TY - CONF A1 - Schukar, Vivien A1 - Köppe, Enrico A1 - Hofmann, Detlef A1 - Westphal, Anja A1 - Sahre, Mario A1 - Beck, Uwe A1 - Gong, Xing A1 - Bartholmai, Matthias ED - Aulova, Alexandra ED - Rogelj Ritonja, A. ED - Emri, I. T1 - A contribution to intelligent automatic validation of structure-integrated fibre optic strain sensors N2 - Sensors integrated into devices and structures provide essential data to control, optimize or manage machines and structural components. In the last years, processes, applications and machine parts became more and more intelligent. Consequently, the need for sensor validation increased significantly in order to rely on sensor data and measurement results. Structure-integrated fibre optic strain sensors, such as fiber Bragg gratings (FBG), are of special interest in the composite manufacturing industry. This type of sensor makes it possible to gain information and to collect measurement data about entire production processes and whole life-time cycles of composite-made machine parts and structures. However, validation concepts and approaches for this type of sensors are barely reported in literature. Furthermore, all the reported activities have the drawback that the sensor diagnosis strategy is implemented as limited mathematical models and/or complex time-consuming spectral analysis tools which are applied in data post-processing loops. However, to automate sensor validation and to apply real-time and in-field sensor fault detection, it is necessary to acquire measurement data and information about the measurement reliability at the same time. T2 - 33rd Danubia- Adria Symposium on Advances in Experimental Mechanics CY - Portorož, Slovenia DA - 20.09.2016 KW - Fiber bragg grating KW - Magnetic field KW - Magnetostrictive metal coating KW - Self-diagnostic fiber optical sensor PY - 2016 SN - 978-961-94081-0-0 SP - 180 EP - 181 CY - Ljubljana AN - OPUS4-37645 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schukar, Vivien A1 - Köppe, Enrico A1 - Hofmann, Detlef A1 - Mitzkus, Anja A1 - Gong, Xin A1 - Sahre, Mario A1 - Bartholmai, Matthias A1 - Beck, Uwe ED - Emri, Igor T1 - A contribution to intelligent automatic validation of structure-integrated fibre optic strain sensors N2 - An auto-validation tool for the reliability quantification of materials integrated fiber Bragg grating (FBG) strain sensors have been developed and tested. The FBG strain sensor was jacketed with a magnetostrictive layer based on iron-nickel which, when excited by a specific magnetic field, adds an artificial strain to the sensor. The fixed relationship between magnetic induction and wavelength shift of the FBG strain sensor characterizes the bond strength and adhesion between the sensor and the surrounding structure. Due to an easily applicable magnetic field, it is possible to validate the sensor performance in a non-contact, fast way without disturbing the data-acquisition process. T2 - 33nd Danubia Adria Symposium on Advances in Experimental Mechanics CY - Portorož, Slovenia DA - 20.09.2016 KW - Fiber Bragg grating KW - Self-diagnosis KW - Magnetostriction KW - Strain KW - Auto-validation PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S2214785317308489 U6 - https://doi.org/10.1016/j.matpr.2017.06.073 SN - 2214-7853 VL - 4 IS - 5, Part 1 SP - 5935 EP - 5939 PB - Elsevier Ltd. AN - OPUS4-41583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Schukar, Vivien A1 - Bartholmai, Matthias A1 - Beck, Uwe T1 - Abschlussbericht zum DFG-Projekt „FAMOS²“ FAser-basierter Magneto-Optischer SchichtSensor N2 - Der Mangel an Anwendungsrichtlinien und Validierungsverfahren für struktur-eingebettete faseroptische Dehnungssensoren, insbesondere auf Faser-Bragg-Gitter (FBG)-Basis, führte bislang dazu, dass diese Sensoren trotz ihrer hervorragenden Eigenschaften im Bereich der kommerziellen Material- und Strukturüberwachung nur in geringem Umfange eingesetzt wurden. Fragen zur Degradation der Sensoren unter Beanspruchung, Alterung durch klimatische Einflüsse und Enthaftung infolge Belastung der Struktur konnten bisher nur theoretisch simuliert oder anhand exemplarischer Proben für einzelne einflussnehmende Parameter im Labor untersucht werden. Die Erfassung des Sensorverhaltens im Bauteil unter komplexen Umwelteinflüssen während