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The Tank performs the action to Store Air.The Pump performs the action to Pump Air.The Motor performs the action to Generate Torque.The Motor Controller performs actions to Sense Pressure and Control Motor.The activity partitions in this activity diagram correspond to the four components of the air compressor as shown in the Swimlane Activity Diagram below: We can use the activity diagram to shows how the components interact within the Air Compressor when performing a compress Air action. Now, let’s continue the Air Compressor example, we can use an internal block diagram below to show how the components of the Air Compressor are interconnected. The Compress Air action is further decomposed.
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Model the Interaction within a Sub-System
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In addition, an activity diagram is also a common technique is to dissect a single-use case specification either a text specification or an activity diagram, and subsequently for creating a set of sequence diagrams, one per path (scenario).Ī basic activity diagram – flowchart likeĪctivity Diagram Notation Summary Notation Description.Activity diagrams are often used to create graphical use case specifications which tend to be more concise and less ambiguous than the traditional text form of a use case specification.Activity diagrams are commonly used as an analysis tool to understand and express the desired behavior of a system.Common usages of an activity diagram in SysML includes: Thus, it is typically used to specify behavior, with a focus on the flow of control and the transformation of inputs into outputs through a sequence of actions. An activity diagram is particularly good at expressing the flow of objects-matter, energy, or data-through a behavior, with a focus on how the objects can be accessed and modified in the execution of that behavior during system operation. However, each one has strengths and weaknesses that make it more or less appropriate based on the needs of your target audience.Īctivity diagrams can express complex control logic better than sequence diagrams and state machine diagrams. All three can express sequential and concurrent behaviors and event occurrences over time. In SysML, an activity diagram is inherited from UML with some minor modifications.Īctivity diagrams, sequence diagrams, and state machine diagrams are the three options that SysML offers you to specify system behavior.
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An activity diagram is a kind of behavior diagram it’s a dynamic view of the system that expresses sequences of behaviors and event occurrences over time.
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