Fuzzy Approaches for Constructing House of Quality in QFD and Its Applications: A Group Decision-Making Method

Quality function deployment (QFD) is a useful planning approach for constructing new product designs or modifying existing products. The approach has been widely adopted in various applications. For QFD processes, the house of quality (HOQ) is first constructed to describe customer requirements (CRs) and their importance, design requirements (DRs), the relationships between CRs and DRs, and the correlations among DRs. This study proposes a systematic procedure for constructing the HOQ and describes its application from a group decision-making (GDM) perspective. Considering the imprecise information in the design stage, fuzzy set theory is employed to develop fuzzy approaches for constructing the HOQ. In practical applications, a QFD team is usually organized to collect relevant information; therefore, GDM approaches are incorporated into the construction process of the HOQ. To reflect the differences between decision-makers' evaluations of elements in the HOQ, various ways of assessing the components of the HOQ are allowed. A modified fuzzy clustering approach is proposed for finding the consensus of the QFD team. Based on the established HOQ, approaches are presented for prioritizing DRs as a reference for allocating internal resources to appropriate DRs in order to optimally satisfy CRs. A numerical example is used to demonstrate the applicability of the proposed approaches.