Quality utility - A compromise programming approach to robust design

In robust design, associated with each quality characteristic, the design o bjective often involves multiple aspects such as ''bringing the mean of per formance on target" and "minimizing the variations." Current ways of handli ng these multiple aspects using either the Taguchi's signal-to-noise ratio or the weighted-slim method pre not adequate. In this paper we solve bi-obj ective robust design problems from a utility perspective by following upon the recent developments on relating utility function optimization to a Comp romise Programming (CP) method. A robust design procedure is developed to a llow a designer to express his/her preference structure of multiple aspects of robust design. The CP approach, i.e., the Tchebycheff method, is then u sed to determine the robust design solution which is guaranteed to belong t o the set of efficient solutions (Pareto points). The quality utility at th e candidate solution is represented by means of a quadratic function in a c ertain sense equivalent to the weighted Tchebycheff metric. The obtained ut ility function can be used to explore the set of efficient solutions in a n eighborhood of the candidate solution. The iterative nature of our proposed procedure will assist decision making in quality engineering and the appli cations of robust design.