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Step 1: Preparation for the Study
Objective:
Determine which process parameters will be used for the rest of the
study.
Process:
Determine what measurement system is to be studied. This
includes the instrument and the test procedure.
Document the test procedure.
Determine the number of operators (k), the number of sample parts
(n), and the number of repeated readings (r). As a rule of thumb, you
might choose 3 operators, 4 to 10 sample parts, and 3 to 6 repeated
readings.
Note: the greater the number of operators or parts or readings, the
greater the confidence, the greater the price - so you decide how
the confidence should be utilized.
Determine who the operators will be. The operators chosen should
be selected from those who are trained/certified on the
measurement system.
Determine what samples will be used and where the samples will
come from. The sample parts must come from an existing
process and represent its entire operating range.
Several methods can be used which will ensure randomly distributed
sample parts. The most common method includes taking samples
on different days during different shifts.
