Metrological Practice Research Articles

Calibration complex of radio measuring equipment

Modern trends in the development of radio measuring equipment require improvement of the principles of metrological support of these devices and corresponding reference base. The new approach is based on the digitalisation of equipment, programming of measurement procedures, and the transition from single measurement standards to measurement complexes. The paper describes the complex developed at the NSC “Institute of Metrology” and designed for verification and calibration of a wide range of radio measuring equipment, where all these approaches are realised, presents methodological, software and hardware features of its construction, as well as the advantages and possibilities of this approach in metrological practice. On the example of the method of “Bessel Function Zeros”, which was somewhat forgotten due to the cumbersome nature of its implementation by analogue methods and equipment, it is shown that with the new approach this method gets a “second birth”, moreover, at a higher metrological level. It is shown that the use of direct digital synthesis oscillators can significantly improve the “electronic counting frequency meter” method, in particular, prevent the phenomenon of “frequency capture”, which limited the capabilities of the method and introduced additional measurement uncertainty. Moreover, the additional properties of the complex associated with the use of the R&S FSL spectrum analyser with the K7 analogue signal demodulator option are explained in more detail. A list of other methods realised in the complex is given, among which the “combination frequencies” method, deserves a special attention, providing the highest resolution in measuring nonlinear distortions of both quasi-harmonic and modulated signals. It is shown that the complex is a flexible apparatus, the work programme of which can be adjusted and supplemented. Information on the structure of the complex, hardware solution of a number of nodes, programming language, etc. is given.

Experimental installation of a reference source of low currents for calibration of electrometers

Today, there is great scientific interest in the possibility of implementing reference sources of low currents based on single-electron pumps using the single-electron tunneling effect and the modern definition of the SI system. However, the practical use of this effect in everyday metrological practice has not yet reached the stage of widespread use. Typically, for routine calibration work in laboratories, either mass-produced instruments (low current sources and meters, electrometers) are used, which are calibrated against higher standards, or specially designed precision current sources. The article describes a reference installation developed on the basis of the VNIIFTRI, where in the mode of generating ultralow currents the principle of forming a linearly increasing voltage on a reference capacitor is used. A simplified block diagram of the reference setup is shown. Issues of practical adjustment of modern electrometers are considered. The generalized results of participation in international comparisons on low currents EURAMET.EM-S44 “Comparison of ultra-low DC current sources” conducted by national metrological institutes in 2018–2020 are presented. The results of a metrological study of the calibration factor Q and an example of calculating the uncertainty budget of measurements carried out at the VNIIFTRI as part of these international comparisons are presented. The research described in the article to increase the accuracy of measurements of small and ultra-low currents of this level has valuable practical significance in the field of electrical measurements, in aeroionometry and metrology of ionizing radiation.

THE ROLE OF PRECISION METROLOGY IN ENHANCING MANUFACTURING QUALITY: A COMPREHENSIVE REVIEW

Precision metrology plays a pivotal role in modern manufacturing processes by ensuring the attainment of high-quality standards and the optimization of production efficiency. This comprehensive review delves into the significance of precision metrology in enhancing manufacturing quality across diverse industries. The review encompasses an examination of advanced metrological techniques, their applications, challenges, and future prospects. The review begins by elucidating the fundamental principles of precision metrology, emphasizing its critical role in quantifying dimensional accuracy, surface finish, and other crucial parameters in manufacturing. It explores the evolution of metrology from conventional methods to state-of-the-art technologies such as coordinate measuring machines (CMMs), optical metrology, and 3D scanning systems. The integration of these techniques into modern manufacturing environments has revolutionized quality control processes, enabling real-time monitoring and rapid feedback mechanisms. Furthermore, the review highlights the multifaceted applications of precision metrology across various industries, including automotive, aerospace, electronics, and medical devices. It elucidates how metrological advancements have facilitated the production of intricate components with tight tolerances, thereby enhancing product performance, reliability, and safety. Additionally, the review examines the role of metrology in ensuring compliance with regulatory standards and certifications, crucial for industries with stringent quality requirements. Despite its numerous benefits, precision metrology also poses challenges, such as measurement uncertainties, calibration complexities, and data interpretation issues. The review discusses these challenges in detail and explores emerging strategies and technologies aimed at mitigating them. Furthermore, it addresses the need for standardized metrological practices and international collaboration to foster interoperability and harmonization in global manufacturing ecosystems. Looking ahead, the review outlines future directions and opportunities in precision metrology, including advancements in artificial intelligence, machine learning, and Internet of Things (IoT) integration for predictive maintenance and autonomous quality control systems. It underscores the importance of continued research and innovation in metrology to address evolving manufacturing demands and ensure sustained improvements in product quality and competitiveness. In conclusion, this comprehensive review underscores the indispensable role of precision metrology in enhancing manufacturing quality, driving innovation, and shaping the future of modern industry.
 Keywords: Precision, Metrology, Manufacturing, Quality, Review.

