Metrology: The Scientific Study of Measurement (Part 2)

Introduction – The Future of Metrology

Last time, we walked you through the important past of the field of metrology. Today, we would like to look to the present and future of the field and discuss some of the major ways metrology continues to advance. From improved standardization to the development of actual robots that help with measurement processes, the future of metrology is bright. At Higher Precision, we have our eyes on the future, because we know that staying up to date on progress and advancements within measurement is what matters to you. We hope to celebrate together the incredible feats that metrologists all over the world continue to accomplish each day. 

A Major Milestone in Metrology

In November of 2018, a major milestone in the field of metrology occurred. Representatives from 60 different countries gathered together in Versailles, France to rethink the basis of the international system of units. Following a vote, metrology experts from across the world approved a new system that officially bases measurement on constants found in physical science, such as the speed of light or the behavior of mass and energy. Not to worry. The way you take measurements in your daily life has not changed. However, within the broader world of science, this milestone was groundbreaking. Where the original metric system depended on natural occurring phenomena, such as a meter being one ten-millionth the distance between the North Pole and the equator, or a kilogram being the mass of one liter of water, these physical objects were at risk of wearing out or changing. Now, measurement standards are entirely based on unchanging constants that are found in physical science and grounded in natural laws. The remaining standardization decisions were finalized in May of 2019. This step forward helped to revolutionize metrology by allowing for scalability and accuracy all over the world without reliance on representative physical artifacts. 

Recognized Units in Metrology

There are seven base units that define measurement. These include: time (second), distance (meter), mass (kilogram), electric current (ampere), temperature (kelvin), the amount of a substance (mole), and luminous intensity (candela). These seven units are independent of each other and determined from their corresponding defining constant. All other measurement units that you may have heard of can be derived from these base units of measurement. 

Metrology Today

So now that we have a handle on where metrology came from and the journey it took to get to a place of true standardization, let’s talk about how metrology as a field is structured today. There are three main subfields in metrology: scientific or fundamental metrology; applied, technical or industrial metrology; and legal metrology. There are also several metrological institutes that maintain and regulate metrological standards. These organizations can be international or national. Finally, metrology today requires ongoing understanding of standards, calibration methods, and uncertainty or traceability variables in order to continue having precise and accurate measurement. Let’s learn some more about all of these parts of the metrology world.

Scientific or Fundamental Metrology

As the top level of metrology, fundamental metrology aims for the highest levels of accuracy and precision. Within the subfield of fundamental or scientific metrology, you will find how units of measurement are established and unit standards are determined. Tasked with the overall organization and development of measurement, scientific metrology often involves detailed research. The development of new technologies also falls under this subfield in metrology, with involvement in a number of industries including healthcare, commercial products, and government.

Applied, Technical, or Industrial Metrology

Industrial metrology involves the application of metrology within manufacturing, with a focus on ensuring quality and suitability of certain instruments. Essentially all products made today require some degree of technical metrology when they are made. Being able to trace measurements back to specific devices and to particular standards is an important part of maintaining consistency. Essentially, industrial metrology makes sure that all types of measurement instruments are functioning how they are supposed to function. 

Legal Metrology

Legal metrology is the subfield of metrology that handles issues relating to the economic world and the application of legal requirements to measurements and tools. Inaccurate measurement errors can have major effects on the financial or physical well-being of individuals and industries alike. Legal metrology focuses on the legislation relating to precise applications of measurements. Most countries have some type of metrological legislation in order to have a basis for outcomes when errors occur. Legal metrology is organized around these legislative concerns.

Metrological Institutes

The world of metrology requires constant and ongoing regulation. Various institutes at the international and national level work together to ensure that the field of metrology runs smoothly across the entire world. These different groups help maintain standards while also promoting improvement and progress in a field that is pivotal to daily operations everywhere.

International Metrological Institutes

At the original Meter Convention in 1875, three main international organizations were created with the purpose of overseeing the world of metrology longer term. The General Conference on Weights and Measures was set as a gathering place for a representative group of members from various locations who are central in making metrology-related decisions. The conference meets every four to six years and members discuss various aspects of metrology while supporting new developments as needed. The International Committee for Weights and Measures is a group of individuals nominated at the General Conference on Weights and Measures in order to oversee and advise. It houses ten different consultative committees that each focuses on a specific area of metrology. Finally, the International Bureau of Weights and Measures serves as the headquarters for the physical artifacts that represent the meter and kilogram, and they work closely with the other two organizations regarding conferences and administrative matters.

