Creating activity diagrams for system engineers

To select an appropriate activity to use for your system engineering activity diagrams, consider the following:

• If you need to simulate system engineering processes conforming to UML 2 or SysML semantics, use token-based activity diagrams. The token-based activity diagrams are designed for systems engineering simulation, not the production of level code generation.
• If you want to describe control and data flow without simulation, use the analysis activity diagram. The analysis activity diagram is also appropriate for Harmony - SE projects.
• If you want to describe transformational control flows similar to flow charts and generate efficient code from the diagrams, use the state-based activity diagrams.

You can use activity modeling in SysML to emphases the inputs and outputs, sequence, and conditions for coordinating behaviors, instead of specifying only who owns those behaviors.

When you create an activity, you automatically create an activity diagram. An activity can be modeled under use cases. The use cases activities can be run and simulated the same as class activities. An activity can also be modeled under an operation. Invoking the operation results in running its activity. The activity implementation can be visualized.

You can also model and simulate time events and specify pins for send and accept event actions. Use the auto-synchronization mechanism for quick and safe mapping.