Zeitraum:		08/2022 - 07/2025
Partner:		Institut für Technische Optik, Universität Stuttgart  PTB Working Group Asphere Metrology PTB Working Group Manufacturing Metrology
Förderung:		DFG

The accurate measurement of aspheres or freeform surfaces is challenging. The so-called "reference-free" form interferometry is a measurement technique where no physical reference surface exists. It is far more demanding than classical reference surface-based form measurement techniques as used, e.g., for flatness or sphere measurements. While it has many advantages, the absolute form accuracy reached by “reference-free” form interferometry is still limited. In this project the tilted-wave interferometer (TWI) is considered which is a promising “reference-free” technique for optical form measurement. The goal is to explore if and how additional absolute methods can be used to improve the accuracy of the absolute form measurements of such measurement systems. Virtual modeling of the experimental scenarios to be considered plays a crucial role  to find the optimal methods that are finally realized in the experimental setup and verified by means of special test objects.

Weitere Informationen: hier

MU Training - A MATHMET activity to improve quality, efficiency and dissemination of measurement uncertainty training

There is a documented need for a better understanding of measurement uncertainty and its evaluation in many communities. Recently this need was restated pointing to the importance of training on measurement uncertainty. MU Training is a MATHMET activity which will improve the quality, efficiency and dissemination of measurement uncertainty training. Based on a broad consortium, the project will

1. develop new material for measurement uncertainty training and
2. establish an active community for those involved in measurement uncertainty training.

More specifically, the new material (1.) will include an overview of existing courses, software and examples to guide trainees, as well as short videos explaining the need for, and a common difficulty in, evaluating measurement uncertainty. This material will be freely available on MATHMET’s website and will be actively disseminated to a large set of practitioners in metrology, academia and industry. The community (2.) will strengthen the capabilities of those teaching measurement uncertainty by opening courses and material within the consortium, as well as laying foundations for the development of new courses. A broader range and larger number of metrologists, researchers, university students and industrial audiences will receive good practice in training on measurement uncertainty during and well after the MATHMET activity. The MU Training activity is unfunded, and its results and impact will reflect on MATHMET and advance its network.

By creating new material for measurement uncertainty training at the beginners and at advanced levels, and by establishing an active community for those teaching measurement uncertainty at metrology institutes, universities, in accreditation and legal metrology, the activity will increase the understanding of measurement uncertainty and thus contribute to more reliable measurements from the highest scientific level down to the shop floor.

Zeitraum:		01/2020 - 12/2022
Förderung:		Deutsche Forschungsgemeinschaft (DFG)
Partner:		FU Berlin (Prof. Dr. Eckart Rühl)
		PTB Working Group IR Spectrometry (PTB 7.11, Dr. Bernd Kästner)

Functional nanomaterials provide the basis for novel forms of electronics, sensing or therapeutics. Their understanding and design require fabrication informed by nanoscale chemical mapping. Novel scanning probe-based spectroscopy using broadband infrared radiation emerged as a promising imaging technique at nanometer spatial resolution. However, the pixel-by-pixel data acquisition and conventional Fourier-transform schemes lead to prohibitive imaging times and enhanced radiation damage. This project aims to overcome these limitations by developing a novel hyperspectral imaging scheme based on Bayesian compressed sensing that utilizes prior knowledge about the spectra.

Weitere Informationen: hier

Zeitraum:		06/2019 - 11/2022
Förderung:		European Metrology Programme for Innovation and Research (EMPIR)
Partner:		6 Nationale Metrologieinstitute und Forschungseinrichtungen
		5 Wissenschaftlich-technische Institute

The aim of this project is to evaluate emerging and complementary Electric Properties Tomography (EPT) and Magnetic Resonance Fingerprinting (MRF) MR techniques, to develop quantitative Magnetic Resonance Imaging (MRI) analysis for more accurate disease diagnostics. Algorithms for analyzing EPT and MRF output signals will be developed and improved, with performance validated using fully characterized, SI-traceable, ‘phantom’ reference artefacts and monitored components. Diagnosis of high impact clinical conditions with these new techniques (such as cerebrovascular diseases) will be assessed, and results disseminated to end-users such as MRI manufacturers and the medical community.

