tm - Technisches Messen最新文献

{"title":"Untersuchung der piezoresistiven Eigenschaften in carbonfaserverstärkten Elektroden von dielektrischen Elastomeraktoren","authors":"Markus Koenigsdorff, Johannes Mersch, G. Gerlach","doi":"10.1515/teme-2024-0002","DOIUrl":"https://doi.org/10.1515/teme-2024-0002","url":null,"abstract":"\u0000 Die weiche Robotik ist ein sich schnell entwickelnder Bereich, und dielektrische Elastomeraktoren (DEAs) haben sich als vielversprechend im Bereich der Aktorkonzepte herausgestellt. Ein neuartiger Ansatz zur Steigerung der Kraftwirkung der DEAs besteht darin, anisotrope Schichten, wie beispielsweise Fasern, in die Aktoren zu integrieren. Insbesondere Carbonfasern zeichnen sich durch ihre hohe Steifigkeit und elektrische Leitfähigkeit aus und dienen nicht nur als effektive Verstärkung, sondern können auch als Material für die Elektroden der Aktoren genutzt werden. Darüber hinaus lassen sich die Elektroden der DEAs zur Selbstüberwachung nutzen, indem sie zusammen mit dem Dielektrikum als resistive oder kapazitive Sensoren eingesetzt werden. Trotz der verschiedenen Methoden, die für die Implementierung von Sensor- und Regelungsfunktionen vorgeschlagen wurden, gibt es noch eine Lücke im Verständnis der piezoresistiven Eigenschaften von carbonfaserverstärkten DEAs. In dieser Arbeit werden diese für carbonfaserverstärkte und kohlenstoffpartikelbasierte Elektroden untersucht, um den Unterschied zwischen konventionellen und den neuen, verstärkten Elektroden zu vergleichen. Ein wesentliches Ergebnis der Untersuchung ist die unerwartete inverse piezoresistive Kopplung der carbonfaserverstärkten Elektroden nach einem ersten Belastungszyklus. Dieses antipropotionale Dehnungs-Widerstandsverhalten ist im Anschluss über die weiteren Zyklen ebenfalls vorhanden. Darüber hinaus dominiert der geringere spezifische Widerstand der Carbonfasern das gesamte Widerstandsverhalten der Elektroden gegenüber dem reinen, partikelgefüllten Elastomer.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140250584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Textile-based strain sensors for fiber-reinforced composites under tension, compression and bending","authors":"Hung Le Xuan, Chokri Cherif","doi":"10.1515/teme-2023-0146","DOIUrl":"https://doi.org/10.1515/teme-2023-0146","url":null,"abstract":"\u0000 This research addresses the challenging task of monitoring the structural integrity of fiber-reinforced composite (FRC) components under complex loading conditions. Ensuring the safety and functionality of these components is critical but economically challenging. Therefore, this study presents an innovative approach using textile-based strain sensors that are cost-effective and structurally compatible with carbon fiber-reinforced plastic (CFRP) components. The investigation includes the systematic electromechanical characterization and comparison of four different sensor materials at the yarn and composite scale in various test scenarios. Cyclic tensile, compression, and bending tests of CFRP specimens are performed and show good reproducibility of sensor signals within the elastic range, with significant agreement observed with applied strain measurement methods, particularly in tensile tests. Although there are minor deviations in compression and bending evaluations, the signals are still meaningful for in-situ detection of complex loading patterns, crack initiation, and structural failure. The study demonstrates that the integration of textile-based sensor yarns allows for continuous structural health monitoring (SHM) of CFRP components under various loading scenarios, including tensile, bending, and especially compressive loads.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140249949","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temperature-dependent calibration and temperature compensation of elastic shape-memory alloy strain sensors for fiber-reinforced composite applications","authors":"T. Mäder, B. Senf, M. Zoch, Welf-Guntram Drossel","doi":"10.1515/teme-2023-0149","DOIUrl":"https://doi.org/10.1515/teme-2023-0149","url":null,"abstract":"\u0000 Strain sensors for fibre-reinforced plastics require higher elasticity and fatigue resistance than conventional strain gauges. Elastic strain sensors made of shape-memory alloys (SMA) meet this requirement. Due to greater elasticity, other procedures are required for their calibration than those recommended in standards. This paper presents a calibration method for shape-memory strain sensors as a function of ambient temperature and methods for temperature compensation are investigated. SMA strain sensors are manufactured as sensor patches from wire and layers of glass fibre fleece infiltrated with epoxy resin. The patches are bonded to bending specimens made of glass-fibre plastic composites. The calibration of the SMA sensors is implemented by means of a 4-point bending test using a self-built test stand. This is designed for operation in a climate chamber. The results show successful proof of feasibility of temperature compensation. The variation of sensor signal in the unloaded state in the temperature response is less than 0.4 mV/V. The gauge factor depends on the temperature and is compensated by means of a regression with temperature sensor data. In combination with a temperature sensor, an almost complete compensation of the temperature-dependent behaviour is possible. A procedure is realised for calibrating SMA sensors at larger strains.