des Bauteilbetriebes, um damit eine Aussage zur Zuverlässigkeit der Sensormessdaten zu gewinnen, war bisher nicht möglich. Im Forschungsprojekt FAMOS² wurde deshalb von 2014 bis 2018 die Realisierung eines Autodiagnoseverfahrens für faseroptische Dehnungssensoren erarbeitet, um die Funktionszuverlässigkeit und Langzeitstabilität der Sensoren während des Bauteilbetriebes innerhalb einer Bauteilstruktur bewerten zu können. Im Rahmen des Forschungsprojektes wurde gezeigt, dass ein FBG-Sensor mit einer speziell angepassten magnetostriktiven Schicht magnetisch so angeregt werden kann, dass mit einer zugeschnittenen Messmethodik zu jedem Zeitpunkt eine Bewertung der Sensorzuverlässigkeit unter Betriebsbedingungen möglich ist. Die auf den Sensor aufgebrachte magnetostriktive Schicht erzeugt bei Anregung mit einem passenden Magnetfeld eine gepulste, synthetische Dehnung. Diese Dehnung steht in einem definierten Verhältnis zum anregenden Magnetfeld und wird optisch über die Verschiebung der Bragg-Wellenlänge ausgelesen. Die Konstanz dieses Verhältnisses stellt dann ein Maß für die korrekte Funktionsfähigkeit des Sensors dar. Das Beschichtungs-verfahren, das magnetische Anregungs- und optische Ausleseverfahren, wie auch die Validierung des Sensors unter Berücksichtigung faseroptischer Effekte wurden während des Projekts konzeptionell entwickelt, aufgebaut und charakterisiert. Qualitativ kann mit diesem Verfahren zunächst eine Gut-/Schlecht-Beurteilung des Sensors vorgenommen werden. Perspektivisch bietet das Verfahren jedoch auch die Möglichkeit, verschiedene Versagensmechanismen bestimmen und klassifizieren zu können. Es zeichnete sich schon während des Projektverlaufs ab, dass sich aus den erzielten Ergebnissen über das Autodiagnoseverfahren hinaus weitere Anwendungsmöglichkeiten für den Einsatz des kombinierten magnetostriktiv-faseroptischen Sensorprinzips, beispielsweise als reiner Magnetfeldsensor, ergeben. Nach Abschluss dieses Forschungsprojekts besteht nun die Möglichkeit, den Funktionszustand faseroptischer Dehnungssensoren jederzeit unabhängig von Alter, Belastung oder Kenntnis eines Referenzzustands zu einem bestimmten Zeitpunkt bestimmen zu können. Aufbauend auf diesen Ergebnissen können weiterführende Forschungen die Messmethodik vertiefend charakterisieren und weitere Anwendungsfälle erschließen. KW - Faser-Bragg-Gitter (FBG) KW - Sensorvalidierung KW - Magnetostriktive Beschichtung KW - Structural Health Monitoring (SHM) PY - 2018 N1 - Das Dokument unterliegt der Vertraulichkeit und kann nicht zugänglich gemacht werden - Projektlaufzeit: 01.04.2014 - 31.07.2018 The document is subject to confidentiality restrictions and cannot be made accessible - project runtime: 01.04.2014 - 31.07.2018 SP - 1 EP - 28 AN - OPUS4-50418 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mitzkus, Anja A1 - Sahre, Mario A1 - Reinstädt, Philipp A1 - Griepentrog, Michael A1 - Beck, Uwe A1 - Köppe, Enrico A1 - Bartholmai, Matthias A1 - Basedau, Frank A1 - Hofmann, Detlef A1 - Gong, Xin A1 - Schukar, Vivien T1 - Altbekannter Watts-Elektrolyt, junge Hightech-Anwendung, Nickel- und Nickel-Eisen-Schichten als magnetostriktive Aktorschicht auf faseroptischen Sensoren N2 - Durch faseroptische Sensoren können Bauteile im Einsatz kontinuierlich überwacht und frühzeitig Informationen über Materialveränderungen gewonnen werden. Mittels einer magnetostriktiven Aktorschicht, welche den Sensor umhüllt, kann nun auch die korrekte Sensorfunktion jederzeit kontrolliert werden. Als Aktorschicht eignet sich galvanisch abgeschiedenes reines Nickel oder Nickel-Eisen in der Zusammensetzung 50:50. Um diese haftfest mit dem Sensor zu verbinden wurde ein ECD/PVD-Kombinationsschichtsystem entwickelt. Die mechanischen Eigenschaften der ECD-Schicht können sowohl mit einer auf die Fasergeometrie angepassten instrumentierten Eindringprüfung als auch einem 2-Punkt-Biegeversuch bestimmt werden. KW - Faseroptik-Sensoren KW - ECD-Aktorschicht KW - PVD-Haftfestigkeit KW - Nickel-/Nickel-Eisen- Magnetostriktion PY - 2016 SN - 2195-5891 SN - 2195-5905 VL - 12 SP - 1 EP - 4 AN - OPUS4-39129 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Schukar, Vivien A1 - Kusche, Nadine T1 - Calibration facility for quality certification of surface-attached fiber optic and electrical