Gage R&R is an estimate of the combined variation of repeatability and reproducibility. Stated another way, GRR is the variance equal to the sum of within-system and between-system variances.
Sensitivity
Sensitivity is the smallest input that results in a detectable (usable) output signal. It is the responsiveness of the measurement system to changes in measured feature. Sensitivity is determined by gage design (discrimination), inherent quality (OEM), in-service maintenance, and the operating condition of the instrument and standard. It is always reported as a unit of measure.
Factors that affect sensitivity include:
Ability to dampen an instrument
Skill of operator
Repeatability of the measuring device
Ability to provide drift free operation in the case of electronic or
pneumatic gages
Conditions under which the instrument is being used such as ambient air, dirt, humidity.
Consistency in GRR
Consistency is the difference in the variation of the measurements taken over time. It may be viewed as repeatability over time.
Factors impacting consistency are special causes of variation such as:
Temperature of parts
Warm up required for electronic equipment
Worn equipment
Uniformity
Uniformity is the difference in variation throughout the operating range of the gage. It may be considered to be the homogeneity (sameness) of the repeatability over size.
Factors impacting uniformity include:
Fixture allows smaller/larger sizes to position differently
Poor readability on the scale
Parallax in reading
source of GRR: Analysis of measurement systems
