Signal Graphs
A SignalGraph is a directed graph of elements in the vehicle network that participate in the transmission of a signal / function / power / ground etc. A SignalGraph is expected to be an unilaterally connected graph at least, meaning it contains a directed path from u to v or a directed path from v to u for every pair u and v of SignalGraphNodes in the SignalGraph.
A SignalGraph might be the result of a complex calculation based on existing information (e.g. a power supply or grounding graph) or it might user defined (e.g. to apply specific requirements to a chain of elements). Relations between SignalGraphs can be expressed with a SignalGraphRelation, for example if one graph is the redundant implementation of another one.
Note: The "signal" concept of a SignalGraph is much broader than that of the Signal class. Due to the lack of a better term, the same term was used for slightly different concepts. For example a SignalGraph might be used to represent all possible elements that are involved in the power supply for a specific component. This involves all elements on the way from the component to the battery. However, the electrical signal (Signal-class) will be named differently for the supply and distribution sides of a power distributor / fuse box.