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140251258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using micro spheres as reference artifacts for the in-situ characterization of tactile 3D micro probes along the probing sphere’s equator","authors":"E. Oertel, Eberhard Manske","doi":"10.1515/teme-2023-0164","DOIUrl":"https://doi.org/10.1515/teme-2023-0164","url":null,"abstract":"\u0000 Nano and micro coordinate measuring machines (CMMs) have been developed for the characterization of small dimensional features. They require a procedure which enables a traceable and precise characterization of probing spheres. In this contribution we explore the use of well characterized micro spheres as reference artifacts for the in-situ characterization of probing spheres along the probing sphere’s equator. The spheres are characterized using a strategy which is based on a set of tactile surface scans in conjunction with a stitching-algorithm. These micro spheres serve as a reference for the in-situ characterization of a tactile 3D micro probe on a nano measuring machine (NMM-1). Our investigations are based on a sample of eight spheres sourced from two different suppliers. Although the sample is small, we could already observe characteristics which seem to be typical for spheres of a certain type (i.e. nominal radius and material). The experiments indicate that micro spheres are a suitable reference artifact for tactile 3D micro probes. We were able to reproduce the measured mean radius of the probing sphere with a standard deviation of 31 nm using reference spheres whose nominal radius covers a range of 89 µm.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140252256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Untersuchung der Blasendynamik von Flüssigkeitskavitation im Schmierfilm eines hydrodynamischen Gleitlagers","authors":"Marcus Schmidt, T. Beckmann","doi":"10.1515/teme-2023-0161","DOIUrl":"https://doi.org/10.1515/teme-2023-0161","url":null,"abstract":"\u0000 In hydrodynamischen Gleitlagern kann im Schmierfilm unter gewissen Betriebsbedingungen Flüssigkeitskavitation auftreten. Die Flüssigkeitskavitation lässt sich in drei Kavitationsformen unterscheiden: Pseudo-, Gas- und Dampfkavitation. Lediglich Dampfkavitation kann in Verbindung mit Werkstoffkavitation zum Schaden und später zum Ausfall eines Gleitlagers führen. Eine mögliche Ursache zur Entstehung von Dampfkavitation liegt in der Dynamik der Spaltweitenänderung einer Wellenverlagerungsbahn begründet. Die Autoren haben den erstmaligen Nachweis von implodierenden Dampfblasen im Schmierfilm eines Gleitlagers in Folge einer transienten Spaltweitenänderung vollumfänglich erbracht. Zum Erzeugen der schadensrelevanten Dampfkavitation muss eine kritische Spaltweitenänderungsgeschwindigkeit in Verbindung mit einer kritischen Exzentrizität erreicht werden. Für diese Untersuchungen steht ein Gleitlager-Modellexperiment zur Verfügung, welches kontinuierlich erweitert wurde und so dem Stand der Forschung entspricht. Es ist somit möglich, kavitierende Schmierspaltströmungen sowohl qualitativ als auch quantitativ zu untersuchen. Das Modellexperiment verfügt über eine Aktorik, die eine gezielte Steuerung der Spaltweitenänderungsgeschwindigkeit zulässt und so die Kavitationsbereiche einer realen Wellenverlagerungsbahn abbildet. Das Experiment beinhaltet ein speziell entwickeltes Fluid, dass die Reynolds- und Kavitationsähnlichkeit erfüllt. Bei der Untersuchung von Flüssigkeitskavitation muss sowohl das Verdampfen der Flüssigkeit (Dampfkavitation), das Ausgasen von Luft (Gaskavitation) sowie das Vorhandensein kleinster Luftblasen (Pseudokavitation) experimentell abgebildet werden. Dies wird u. a. durch die Verwendung von konditionierten Flüssigkeiten realisiert. Abhängig vom Betriebspunkt des Gleitlagers, treten die drei Kavitationsformen separat als auch in Verbindung miteinander auf. Das gleichzeitige Auftreten reduziert, je nach Anteil der Kavitationsformen, die Kavitationserosion, indem sie die schädigungsrelevante Dampfkavitation dämpft. Das übergeordnete Forschungsziel ist es einen Parameterbereich zu definieren, in dem eine kritische Spaltweitenänderung mit einer kritischen Exzentrizität zur „reinen“ Dampfkavitation führt. Damit soll der schadenskritische Parameterbereich eingegrenzt werden. Dies soll zukünftig bei der Auslegung und Parametrisierung von hydrodynamischen Gleitlagern helfen. Die gezeigten experimentellen Ergebnisse umfassen Hochgeschwindigkeitsaufnahmen, die eine detaillierte Analyse der Blasenbildung mit einer Geschwindigkeit von 10.000 Bildern pro Sekunde (fps) ermöglichen. Es lässt sich zusammenfassen, dass die Arbeit ein tieferes Verständnis für den Kavitationsprozess in dynamisch belasteten Gleitlagern erbringt. Das Forschungsvorhaben wurde gefördert durch die Deutsche Forschungsgemeinschaft (DFG) unter der Projektnummer 462581008.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140253308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distributed fiber optic sensors for structural health monitoring of composite pressure vessels","authors":"Christos Karapanagiotis, M. Schukar, Katerina Krebber","doi":"10.1515/teme-2023-0170","DOIUrl":"https://doi.org/10.1515/teme-2023-0170","url":null,"abstract":"\u0000 In this paper, we present a comprehensive overview of our research in the field of distributed fiber optic sensors for structural health monitoring of hydrogen composite pressure vessels. Specifically, we demonstrate how the integration of fiber optic sensors into composite pressure vessels enhances safety while simultaneously reducing maintenance costs. The small size of optical fibers enables their integration into composite structures during the manufacturing process, allowing continuous monitoring and precise detection and localization of structural damages during service life. We also discuss the potential of state-of-the-art signal processing methods and machine learning for advancing predictive maintenance. Our applications of fiber optic sensors demonstrate their potential to contribute significantly to the energy transition towards renewable sources.