This building block provides the capability to easily find all identifiable components (providing the Identification Object) of a Machine. Figure 11 gives an overview. Each Machine providing this building block provides the Components Object, which directly references all identifiable components of a Machine.
Note: That does not preclude that a Machine is organizing its components in various other hierarchies as well.
As a special case, a Machine might contain other Machines as components. In that case, the contained Machine is referenced from the Components Object like any other component, as shown in Figure 12. In addition, the contained Machine is also referenced from the Machines Object directly, as also shown in the Figure.
Note: Consider the example of a Machine MachineA containing a Machine MachineB. Components of the contained MachineB are typically only considered to be components of MachineB, that is, they are typically not directly referenced from the Components Object of the containing MachineA.
Note: It is expected that domain-specific companion specifications using this specification will define what assets of the domain in what usage are considered to be Machines or components of Machines.