strain sensors N2 - Strain measurement in structures witli the purpose of long-term structurai health inonitoring must provide reliable inforination about the structure’s behavior over the whole period of use. The user must be sure that installed sensors are validated and work to the utmost satisfactiou. For this purpose, sensor Systems are tested using special facilities. Bccause it is not easy to characterize the strain transfer quality from the host structure into surface-applied strain sensors, a unique testing facility has been developed. Originally developed for fiber Bragg grating based sensors, the KALFOS facility (= calibration of fiber optic sensors) can also be used for electrical strain sensors. Calibration ineasurements are referenced by unbinsed Digital Image Correlation (D1C) and Electronic Speckle Pattern Interferometer (ESPI) methods. The strain transfer behavior can experimentally be analyzed and investigated under combined thermal and mechanical loading conditions and allows revealing wealuiesses in couimonly used attachment methodologies. The deformation of all members (particularly the coating/substrate - adhesive combination) in the sensing area is physically independently gained and recorded. Results achievcd allow precise description of the strain transfer function, Validation of the longterm strain sensor characteristics, matching of specific measurement requirements with environmental conditions, and, moreover, the verification of Standards for use of strain sensors. T2 - IEEE Sensors 2011 conference CY - Limerick, Ireland DA - 28.10.2011 KW - Fibre optic sensors KW - Structural health monitoring KW - Validation KW - Strain sensor KW - Surface application reliability PY - 2011 SN - 978-1-4244-9288-6 U6 - https://doi.org/10.1109/ICSENS.2011.6127253 SP - 1337 EP - 1340 AN - OPUS4-24655 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schukar, Vivien A1 - Baitinger, Eugen A1 - Kusche, Nadine A1 - Mewis, Franziska T1 - Delamination-diagnosis-method for adhesively surface-applied FBG strain sensors T2 - 23rd International Conference on Optical Fibre Sensors CY - Santander, Spain DA - 2014-06-02 PY - 2014 AN - OPUS4-30768 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kusche, Nadine A1 - Schukar, Vivien A1 - Schilder, Constanze A1 - Köppe, Enrico A1 - Habel, Wolfgang ED - Chang, F.-K. T1 - Development and qualification of FBG-based strain patches and rosettes N2 - A fibre Bragg grating (FBG) strain patch specially adapted for long-term and high-strain applications was developed and characterised. Additionally, in the case of unknown main stress axis, two fibre optic strain rosettes were developed. The design concept for the patch and the rosettes is based on a glass fibre reinforced plastic (gfrp) carrier material. The patches were characterised due to their strain gauge factor and fatigue behaviour. As a result, FBG strain patches with linear strain behaviour and excellent fatigue resistance were developed and can be used as part of a monitoring system for aerospace structures or wind turbine power plants. The rosettes were designed to be small in geometrical size and their strain transfer behaviour was characterised. T2 - 8th International workshop on structural health monitoring 2011 CY - Stanford, CA, USA DA - 13.09.2011 KW - Fibre Bragg grating KW - Patch KW - Rosette KW - Strain gauge factor KW - Fatigue behaviour KW - Validation PY - 2011 SN - 978-1-60595-053-2 VL - 2 SP - 1457 EP - 1465 PB - DEStech Publications, Inc. AN - OPUS4-24512 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schilder, Constanze A1 - Kusche, Nadine A1 - Schukar, Vivien A1 - Habel, Wolfgang ED - Liao, Y. ED - Jin, W. ED - Sampson, D.D. ED - Yamauchi, R. ED - Chung, Y. ED - Nakamura, K. ED - Rao, Y. T1 - Experimental qualification and validation of fibre optic strain sensors N2 - Strain sensors used in practical applications must provide reliable measurement data. To achieve this, sensor systems must be validated by using experimental facilities that enable physically independent statements about the performance of the sensor components. The paper describes qualification and validation procedures using a special facility to qualify surface-applied strain sensors and to achieve reliable sensor results. Based on examples concerning fibre optic strain sensor patches with and without FBG sensors, the determination of the strain gauge factor also under combined thermal and mechanical loading will be presented. These results are the basis for development of guidelines and standards. T2 - OFS2012 - 22nd International conference on optical fiber sensors CY - Beijing, China DA - 2012-10-15 KW - Fiber Bragg gratings KW - Sensors PY - 2012 U6 - https://doi.org/10.1117/12.968801 SN - 0277-786X SN - 1996-756X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE IS - 8421 SP - 1 EP - 4(?) PB - SPIE, the International Society for Optical Engineering CY - Bellingham, Wash. AN - OPUS4-27321 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schilder, Constanze A1 - Kusche, Nadine A1 - Schukar, Vivien A1 - Münzenberger, Sven A1 - Habel, Wolfgang T1 - Experimental qualification by extensive evaluation of fibre optic strain sensors N2 - Fibre optic strain sensors used in practical applications have to provide reliable measurements. Therefore, the applied sensor and the sensor systems must be validated experimentally. This can be achieved with facilities which use physically independent measurement systems in order to avoid the influences caused by the application of a reference sensor. This paper describes the testing methods of the specially developed validation facility KALFOS for the qualification and evaluation of surface-applied strain sensors. For reliable sensor results, the performance of fibre optic strain patches with and without FBG under combined thermal and mechanical loading was investigated. Additionally, the strain gauge factor of the fibre optic strain patches with FBG was determined experimentally and compared to the specified strain gauge factor. These results will be the basis for the development of guidelines and standards concerning the application of the sensors. KW - Evaluation KW - Qualification KW - Strain transfer KW - Fibre optic sensors KW - Fibre Bragg grating KW - Patch KW - Strain gauge KW - Validation facility KW - Laser extensometer KW - Electronic speckle pattern interferometry PY - 2013 U6 - https://doi.org/10.1088/0957-0233/24/9/094005 SN - 0957-0233 SN - 1361-6501 VL - 24 IS - 9 SP - 094005-1 EP - 094005-7 PB - IOP Publ. Ltd. CY - Bristol AN - OPUS4-29424 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Schukar, Vivien A1 - Mewis, Franziska A1 - Kohlhoff, Harald ED - Yang, M. ED - Wang, D. ED - Rao, Y. T1 - Experimental validation of applied strain sensors - importance, methods and still unsolved challenges N2 - Fiber-optic strain sensors are increasingly used in very different technical fields. Sensors are provided with specifications defined by the manufacturer or ascertained by the interested user. If deformation sensors are to be used to evaluate the long-term behavior of safety-relevant structures or to monitor critical structure components, their performance and signal stability must be of high quality to enable reliable data recording. The measurement system must therefore be validated according to established technical rules and standards before its application and after. In some cases, not all details of the complex characteristic and performance of applied fiber-optic sensors are sufficiently understood, or can be validated because of a lack of knowledge and methods to check the sensors' behavior. This contribution focusses therefore on the importance of serious validation in avoiding a decrease or even deterioration of the sensors' function. Methods for validation of applied sensors are discussed and should reveal weaknesses in validation of embedded or integrated fiber-optic deformation and/or strain sensors. An outlook to some research work that has to be carried out to ensure a well-accepted practical use of fiber-optic sensors is given. T2 - 4th Asia Pacific optional sensors conference CY - Wuhan, China DA - 2013-10-15 KW - Fiber-optic sensor KW - Strain sensor KW - Reliability KW - Durability KW - Sensor characteristics KW - Application-related changes KW - Adhesive stability KW - Validation PY - 2013 U6 - https://doi.org/10.1117/12.2036591 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 8924 SP - 892410-1 - 892410-6 AN - OPUS4-29908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -