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Constaints / Flexible

Constaints / Flexible

Constaints / Flexible

Hi, ok, I have placed a universal joint into a small assembly, made it flexible, and I can rotate it perfectly. Now then when i put the same joint into a larger assembly and make it flexible, cannot move it let alone rotate it.
I have even tried to put the joint into the large assembly as seperate items with the idea of constraining there as seperate parts (thinking something might be wrong with the 'flexible' tool), but the minute i apply just one constraint, its as if I have grounded the damn thing.
BTW Inventor 2013 suite.

Thanks in advance

RE: Constaints / Flexible

You don't make it flexible in its own assembly.. Only in the upper level assembly. Uncheck flexible in the joints assembly.

RE: Constaints / Flexible

Hi mcgyvr, I made this flexible in the upper level, not in its own assembly

RE: Constaints / Flexible

"maybe" the resources required to analyze all the "large assembly" constraints when trying to move the flexible assembly is just too much for your computer/Inventor..
Is this joint and all its parts native Inventor files or maybe imported step/iges files?
Have you tried dropping another small subassembly into this upper level large assembly, making it flexible and seeing if that works?

If it works with other "flexible" subs then its something wrong with your universal joint sub.. If its not working with other flexible subs its something wrong with your large assembly.

Have you checked into/installed the hotfixes/service packs/updates or whatever they call them now for 2013? Maybe there is a bug.

RE: Constaints / Flexible

Attach assembly and subassembly here.

RE: Constaints / Flexible

Ok, something weird going on in this assembly, I brought into this assy, a round shaft (.ipt), at this point I could drag the shaft around no problem, the minute I applied a mate constraint to another shaft, which means I still should have 2 degrees of movement left, rotaional and axial. But again, when i try grab it and rotate or slide it up and down, the little icon circle with a line through appears as if it is grounded, also if i suppress this one constraint, the round shaft is still locked up, cannot drag it around, I would upload the offending assembly, but i'm not allowed.

RE: Constaints / Flexible

Create a new assembly of simple dummy parts.
Can you reproduce the behavior?

RE: Constaints / Flexible

Do you have any adaptive parts or assemblies in your main assembly? If so remove all of them and see if it fixes the problem.

RE: Constaints / Flexible

I had 5 adaptive parts which i have now switched off, no change.....I have already have put the same items into a smaller assembly and everything worked fine, as expected, dont suppose you think it has anything to do with the graphics card (Nvidia Quadro 4000)?


RE: Constaints / Flexible

Na, wouldn't think it would be graphics. Do you have any constraint errors in this main assembly? Does the doctor detect any errors? It still could be adaptivity, it is a PITA like that but I haven't used it in years so don't have any problems. Can you post the full data set for the problem assembly, P&G and upload here or dropbox, Google Drive, etc..

RE: Constaints / Flexible

Nope, no conflicting constraints (no red cross of death) I would upload the assy, but would end up getting a b******ing

RE: Constaints / Flexible


Nope, no conflicting constraints (no red cross of death)...

It is possible to have conflicting constraints without getting any error indcations (other than the behavior you are experiencing). Have someone else go through the constraint structure (sometimes we are too close to our own work to see the obvious).

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