Weitere Informationen: hier

Zeitraum:		06/2017 - 05/2020
Förderung:		European Metrology Programme for Innovation and Research (EMPIR)
Partner:		4 Europäische Nationale Metrologieinstitute und Forschungseinrichtungen
		3 Universitäten
		11 Industriepartner

The aim of the EMPIR project „Multiphase flow reference metrology“ is to explain and reduce the uncertainty in multiphase flow metering in the oil and gas industries. Therefore, a typical multiphase flow measurement set-up consisting of a 16 meter long horizontal pipe followed by a relatively complex measurement unit is examined experimentally and numerically. Within the working group 8.41, a variety of industrially relevant configurations with different oil, water, and gas flow rates are simulated with the commercial CFD code ANSYS Fluent. Depending on the prescribed superficial velocities of the gas and liquid phases, different flow patterns are observed at the end of the inflow section, which have an influence on the accuracy of the Venturi meter. The CFD simulations allow a visualization of the different structures in all parts of the geometry, even in areas that are hardly observable in experiments. Furthermore, the influence of different parameters (like the use of different fluids in the laboratories taking part in the experimental intercomparison of the project) on the pressure measurement in the Venturi tube has been investigated. An advantage of the simulation over the experiment is that it is possible to change only one parameter and keep the others constant. Thus, the influence of the different parameters can be investigated separately.

Im Rahmen einer wissenschaftlichen Kooperation werden statistische Nachweisverfahren für ein Qualifikationsverfahren im gesetzlichen Messwesen untersucht. Um Verbrauchsmessgeräte für das effiziente Stichprobenverfahren gemäß § 35 der Mess- und Eichverordnung (siehe Abschnitt 4.3 in der GM-VA SPV) qualifizieren zu können, werden statistische Hypothesentests zum Nachweis von Verletzungen der Normalverteilung und von Überschreitungen einer geringen Ausfallrate ausgewählt und angepasst, sowie Stichprobenumfänge hierfür empfohlen.

Weitere Informationen: Stichprobenverfahren im gesetzlichen Messwesen

Zeitraum:		07/2018 - 06/2021
Förderung:		European Metrology Programme for Innovation and Research (EMPIR)
Partner:		12 Nationale Metrologieinstitute und Designierte Institute
		2 Industriepartner und wissenschaftlich-technische Institute
		2 Europäische Akkreditierungsbehörde
		1 Regulierungsbehörde

Dieses Projekt erstellt einen umfassenden Satz an ausgearbeiteten Beispielen, die illustrieren wie die Prinzipien der Messunsicherheitsbestimmung normative und andere Praxis unterstützen können.

Es hat zum Ziel, die harmonisierte Bestimmung der Messunsicherheit nach international anerkannten Standards und Richtlinien in vielen Fachrichtungen des Messens  zu fördern.

Um dieses Ziel zu erreichen, wird das Projekt neue und verbesserte, anpassbare Beispiele und Vorlagen zur Unsicherheitsbestimmung an das Joint Committee for Guides in Metrology (JCGM) als Herausgeber der international anerkannten Richtlinie Guide to the expression of uncertainty in measurement überreichen. Darüber hinaus wird das Projekt Beispiele für etwa 10 Normungsgremien bereitstellen, die besonderen Bezug zu den dort zu entwickelnden Normen haben. EUROLAB wird Projektergebnisse an nationale Verbände weitergeben, die ungefähr 2000 Laboratorien und Konformitätsbewertungsstellen erreichen und Tätigkeiten wie Prüfung, Überprüfung und Zertifizierung durchführen sowie insgesamt 100000 Mitglieder haben. Dadurch wird das Projekt gute Praxis in der Unsicherheitsbestimmung stark verbreiten und dies an einen extrem weiten Kreis an Endnutzern.

