Node & Behavior PC Relationships

I’m currently trying to adopt the Arcadia methodology by using Capella workbench.
My company has been developing custom & off-the-shelf safety systems (BMS) for lithium-ion batteries for quite some time.
My initial approach consists in looking at one of our existing legacy product, and see how I can model it.
This means that my starting point in the Arcadia workflow is PA (Physical architecture).
Finally, I’m currently using Capella v.1.4.0
Assumption :
A BMS is a printed circuit board, composed of a plurality of sub-circuits with differents. Hence the physical architecture should be comprised of a root “PCB” and Nodes Sensor, Actuator, Controller representing each sub-circuits.
At this point, I identified 3 ways to create a composition relationship for Nodes :

  • Drag and drop in the project explorer PA/structure treeview
  • Create a PCBD and use the tool “Contained in” From child to parent
  • Use “Deploy Node” in another Node in PAB
    Problem : Node architecture :
    While 1&2 seems to have the same effect, 3 will not. This means that Deploying a component in another is not equivalent to defining a composition rule “X contains Y”.
    What is the difference between Containing and deploying in this scenario?
    Assumption :
    Each Node can host a Behavior. The controller sub-circuit contains a micro-controller component, which itself will run a Software.
    Method 1 & 3 are available, but the tool forbids me in the PCBD to establish a “contained in” relationship between Nodes & behaviors.
    Problem Node & Behavior architecture :
    While the tool forbids me to create a “contained in” link, this link exists if I use method 1 (treeview drag & drop").
    I can also deploy a Behavior in a Node in a, but doing that does not have any impact in the PCBD.
    Over-arching Problem
    In the IFES model, Nodes & Behaviors are completely segregated. A Behavior PCBD is created and it seems the author created “virtual container” to group behaviors together; No hierarchical diagram is provided with a clear 1 to 1 mapping of behavior to components.
    Intuitively I’d like to have a way to represent clearly a global tree-like architecture representing all the Nodes & Behaviors intertwined. Using the Treeview to create this decomposition seems to be doing that, but also seems inconsistent with the other tools, which makes me quite wary.
    Is there a better way ? Am I missing something?

The global tree-like architecture representing all the Nodes & Behaviors intertwined that you are looking for, can be built in the ePBS perspective in Capella. In the IFE example, you can create a CIBD diagram that, along with the existing EAB diagram, provide information on the decomposition of Configuration Items (CI) and the content of the CI in terms of HW and SW.
In the PA perspective, the PCBD diagrams you obtain represent the decomposition of Nodes and Behaviors separately. You may have Behaviors that exist independently of the Nodes in which they are deployed in (e.g. software modules) and for which a dedicated decomposition is required; and Behaviors that cannot exist independently of the Node they are deployed in (e.g. the expected behavior of a purely mechanical component). The latter are not necessarily included in the CI structure.
Hope it helps.

Hello Juan,
This helps a lot, I’m going to try it out :).

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