A QFD-based approach to support sustainable product-service systems conceptual design

During the design process of product-service systems (PSS) particular attention must be placed on sustainability, since the current models do not completely support the generation of sustainable PSS solutions. New methods to investigate PSS requirements analysis, evaluation, and conceptual design stages according to sustainability principles are needed. In this paper, an approach based on quality function deployment (QFD) is proposed to support PSS design. QFD is applied to translate stakeholders' requirements in the three sustainability dimensions into engineering metrics of products and services. QFD is also applied to deploy PSS functions and to support the conceptual development. Fuzzy analytic hierarchy process (FAHP) is used to prioritize the stakeholders' requirements in the three sustainability dimensions, and the fuzzy set theory is considered to reduce the vagueness and uncertainty during the process. The proposed approach is applied in an illustrative case for the conceptual design of a bike-sharing system. The suggested approach aims to contribute to the theory development as well as for practitioners. Firstly, it allows integrating the sustainability principles since the requirements elicitation stage, considering all stakeholders involved in the offer. Secondly, the requirements evaluation considering FAHP allows prioritizing the sustainability requirements dealing with uncertainty and vagueness. Finally, it helps to obtain more realistic results by integrating fuzzy decision-making into QFD. In future research, the integration of the Theory of Inventive Problem Solving (TRIZ) in the proposed approach will be investigated as well as the evaluation of different PSS concepts according to their sustainability potential.