Weitere Informationen: hier

Europe, and the world, will be dependent for many decades to come on the production of oil and gas for its underpinning energy needs. Multiphase flow measurement is a fundamental enabling metrology in subsea oil and gas production. However, field measurements exhibit high measurement uncertainty, costing industry billions of euros in financial exposure and production inefficiencies. To improve this situation requires a reference measurement capability that is consistent and comparable across different test laboratories that offer this service. This project will address this need by establishing harmonisation of measurements between multiphase flow reference laboratories.

Zeitraum:		09/2017 - 08/2020
Förderung:		Bundesministerium für Wirtschaft und Technologie (BMWi)
Partner:		JCMwave GmbH

Ziel des Verbundprojekts  ist die Entwicklung einer Software-Toolbox, die Unsicherheiten auch für komplexe Modelle des Messprozesses in der Optik schnell und nutzerfreundlich bestimmen kann (Uncertainty Quantification). Dabei soll mit Hilfe spezieller numerischer Methoden der Einfluss von Messunsicherheiten als  Eingangsparameter auf die Ergebnisse einer Simulation oder eines inversen Verfahrens effizient quantifiziert werden. Die so entwickelte Toolbox kann für die Optimierung von Bauteilen und die schnelle Auswertung indirekter Messungen verwendet werden. 

Weitere Informationen: hier

Im Rahmen der Elektromobilität ist die schnelle Bestimmung des Gesundheitszustands der Batterien von hoher Bedeutung, insbesondere zur genauen Angabe der verbleibenden Reichweite einer Akkuladung. In einer Kooperation mit einem Industriepartner wird in den beiden Fachbereichen „Physikalische Chemie“ und „Mathematische Modellierung und Datenanalyse“ gemeinsam eine statistische Methode zur Bestimmung des Gesundheitszustands weiterentwickelt und erprobt.

Weitere Informationen: hier

Zeitraum:		07/2016 - 06/2019
Förderung:		European Metrology Programme for Innovation and Research (EMPIR)
Partner:		10 European national Metrology Institutes and Research Institutes
		1 Industrial partners  ("Collaborators")

The aim of this project is to address metrology needs for the health sector by developing a physical standard for quantitative medical imaging applicable to a range of imaging techniques (modalities) and new data analysis techniques for patient care. This will support the reliability and traceability of clinical data and ensures the comparability of diagnostic and treatment information in clinical trials. In addition, the project will investigate metrological approaches for radiation protection to support the health protection of citizens.

Weitere Informationen: hier

Zeitraum:		06/2016 - 05/2019
Förderung:		European Metrology Programme for Innovation and Research (EMPIR)
Partner:		11 European national Metrology Institutes and Research Institutes
		4 Industrial partners  ("Collaborators")

Aspheres and freeform surfaces are components used in a variety of optical systems, from medical imaging to astronomy. They deliver better image quality compared to traditional spherical elements and as a result their use is growing rapidly. However, the ability to develop higher-performance aspheres and freeform surfaces is limited by the precision with which the shape of their surface can be measured. Although modern optical polishing techniques can remove material at the nanometre level, measurement techniques are unable to measure with the same degree of precision. This project will build on the work of the previous EMRP project IND10 Form, which achieved measurements below 100 nanometres, by developing new measurement capabilities within European National Measurement Institutes to routinely measure below 30 nanometres. The capabilities developed will strengthen Europe’s position in global optics, and will be used by industry to develop a new level in optical device performance.

Weitere Informationen: hier

Zeitraum:		07/2015 - 06/2018
Förderung:		European Metrology Programme for Innovation and Research (EMPIR)
Partner:		National Physical Laboratory (NPL), Teddington, UK
		HBM GmbH (Germany)
		Rolls Royce plc (UK)

The aim of this project is to maximise uptake by industry end users and the Joint Committee for Guides in Metrology (JCGM) of outputs of EMRP JRP IND09 (Traceable dynamic measurement of mechanical quantities) by providing concrete, specific and directed advice on how to make best use of the results of dynamic calibrations provided by NMIs. 

