A methodology based on Fuzzy Extended Quality Function Deployment for determining optimal engineering characteristics in product-service system design

Manufacturers are now undergoing a transition from only selling tangible products to implementing product-service system (PSS) strategy. A PSS is a marketable set of products and services capable of jointly fulfilling customer needs. The empirical and theoretical contributions have been made in this field, but there is a lack of engineering methods for PSS design. In this paper, the authors define the design parameters of the products and services in a PSS as engineering characteristics (ECs), and develop a systematic approach based on Fuzzy Extended Quality Function Deployment to determine ECs effectively. Fuzzy set theory is applied to deal with the impreciseness and fuzziness of customer needs and other uncertainty on design. The extension of Quality Function Deployment is build to address three major problems in PSS design: There is not appreciate methods for representing service in an engineering way; The mutual relationship between product ECs and service ECs must be explored; It is imperative to harmonize different opinions of the stakeholders in a PSS on the design. Then, the optimal ECs for a PSS are obtained by a mathematical model which maximizes customer satisfaction with limited resource constraints. Consequently, the systematic approach is helpful for companies to develop a customer-centered and affordable PSS. An illustrative example is presented to validate the applicability of the methodology.