Thermographic phosphor heat flux measurements of laminar methane/air flame impinging on a cylindrical surface. <i>Measurement Science and Technology</i>, <i>30</i>(9), Article 094003. <a href=\"https://doi.org/10.1088/1361-6501/ab217e\">https://doi.org/10.1088/1361-6501/ab217e</a>","bibtex":"@article{Oketch_Gonchikzhapov_Bergmann_Atakan_2019, title={Thermographic phosphor heat flux measurements of laminar methane/air flame impinging on a cylindrical surface}, volume={30}, DOI={<a href=\"https://doi.org/10.1088/1361-6501/ab217e\">10.1088/1361-6501/ab217e</a>}, number={9094003}, journal={Measurement Science and Technology}, publisher={IOP Publishing}, author={Oketch, Peter Obara and Gonchikzhapov, Munko and Bergmann, Ulf and Atakan, Burak}, year={2019} }","short":"P.O. Oketch, M. Gonchikzhapov, U. Bergmann, B. Atakan, Measurement Science and Technology 30 (2019).","mla":"Oketch, Peter Obara, et al. “Thermographic Phosphor Heat Flux Measurements of Laminar Methane/Air Flame Impinging on a Cylindrical Surface.” <i>Measurement Science and Technology</i>, vol. 30, no. 9, 094003, IOP Publishing, 2019, doi:<a href=\"https://doi.org/10.1088/1361-6501/ab217e\">10.1088/1361-6501/ab217e</a>."},"year":"2019"},{"date_updated":"2022-01-06T06:51:46Z","volume":26,"date_created":"2019-10-16T14:24:43Z","author":[{"first_name":"Fabian","last_name":"Bause","full_name":"Bause, Fabian"},{"full_name":"Gravenkamp, Hauke","last_name":"Gravenkamp","first_name":"Hauke"},{"first_name":"Jens","last_name":"Rautenberg","full_name":"Rautenberg, Jens"},{"first_name":"Bernd","last_name":"Henning","full_name":"Henning, Bernd"}],"title":"Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization","doi":"10.1088/0957-0233/26/9/095602","publication_identifier":{"issn":["0957-0233"]},"issue":"095602 (17pp)","year":"2015","intvolume":"        26","citation":{"bibtex":"@article{Bause_Gravenkamp_Rautenberg_Henning_2015, title={Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization}, volume={26}, DOI={<a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">10.1088/0957-0233/26/9/095602</a>}, number={095602 (17pp)}, journal={Measurement Science and Technology}, author={Bause, Fabian and Gravenkamp, Hauke and Rautenberg, Jens and Henning, Bernd}, year={2015} }","short":"F. Bause, H. Gravenkamp, J. Rautenberg, B. Henning, Measurement Science and Technology 26 (2015).","mla":"Bause, Fabian, et al. “Transient Modeling of Ultrasonic Guided Waves in Circular Viscoelastic Waveguides for Inverse Material Characterization.” <i>Measurement Science and Technology</i>, vol. 26, no. 095602 (17pp), 2015, doi:<a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">10.1088/0957-0233/26/9/095602</a>.","apa":"Bause, F., Gravenkamp, H., Rautenberg, J., &#38; Henning, B. (2015). Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization. <i>Measurement Science and Technology</i>, <i>26</i>(095602 (17pp)). <a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">https://doi.org/10.1088/0957-0233/26/9/095602</a>","ieee":"F. Bause, H. Gravenkamp, J. Rautenberg, and B. Henning, “Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization,” <i>Measurement Science and Technology</i>, vol. 26, no. 095602 (17pp), 2015.","chicago":"Bause, Fabian, Hauke Gravenkamp, Jens Rautenberg, and Bernd Henning. “Transient Modeling of Ultrasonic Guided Waves in Circular Viscoelastic Waveguides for Inverse Material Characterization.” <i>Measurement Science and Technology</i> 26, no. 095602 (17pp) (2015). <a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">https://doi.org/10.1088/0957-0233/26/9/095602</a>.","ama":"Bause F, Gravenkamp H, Rautenberg J, Henning B. Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization. <i>Measurement Science and Technology</i>. 