Zur Massendynamik eines geschlossenen Ökosystems, gemessen mit einem Prototyp Vakuummassekomparator - eine methodische Validierungsstudie :
On mass dynamics in a closed ecological system, determined with a prototype vacuum mass comparator - a methodological validation study. - In: Technisches Messen, ISSN 2196-7113, Bd. 90 (2023), 2, S. 127-137
The aim of this work was to validate a novel methodology for high-resolution, repetitive measurements of mass dynamics of biological processes and structures in a closed plant-earth ecosystem consisting of Mammillaria vetula and microorganisms. To perform these experiments, the living system was materially welded into a newly developed Titanium Weighing Hollow Body (TWHB) with a laser. Three non-vital, also hermetically welded and high-vacuum suitable, externally identical TWHBs, filled with sand, served as controls. All TWHBs were equipped with a feedthrough and integrated light source. LEDs generated continuous light in all four bodies, which drove the photobiological processes in the vital test body and allowed long-term growth. Mass differences of the TWHBs were measured with a vacuum mass comparator at four points in time three months apart against two stainless steel mass standards. The expanded measurement uncertainty of the mass increase of the vital TWHB was calculated according to the Guide to the Expression of Uncertainty in Measurement (GUM) in each of the three independent experiments. The mass gain of the vital over the three nonvital TWHBs over the total experimental period of 9 months was +18 μg with the expanded measurement uncertainty 30 μg. The resulting mass gain would have had to be > 48 μg to be considered statistically significant with a confidence level of 97.7%; time intervals over three and six months were also not significant. The study validates for the first time a methodology capable of measuring mass dynamics of living matter over time, when statistically sound conclusions with measurement uncertainties in the microgram range are required. This opens up a new level of precision mass measurements, which makes the methodology a candidate, e.g., for the verification of the principle of mass conservation in the life-sciences.
https://doi.org/10.1515/teme-2022-0086
Einsatz von gepulsten Lasern mit hoher Leistung in der Präzisionskraftmesstechnik - ein Schritt in die Richtung einer künftigen, SI-rückführbaren und praktischen Kraftquantisierung durch Photonenimpulse :
Deploying the high-power pulsed lasers in precision force metrology - towards SI traceable and practical force quantization by photon momentum. - In: Technisches Messen, ISSN 2196-7113, Bd. 89 (2022), 11, S. 757-777
Design and operational performance of table-top measurement apparatus is presented towards direct Planck constant traceable high accuracy and high precision small forces and optical power measurements within the SI unit system. Electromagnetic force compensation weighing balances, highly reflective mirrors and high-energy pulsed laser unit (static average power 20 W) are tailored together with a specially developed opto-electro-mechanical measurement infrastructure for cross-mapping the scale-systems of two different precision small force measurement methods. One of these methods obtains the force measurements by a state-of-the-art classical kinematic system employing the partial use of Kibble balance principle in the range of 10 nN to 4000 nN to be compared with forces generated due to quantum-mechanical effect namely the transfer of the momentum of photons from a macroscopic object. Detailed overview of the adapted measurement methodology, the static and the limits of dynamic measurement, the metrological traceability routes of the measurement parameters, quantities and their measurement uncertainties, parametric estimation of up (down)-scaling perspectives of the measurements are presented with respect to the state-of-the-art measurement principles and standard procedures within the newly redefined International System of Units (SI).
https://doi.org/10.1515/teme-2022-0080
Absolute distance measurements for in-situ interferometer characterisation using range-resolved interferometry. - In: Measurement science and technology, ISSN 1361-6501, Bd. 33 (2022), 12, 125024, S. 1-12
Range-resolved interferometry (RRI) allows the simultaneous demodulation of multiple interferometric signal sources and provides a tomographic view of all constituent interferometers that may be present in a setup. Through comparison with a reference distance of known length, absolute distance measurements can be performed. RRI is tailored to the use of laser frequency modulation through injection-current modulation of regular, monolithic laser diodes that are both cost-effective and highly coherent and therefore this approach promises broad applicability. In this paper, two methods for absolute distance measurement, one based on the direct evaluation of the signal peak positions and one based on the phase demodulation of an additional lock-in modulation signal, are experimentally demonstrated. Using an external verification displacement interferometer, both techniques are shown to achieve in-situ absolute distance measurements with systematic errors below over a 50 mm travel range. The aim of this paper is to establish the general suitability of RRI for absolute distance measurements and in-situ tomographic interferometer characterisation for precision engineering. In future, this approach could be used to diagnose interferometric setups for parasitic signal contributions, multiple reflections or to determine the dead path length for accurate environmental compensation, either for use during initial setup of, or for continuous operation alongside, a regular displacement measuring interferometer.
https://doi.org/10.1088/1361-6501/ac970a
Formation and characterization of three-dimensional tetrahedral MoS2 thin films by chemical vapor deposition. - In: Crystal growth & design, ISSN 1528-7505, Bd. 22 (2022), 9, S. 5229-5238
A method to synthesize the three-dimensional arrangement of bulk tetrahedral MoS2 thin films by solid source chemical vapor deposition of MoO3 and S is presented. The developed synthesizing recipe uses a temperature ramping with a constant N2 gas flow in the deposition process to grow tetrahedral MoS2 thin film layers. The study analyses the time-dependent growth morphologies, and the results are combined and presented in a growth model. A combination of optical, electron, atomic force microscopy, Raman spectroscopy, and X-ray diffraction are used to study the morphological and structural features of the tetrahedral MoS2 thin layers. The grown MoS2 is c-axis oriented 2H-MoS2. Additionally, the synthesized material is further used to fabricate back-gated field-effect transistors (FETs). The fabricated FET devices on the tetrahedral MoS2 show on/off current ratios of 10^6 and mobility up to ∼56 cm^2 V^-1 s^-1 with an estimated carrier concentration of 4 × 10^16 cm-3 for VGS = 0 V.