More information can be found on the project website:

http://mathmet.org/projects/14SIP08

and the software repository home page:

https://github.com/eichstaedtPTB/PyDynamic

In  diesem  Projekt  soll  unter  Ausnutzung  von  in  der  PTB  vorhandenem  Wissen  und Algorithmen gemeinsam mit der Firma Chromasens GmbH ein Verfahren entwickelt werden, welches  basierend  auf  einer  mathematischen  Modellierung  der  Einflussgrößen  eine  robuste und  verlässliche  Rekonstruktion  ortsaufgelöster  Farbspektren  aus  spektral  zerlegten Messungen  liefert.  Ziel  ist  es,  ein    validiertes  Verfahren  zu  entwickeln,  welches  einen routinemäßigen  Einsatz  von  multispektralen  Zeilenkameras  in  industriellen  Anwendungen erlaubt.

Weitere Informationen: hier

Multiscale pattern formation refers either to the simultaneous appearance of competing unstable modes with different critical wavelengths or to the interaction of pattern formation with spatial heterogeneities. This project will focus on control strategies in order to obtain desired or suppress unwanted patterns in multiscale reaction-diffusion systems. We plan (i) to study simple generic models to develop appropriate control methods like time delay and nonlocal coupling and (ii) to consider control of patterns on biomembranes as well as during pathological cardiac dynamics as applications for multiscale systems.

Weitere Informationen: hier

Stromnetze im Mittel- und Niederspannungsbereich sind zunehmend einer bidirektionalen Lastenverteilung ausgesetzt. Dies erfordert auch auf dieser Ebene eine verlässliche Prognose, Überwachung und Schätzung des Netzzustandes. Da jedoch nur auf der Hochspannungsebene eine vollständige Messinfrastruktur vorhanden ist, erfordert die Bestimmung des Netzzustandes verlässliche mathematische Verfahren für unvollständig bekannte Zustandsraummodelle. Die PTB Arbeitsgruppe 8.42 entwickelt und untersucht daher zusammen mit 16europäischen Partnern geeignete mathematische und statistische Verfahren.

Weitere Informationen: hier

Typical multiphase measurement systems can have an uncertainty on component flow rate of 20% or greater under field conditions. The overall aim of the project is to help establish the infrastructure whereby multiphase flowmeters can be more reliably evaluated and/or verified for their application(s) – thereby enabling developers to advance state-of-the-art in flow measurement.To develop an accurate and validated metrological reference network, using test and calibration facilities for multiphase flow.

Weitere Informationen: hier

The multicellular aggregation of microorganisms like bacteria and amoebae is largely controlled by the interplay of physical properties like cell shapte and motility with intracellular processes and the exchange of biochemical signals between the cells. The aim of the project is to develop realistic models for aggregation and pattern formation in myxobacteria at the microscopic (= agent-based models with Langevin dynamics) and macroscopic level (continuum equations for cell densities of reaction-diffusion-advection type). The models shall address basic physical properties (self-propulsion, volume exclusion and nematic alignment) and biochemically regulated internal clocks and the resulting reversal rates of individual cells.

RDAM systems include active fluids where mechanical stress involves an active component that is controlled by one or more chemical regulator species which obey reaction-diffusion-advection equations. The project builds on previous work describing pattern formation in non-moving circular droplets with fixed boundaries. The existing model shall be extended to allow for motion of the droplet. This will be achieved by considering the cytoplasm as a viscoelastic fluid and by introducing moving boundary conditions. Phase-field methods will be applied as effective computational alternative to a model with a sharp interface.  The model aims at the description of the dynamics of moving protoplasmic droplets of Physarum polycephalum and shall be compared to experimental observations in this system.

The proposed JRP will provide validated and reliable optical measurements and methods with traceability to the SI-system wherever it is practicable to do so for the range of multidimensional reflection measurements. The general objective is to meet the demands from industry to describe the overall macroscopic appearances of modern surfaces by developing and improving methods for their measurement which rightly correlates with the visual sensation. In specific, the project deals with the Goniochromatism, Gloss and Fluorescence properties of dedicated artefacts, which will be investigated in the three main vertical workpackages. The horizontal workpackages address these subjects to the Modelling and Data Analysis and the Human Visual Perception, in order to give an irreducible set of calibration schemes and handling methods.