An efficient algorithm for areal morphological filter

This article discusses morphological filtering for assessing a areal parameters of a texture of engineering products. A data organization structure has been proposed that makes it possible to increase the efficiency of an iterative algorithm for enumerating a surface coordinates. Morphological filters complement the standard Gaussian filter to evaluate the functional properties of a surface. The widespread use of the areal morphological filtering in metrological practice is currently hampered by the lack of an effective algorithm. An algorithm based on a matrix representation of morphological operations on the surface coordinates is presented. For this purpose, different indexing of points on a primary surface and a structuring element has been introduced. A sphere or flat segment is used as the structuring element. The high performance of the developed algorithm is ensured due to the fact that all calculations are carried out by enumerating the surface coordinates in one pass, without nested loops, as in some other algorithms. Algorithms for morphological operations of dilation and erosion are presented, on the basis of which a closing and opening filters are constructed. Simulations carried out for various data sets and comparison with known morphological filtering algorithms confirmed the high efficiency of the designed algorithm. The results obtained can be used to analyze the functional properties of product surfaces.

Freeform digital twin approach to develop the HP 300 freeform verification standard

Inspired by previous experience in freeform metrology practice and industrial needs, the Czech Metrology Institute developed the freeform standard Hyperbolic paraboloid 300 of dimensions 300mm×300mm×160mm with a freeform functional area of approximately 64000mm2. The paper presents a mathematical–metrological approach to finding a suitable strategy for calibrating the freeform standard on a coordinate measuring machine with a tactile probing system. The calibration strategy consists in the development of a freeform digital twin of the standard, i.e. a continuous digital representation of a freeform measured value with associated uncertainty. A procedure to estimate the uncertainty of the coordinate freeform measurement is described, too. After calibration, the Hyperbolic paraboloid 300 standard will become a verification gauge suitable for use as a precision reference in advanced freeform metrology similar to common verification gauges widely used in length metrology.

Resistors C5-60 in metrological practice: experience of use

Resistors C5-60 in metrological practice: experience of use

The weight of Wittgenstein's standard metre

AbstractParagraph 50 of Wittgenstein's Philosophical Investigations famously says that there is one thing of which one can neither state that it is 1 m long nor that it isn't: the standard metre in Paris. Consensus appears to be that (1) exegetically speaking, Wittgenstein affirms this claim, and (2) systematically, whether or not one agrees with it, the practice of using a material artefact as a measurement standard has important philosophical consequences. In this paper, in contrast, we show that (1') Wittgenstein does not affirm the standard metre claim and (2') historical facts about material length standards do not warrant deeper philosophical conclusions. References to material measurement standards in the literature gravely distort the actual metrological practices of developing and using such standards.

The Behaviour of Consumer and Strategy of Development of Legal Metrology Performance

This study explores the knowledge, attitude, and practice (KAP) in legal metrology since there is very little information on knowledge, attitude, and practice concerning legal metrology. The survey data gathered from 24.360 respondents across 34 provinces in Indonesia assessed the understanding concerning legal metrology by applying descriptive statistics, correlation, and multinomial regression analysis. The results show the consumers generally have better knowledge in legal metrology, an excellent attitude about the importance of legal metrology, and critical behaviour in mitigating fraudulence risk when doing trade transactions at the marketplace. Variable of gender and age tends to impact knowledge, attitude, and practice concerning legal metrology issues. The study also found that the relationship between knowledge, attitude, and practice is likely to be non-linear. The outcomes of exploring the behaviour of consumers through knowledge, attitude, and practice in legal metrology can be beneficial for legal metrology authorities to analyze the impact of setting policies and programs. Also, to develop a strategy to increase public awareness in legal metrology so that the consumers can be more critical in protecting themselves from various fraudulence in measurement in trade transactions.