2015;26(095602 (17pp)). doi:<a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">10.1088/0957-0233/26/9/095602</a>"},"_id":"13893","department":[{"_id":"49"}],"user_id":"15911","keyword":["viscoelasticity","ultrasonics","guided waves","inverse problem","scaled boundary finite element method"],"language":[{"iso":"eng"}],"publication":"Measurement Science and Technology","type":"journal_article","abstract":[{"lang":"eng","text":"In this contribution, we present an efficient approach for the transient and time-causal modeling of guided waves in viscoelastic cylindrical waveguides in the context of ultrasonic material characterization. We use the scaled boundary finite element method (SBFEM) for efficient computation of the phase velocity dispersion. Regarding the viscoelastic behavior of the materials under consideration, we propose a decomposition approach that considers the real-valued frequency dependence of the (visco-)elastic moduli and, separately, of their attenuation. The modal expansion approach is utilized to take the transmitting and receiving transducers into account and to propagate the excited waveguide modes through a waveguide of finite length. The effectiveness of the proposed simulation model is shown by comparison with a standard transient FEM simulation as well as simulation results based on the exact solution of the complex-valued viscoelastic guided wave problem. Two material models are discussed, namely the fractional Zener model and the anti-Zener model; we re-interpret the latter in terms of the Rayleigh damping model. Measurements are taken on a polypropylene sample and the proposed transient simulation model is used for inverse material characterization. The extracted material properties may then be used in computer-aided design of ultrasonic systems."}],"status":"public"},{"date_created":"2019-10-16T14:26:53Z","author":[{"first_name":"Fabian","full_name":"Bause, Fabian","last_name":"Bause"},{"first_name":"Hauke","last_name":"Gravenkamp","full_name":"Gravenkamp, Hauke"},{"last_name":"Rautenberg","full_name":"Rautenberg, Jens","first_name":"Jens"},{"last_name":"Henning","full_name":"Henning, Bernd","id":"213","first_name":"Bernd"}],"date_updated":"2022-01-06T06:51:46Z","doi":"10.1088/0957-0233/26/9/095602","title":"Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization","publication_identifier":{"issn":["0957-0233","1361-6501"]},"publication_status":"published","citation":{"apa":"Bause, F., Gravenkamp, H., Rautenberg, J., &#38; Henning, B. (2015). Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization. <i>Measurement Science and Technology</i>. <a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">https://doi.org/10.1088/0957-0233/26/9/095602</a>","bibtex":"@article{Bause_Gravenkamp_Rautenberg_Henning_2015, title={Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization}, DOI={<a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">10.1088/0957-0233/26/9/095602</a>}, number={095602}, journal={Measurement Science and Technology}, author={Bause, Fabian and Gravenkamp, Hauke and Rautenberg, Jens and Henning, Bernd}, year={2015} }","short":"F. Bause, H. Gravenkamp, J. Rautenberg, B. Henning, Measurement Science and Technology (2015).","mla":"Bause, Fabian, et al. “Transient Modeling of Ultrasonic Guided Waves in Circular Viscoelastic Waveguides for Inverse Material Characterization.” <i>Measurement Science and Technology</i>, 095602, 2015, doi:<a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">10.1088/0957-0233/26/9/095602</a>.","ama":"Bause F, Gravenkamp H, Rautenberg J, Henning B. Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization. <i>Measurement Science and Technology</i>. 2015. doi:<a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">10.1088/0957-0233/26/9/095602</a>","ieee":"F. Bause, H. Gravenkamp, J. Rautenberg, and B. Henning, “Transient modeling of ultrasonic guided waves in circular viscoelastic waveguides for inverse material characterization,” <i>Measurement Science and Technology</i>, 2015.","chicago":"Bause, Fabian, Hauke Gravenkamp, Jens Rautenberg, and Bernd Henning. “Transient Modeling of Ultrasonic Guided Waves in Circular Viscoelastic Waveguides for Inverse Material Characterization.” <i>Measurement Science and Technology</i>, 2015. <a href=\"https://doi.org/10.1088/0957-0233/26/9/095602\">https://doi.org/10.1088/0957-0233/26/9/095602</a>."},"year":"2015","department":[{"_id":"49"}],"user_id":"15911","_id":"13894","language":[{"iso":"eng"}],"article_number":"095602","publication":"Measurement Science and Technology","type":"journal_article","status":"public"}]