Weitere Informationen: hier

In der industriellen optischen Messtechnik werden zunehmend Messverfahren eingesetzt, die eine vollständige Charakterisierung des Messobjektes in Form von differentiellen Messungen liefern. Beispiele hierfür sind kamerabasierte Messungen von räumlichen Temperatur- oder Leuchtdichteverteilungen. Aus den differentiellen Messungen können integrale Größen berechnet werden, die die benötigte Rückführung auf SI Basiseinheiten ermöglichen. Dies erfordert eine Charakterisierung der Genauigkeit der berechneten integralen Größen. Aufgrund der sehr hohen Dimensionalität der differentiellen Messungen sowie deren Korrelation ist dies derzeit in der Industrie allerdings nicht durchführbar. Ziel des Projektes ist es, geeignete Verfahren zu entwickeln, die eine routinemäßige Charakterisierung der integralen Größen ermöglichen.

The project develops novel approaches to measurement uncertainty evaluation and enable their consistent application, illustrated by appropriate case studies. The dissemination of these methods is ensured by providing input for future revisions of the Guide to the Expression of Uncertainty in Measurement (GUM), its supplements and other relevant documents and by providing algorithms and software. It focuses on three areas where new uncertainty analysis methods are needed: inverse and regression problems, computationally expensive model functions, conformity assessment and reliable decision-making.

In addition, the project emphasizes application of these methods to challenging areas where a strong need for new uncertainty evaluation methods has been identified. These include new analytical technologies for biochemistry and biotechnology (enzyme-linked immunosorbent assays - ELISA, polymerase chain reaction - PCR), transport processes (fluid flow, thermophysical properties of materials), industry and regulation (scatterometry, fire safety engineering, conformance testing for healthcare products).

Weitere Informationen: hier

Dimensional metrology of small structures is a basic subject important for applications within a wide variety of areas mainly in the semiconductor and optical industries but also in mechanical engineering (e.g. length and angle encoders) as well as in biological and medical industries. Dimensional metrology of high-end laterally structured functional surfaces is a constant challenge due to the progressive minimisation of structures combined with an increasing impact of feature details on the functionality of these surfaces. The development of sophisticated dimensional metrology of structures in the sub micrometer-range is therefore an important condition for the further development of technologies for optics and semiconductor industries.

Scatterometry is a promising measurement technique for dimensional metrology since it is fast, non-destructive and has basically no “resolution limit”. However, so far scatterometry is not capable of performing absolute form measurement. The goal of this project is to overcome this limitation by improving according measurement and data analysis methods. The investigations and results of this project will enable the design, development, characterisation and calibration of a scatterometry reference standard to face the tough specifications demanded nowadays.

Weitere Informationen: hier

The aim of this project is to establish traceability for the three mechanical quantities force, torque and pressure for measurements under dynamic conditions. The required research carried out in this JRP will provide the foundation for a European infrastructure for traceable dynamic measurements of these mechanical quantities.

The JRP-Partners will establish a metrology infrastructure for traceable dynamic measurements of force, pressure and torque, set up and validate primary calibration methods, develop methods for consistent and reliable evaluation of measurement uncertainty, and provide dynamic traceability of the electrical components of the measurement chain.

Weitere Informationen: hier

This project addresses the urgent need of the European optics and precision engineering industry and of basic research institutes for a significant improvement of accuracy and spatial resolution of the “absolute” surface form measurement of flats, aspheres and free-form surfaces. Absolute, in this context, refers to the measurement of optical surfaces delivering the full 3D form. Absolute form data are required, e.g. ,for the manufacturing of high-end asphere optics, strongly curved freeform surfaces used for special optics, for the calibration of measuring systems used in industry for in-production metrology, and for synchrotron and astronomical systems.

Weitere Informationen: hier