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Flexible sub assys, limit mates, universal joints

Flexible sub assys, limit mates, universal joints

Flexible sub assys, limit mates, universal joints

(OP)
I need to model a telescoping double universal joint, (must confirm if there is actually enough space to install/remove without dissassembly of other equipment). I have one sub assy with three parts, properly mated including a limit mate to limit angular displacement's.  A second assy mated like wise.  Both brought in flexible in an upper level assy.  Mate each sub as required and then try and mate the two halves together, and I get mate errors over defining the upper level and the lower level assys as well.  What gives.

TAP

RE: Flexible sub assys, limit mates, universal joints

If I understand correctly, this is a limitation in SWX's implemantation of limit mates.

Limit Mates do not allow another mate to constrain the limited motion without error.

Example:
Say you have a hinge that can freely rotate.
You apply a limit mate to restrict rotation to 0-90 deg.
Now you apply a plain angular mate to set rotation to 45 deg....BAM error stating that the assembly is overdefined.

I think you are essentially doing the above, except you are applying the last mate in an upper assembly with the hinge as a flexible sub...same result.

This has to do with the interpretation SWX is giving to limit mates.  

IMO, it shold work as you want: Limit mates should allow for another constriant to further define the desired degree of freedom.  An error should only be generated when constraints force the Limit mate beyond its set limits.

PLEASE complain to your VAR, SWX, and anyone else you can.  Submit an ER.  I would really like this to change.  It would make Limit Mates SO much more useful.

RE: Flexible sub assys, limit mates, universal joints

Try suppressing the Limit Mate in the sub-assys. I seem to remember there being an issue with bringing flexible sub-assys, with a Limit Mate, into a TL assy.


Making the best use of this Forum.  FAQ559-716
How to get answers to your SW questions.  FAQ559-1091
Helpful SW websites every user should be aware of.  FAQ559-520

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