TY - JOUR A1 - Bartscher, M. A1 - Neukamm, M. A1 - Hilpert, U. A1 - Neuschaefer-Rube, U. A1 - Härtig, F. A1 - Kniel, K. A1 - Ehrig, Karsten A1 - Staude, Andreas A1 - Goebbels, Jürgen T1 - Achieving traceability of industrial computed tomography KW - Industrial computed tomography (CT) KW - Coordinate metrology KW - Traceability PY - 2010 DO - https://doi.org/10.4028/www.scientific.net/KEM.437.79 SN - 1013-9826 VL - 437 SP - 79 EP - 83 PB - Trans Tech Publ. CY - Aedermannsdorf AN - OPUS4-20985 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schulze, M. A1 - Staude, Andreas A1 - Neukamm, M. A1 - Neuschaefer-Rube, U. A1 - Goebbels, Jürgen A1 - Bartscher, M. A1 - Bellon, Carsten A1 - Hilpert, U. ED - Weckenmann, A. T1 - Hochgenaue Geometriebestimmung von Mikrobauteilen mit Computertomographie (CT) N2 - Ziel des Vorhabens ist die hochgenaue und vollständige Erfassung innerer und äußerer Geometrien von Mikrobauteilen mittels Mikro-Computertomographie (µCT). Industriell wichtige Mikrobauteile sind z.B. Einspritzsysteme, Festplattenkomponenten oder Instrumente für die minimal-invasive Chirurgie. Typische Bauteilgrößen liegen hier im Bereich 0,1 mm - 100mm; typische zu messende Strukturen haben Größen von 0,5 µm - 500 µm. Mit klassischen Methoden der Messtechnik ist eine schnelle und hochgenaue Erfassung der gesamten Oberfläche von Mikrobauteilen bisher kaum möglich. Innenstrukturen von Mikrobauteilen können mit keiner optischen oder taktilen Messtechnik zerstörungsfrei gemessen werden. Diese Einschränkungen sollen mittels hochgenauer µCT überwunden werden. Hierzu soll der Messprozess simuliert werden, um die Anwendung von Korrekturverfahren zur Genauigkeitssteigerung zu ermöglichen. CT-Messungen an kalibrierten Mikroprüfkörpern sollen die Korrekturverfahren verifizieren. Für die Kalibrierung der Prüfkörper sollen Multisensor-Verfahren entwickelt und getestet werden. Diese sollen es erlauben, Prüfkörper gleichzeitig hochgenau und mit großer Messpunktdichte zu kalibrieren. Es ist geplant, die an Prüfkörpern erreichten Messunsicherheiten und Auflösungen zum Projektabschluss an realen, industriellen Mikrobauteilen (z.B. Mikrozahnrädern) messtechnisch nachzuweisen. T2 - Abschlusskolloquium DFG Schwerpunktprogramm 1159 - Neue Strategien der Mess- und Prüftechnik für die Produktion von Mikrosystemen und Nanostrukturen CY - Erlangen, Deutschland DA - 06.10.2010 PY - 2011 SN - 978-3-8440-0358-1 SN - 0945-0769 SP - 36 EP - 52 PB - Shaker Verlag GmbH AN - OPUS4-24875 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ehrig, Karsten A1 - Bartscher, M. A1 - Goebbels, Jürgen A1 - Härtig, F. A1 - Kniel, K. A1 - Neukamm, M. A1 - Neuschaefer-Rube, U. A1 - Staude, Andreas ED - Denecke, M. ED - Walker, C. T1 - Dimensional control of micro components with synchrotron computed tomography T2 - 20th International congress on X-ray optics and microanalysis CY - Karlsruhe, Germany DA - 2009-09-14 KW - Synchrotron radiation KW - Computed tomography KW - Dimensional measurement KW - Micro components PY - 2010 SN - 978-0-7354-0764-0 SN - 0094-243X SP - 164 EP - 171 PB - American Institute of Physics AN - OPUS4-21293 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Staude, Andreas A1 - Bartscher, M. A1 - Ehrig, Karsten A1 - Goebbels, Jürgen A1 - Koch, M. A1 - Neuschaefer-Rube, U. A1 - Nötel, Jörg T1 - Quantification of the capability of micro-CT to detect defects in castings using a new test piece and a voxel-based comparison method N2 - We present a modified aluminium casting which is especially suited as test piece for measuring casting defects and the geometry by means of cone-beam micro-focus X-ray systems, and which may become a reference standard for dimensional measurements and defect detection. To obtain a test piece with inner geometries measured by tactile means, we divided a small aluminium cylinder head into four pieces in such a way that most inner surfaces can be reached with a tactile probe. Reference geometries (spheres and cylinders) were applied to define a coordinate system for aligning the measurements in the disassembled and re-assembled