PSS solution evaluation considering sustainability under hybrid uncertain environments

• Product service system has a potential to enhance competitiveness and contribute to sustainability.
• This paper aims to evaluate PSS in the early design stages considering sustainability.
• All of the three pillars of sustainability are considered in the evaluation.
• Both fuzziness and randomness are considered in the evaluation.

In order to deal with resource shortage and environmental deterioration, product service system (PSS) are proposed as a sustainable development concept. Careful evaluation in the earlier design stages must be performed before putting a PSS design solution into practice in order to guarantee the sustainability. Due to the reason that sustainability involves many factors and PSS is a complex system with long lifespan, the sustainability criteria will be of great quantity and various measurements. This paper aims to deal with two issues: (1) how to choose the sustainability criteria (2) and how to deal with uncertain factors when measuring these criteria. The zigzag mapping process is adopted to help decision makers to obtain criteria from the customer domain to function domain. The customer domain is modified to include the economic, environmental and social aspects of sustainability. To deal with uncertain factors, the Information Axiom is extended in the hybrid uncertain environments characterized by fuzziness and randomness co-existing. The design range is modeled as a fuzzy variable and the system range is modeled as a random variable. Thus the information content calculating involves integrals with fuzzy boundaries. A fuzzy simulation algorithm is constructed to calculate this kind of integrals. Two case studies are illustrated to highlight the effectiveness and accuracy of the proposed approach. The results show that the proposed method could reflect the judgements of decision makers more precisely, and make use of evaluation information more comprehensively. The results also show that use-oriented PSS is easy to be influenced by the social aspect of sustainability, while product-oriented PSS is easy to be influenced by the economic aspect of sustainability.