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Parts move in assembly when using Fix constraint (V5 R19 SP03)

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solid7

solid7

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Has anyone else had an issue with parts moving in the assembly position when the Fix constraint is applied? Part is NOT designed in assembly context. There is no logical explanation (that I can see) for this to be happening.

My guess is that I'm just compiling a bug list for R19...

Thank you.

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Catia Design|Catia Design News|Catia V5 blog
 
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Does the Fix constraint include the lock in the icon?
 
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We had a similar issue in r18 when we migrate a project from v4 to v5 with everything designed in context.

The migrated parts were OK and everything was nice in v5. The problem appeared when we imported CATIA files in VPM via stp import procedure...there were parts which were coming in the correct position and some others which were not.

To complete the picture, for some parts we had the same issue like you have. Frankly speaking, I couldn't understand very clear why fixing some parts we had that problem, but I suppose its due to how the parts were initially created in v4 (did you checked the axis systems?).

I solved the problem creating a macro who took the parts position in assy before importing them in VPM, import in VPM (no matter what was the position) and finally running another macro which was putting the correct position and fixing the parts without any problem.

And by the way, I've done a macro in an earlier CATIA release which was supposing to fix the parts in assy but the syntax was wrong, meaning it was done exactly what jackk described, the script was fixing the parts but without locking sign on it. This means in fact nothing, a simple update was moving the parts.


Regards
Fernando
 
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Thanks for the tip, ferdo - however, all of these parts are native V5 parts, and are neither contextual nor relational design. (I am placing them in the assembly) What is odd, is that this part is being re-used, and in most instances, it has no issues - it stays exactly where we put it. But this one position, no matter how many times I delete and re-insert it, will not stay where I ask it to...

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Catia Design|Catia Design News|Catia V5 blog
 
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Does that part instance have any other constraints that might possibly be moving it?
 
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Absolutely not. That's why I was sure to include that I had deleted and re-inserted it several times. There are no warnings about inconsistencies, or any other constraint issues. I move it manually, and when I apply fix, the fix constraint moves the constraint without permission.

This is baffling...

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Catia Design|Catia Design News|Catia V5 blog
 
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How much is it moving? Is it moving back to original position? Have you all tree display options turned on to see if there is hidden relation?

If you can make a small package I can test it also, running R19SP3
 
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This one is moving by about .050". I don't need to see all of the relations, because as I said, I have deleted all of the existing constraints. With constraints deleted, and a move made manually, there is no prompt for update at any product level. The very instant that the fix constraint is applied, no matter what, this part, and this part only, moves by said amount. This also applies to the "fix together", offset, and angle constraint. (where angle = 0)

Unfortunately, I cannot send this part, and I can't guarantee repeatability. (although I've seen it happen a couple of other times on other products)

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Catia Design|Catia Design News|Catia V5 blog
 
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Are you working with Electrical support outside the bundle in VPM ?

Eric N.
indocti discant et ament meminisse periti ​
 
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Do you have Enovia V5 as PDM? Know that Enovia can manage assembly constraints on a DB level outside Catia and can give you issues if there are any inconsistensies between the two systems
 
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No and no. This is an entirely independent product. As stated above, no design in context. There is no external constraints. This part has no constraints, other than fix. (it is a major fixture design where constraints are totally impractical)

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Can you create a new empty part in your assembly to check your assembly origin?

Forever Young.....
 
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Yes, and it's not a problem. Like I said, placing the component, it will come in correctly. Or, if I move it anywhere else, it's fine.

Let me say again - it is a problem with this *particular instance*. The same piece, in another instance, in the same product, at the same product level, works just fine.

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Catia Design|Catia Design News|Catia V5 blog
 
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do you have the problem if you change the instance name?

Eric N.
indocti discant et ament meminisse periti ​
 
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I'm thinking ghost links, have you run a CATDUA? Try right click ->components->define contextual links... nothing will happen but some times this helps to clear ghost links
 
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Solid7,

I have just had the SAME exact problem! It is the most bizarre thing, I can constrain the part in any other way I want but as soon as I place a fix constraint on it it moves.

I finally had to copy an axis system from the mating part so that I could constrain the two parts in the correct orientation (no flat surfaces to constrain to).

It has been amusing for several hours to watch the part move when it isn't supposed to...

David
 
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