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140076802","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preprocessing method for robust topography reconstruction of surfaces of metal additive manufactured parts based on focus variation microscopy","authors":"Xin Xu, T. Pahl, H. Serbes, P. Krooss, Thomas Niendorf, Peter Lehmann","doi":"10.1515/teme-2023-0157","DOIUrl":"https://doi.org/10.1515/teme-2023-0157","url":null,"abstract":"\u0000 When using an areal measuring optical instrument to measure rough surfaces, especially surfaces generated by metal additive manufacturing (e.g. laser and electron beam powder bed fusion), topographical artifacts such as spikes on a reconstructed surface are nearly unavoidable. These artifacts may affect the determination of surface roughness parameters and lead to erroneous surface features. This paper proposes a new preprocessing method to eliminate most artifacts before extracting surface heights of rough surfaces measured by focus variation microscopy. In this method, the axial region where a surface height value is located with the highest probability is estimated, based on datasets of planes parallel to the axial scanning direction. Results regarding height measurements with and without the preprocessing method are compared by measuring a Rubert Microsurf 329 comparator test panel for reference and workpieces produced by metal additive manufacturing.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140257305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gesture and force sensing based on dielectric elastomers for intelligent gloves in the digital production","authors":"S. Gratz-Kelly, Daniel Philippi, Bettina Fasolt, S. Nalbach, Paul Motzki","doi":"10.1515/teme-2024-0003","DOIUrl":"https://doi.org/10.1515/teme-2024-0003","url":null,"abstract":"\u0000 Due to recent progress in human-machine interaction the development of interfaces ensuring a safe collaboration between handling devices and workers is gaining in importance and impact to the industry field. For an adequate operation, combined sensing and actuation capabilities are sufficient for interaction units. Smart materials like dielectric elastomers (DEs) are predestinated for integrated multi-functional applications. DEs are lightweight, high energy density and highly stretchable transducers suitable for many different operation areas, like movement tracking, force sensing, haptic feedback and sound generation and can be used to develop highly integrated textile-based user interfaces. This paper shows first results on the development of a novel intelligent glove prototype based on DE elements. The main focus of this investigation lies on DE-based integrated joint angle and force measurement units as well on a cost-efficient and slim sensing electronic. By embedding the resulting system in an industry 4.0 environment, an adaptive assistance tool can be developed. The resulting system can be used to monitor the desired motion of a worker and to respond with a corresponding haptic feedback, which depends on the specific interaction task. This makes the resulting system a novel, portable assistant tool for industrial environments.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140079858","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fault diagnosis using signal processing and deep learning-based image pattern recognition","authors":"Zhenxing Ren, Jianfeng Guo","doi":"10.1515/teme-2023-0089","DOIUrl":"https://doi.org/10.1515/teme-2023-0089","url":null,"abstract":"Abstract The vibration signal is a typical non-stationary signal, making it challenging to use traditional time-frequency analysis techniques for fault diagnosis. Therefore, this work investigates the processing of vibration signals and proposes a deep learning method based on processed signals for the fault diagnosis of ball bearings. In this work, the fault diagnosis is formulated as an image classification problem and solved with deep learning networks. The intrinsic mode functions (IMFs), converted from the vibration signals in the time domain, are then transformed into symmetrized dot pattern (SDP) images. In order to increase classification accuracy, the SDP parameters in this study are chosen by optimizing image similarity. The feasibility and accuracy of the proposed approach are examined experimentally.","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139437393","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Erratum to: Potentials and challenges of deep-learning-assisted porosity prediction based on thermographic in-situ monitoring in laser powder bed fusion","authors":"Simon Oster, Nils Scheuschner, Keerthana Chand, S. Altenburg, Gerald Gerlach","doi":"10.1515/teme-2023-0166","DOIUrl":"https://doi.org/10.1515/teme-2023-0166","url":null,"abstract":"","PeriodicalId":509687,"journal":{"name":"tm - Technisches Messen","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139437374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}