Building a Hierarchical Object
A hierarchical perspective on object development is the combining and modification of existing object classes into new model components. This grants simplified access to more complex objects. For example, the tandem Server object created for model 10.1. This style allows for modification, rearrangement and organization. I would liken this approach to attaching a new graphics card to a motherboard, graphics card and the motherboard being existing objects in the standard library, with the new output becoming “modified PC component” or something similar. Initializing this method in Simio uses the “New Fixed Model”.
Building a Base Object
Following upon the PC building metaphor, a base object object development would be the creation of an entirely new motherboard or graphics card. In Simio, this begins with the creation of a “New Fixed Class Model”. The logic is that events can be used to call processes and alter states in an incremental or steady fashion. The Lathe machine in 10.2 processes the entities via a InputBuffer.TransferIn event, into a InputBuffer.Entered process where a delay and transfer take place. A base object can then be used to build higher level or hierarchical objects.
Sub-classing an Object
Sub-classing an object is yet another angle one can make when creating objects. Sub-classing begins in Simio with the right-clicking of a Standard Library object and selecting “Subclass”. This allows for modification of existing objects, which might include a custom Base object. This is a more organized method to what many beginniner Simio users might already be doing to objects already running inside the model space.
The answer depends on your existing skill level, existing customization, and the scenario you are trying to model. In some cases one might want to simplify an existing model, in which case a hierarchical method might be preferable. However, that existing model might have been created out of a combination of base models and sub-classes which were most effective at development during the early stages. It’s an evolving processes that ought to consider each of the three methods as complementary stages throughout the simulation lifecycle.