Text V dimensional metrology

Dimensional metrology is the measurement of size and distance, along with the study of measurement techniques and the development of new technology, to increase the accuracy of measurements. Humans have been on a quest to measure objects and make those measurements as precise as possible for thousands of years, as evidenced by numerous objects in the historical record that show how previous societies measured and recorded measurements. Several organizations dedicated to measurement and standardization have dimensional metrology divisions.

One aspect of dimensional metrology is the development of standardized units for measurements and specific practices for taking and recording measurements. The metric system, for example, is a standard used in many regions of the world to measure dimensions. Standard techniques and practices are important, especially when it comes to declaring measurements on technical documents. Any reader should know how the measurements were performed so he can precisely replicate them.

The development of tools for measurement is another component of dimensional metrology. Devices for measuring can include everything from tape measures to levels. It is possible to measure numerous angles and components of a product, from the holes tapped for the screws to the angle of the curvature on the lid. Dimensional metrology allows for very precise measurements on projects with minimal tolerance for error, like machined parts that must fit exactly into a system for functionality.

The actual practice of measuring includes not just taking measurements in a standardized way with the right instruments, but also maintaining good conditions for measuring. Maintenance of measuring equipment is important, as is regular calibration to ensure that measurements are accurate. A small margin of error can become large over time, especially on a major project. Manufacturers must develop high performance measuring tools along with methods for calibrating them and checking measurements for accuracy.

Many researchers in the field of dimensional metrology are engineers, specializing in a variety of subtopics. Companies that manufacture measuring supplies can also produce instruments for collecting and recording other kinds of data. These can include mass spectrometers for analyzing the chemical makeup of products, scales for assessing weight, and tools for measuring volume, among many others. Working in this field requires excellent observational skills, a sharp attention to detail, and the patience to refine projects until they are perfect. Math and science skills are also critical, as dimensional metrology relies heavily on formulas and advanced scientific concepts for precision. Specialists can work for private companies, organizations that set and maintain standards, and government agencies.

Text VI dimensional metrology group

The Dimensional Metrology Group in the Semiconductor & Dimensional Metrology Division of the Physical Measurement Laboratory (PML) at the National Institute of Standards and Technology (NIST) realizes and disseminates the SI units of length, concentrates on dimensional measurements in the range of one millimeter to several kilometers, and provides the delivery of those measurements, standards and infrastructural technology services that promote U.S. innovation and industrial competitiveness. They use general and special-purpose feature and coordinate measuring systems for measurements of complex shape, such as, turbine blades, threaded fasteners, and gears, and coordinate measuring machines and frameless coordinate length-metrology systems for mechanical-probe, laser-ranging, theodolite, and related interferometric systems. The group performs research into advancing the state of the art of coordinate dimensional metrology and developing a method to quantify the performance evaluation of dimensional measurement instrumentation. It actively supports international and national dimensional metrology standards committees by its participation and leadership and with emphasis on rigorous uncertainty evaluation.

The primary mission of the Dimensional Metrology Group is to provide US industry with practical access to the unit of length through high accuracy calibrations. The group specializes in measurements on objects approximately one meter in length up to kilometers. The group’s calibrations serve the aerospace, land surveying, petroleum gauging, law enforcement, metrology instrumentation developers, and large scale manufacturing industries.

Calibrations are available to the industrial public on a fixed fee basis. Special tests are on a fee for service basis; the group’s facilities are available to industry to test new measurement technologies or prototype metrology instruments. Tests are run by NIST staff with the input of the LSCM Group’s customer or their designate.

The Dimensional Metrology Group strives to leverage its metrological expertise by participating in documentary metrology standards. National (ANSI) and international (ISO) standard writing bodies can direct how entire industries specify and test their products. The Dimensional Metrology Group participates in these standard writing bodies to provide metrological expertise that assists in producing technically significant documents that are balanced for both instrument manufacturers and for industrial users.

The benefits of standardized specifications and testing procedures are many. Well written standards have significant positive externalities to industry. By standardizing specifications manufacturers can avoid the significant costs of individualized idiosyncratic testing that would otherwise be requested from each customer. Users of standardized technology benefit by comparing products from different manufacturers to common specifications and hence can purchase products that are best suited for their needs.

The entire metrology industry benefits from standardization because it lowers barriers to adopting new technology by providing “expert” information and specifications. A well-vetted standard with high intellectual content protects customers from their own inexperience and through the experience, expertise, and integrity of the standards writing committee, increases confidence to adopt new technology.

The Dimensional Metrology conducts research to lower the uncertainty of its calibrations, to develop new measurement technology, and to advance national and international standards. The group actively collaborates with universities, other national laboratories, and industrial partners.