Hierarchy sorting

The sorting mechanism inspired by the Tutte’s drawing algorithm [Pav08] is utilized before each visualization. This prevents connection crossing between two layers and allows a more organized presentation of the powertrain architecture. The sorting process would look like this: Tutte’s drawing sorting

Tutte’s drawing algorithm

The Tutte spring theorem, proved by W. T. Tutte [Tut63] in 1963, provides an algorithmic approach with unique solution for drawing 3-connected planar graphs. The following graph is an example of a 3-connected planar graphs.

This method has since been widely applied in computing embeddings of complex planar polygons when the boundary nodes are appropriately selected.

Reference level

The reference level definition is one of the two preparation steps before the actual sorting. Two approaches are considered to define the root of the powertrain architecture tree, starting from storage devices (from-storage) or starting from propulsors (from-propulsor). The from-storage approach (default) sets all the energy storage components as the reference level of the whole architecture. The highlighted layer represented the base of the hierarchy.

Similarly to the from-storage approach, the from-propulsor approach sets the propulsor component as the reference level for the whole architecture.

Boundary nodes

The boundary nodes definition is a critical step for the boundaries of the Tutte’s drawing that ensures non-trivial solution from the linear system. The boundary nodes consist of the nodes in the reference layer and the farthest layer from the reference layer.