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Physical Measurement Laboratory / Quantum Measurement Division

Mass and Force Group

Projects/Programs

Displaying 1 - 8 of 8
SI Base Units chart

Calibration of Force Transducers

Ongoing
The calibration report describes the relationship between the applied force and the measured deformation, either in electrical or mechanical units. A transducer can be calibrated using (1) a readout device furnished by the customer, in which case the transducer and the readout device are calibrated
traceability chain illustration

Calibration of Mass Standards

Ongoing
Redefinition of the Kilogram and Consensus Value of the Kilogram The unit of mass was redefined in May 2019 as part of a general revision to the International System of Units (SI). See SI Redefinition. The kilogram is now defined by the Planck constant. The International Prototype Kilogram (IPK) no
Anechoic-Chamber-400 X 324

Dynamic Mechanical Metrology: Acceleration, Force, and Acoustics

Ongoing
The Dynamic Mechanical Metrology Project develops standards and provides calibrations for SI-traceable acceleration, acoustical and dynamic force metrology. We develop improved reference standards and calibration techniques, sensor-embedded standards, calibration techniques for new technologies, and
weighing device

National Type Evaluation Program (NTEP)

Ongoing
NTEP requires industry to submit prototype weighing devices for evaluation to determine whether or not it meets the uncertainties which are related to tolerances associated with the intended final use in the marketplace. All devices sold in the United States for "legal for trade" purposes must pass
mass-in-vacuum precision mass comparator

NIST Mise en Pratique of the New Kilogram Definition

Ongoing
Realization Since the redefinition of the kilogram, the Mass and Force Group has been intricately involved with the NIST realization of mass via the Kibble balance. By maintaining traceability to the International Prototype Kilogram (IPK) via the 2019 calibration of NIST National Prototype K20, the
DPO sensor

Quantifying the environmental contributions to mass change

Ongoing
Experiments using two types of centimeter scale oscillators are described: the double paddle oscillator (DPO) and a commercial quartz crystal microbalance (QCM). Double Paddle Oscillator (DPO) Since mass changes are mostly on the surface of mass artifacts, we have implemented a micro-weighing sensor
deadweight

Reconditioning of the 4.45 MN deadweight machine

Completed
The 4.45 MN DWM has been in use in the NIST Force Laboratory since 1965 and is frequently characterized as the largest deadweight force standard in the world. Thousands of measurements through many force calibrations have been performed over the lifespan of the machine. The machine was the
relative uncertainty, force and mass

Small Mass and Small Force Metrology at NIST

Ongoing
Project 1: The electronic milligram. As a result of kilogram redefinition within the SI, it may be possible to realize mass at the milligram level and below using electrical measurements. To this end, the NIST Electrostatic Force Balance (EFB) has been used to measure the mass of artifacts spanning