Optimum evaluation performance of adaptive X-bar control charts

Abstract

ABSTRACT Control charts are useful tools to regulate processes. Thereby the quality of products and services is enhanced which makes them more attractive to the customers. While fixed-parameter X-bar charts have been regularly utilized in manufacturing systems since 1931, their incompetent effectiveness in the discovery of small-to-moderate shifts in mean has proven to be a major limitation. A systematic study providing in-depth information on the effectiveness of adaptive X-bar control charts at optimal points within the response space was needed to resolve this issue. While previous research used a forward perspective, evaluating the effectiveness of adaptive models for a specified range of design parameters, we utilized a reverse viewpoint to investigate all feasible sets of design parameters. It allowed obtaining the minimum values for three different performance measures using single-objective and multi-objective optimizations. The guideline provides quality engineers with an in-depth awareness on optimal points to select an appropriate adaptive model.