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Cherkasova, Valeriya; Fröhlich, Thomas
Capacitive calibration capabilities in an EMFC balance. - In: 24th IMEKO TC3 International Conference on Measurement of Force, Mass and Torque 2022, (2023), S. 236-241

The article describes the possibilities of calibrating the force constant in an electromagnetic force compensation (EMFC) load cell using the electrostatic force compensation principle. The static and dynamic principles of calibration of the Kibble balance for the electrostatic force constant, as well as calibration by means of compensation of the electrostatic force by the electromagnetic force, are considered. The combination of the two compensation principles in the load cell allows the measurement of forces in the range of 20 pN to 2.2 mN and ensures traceability to national standards. The relative uncertainty in the measurement of forces of about 100 nN is estimated to be about 0.001.



Pabst, Markus; Fröhlich, Thomas
Centre of gravity measuring device. - In: 24th IMEKO TC3 International Conference on Measurement of Force, Mass and Torque 2022, (2023), S. 138-143

This paper describes a new method to measure the height of the centre of gravity of high-sensitive mass artefacts. A measuring device is presented and tested with mass samples of various shapes and densities. The results of the measurements are compared to the geometrical estimated heights of the centre of gravity and further developments of the new instrument are presented.



Darnieder, Maximilian; Wittke, Martin; Pabst, Markus; Fröhlich, Thomas; Theska, René
Monolithic compliant mechanism for an EMFC mass comparator weighing cell. - In: Engineering for a changing world, (2023), 1.4.112, S. 1-14

Mass comparator weighing cells based on electromagnetic force compensation (EMFC) find application in the most demanding force and mass measurement applications. The centerpiece of these devices is a highly sensitive compliant mechanism with thin flexure hinges. The compliant mechanism forms the mechanical part of the mechatronic overall system. A novel mechanism based on an advanced adjustment concept has been developed, manufactured, and experimentally investigated. The adjustment is designed to further reduce the measurement uncertainty for mass comparisons by canceling out first-order error components. The focus is on the mechanical properties: stiffness, tilt sensitivity, and off-center load sensitivity. The elastic stiffness of the compliant mechanism is compensated by introducing a negative gravitational stiffness to enable the compensation of manufacturing deviations and to increase mass resolution.



https://doi.org/10.22032/dbt.58738
Marin, Sebastian; Augustin, Silke; Hein, Georg; Fröhlich, Thomas
Uncertainty of temperature measurement on road samples :
Unsicherheit der Temperaturmessung an Fahrbahnproben. - In: Messunsicherheit praxisgerecht bestimmen – Prüfprozesse in der industriellen Praxis 2023, (2023), S. 221-236

https://doi.org/10.51202/9783181024287-221
Beerel, Joseph; Bartz, Frederik; Fröhlich, Thomas
Messunsicherheit einer Kalibriereinrichtung für Wärmestromsensoren - Unsicherheit der Temperaturdifferenz. - In: Messunsicherheit praxisgerecht bestimmen – Prüfprozesse in der industriellen Praxis 2023, (2023), S. 147-160

https://doi.org/10.51202/9783181024287-147
Bartz, Frederik; Beerel, Joseph; Fröhlich, Thomas; Gehrmann, Stephan
Kalibrierung eines Wärmestromsensors - Prozess, Einflüsse und die Unsicherheit. - In: Messunsicherheit praxisgerecht bestimmen – Prüfprozesse in der industriellen Praxis 2023, (2023), S. 131-146

https://doi.org/10.51202/9783181024287-131
Augustin, Silke; Fröhlich, Thomas; Marin, Sebastian; Balzer, Felix; Hölzel, Sara
Unsicherheit bei der Bestimmung der Oberflächentemperatur bei Messungen mit Koordinatenmessgeräten. - In: Messunsicherheit praxisgerecht bestimmen – Prüfprozesse in der industriellen Praxis 2023, (2023), S. 95-108

https://doi.org/10.51202/9783181024287-95
Pabst, Markus; Fröhlich, Thomas; Hilbrunner, Falko
Planck-Erweiterung für hochgenaue Vakuum-Massekomparatoren : ein Konzeptnachweis. - In: Messunsicherheit praxisgerecht bestimmen – Prüfprozesse in der industriellen Praxis 2023, (2023), S. 17-28

