Investigating the multilevel logic in design solutions: a Function Behaviour Structure (FBS) analysis

One of the reasons why Function Behaviour Structure (FBS) model did not become a pragmatic tool in industrial practice is its inability to push the designer to develop solutions beyond the dimensional scale where components, materials, and their relationships, of an artifact are defined. This paper introduces the concept of “topology” into the FBS model to support design in a multidimensional way. Though the proposed method, instead of describing a technical system with a unique FBS model, as many models as there are levels of detail in which it can be decomposed, can be exploited. Topology is crucial for linking them together in a hierarchical organization from macro to micro, so as to use the FBS ontology both to interpret and exploit physical phenomena in the design phase. Test results about the application of the proposed FBS multilevel method on a real industrial case study with engineering students showed its ability to modify their design attitude to generate solutions from an early expansion of concepts (breadth-first strategy) to the reformulation and refinement of the same (to depth-first strategy). More in detail, through the method, the students deeper analyse of the system, individuate a greater number of parameters on which to work and provide solutions exploiting the available resources more rationally.