There are three other main international metrological institutes including the International Organization of Legal Metrology, the International Laboratory Accreditation Cooperation, and the Joint Committee for Guides in Metrology. The International Organization of Legal Metrology started in 1955 and aims to build collaboration and consistency around legal metrology in order to facilitate international trading. The International Laboratory Accreditation Cooperation began in 1977 and has the central purpose of standardizing the procedures of accreditation and calibration across different countries. Finally, the Joint Committee for Guides in Metrology is made up of two subgroups tasked with the creation and maintenance of the Guide to the Expression of Uncertainty in Measurement (GUM) and the International Vocabulary of Metrology – Basic and General Concepts and Associated Terms (VIM).

National Metrological Institutes

On the national level, different metrology institutes or systems are tasked with implementing a consistent measurement infrastructure. These institutes may oversee setting standards, ensuring accuracy, determining comparability, assessing reliability, and more. More specifically, metrology institutes, calibration laboratories, and accreditation bodies are responsible for making sure these different tasks get done. A national metrology institute engages in scientific metrology and the maintenance of standards. These groups ensure that there is a calibration hierarchy that allows each measurement standard to be traceable. Calibration laboratories are where calibration services take place, linking the national metrology institute to the industrial application. Finally, accreditation bodies are those organizations who have been deemed competent to provide metrology services by being fully compliant with international requirements. These bodies remain separated from other national institutions in order to help guarantee objective and credible accreditation. 

Factors of Metrology

The field, study, and practice of metrology involves a number of relevant factors that are all required for accurate measurement across contexts. The various international and national institutes work together to oversee these factors, regulate their application, study their reliability and change, and discuss their relevance. 

Standards

A standard is what defines the relationship between a physical quantity and a unit of measurement. As discussed, standards for units of measurement are now all based on constants found in nature, but once, they were connected to specific physical objects, such as the distance between the North Pole and the equator. A standard can be a specific experiment, system, or object, as long as it is representative of a unit of measurement. Within metrology there are primary, secondary, and working standards within a hierarchy. Primary standards are at the top of the hierarchy and do not require reference back to any other standard, as they themselves are the original representation of the unit. Secondary standards are then calibrated against the original primary standard and are used as the go-between to create lower level standards. The working standards are calibrated against secondary standards and are then used in order to check various measurement instruments or tools.

Calibration and Traceability

Calibration and traceability are separate factors, but work closely together. Traceability is the idea of being able to find the chain of reference from any one measurement to another. This allows for accurate comparisons across time and space between measurements. Traceability also ensures that metrology-based information and tools are being used appropriately and precisely. Calibration is the actual establishment of one measurement instrument against another using a particular standard. This operation establishes the relationship between two measurements, thus allowing the connection to be traceable. Calibration is also important because it makes the eventual measurement data points standard between instruments, determines accuracy, and creates reliability. Traceability starts at the industry application and testing laboratories, goes up to calibration laboratories, moves further to national metrology institutes, and then finally goes to international standards. Calibration on the other hand begins with the international standards, moves down to the national metrology institutes, continues on to calibration laboratories, and eventually lands in the industry applications and testing laboratories. 

Uncertainty and Environmental Variables

Despite the organization and seriousness of the various levels of metrological oversight, standards, traceability, and calibration, there will always remain a certain degree of uncertainty when completing lower level, applied measurements. Measurement uncertainty refers to the value associated with a specific amount of doubt within each measurement. The idea of measurement uncertainty includes both the width of the uncertainty variable and the confidence level. The width of the uncertainty variable is the span of values that the true measurement is likely within, and the confidence level is the degree of confidence that the true measurement does fall within the span of values. Statistical analysis can be used to determine measurement uncertainty accounting for calibration and potential measurement error.

The Future of Metrology

Metrology is at the heard of innovation and progress. While anchored in a long and important history, metrology also holds an incredible future full of improvement and benefit. The science of measurement is far from old news as humans make remarkable advancements in technology, medicine, and functioning. Businesses and industries all over are constantly looking for methods to improve efficiency and help individuals heal from disease or live a more functional lifestyle. Additionally, sustainability is more important than ever, and new metrology trends will aim to improve sustainable science without sacrificing accuracy. From new measurement systems and tools to better accessibility with lowered costs, the future of metrology is full of possibilities.

