Scope
This pattern can be used whenever the actions of some active object are to be controlled within a partially known environment.

Archetypes
Starting with the context representation pattern, object archetypes would include:
- The vehicle under consideration.
- Other active objects controlled by digital systems.
- Users
- Non represented objects whose features can only be established directly.

States, Events, Actions
State machines, in particular StateCharts, provide a comprehensive tool for the modeling of dynamic systems, from requirements to implementations.
System states can be described in terms of objects, activities, or expectations (users state of mind). Events in terms of changes of the aforementioned, and actions accordingly.