The Spatial Pattern of Fraudulence Risk in Legal Metrology and Its Socio-Economic Drivers

This study develops a fraudulence risk in the legal metrology model, gaining insight into urban spatial characteristics as contextual variables that may cause a risk of fraud. The model uses Geographically Weighted Regression on the Metrological Consumer Index data of Bandung, West Java, Indonesia. The findings indicate a wide distribution of recorded fraudulence risk in legal metrology across Bandung, with a spatially clustered pattern based on spatial and context of varying neighbourhood attributes. The results also show an increase in the fraudulence risk in legal metrology in the central business district of Bandung. Such phenomena could be attributed to the residents who trade and are involved in the measurement practice. The findings also suggested that the areas with more senior residents were more likely to have a high fraudulence risk in legal metrology. On the other hand, areas with a high proportion of poor and lesser-educated people exhibit low risk.These findings are helpful for legal metrology authorities seeking to establish appropriate strategies to mitigate adverse impacts of fraudulence risk in legal metrology practice on communities. It can also help identify high fraudulence risk in legal metrology areas to geo-target when and where to disseminate information to increase awareness of the dangers.

Separation Theorems in Econometrics and Psychometrics: Rasch, Frisch, Two Fishers and Implications for Measurement

In 1959, Ragnar Frisch prompted Georg Rasch to formalise a separability theorem that continues today to serve as the basis of a wide range of theoretical and applied developments in psychological and social measurement. Previously unnoted are the influences on Rasch exerted by Frisch’s concerns for data autonomy, model identification and necessary and sufficient conditions. Although Rasch acknowledged Frisch’s prompting towards a separability theorem, he did not acknowledge any substantive, intellectual debt to him, nor to Irving Fisher, but only to Ronald Fisher. Rasch appears to have developed a special interest in sufficiency and identified models when studying with Frisch in 1935, and in 1947, when Rasch accompanied Tjalling Koopmans to the University of Chicago and the Cowles Commission for Research in Economics. I. Fisher’s separation theorem continues to be relevant in econometrics, and interest in Rasch’s separability theorem is growing as the measurement models based on it are adopted in metrological theory and practice. The extensive interrelations between measurement science, metrological standards and economics suggest paths towards lower transaction costs and more efficient markets for individualised exchanges of human, social and natural capital. Equally, if not more, surprising are the implications for a poetic art of complex, harmonised relationships played out via creative improvisations expressed using instruments tuned to shared scales. JEL: B41, C10, C13, C20, C42, D70, E60, H54, I11, I21, I31, P11

Development of reference materials for gas permeability

The article presents the development of reference materials of gas permeability of rocks (imitators) with traceability to Get 210–2019: State Primary Standard of Units of Specific Adsorption of Gases, Specific Surface Area of Pores, Specific Volume of Pores, Dimension of Pores, Open Porosity, and Coefficient of Gas Permeability of Solid Substances and Fabricated Materials. At the time of the beginning of this study, in the system of metrological assurance of gas permeability coefficient measurements, there were only reference materials of an approved type with traceability to the measurement results obtained in an interlaboratory experiment using gas permeability analyzers that were calibrated using the same reference materials, and reference materials with traceability to the State Primary Standard were absent. As a result, in the metrological practice of gas permeability measurement, there was no stable basis for comparison. This fact prompted the authors to research work in this area. The article considers the key stages of the process of reference materials development: analysis of similar reference materials of an approved type, selection of the starting material for reference materials, performing experimental research, and determining, on the basis of this research, the metrological characteristics of reference materials. Ceramic cylinders based on aluminum oxide were used as the starting material for reference materials; the method to measure the gas permeability coefficient is based on the method of stationary filtration. Measurements of the gas permeability coefficient were carried out on samples with different gas permeability using nitrogen and helium gases. Based on the results of these measurements, for each sample, the gas permeability coefficients were calculated at the given reverse pore pressure and the absolute gas permeability coefficient. As a result of the study, a set of reference materials of gas permeability of rocks (imitators) GSO 11546–2020 / GSO 11550–2020 was approved, the range of certified values is (0.1 10 –3 – 5) μ m 2 , and the expanded uncertainty of certified values Uo (k = 2, P = 0.95), is 3 %. The authors believe that the GSO 11546–2020 / GSO 11550–2020 dataset will ensure metrological traceability and reliability of gas permeability coefficient measurements. As a result, it will bring practical relevance to a petrophysical research laboratory.

