Evaluation of “Design Loops” to Support the Design of Product Service Systems: A Case Study of a Helium Liquefier

In this paper a specific evaluation for the PSS during the early design phase is presented, taking into account:  the scenarios that supports the definition of the architecture of the whole system and the interactions between the user and the system  the performance of the considered system assess with specific PSS criteria (economical and environmental) Our proposition consists in the evaluation of the design loops that are constructed jointly with the scenarios describing activities and with the PSS architecture. This evaluation phase is part of a methodology that is being developed to design global and optimized PSS.