Quality Evaluation of a Manufactured Product with Multiple Characteristics

摘要

A majority of manufactured products have many quality characteristics that are important to the customer. To assess or evaluate the capability of a manufactured product with multiple characteristics, the quality characteristics need to be determined in advance and some characteristics can be correlated with each other. Also, the specification limits of the quality characteristics can be one-sided or two-sided. In order to deal with such multivariate data, there is a need to develop a new approach. In this study, the geometric distance variable is used to combine the correlated or uncorrelated quality characteristics. Then, the Luceno capability index is used to summarize the performance for each geometric distance variable. Finally, a composite capability index, MC_(pc), composed of several univariate capability indices, is proposed to analyze the capability of a manufactured product with multiple characteristics. In addition, the probability of the product non-conforming is also proposed. The application of the proposed methodology to a real-life case study is presented.