Recognition and Celebration of Metrology

Despite the interwoven nature of metrology in our daily lives, the average person may not think much about metrology as a field. Importantly, World Metrology Day falls on May 20 every year celebrating the original Meter Convention. This annual event is paired with a convention organized to help continue global collaboration and recognition. The 2023 theme for World Metrology day is “measurements supporting the global food system.” This nod to one of the infinite ways in which metrology impacts each of us is a wonderful emphasis on a relevant measurement topic. 

Trends to Expect in Metrology Over Time 

The increase in popularity and availability of micro and nanotechnology is bound to improve the efficiency of metrological applications. A range of industries including construction, digital communication, and medicine are working to downsize through developing more lightweight and ergonomically effective measurement methods. Similarly, metrology equipment will be reducing margins of error through the application of microscopic components and innovative materials like aerogel or graphene. New tools, improved efficiency, and better measurement methods can only mean one thing – lower cost. By improving metrological knowledge, the field will help to decrease the costs of machines over time by improving durability and reducing error. Additionally, with efforts to refine the way users interface with tools, improve the degree of portability of these tools, and increase the intuitive nature of how tools work, the field of metrology is making strides toward making measurement power more accessible to those who need it.

Speed, accuracy, and integration will be built into the future of metrology as well. While huge strides have already been made regarding these factors, new technology and major digitization of the field only means even more progress to come. The on the ground tools currently being designed will bring an increase in speed in the way motors operate, the way calibration is completed, and the way scanning takes place. Metrology computers can already process thousands of data point in just minutes, a feat we could not have predicted just a few decades ago. Certainly the future will show us even speedier processing. Additionally, that increase in speed will not impact accuracy, which is also on an upward trajectory. Considerable advancements in engineering and multi-sensor devices have pushed precision ahead of its time, allowing metrologists to assess multiple data channels, rechecking data at twice the speed. Finally, integration of digital metrology into cloud based storage opens up a world of options in terms of design, computing, and maintenance. Digital measurement methods are also easier to use which helps increase accessibility and collaboration. Just think what can be accomplished as metrology fine tools its hold in the digital realm. 

New Directions in Metrology

Advancements such as optical technology, lasers, and three-dimensional scanners continue to have a major impact on the way metrology works. The field is moving forward with innovative systems and technological improvements. Eventually, fully automated measurement systems may incrementally take over human operation of metrology tools. Intuitive software may be able to help metrologists everywhere flexibly adapt to on site issues of measurement. Measurement systems may soon be able to automatically determine environmental specific needs in order to complete complex measurements at the touch of a button. In many ways, the process of measurement is already more automated than ever before with tools like digital data conversion and measurement robots working alongside humans.

Metrology has begun to include the frequent use of cobots. Cobots are collaborative robots that work to help automate measurement and make high level metrology more accessible for businesses and industries all over the world. Cobots are specifically designed to share space with human workers, to be cost effective, and to vastly enhance measurement possibilities. Built in a range of sizes to meet your needs, cobots are the productivity gold standard and will help manufacturers meet performance objective as well as match customer demands, all while improving quality of work. These machines are easy to program, quick to set up, collaborative and safe to use, and come with flexible automation options so that the robot adapts to your needs, not the other way around. Innovative automated systems like measurement robots are only going to become more useful and more common over time in the world of metrology.

Conclusion

Metrology is both simple and complex. It has a place in so many aspects of our shared history and our daily functioning. Keeping up to date on how we got here as a field and where we are going in the future is an important part of working in the field of metrology. With the technological advancements already in process today, we are confident that we can accomplish amazing goals. At Higher Precision we are proud to keep the excitement alive for what’s to come within the field of metrology. Contact us today to learn more about how to be a part of the metrology family!

---

FREQUENTLY ASKED QUESTIONS

Has metrology made any recent advancements?

