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Item flows and flow properties

I am trying to show item flows on an internal block diagram. I have 2 blocks with Flow Properties defined:

Block 1: Output Flow Property, type "Flow Type A"

Block 2: Input Flow Property, type "Flow Type A"

There is also a block named "Flow Type A" in my model.

These two blocks are in an Internal Block Diagram. When I connect an Item Flow connector from Block 1 to Block 2, I don't see the option to set the type "Flow Type A". When the connector is selected, the only property tabs are "Base" and "TaggedValue". Base has a "itemProperty" drop down selector but I don't understand what populates that drop-down. There is also a form for "Convey" in the "Base" tab. You can Add or Delete. From this, I can see block "Flow Type A" listed, but it's not clear if this is connected to the Output Flow Property defined for Block 1 and Block 2. Shouldn't there be a restriction on what you can set as the item flow? Either define a new flow property or select from the flow properties that are already defined for those blocks? Should it also check that the in/out directions are compatible?

What is the difference between "Convey" and "itemProperty", and do either of these correspond to "item flow" defined by SysML? Normally it would be displayed with "Item Name: Item Type".

Also, if you select "New" for itemProperty when the connector is selected, it creates a new Part, e.g. "Part1:UnknownType". Can this be connected to the flow property defined for the blocks? It is impossible to remove them from the itemPropery list after they are created - I don't know where they are in the model. Also it looks like a flow item label, but the label marking the flow is edited by the Association A end. Shouldn't this be connected to the compatible flow properties for these blocks?

Thanks for any help on this.

Product: Astah SysML

Maybe clarification will help.

It is unclear how to or if it is possible to bind flow properties (shown in blocks on BDD) to item flows on the IBD. When you connect a flow connection between the blocks on the IBD, it should be possible to select which flow property that connection is connected to on each end of the connector.

It is possible to add an itemProperty to the flow connector and associate it with the correct item type (that matches the flow property types for the Block 1 and Block 2), but it does not associate that item property with the flow properties of those parts. In fact, you can select any block or value to type the flow. It should be limited by the flow properties setup for those blocks, I think.

Any help would be appreciated. I have spent a lot of time trying to figure this out.

Hi mdp,

Thanks for your post.

You can display Item Flow with the name of the classifier of the conveyed items (Item Type) or an Item Property (Item Name: Item Type).

  • Item Flow with the name of the classifier of the conveyed items (Item Type)

If you want to display Item Flow with the name of the classifier of the conveyed items, please use a form for "Convey". You can select all classfiers defined in the project.

  • Item Flow with an Item Property (Item Name: Item Type)

If you want to display Item Flow with an Item Property, please add Flow Property of type "Flow Type A" to the owner block of IBD, and select it by "itemProperty" drop down selector.

If you want to see item properties on the structure tree, please select menu [Tool] - [System Properties] - [Project View], check ON "Show Association End on the structure tree", and check OFF "Show navigable Association End only on the structure tree".

If you want to remove them from the itemProperty list, please remove them on the structure tree.

If you have further questions or requests, please let us know at any time.

Thanks! Nakaya

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