IMPROVEMENT OF A DIMENSIONAL MEASUREMENT PROCESS USING TAGUCHI ROBUST DESIGNS, by Chih-Young Lin, Chien-Long Hong, and Jiing-Yih Lai, Mechanical Engineering Department, National Central University, Chung-Li 320, Taiwan, Republic of China

Abstract

Statistical process control (SPC) has been used extensively in industry for monitoring the product quality. The variations of measured product characteristics, however, come not only from the manufacturing process but also from the measurement process. Large measurement variability may cause errors in SPC results and, hence, lead to wrong interpretation of the product quality. The objective of this work was to conduct a robust design study to investigate the effects of measurement factors, which would lead to a reduction in the measurement variability. Repeatability and reproducibility studies verified the success of the proposed strategy. Process capability analyses confirmed the net effect of the reduced measurement variability on the product variability.