https://doi.org/10.1021/acs.cgd.2c00333
Conference measurement uncertainty Erfurt 2021 :
Tagung Messunsicherheit Erfurt 2021. - In: Technisches Messen, ISSN 2196-7113, Bd. 89 (2022), 10, S. 645-646
https://doi.org/10.1515/teme-2022-0088
A novel concept for 5D nanopositioning, nanomeasuring and nanofabrication machines :
Ein neuartiges Konzept für 5D Nanopositionier-, Nanomess-, und Nanofabrikationsmaschinen. - In: Technisches Messen, ISSN 2196-7113, Bd. 89 (2022), 9, S. 634-643
In den vergangenen Jahren wurden an der TU-Ilmenau zahlreiche Entwicklungen im Bereich der Nanopositionier- und Nanomesstechnik realisiert. Insbesondere die NMM-1 [Gerd Jäger, Eberhard Manske, Tino Hausotte, Jans-Joachim Büchner, Nanomessmaschine zur abbefehlerfreien Koordinatenmessung, tm - Technisches Messen, 67(7-8), 2000] sowie die NPMM-200 [Eberhard Manske, Gerd Jäger, Tino Hausotte, Felix Balzer, Nanopositioning and Nanomeasuring Machine NPMM-200 - sub-nanometre resolution and highest accuracy in extended macroscopic working areas, euspen’s 17th International Conference, 2017] stellen ein Novum auf dem Gebiet der Koordinatenmesstechnik mit Nanometerpräzision unter Einhaltung des Abbe-Komparatorprinzips [Ernst Abbe, Messaparate für Physiker, Zeitschrift für Instrumentenkunde, 10:446-448, 1890] dar. Ausgehend von diesen Errungenschaften besteht ein nächster Schritt im Messen und Fabrizieren auf stark gekrümmten, asphärischen, oder freigeformten Oberflächen. Vor jenem Hintergrund wird im folgenden Artikel ein Konzept für ein zweiachsiges Rotationsmodul vorgestellt. Dieses dient als Erweiterung für die NMM-1 und ermöglicht über das kartesische Messvolumen von hinaus zusätzlich eine Rotation des Tools über 360 ˚ um die Hochachse sowie 60 ˚ Neigung. Die Umsetzung erfolgt über eine neuartige sphärische Parallelkinematik. Mit Hilfe eines interferometrischen In-Situ-Referenzmesssystems können die während der Rotationsbewegungen auftretenden translatorischen Positionsabweichungen detektiert werden. Erste Untersuchungen an einem Prototypenaufbau erbringen den Funktionsnachweis des Referenzmesssystems über den gesamten adressierbaren Winkelbereich.
https://doi.org/10.1515/teme-2022-0037
Measurement precision of a planar nanopositioning machine with a range of motion of Ø100 mm. - In: Applied Sciences, ISSN 2076-3417, Bd. 12 (2022), 15, 7843, S. 1-14
This work deals with various investigations into the accuracy of a newly developed planar nanopositioning machine. This machine, called Nanofabrication Machine 100 (NFM-100), has a positioning range of 100 mm in diameter. To determine the precision, various movement scenarios are performed with the machine table, and the trajectory deviation from the set trajectory is determined. In particular, the focus is on high velocities of up to 20 mm/s. Even at high speeds in the range of several millimetres per second, this machine can impress with its performance and only has a deviation in the nanometre range.
https://doi.org/10.3390/app12157843
Design of compliant mechanisms based on rigid-body mechanisms. - In: Romanian journal of technical sciences, ISSN 2601-5811, Bd. 67 (2022), 1, S. 61-78
The design of compliant mechanisms is a much more complicated task than their analysis. Consequently, there are many more methods available for the analysis of compliant mechanisms than for their synthesis. In this article, a contribution to the synthesis of compliant mechanisms is made by presenting a comparison of two different methods for their design. In both methods rigid-body systems are used as a basis for compliant mechanisms. Depending on the task of the compliant mechanism, one of these methods can be selected and applied. The deviations between the results of the used theory and measurement results as well as FEM results are less than 5.5 % for displacements and acting forces. Selected mechanisms for the realization of a straight-line motion of a point and for given relative motions are presented as examples.
Adjustment concept for compensating for stiffness and tilt sensitivity of a novel monolithic electromagnetic force compensation (EMFC) weighing cell. - In: Journal of sensors and sensor systems, ISSN 2194-878X, Bd. 11 (2022), 1, S. 109-116
This paper describes the new adjustment concept of novel planar, monolithic, high-precision electromagnetic force compensation weighing cells. The concept allows the stiffness and the tilt sensitivity of the compliant mechanisms that are dependent on the nominal load on the weighing pan to be adjusted to an optimum. The new mechanism is set up and adjusted according to the developed mechanical model. For evaluation of the concept the system is tested on a high-precision tilt table and under high vacuum conditions in the environment of a commercially available mass comparator.
https://doi.org/10.5194/jsss-11-109-2022
Sensor and Measurement Science International Conference 2021. - In: Technisches Messen, ISSN 2196-7113, Bd. 89 (2022), 1, S. 1-3
https://doi.org/10.1515/teme-2021-0116