Some Considerations for a Measurement Strategy for Circular Features
Howard H. Harary, C Buchard, P L heritier, J Dufraigne, P Chollet
The careful study of manufactured parts is a prerequisite for their intelligent inspection. For this study, we conducted a survey of the processes for making holes by manufacturing a set of test parts using ten different machining processes. The holes were measured at high density and high accuracy to produce detailed pictures of the forms of the holes ? characteristic process signatures were found. The full data sets were then sampled with the low numbers of sampling points typical of process control and quality assurance using coordinate measuring machines in industry. The least-squares radii and center position of sampled data sets were compared to those parameters calculated for the full data set. These comparisons will be used to make recommendations to manufacturers for adequate, economical sampling densities to achieve desired inspection tolerances. The present study compliments previous studies because it is based on real measurement data, and not simulations. The processing and use of our data sets as reference data sets with well known least-squares radii and center position will also be discussed.
Proceedings of American Society for Precision Engineering