Updating imported STEP model loses object references

[danielweberdlc]

I have a 3D STEP model I'm using to create an enclosure.  I used this model to create cutouts in my enclosure and, while modelling the box found that I had to make some changes to the PCB to get it to fit properly.

I updated the PCB and updated the component, which worked fine.

However, my flow is broken in a bunch of places now because I used the model to project the cutouts and fusion is saying "failed to get target occurrence transform".

The location of the connectors hasn't changed - only the PCB dimensions were updated.

I'm wondering if there is some way to "reconnect" the projections from the component or do I have to recreate the projection every time I update the PCB?

new to this 3D design stuff, so any help appreciated.

[jeff_strater]

Hi @danielweberdlc,

Yes, in general, re-importing a new STEP version will cause references to be broken, as you've seen.  This is on our list to do (you can do a certain amount of re-mapping, but especially with STEP, it is pretty difficult).  We do hope to get to this some day.

In the meantime, can you fix things?  It depends, to be honest, what kind of reference got broken.  If it is a Joint reference, you should be able repair the failure fairly easily, by editing the failing joint, and re-selecting the reference from your PCB board component.  Other references can be similarly fixed by editing the feature (a face selection for a to-face Extrude, or an Offset Plane).  The trickier ones, however, are projected sketch entities.  Today, unfortunately, there is no good repair mechanism for broken sketch projections.  This is also on our list for the future.  But, today, you will have to delete that failing projection, re-project it, then re-create any constraints or dimensions that you used to have to that object.  It's a pain, certainly, I realize.

Jeff

[danielweberdlc]

Jeff, thanks for the quick reply.

is there any way to help the process along by using say, IGES versus STEP?  or is there some other format I can export from my PCB CAD program to automate the references?

The export process is kind of nasty from the PCB CAD end, for my taste, as for some reason it exports each individual part as a body, forcing me to modify the imported model to add a rigid group so I can move the PCB into position without leaving the parts behind.

What I'm doing right now is bringing in the STEP model as an assembly as a separate ... er part? in the design and fixing up the grouping there and then importing it into the enclosure part.  is that a work flow that is causing the broken references?  is there a better way of doing it?

thanks,

[jeff_strater · Accepted solution]

Hi @danielweberdlc,

Unfortunately, IGES, etc are not going to be any more reliable when the model is re-imported.  Eventually, we want to try to build some features into Fusion that will address this.  But, today, there really is no good way to do this.

The best I can recommend is to use Joint Origins at critical points (like the mounting holes).  That way you can import a new version into your PCB component, fix up the Joint Origins, and then re-assemble it in the higher level assembly.

On a related note, we are also working on an integration between PCB tools and Fusion, but that's a ways out there...

Jeff

[danielweberdlc]

Cool, just checking if there was a better way.  The issue I keep running into is that I'm projecting things like USB connectors and switches to extrude the cut outs (and some reinforcing structures), so changing the PCB blows up about 3 sketches and a couple joints.

I'm thinking in the future I might just create a sketch and manually add key structures and just import the STEP model as a reference instead of projecting from it, and then fix the PCB to the sketch so I can visually line up the features.