Creation of a New European Metrology Network on Pollution Monitoring (POLMO)

Driven by a wide set of European regulations, strategies and action plans, to cope with and to minimize environmental pollution in Europe, the need for pollution monitoring especially on chemicals and radionuclides is constantly growing in importance as it supports the ambition of the European Union: “In 2050, we live well within the planet’s ecological limits”. This can be reached only on the basis of high-quality data on pollution monitoring as well as strong metrological cooperation between all relevant European partners and stakeholders. To foster this goal a strong, collaborative, multi-disciplinary, long-term and self-sustaining “European Metrology Network on pollution monitoring”, as a metrological reference infrastructure, needs to be generated and managed. Such a metrological network will be developed over the next years within the framework of an EMPIR network project called POLMO. POLMO will focus first on chemicals and radionuclides pollution in the different compartments of the environment (water, air, soil) but also will strive to expand its expertise to other areas such as light or noise pollution on longer terms. The detailed objectives of the POLMO network are: To become an international point of focus and create stronger connections for all the different stakeholder communities (active networks and associations, research centres, testing laboratories, manufacturers, industry, standardization bodies, regulators) with NMIs/DIs. This should allow new approaches to meet stakeholder requirements by developing multidisciplinary metrological research overpassing current regulatory principles. To maximize efficiency of NMIs/DIs activity and minimise resources (human, infrastructures, financial) as well as knowledge, data and best-practice transfers between NMIs/DIs and with the main EU organisations as well as stakeholders in the POLMO context. Demonstrate the role of metrology in the European research area. Moreover, to define the place and role of the metrology in the pollution monitoring chain of measurements and to demonstrate its added value and benefit. To maximize and accelerate dissemination of reliable metrology practices for pollution monitoring through mutually recognized and agreed approaches The goal of this poster is to describe how the POLMO Metrology Network will be implemented from mid 2022 in particular by the means of an EMPIR JNP (Joint Network Programme) in the framework of EURAMET (European Association of National Metrology Institutes). The project could support the need for harmonization and reliability of e-DNA measurements, as necessary to support their recognition, by organizing the development of missing metrological tools at European level

Assessing laser powder bed fusion system geometric errors through artifact-based methods

Additive manufacturing (AM) machines have developed more rapidly than standardized frameworks needed for the qualification of their geometric capabilities. While some manufacturer-specific methods exist to test capabilities and perform some calibration tasks, standardization efforts have only recently been undertaken in the form of ISO/ASTM 52902. In this study, the recommended methodology prescribed by the standard was implemented by building geometric artifacts with a laser powder bed fusion (LPBF) system and performing dimensional inspection with a coordinate measurement machine (CMM), amongst other methods. Typical dimensional capabilities of the LPBF system are identified and commentary is made on applying metrology methods, detecting geometric error, and diagnosing base causes in the LPBF system. In doing so, favored metrology practices and measurement analysis methods auxiliary to the standard are proposed. Artifact measurements were used to characterize beam positioning error and beam offset error. Methods for decoupling the effects of error sources are proposed. Difficulties in the inspection of AM components are identified, and the effects of various CMM measurement strategies are evaluated. Insights on the application of the new standard are presented, along with commentary as to its fitness for the LPBF process.

Desarrollo de Instrumentos Virtuales en Excel como Apoyo a la Enseñanza de la Metrología

La tecnología como medio para la mejora del proceso de enseñanza-aprendizaje, ya sea a través del contacto físico en el aula o laboratorio, o por medio de sistemas virtuales en línea, tiene una potencialidad altamente positiva, haciendo posible profundizar la capacidad de asimilación de conceptos dando una nueva dimensión al aprendizaje significativo. En este trabajo, se exploran diferentes tecnologías útiles para la capacitación en metrología, y se realizan propuestas para el desarrollo de diferentes instrumentos virtuales en planillas Excel, como un recurso de fácil acceso por su masiva distribución en los ambientes educativos. Esta herramienta demostró su versatilidad tanto para el profesor como para el alumno, y su portabilidad permite una fácil migración entre diferentes plataformas con un simple intercambio de archivos. Cabe aclarar que el software utilizado para el desarrollo de los instrumentos virtuales ocupa un lugar privilegiado en la práctica metrológica dentro de los laboratorios de calibración, haciéndolo extremadamente competitivo, incluso frente a sus competidores gratuitos.

Legal metrology: Airport: When measurements harass passengers

The number of measurements performed in an airport is probably countless and of paramount importance for airport and flight security and safety. Measurements are performed following strict rules and best practice in metrology, otherwise our skies would not be as highly safe as they are. However, there is a small number of measurements, related to passengers' luggage that have a non-negligible and sometimes annoying impact on travelers and that are quite likely not performed in a totally fair and metrologically sound way.

