Concept selection of the automated inspection and maintenance test unit for the EU DEMO using a novel fuzzy-based decision support tool

Systems Engineering (SE) allows addressing the design of complex systems from a holistic standpoint, starting from the early stage until the end of its lifetime. Using a SE approach, all the stakeholders’ needs can be considered, encompassing requirements coming from all the different fields connected to design. Adopting SE, the ranking of the proposed design alternatives can be carried out using Multi-Criteria Decision Making (MCDM) methods, which foresee the involvement in the decision-making process of a team of experts. Among MCDM methods, fuzzy-based ones could be advantageous whenever the decision-making process is mainly based on experts’ sensibility, because there is a lack of reliable quantitative information and/or the project is in the very early stage. This is the typical case of R&D activities on nuclear fusion, where big projects (ITER, DEMO) must contend with significant uncertainties. Therefore, a MCDM-based SE approach could help to improve the progress of these projects. Several applications are recalled in this paper and a further case study, regarding the Automated Inspection and Maintenance Test Unit (AIM-TU) concept design, is presented. In the framework of EU DEMO project, the AIM-TU has been proposed to provide to the international community a facility able to perform, with high reliability, robotic maintenance and inspection procedures in DEMO-oriented environments. In this paper the SE approach has been applied to the AIM-TU concept selection, adopting the fuzzy Analytic Hierarchy Process MCDM method for the best option selection. To this purpose, a novel fuzzy-based decision support tool named ELIGERE has been used.