Im Rahmen dieser Arbeit wird eine technische Umsetzung zur Bestimmung der Masse nach der neuen Definition des Internationalen Einheitensystems (SI) von 2019 beschrieben. Als Grundlage dient ein handelsüblicher Hochvakuum Prototyp Massekomparator der Firma Sartorius. Mit Massekomparatoren wurden Kilogramm Prototypen, wie das Urkilogram (ℜ), mit anderen Kilogramm Massenormalen direkt verglichen, um eine Kalibrierkette zu realisieren. Nach der Neudefinition des SI im Jahr 2019 ist das Kilogramm über die Planck-Konstante (h) definiert. Die hier vorgestellte Planck-Erweiterung soll es ermöglichen, durch technische Modifikationen und einigen Zusatzkomponenten, Hochvakuum-Massekomparatoren so umzubauen, dass sie Kilogramm Prototypen und Massenormale nach der neuen Definition kalibrieren können. Zusätzlich soll dadurch eine durchgehende Kalibrierung von Massenormalen im Bereich von 1 mg bis 1 kg nach dem E1-Standard der OIML R 111-1 (2004) ermöglicht werden. Gleichzeitig bleiben alle Funktionen der Massekomparatoren erhalten, wodurch es möglich ist Messungen nach der alten und der neuen Massendefinition miteinander zu vergleichen. Im Verlauf dieser Ausarbeitung wird das Funktionsprinzip der Planck-Erweiterung beschrieben. Weiterhin werden Messergebnisse aus ersten Testmessungen mit einer relativen Standardabweichung von 0,65 ppm gezeigt, analysiert und bewertet. Anhand der Erfahrungen mit der ersten Prototyp-Planck-Erweiterung werden Verbesserungsmöglichkeiten und zukünftige Arbeiten vorgeschlagen.



https://doi.org/10.51202/9783181024287-17
Pabst, Markus; Fröhlich, Thomas; Hilbrunner, Falko
Planck extension for high-precision vacuum mass comparators. - Ilmenau : TU Ilmenau, Universitätsbibliothek, ilmedia. - 1 Online-Ressource (Seite 1-10)Final author's version of the article submitted to the following conference: Understanding climate change through metrology : proceedings of the 2023 NCSL International Workshop & Symposium, July 8-12, 2023, Orlando, Florida. - Lafayette, Colorado : NCSL International, 2023

This paper describes a technical implementation for the realization of the kilogram according to the new definition of the International System of Units (SI) of 2019. A commercially available high-vacuum prototype mass comparator from Sartorius serves as the basis. Mass comparators were used to directly compare kilogram prototypes, such as the International Prototype of the Kilogram (IPK or ℜ), with other kilogram prototypes to realize a calibration chain. Since the redefinition of the SI in 2019, the kilogram is defined by Planck's constant (ℎ). The Planck extension presented here is intended to make it possible, through technical modifications and some additional components, to convert high-vacuum mass comparators so that they can calibrate kilogram prototypes and mass standards according to the new definition. In addition, this should allow the continuous calibration of mass standards up to 1 kg in accordance with the E1 standard of OIML R 111-1 (2004). At the same time, all functions of the mass comparators are retained, which makes it possible to compare measurements according to the old and the new mass definition. During this elaboration, the functional principle of the Planck extension is described. Furthermore, measurement results from initial test measurements of 100 g with a relative standard deviation of 0.68 ppm are presented, analyzed, and evaluated. Based on the experience with the first prototype Planck extension, possible improvements and future work are proposed.



https://doi.org/10.22032/dbt.59125
Shmagun, Vitalii; Gerhardt, Uwe; Manske, Eberhard; Fröhlich, Thomas; Kissinger, Thomas
Resolution enhancement in Fabry-Perot interferometers through evaluation of multiple reflection using range-resolved interferometry. - In: Engineering for a changing world, (2023), 1.1.104, S. 1-8

This work presents a novel approach for improving interferometer resolution with a relatively simple setup by combining the use of range-resolved interferometry and a high-finesse Fabry-Perot setup utilizing multiple reflections in the cavity to gradually increase the resolution. This approach could enable the measurement of small displacements with a potentially much higher resolution than current interferometry methods. A simple proof-of concept setup demonstrated the evaluation of up to four Fabry-Perot passes, while theoretically much higher sensitivity improvement factors should be possible.



https://doi.org/10.22032/dbt.58695