Metrology has made a number of advancements since its inception as well as more recently. Specifically, one major milestone in the field of metrology occurred in November of 2018. At this time, representatives from 60 different countries across the world gathered together in Versailles, France to vote on defining new systems of measurement standards. This new system officially connected unit standards of measurement back to physical properties of the natural world that are subject to natural law. For example, the meter was officially defined by the distance light travels in a vacuum over the time period of one second. Before this monumental shift, the original meter was defined by a physical artifact stored in the International Bureau of Weights and Measures, which was subject to wear over time. While the actual length of this unit remained unchanged, the basis used to define the primary standards of measurement will remain constant and reliable over time.

What factors are present in the study of metrology?

There are four main factors or concepts that are central to the history of and study of metrology. These factors include standards, calibration, traceability, and uncertainty. Standards are the objects or systems that represent the primary quantity on which a measurement unit is based. Standards for the metric system are all currently based on physical properties of the natural world and will remain constant over time. Calibration is the process of establishing one measurement instrument against another, based on the standards of that particular unit of measurement. Calibrating two tools with one another ensures that each one is capable of identical and accurate measurements. Traceability is the idea of being able to trace one measurement back to another, making connections between calibrated instruments. This is particularly important in establishing accuracy and consistency among measurements taken across the world. Finally, uncertainty refers to the degree of potential error found within each measurement due to environmental variables, operator differences, or other unknown factors. Uncertainty can be calculated and protected against.

What does the future of metrology look like?

Metrology is constantly progressing and heading in incredible new directions. With advancements like three-dimensional scanners, laser application, and optical technology, the way in which measurements take place have become more precise. Improving precision and accuracy is one area of metrological work, but helping to increase measurement speed as well as accessibility to better tooling are also important aspects of progress. Higher automation is a major area of future possibilities for metrology. Already there exist robots that can help with both the manufacturing of products and the measurement stages of productions. Collaborative robots, known as cobots are more and more common in use and will be changing metrology for the better. These robots can work side-by-side with human operators, simultaneously improving accuracy and speed while helping the operator complete tasks. Innovative automated measurement systems like these hold so much potential and will be integral to the future of metrology.

GLOSSARY TERMS

Cobots

Cobots are collaborative robots that complete automated measurement procedures alongside human operators. A cobot is made up of a lightweight robot arm that is capable of assisting with manufacturing, assembling, and packing tasks in addition to taking part in the actual process of industrial measurement. Cobots are the metrology of the future in action today. These machines streamline the measurement process and can help to transform the work being done at the scientific and industrial levels.

Metrological Institute

Metrological institutes can be national or international and consist of the overseeing organizations or groups of people that regulate and maintain the world of measurement as we know it. Metrology as a field is based on a strong foundation of agreement, collaboration, and consistency when it comes to maintaining the rigorous standards of measurement. Since worldwide consistency of any sort requires a great deal of communication, the metrological institutes are in place to ensure smooth maintenance of measurement systems. The international and national metrological institutes also provide a gathering space for innovation and progress within the field of metrology.

Standard

A standard is the specific system, idea, or object that defines the relation between a unit of measurement and a quantity. As of today, all of the seven basic units of measurement are connected to standards based on the laws of nature and the physical world. For example, length or distance is defined by the standard of the distance light travels over the course of one second. Standards are hierarchical. Primary standards are the actual reference used to define the unit. Secondary standards are objects that are calibrated against the primary standard and used to create lower level standards. Finally, working standards are initially calibrated again secondary standards and then used in more daily applications of measurement.

Traceability

the property of a measurement in which the result can be linked to a standard reference (such as NIST) through a documented unbroken chain of calibrations, each contributing to the measurement uncertainty

Uncertainty

Uncertainty is the value of naturally occurring and accounted for disparity between any measurement that is taken and the absolute true measurement. Whether due to unknown or known environmental factors, unavoidable human differences in operation, or some other unnamed quality, measurement uncertainty is often inevitable and therefore important to account for within the measurement process. Uncertainty is represented by the width of the uncertainty variable, or the span of valued a true measurement likely falls within, and the confidence level, or the degree of confidence that the value falls within that span.

World Metrology Day

World Metrology Day falls on May 20th each year and represents a celebration of the original Meter Convention where the metric system of measurement was initially defined. Each year, World Metrology Day involves a metrology convention that promotes collaboration and progress internationally to help further the field and celebrate the impact metrology has on a wide range of areas. In 2023, the theme for World Metrology Day is “measurements supporting the global food system.” Metrologists from all over the world will gather together to share findings, discuss innovations, and continue to build a better future for metrology and the world.