state. The four pieces were re-assembled after the tactile measurement. The test piece also contains casting defects. In order to be able to use the assembled cylinder head as reference sample for defect detection, measurements with higher spatial resolution and better signal-to-noise ratio were performed on the single parts. For improving the reliability of the reference measurements, CT measurements of each part were carried out in three different orientations, and the individual defect detections were combined to obtain a reference data set with a high probability of defect detection and a low rate of erroneous detections. A new method for comparing the defect detection in a CT measurement to a reference data set is demonstrated, which provides individual information on every detected flaw. We discuss the results of measurements in the assembled state with respect to the reference data for flaw detection. KW - X-ray tomography KW - Casting KW - Defects KW - Porosity PY - 2011 DO - https://doi.org/10.1016/j.ndteint.2011.05.006 SN - 0963-8695 VL - 44 IS - 6 SP - 531 EP - 536 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-24028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Neuschaefer-Rube, U. A1 - Becke, C. A1 - Sadowski, E. A1 - Tan, Ö. A1 - Staude, Andreas A1 - Zimmermann, J. ED - Weckenmann, A. T1 - Virtuelle Messgeräte und Simulationen im Mikrobereich - Potential und Grenzen T2 - Abschlusskolloquium DFG Schwerpunktprogramm 1159 - Neue Strategien der Mess- und Prüftechnik für die Produktion von Mikrosystemen und Nanostrukturen CY - Erlangen, Deutschland DA - 2010-10-06 PY - 2011 SN - 978-3-8440-0358-1 SN - 0945-0769 SP - 206 EP - 218 PB - Shaker Verlag GmbH AN - OPUS4-24877 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neuschaefer-Rube, U. A1 - Bartscher, M. A1 - Neugebauer, M. A1 - Härtig, F. A1 - Goebbels, Jürgen A1 - Ehrig, Karsten A1 - Staude, Andreas T1 - Measurement of micro gears - comparison of optical, tactile-optical and CT-measurements N2 - Micro gears are applied in an increasing quantity in many applications. Therefore, precise measurements are of growing importance to ensure their quality. This contribution describes the measurement of gears of a micro planetary gear set with a tactile probe, a tactile-optical probe, an optical sensor, and computed tomography (CT). For the tactile measurements, a high precision piezoresistive microprobe was used. A so-called fiber probe was applied for tactile-optical measurements. This probe applies image processing to determine the position of the tactile probing element. For all tactile and tactile-optical measurements, single point probing was used. The optical measurements were carried out with an imaging sensor based on focus variation. Due to limited accessibility, on some gears not all regions could be measured by the optical sensor and the tactile-optical probe. In contrast to this, with CT the whole part could be measured with high point density. We used a micro-CT system and carried out measurements with Synchrotron-CT. All the sensors used deliver measurement data in Cartesian coordinates. It is a challenge to transfer these data into coordinates in which gear parameters are defined. For this, special attention must be paid to the determination of the gear axis and to the orientation of the teeth. The applied procedures are detailed for different micro gears. The comparison between data of different measurements was carried out successfully. The deviations between the CT data and the tactile or tactile-optical data lie in the range of only a few micrometers. KW - Micro gears KW - Coordinate metrology KW - Computed tomography KW - Optical sensors KW - Tactile probes PY - 2011 DO - https://doi.org/10.1117/12.872413 SN - 0277-786X SN - 0038-7355 SN - 0361-0748 N1 - Serientitel: Proceedings series – Series title: Proceedings series IS - 7864 SP - 78640H-1 EP - 78640H-9 PB - VDE-Verl. CY - Berlin ; Offenbach AN - OPUS4-25998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neuschaefer-Rube, U. A1 - Bartscher, M. A1 - Schulze, M. A1 - Neukamm, M. A1 - Staude, Andreas A1 - Goebbels, Jürgen T1 - Messung von Mikrogeometrien mit industrieller Computertomographie N2 - Die industrielle Computertomographie (CT) ist ein gut bekanntes Verfahren zur zerstörungsfreien Prüfung von Werkstücken. In den letzten Jahren wird die CT aber zunehmend auch für dimensioneile Messungen von Werkstücken eingesetzt. Der wesentliche Vorteil der CT liegt in der Kompletterfassung mit hoher Messpunktdichte, die auch für andere Messverfahren unzugängliche, innere Geometrien einschließt. An kleinen Bauteilen können Strukturen bis herunter zu wenigen Mikrometern gemessen werden, wodurch sich das Verfahren gut für die Messung von Mikroteilen eignet. Nachteilig ist, dass viele Einflussgrößen das Messergebnis beeinflussen, was die Rückführung der Messergebnisse, die Bestimmung der Messunsicherheit und die Definition von Spezifikationen für CT-Anlagen erschwert. Der Beitrag stellt nach einer Einführung in das Verfahren Anwendungsbeispiele der CT an Mikroteilen vor. Darüber hinaus geht der Beitrag auf Prüfkörper und -verfahren zur Einmessung und Überprüfung von CT-Anlagen ein und berichtet über aktuelle Normungsaktivitäten. Abschließend werden Möglichkeiten zur weiteren Steigerung der Auflösung aufgezeigt, um zukünftig möglicherweise auch Nanogeometrien messen zu können. T2 - 4. Fachtagung Metrologie in der Mikro- und Nanotechnik 2011 - Messprinzipien - Messgeräte - Anwendungen CY - Erlangen, Germany DA - 25.10.2011 PY - 2011 SN - 978-3-18-092133-4 SN - 0083-5560 N1 - Serientitel: VDI-Berichte – Series title: VDI-Berichte VL - 2133 SP - 137 EP - 148 PB - VDI-Verl. CY - Düsseldorf AN - OPUS4-26251 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Binder, F. A1 - Bircher, B. A1 - Laquai, René A1 - Küng, A. A1 - Bellon, Carsten A1 - Meli, F. A1 - Deresch, A. A1 - Ulrich Neuschaefer-Rube, U. A1 - Hausotte, T. T1 - Methodologies for model parameterization of virtual CTs for measurement uncertainty estimation N2 - X-ray computed tomography (XCT) is a fast-growing technology for dimensional measurements in industrial applications. However, traceable and efficient methods to determine measurement uncertainties are not available. Guidelines like the VDI/VDE 2630 Part 2.1 suggest at least 20 repetitions of a specific measurement task, which is not feasible for industrial standards. Simulation-based approaches to determine task specific measurement uncertainties are promising, but require closely adjusted model parameters and an integration of error sources like geometrical deviations during a measurement. Unfortunately, the development of an automated process to parameterize and integrate geometrical deviations into XCT models is still an open issue. In this work, the whole processing chain of dimensional XCT measurements is taken into account with focus on the issues and requirements to determine suitable parameters of geometrical deviations. Starting off with baseline simulations of different XCT systems, two approaches are investigated to determine and integrate geometrical deviations of reference measurements. The first approach tries to iteratively estimate geometric deviation parameter values to match the characteristics of the missing error sources. The second approach estimates those values based on radiographs of a known calibrated reference object. In contrast to prior work both approaches only use a condensed set of parameters to map geometric deviations. In case of the iterative approach, some major issues regarding unhandled directional dependencies have been identified and discussed. Whereas the radiographic method resulted in task specific expanded measurements uncertainties below one micrometre even for bi-directional features, which is a step closer towards a true digital twin for uncertainty estimations in dimensional XCT. KW - Geometrical deviation KW - X-ray computed tomography KW - Uncertainty estimation KW - Virtual CT PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-553263 DO - https://doi.org/10.1088/1361-6501/ac7b6a VL - 33 IS - 10 SP - 1 EP - 15 PB - IOP Publishing CY - Bristol, UK