Conceptual design of a microscale balance based on force compensation. - In: Microactuators, microsensors and micromechanisms, (2021), S. 103-114
Macroscopic electromagnetic force compensation (EMFC) balances are well established but were not yet demonstrated within microsystems. Hence, in this paper, the concept and the design of a micro fabricated force compensation balance is presented. The implemented concentrated compliance mechanism in form of flexure hinges enables motion with high precision, which is combined with a force compensation mechanism. The concept of force compensation promises a high measurement range, which is expected to be up to 0.5 mN, while still enabling a high resolution of less than 8 nN. The developed dynamic model of the miniaturized balance is used for the design of a PID-controller strategy. Here, continuous and time-discrete controller approaches are compared. The time-discrete controller with realistic delay times, leads to an accuracy of the controller, which is better than the expected accuracy of the integrated capacitive position sensor.
https://doi.org/10.1007/978-3-030-61652-6_9
Topology optimization of magnetoelectric sensors using Euler-Bernoulli beam theory. - In: Microactuators, microsensors and micromechanisms, (2021), S. 115-124
A studied magnetic field sensor is based on resonant operation of magnetoelectric micro-electro-mechanical systems (MEMS). Subsequently to an applied magnetic field, the micro beam changes the eigenfrequency, due to the magnetostrictive effect. Euler-Bernoulli beam theory can calculate eigenfrequencies of bending vibrations of beams with high accuracy. Implementing more complex beam geometries is challenging, thus often the finite element method (FEM) is used. This paper deals with the modeling of prestressed beams with multilayered structure and discontinuities along the beam length using Euler-Bernoulli beam theory. The arising problems are addressed in detail. As an example, the model is applied to the studied magnetoelectric sensor and shows good accordance to FEM simulations. An optimization algorithm is used to find a sensor geometry that leads to high output signals utilizing the developed model as input for the minimization of a target function.
https://doi.org/10.1007/978-3-030-61652-6_10
Adapted Process Model for Manufacturing Within Production Networks. - In: Production at the leading edge of technology, (2021), S. 611-620
The paper concentrates on the external elimination of bottlenecks by using congruent shared capacities within a non-hierarchical organized network. The study assumes that the capacity of assembly can be adapted by increasing the resources of the company. Conversely, the capacity of production is restricted by technological requirements and regulated by machine resources.To relieve capacity by external measures within a non-hierarchical organized network, an adapted process model is required. For this purpose, critical issues for the process flow within a network are identified and necessary regulations suggested.The paper presents the possibility of integrating the adapted approach into the operations management process as well as into systems of production planning and control and deduces the necessary information that is required to ensure the economic viability of bottleneck removal.
An electrothermally actuated membrane as oscillating pinhole for the high-frequent modulation of light. - In: DGaO-Proceedings, ISSN 1614-8436, Bd. 121 (2020), B37, insges. 2 S.
We present theory, processing steps and first results for a thermally actuated Aluminiumnitride-Platinum membrane with a resonant frequency of the first mode at around 100 kHz and resonant displacements at its center of around 30 µm. The radial-symmetric membrane is broadband opaque for wavelengths from visual light and beyond. An exception is a small pinhole of various diameters below 3 µm in its center. Through thermally induced asymmetric stress inside the multilayer, the clamped membrane bends out. The pinhole in its center will be displaced parallel to the optical axis.The intended use for such a membrane is to replace the traditional confocal pinhole in the detection path of a microscope. Applying a stable known resonant modulation on an acquired signal enables a lock-in principle for a differential confocal depth sensing as shown in [1]. The advantage over the employed tunable acoustic gradient lens (TAG lens) there, is the reduced size, the simplicity of the arrangement and constant illumination properties on the sample.
https://nbn-resolving.org/urn:nbn:de:0287-2020-B037-6
Application of a mobile measuring device for the planar evaluation of the current in-situ stress condition in glass. - Delft : TU Delft Open. - 1 Online-Ressource (11 Seiten)Online-Ausgabe: Challenging Glass 7 : Conference on Architectural and Structural Applications of Glass, Ghent University, September 2020 / editors Jan Belis (Ghent University, Ghent, Belgium), Freek Bos (Eindhoven University of Technology, Eindhoven, the Netherlands), Christian Louter (Technische Universität Dresden, Dresden, Germany). - Delft : TU Delft Open, 2020. - ISBN 978-94-6366-296-3
The load-bearing capacity of glass as a structural material as well as sustainability and resistance of a built-in glass against appearing loads and forces is assuming an ever-greater importance. Next to analytical and numerical calculations of maximum load-bearing capacity and the ultimate limit state, there is no generally accepted standardized non-destructive inspection method available, with which it is possible to estimate the prevalent load situation and predominant stress conditions, particularly in relation to mechanical or adhered connections. Within the research project “BiGla”, a measuring instrument based on photoelasticity was developed, which enables to measure and monitor occurring load states during the installation process, as well as the utilization of glass components subjected to significant load changes during their life cycle. Based on the combined examination of photoelasticity and its synergism with the finite element analysis it becomes possible to transfer qualitative measurement results into quantitative evaluations of predominant stress conditions. Achieved results, gained during experimental investigations under laboratory conditions, as well as during extensive field tests, are presented in this publication.
https://doi.org/10.7480/cgc.7.4487
Additive manufactured injection moulds with optical quality surfaces. - In: Proceedings of the 20th International Conference of the European Society for Precision Engineering and Nanotechnology, (2020), S. 147-150
Deformed microcavities with very high Q-factors and directional farfield emission. - In: EOS Annual Meeting (EOSAM 2020), (2020), 01006, S. 1-2
We report the design and optimized fabrication of deformed whispering gallery mode resonators in silica with solely ICP-RIE. This allows us to control the morphology of the resonators more freely and results in low surface roughness. The light was coupled into the resonator using a state of the art tapered fiber approach and we determined the Q-factor in the range of 10^5
https://doi.org/10.1051/epjconf/202023801006
Fast reaction screening combining segmentet flow microfluidics and surface enhanced Raman spectroscopy. - In: 23rd International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2019), (2020), S. 1368-1369
Vorstellungsvermögen und handwerkliche Fertigkeiten: Moodle-Vorbereitungskurs "Technische Darstellungslehre". - In: Technische Bildung im Kontext von 'Digitalisierung'/'Automatisierung' - Tendenzen, Möglichkeiten, Perspektiven, (2020), S. 167-170
Self-aligning ruthenium interconnects. - In: 2020 IEEE International Interconnect Technology Conference (IITC), (2020), S. 82-84
This contribution shows self-aligning ruthenium interconnects. The underlying process is gas phase electrodeposition, which allows metallic particles to be deposited locally. This is performed with an adjustable airgap between the insulator and the deposited metallic structure. The size of the enclosed airgap can be adjusted directly. The deposition power has a direct influence on the growth rate and the morphology of the structure. With increasing deposition power, the resulting self-aligning nano-bridge becomes more compact.
https://doi.org/10.1109/IITC47697.2020.9515654