A stochastic programming approach to design the production system flexibility considering the evolution of the part families

Competitive companies decide to invest in manufacturing flexibility in order to guarantee to production systems the robustness required to face product changes. On the other hand, manufacturing flexibility costs can jeopardise system profitability. Therefore, to design a cost-effective and responsive system the flexibility degree needs to be tuned on production problems. For this purpose, a new class of manufacturing systems named Focused Flexibility Manufacturing Systems (FFMSs) is proposed. FFMS is characterised by the minimum level of flexibility required to face production problems with the minimum System Investment Cost over the system life cycle. The aim of this paper is to propose a FFMS design approach based on a Two Stage Mixed Integer Stochastic Programming Problem. The output of the FFMS design approach is the type and number of devices to be purchased, in terms of machines, load/unload stations and carriers. A comparison between FMS and FFMS costs has been carried out taking as reference a real production case.