AN - OPUS4-55326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neuschaefer-Rube, U. A1 - Illemann, J. A1 - Sturm, M. A1 - Bircher, B. A1 - Meli, F. A1 - Bellon, Carsten A1 - Evsevleev, Sergei T1 - Validation of a fast and traceable radiographic scale calibration of dimensional computed tomography N2 - A fast and highly precise method of determining the geometrical scale factor of computed tomography (CT) measurements has been validated successfully by Bundesanstalt für Materialforschung und -prüfung (BAM), the Federal Institute of Metrology (METAS) and Physikalisch-Technische Bundesanstalt (PTB) within the scope of AdvanCT (Advanced Computed Tomography for dimensional and surface measurements in industry), a project funded in the European Metrology Programme for Innovation and Research (EMPIR). The method has been developed by PTB and requires only two radiographic images of a calibrated thin 2D standard (hole grid standard) from two opposite directions. The mean grid distance is determined from both radiographs. From this and with the help of the calibration result, the radiographic scale and therefore the voxel size is determined. The procedure takes only a few minutes and avoids a time-consuming CT scan. To validate the method, the voxel sizes determined via this method were compared with voxel sizes determined from CT scans of calibrated objects. Relative deviations between the voxel sizes in the range of 10−5 were achieved with minimal effort using cone-beam CT systems at moderate magnifications. KW - Dimensional metrology KW - Voxel size KW - Industrial CT KW - Geometrical magnification PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-553271 DO - https://doi.org/10.1088/1361-6501/ac74a3 SN - 0957-0233 VL - 33 IS - 9 SP - 1 EP - 9 PB - IOP Publishing CY - Bristol, UK AN - OPUS4-55327 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartscher, M. A1 - Ehrig, Karsten A1 - Staude, Andreas A1 - Goebbels, Jürgen A1 - Neuschaefer-Rube, U. T1 - Application of an industrial CT reference standard for cast freeform shaped workpieces N2 - Industrial computed tomography (CT) today is an important method to analyze defects and to measure the geometry of technical products. The measurement capability of industrial CT often depends on the knowledge of the measurement errors being present. Only with this knowledge, effective corrections are possible by manufacturers, or adapted measurement procedures become possible for the customers. Thus, there is the strong need to have adequate reference standards both for the assessment of general dependencies and for the measurement of task-specific effects. Especially the latter are difficult to assess. This paper shows the application of a versatile dismountable workpiece-near reference body for the use with CT. The reference standard was made from a miniaturized cast aluminium (one-)cylinder head. It can be dismounted into four segments, each featuring reference geometries which enable a registration of CT measured and other reference datasets (e.g. from tactile CMM). The reference standard embodies complex freeform surfaces which are a challenging measurement task for CT and other sensors. Here the application of the reference standard is the study of the influence of material mixes. This is realized by adding pieces of other materials which disturb the mono-material measurement. Results of the application of the reference standard are presented using data from industrial micro-CT systems and CMM reference data. A special emphasis is given on the workflow of the data processing and the data analysis. T2 - International symposium on digital industrial radiology and computed tomography CY - Berlin, Germany DA - 20.06.2011 KW - Industrial reference standard KW - Computed tomographie KW - Freeform shaped workpieces PY - 2011 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-245532 SN - 978-3-940283-34-4 IS - DGZfP-BB 128 (We.4.3) SP - 1 EP - 12 PB - Deutsche Gesellschaft für zerstörungsfreie Prüfung e.V. (DGZfP) AN - OPUS4-24553 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -