Prioritised multi‐response product screening using fractional factorial designs and order statistics

Abstract

Purpose

The purpose of this paper is to propose a manufacturing product‐screening methodology that will require minimal resource expenditures as well as succinct improvement tools based on multi‐response prioritisation.

Design/methodology/approach

A six‐step methodology is overviewed that relies on the sampling efficiency of fractional factorial designs introduced and recommended by Dr G. Taguchi. Moreover, the multi‐response optimisation approach based on the super‐ranking concept is expanded to the more pragmatic situation where prioritising of the implicated responses is imperative. Theoretical developments address the on‐going research issue of saturated and unreplicated fractional‐factorial designs. The methodology promotes the “user‐friendly” incorporation of assigned preference weights on the studied responses. Test efficiency is improved by concise rank ordering. This technique is accomplished by adopting the powerful rank‐sum inference method of Wilcoxon‐Mann‐Whitney.

Findings

Two real‐life case studies complement the proposed technique. The first discusses a production problem on manufacturing disposable shavers. Injection moulding data for factors such as handle weight, two associated critical handle dimensions and a single mechanical property undergo preferential multi‐response improvement based on working specification standards. This case shows that regardless of fluctuations incurred by four different sources of response prioritisation, only injection speed endures high‐statistical significance for all four cases out of the seven considered production factors. Similarly, the technique identifies a single active factor in a foil manufacturing optimisation of three traits among seven examined effects.

Originality/value

This investigation suggests a technique that targets the needs of manufacturing managers and engineers for “quick‐and‐robust” decision making in preferential product improvement. This is achieved by conjoining orthogonal arrays with a well‐established non‐parametric comparison test. A version of the super‐ranking concept is adapted for the weighted multi‐response optimisation case.

Citation

Besseris, G.J. (2009), "Prioritised multi‐response product screening using fractional factorial designs and order statistics", Journal of Manufacturing Technology Management, Vol. 20 No. 4, pp. 513-532. https://doi.org/10.1108/17410380910953766