Measurement uncertainty evaluation by kurtosis method at calibration of electrical resistance standards using a comparator

The article provides examples of the application of electrical resistance standards in metrological practice. Existing methods for their calibration are analyzed. It is established that calibration using a comparator is the most accurate and common method for calibrating electrical resistance standards.A model for transferring the size of the resistance unit in calibration of electrical resistance standards using a comparator is considered. An expression is given for the evaluation of the value of measurand. The procedure for estimating the expanded measurement uncertainty based on the kurtosis method is described, and the uncertainty budget is drawn up. An example of evaluation of the measurement uncertainty in calibration of the resistance coil P321 using a resistance comparator P3015 is given. The coincidence of the obtained results with those got using the Monte Carlo method is shown.

Fiducial Reference Measurements for validation of Sentinel-2 and Proba-V surface reflectance products

Many derived Earth Observation products share surface reflectance as a common step in their processing chains. This makes the maintenance and improvement of surface reflectance product quality of fundamental importance to ensure information derived from these downstream products can be trusted. Despite this, the literature is relatively light on the implementation of validation methodologies designed for surface reflectance. In response to the need to improve general EO validation methodologies, the concept of fiducial reference measurements (FRM) was created that would produce validation data that is fully characterised and independent, with associated uncertainties, and traceable to SI.This paper describes a field campaign designed to produce surface reflectance validation data, in line with the FRM ideology, for validating the Sentinel-2 L2A (S2) and Proba-V S1-TOC (Proba) surface reflectance products. The key methodological procedures are outlined in detail to facilitate uptake of FRM methods in future validation studies. These include the calibration and characterisation of field instruments, the field measurement protocol, and uncertainty propagation.Comparison of S2 with field measurements showed agreement within the stated uncertainties present for all bands and locations at the pixel and area scales. The Proba comparison results demonstrated a general disagreement within the stated uncertainties. However, there is a lack of uncertainty information provided by the product as well as publicly available product uncertainty requirements which mean that it is difficult to assess this fully. The aim of this practical demonstration of FRM-based surface reflectance validation, that utilises metrological practices for uncertainty characterisation, is to encourage the adoption of these procedures in future land surface reflectance validation studies and operational activities.

Special Issue on the Latest Research in Precision Engineering

Multidisciplinary study and practice of high-precision engineering, metrology, and manufacturing have made a direct contribution to industrial and economic development in the world, providing new value creation and enhancing productivity and product quality. This special issue focuses on the latest studies in the field of precision engineering. The special issue especially features advanced technologies in the manufacturing process, metrology, machine tools, machine elements, and nano/micro mechanisms. Besides these technologies, to enhance reliability and safety in the production processes, there is a need for usability and functionality based on IoT-related technology, which is represented by Industrie 4.0 or the Industrial Internet. Therefore, many researchers have now begun to focus on cyber-physical production systems (CPPS), which can detect anomalies and self-optimize the production process by comparing actual results extracted from sensors and simulation results. From this viewpoint, advanced research related to CPPS, such as simulation-based technique, sensor-based technology, and in-depth understanding and modeling of the manufacturing process, is covered in this special issue. In this special issue of IJAT, there are 14 research papers on precision-engineering-related topics as mentioned above. The papers, revised and extended according to the editors’ request, were originally presented at the 17th International Conference on Precision Engineering (ICPE2018), held in Kamakura, Japan, in 2018. We express our sincere thanks to the authors and reviewers for their meticulous work in helping publish this special issue. We hope these articles will encourage further research on precision engineering.

Zasady dobrej praktyki metrologicznej, zapewniające wiarygodne wyniki pomiarów struktury geometrycznej powierzchni

The most important factors influencing obtaining reliable results of surface structure measurements are presented. The article presents the rules for the selection of an appropriate measurement method adapted to the nature of the measured surface and the advantages, disadvantages and limitations of measuring instruments. Principles of good metrological practice during the preparation of the device for carrying out measurements and performing the analysis in order to calculate the parameters of the of the surface structure were discussed.

Toward a Classification of Partitioning Operations for Standardization of Geometrical Product Specifications and Verification

Partitioning is one of the four major operations used in the international standards issued by ISO/TC 213 on geometrical product specifications and verifications (GPS, for short). The ISO GPS standards define both tolerancing (for specification) and metrology (for verification) practices that are of critical importance to manufacturing industry. Collectively, these emerging ISO GPS standards have the potential to be some of the key enablers of digitization of manufacturing (also known as smart manufacturing, cyber-physical manufacturing, cyber-physical production systems, and Industrie 4.0). In simple terms, partitioning operations divide a surface (ideal or measured) into subsets that are then subjected to further GPS operations. This paper addresses the classification problem of partitioning operations to provide a science-based solution for the development of ISO GPS partitioning standards. Such a classification is considered to be one of the first tasks that must be completed before detailed standards on partitioning can be developed.