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Assembly and sub-assembly with one degree of freedom remaining

Assembly and sub-assembly with one degree of freedom remaining

Assembly and sub-assembly with one degree of freedom remaining

(OP)
Hello,

I have a situation which is shown in attached picture. I have an assembly, and i want to put there another component, which consists of two parts (so its simple sub-assembly). This subasembly has one degree of freedom remaining inside it (red lines showing free directions). So I want to mate this subassembly using center mating condition in both ends (red circles show these places). With one end everything is ok, but then I want to mate another end (using center mating condition), I am getting constraints conflicting error. And I dont know why, because subassembly realy has one degree of freedom remaining, so who prevents it to move one end in shown directions (red arrows)? Also, I am getting the same error, if the sub-assembly have no mating conditions at all. Strange...
What is the best way to solve my problem?
NX4.0.4.2 mp10, win xp 32 bit

Thanks.

 

RE: Assembly and sub-assembly with one degree of freedom remaining

The problem is not with the 'sub-assembly (as you've already discovered) but rather with the main Assembly itself.  Try taking one of the lever-arms, either the one on the right or the one on the left, and remove at least one Mating Condition so that it's free to move about it's pivot point and then try to Mate the sub-assembly.  I suspect that the error that you're getting is mentioning something about a circular reference or something along those lines, correct?

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.
 

RE: Assembly and sub-assembly with one degree of freedom remaining

(OP)
No, error not about circular reference. Just it is not possible to press OK in mating condition dialog. If you press list errors button, so the error is:

Errors for arrangement 'Arrangement 1'

Number  Condition/Constraint Name                Alignment         Status       
 
1       DV.TR.124D->DV.TR.096D                 

  1       Center 1-1 - Cylindrical->Cylindrical  Anti-aligned      Conflicting  

  3       Center 1-1 - Cylindrical->Cylindrical  Closest Solution  Conflicting  


Hints To Fix Constraint Errors
    Conflicting constraints found
        The constraint conflicts with other constraints or defined between fixed components
        This may be fixed by changing the alignment option or offset(angle) of the constraint
        This may be fixed by setting some of the constraints to be arrangement specific

I tried to do following:
I added each component individualy, not as an subassembly. So then it is possible to mate center in both ends of the lever, but again I am getting error (see attached picture).
It is strange, that conflicting constraints are found with the components which are not in touch with this lever. By the way, whole assembly do not have any complex components of complex mating conditions.
 

RE: Assembly and sub-assembly with one degree of freedom remaining

You say the error was "not about circular reference" yet the image of the error message clearly states:

Description of failure

Constraint 2 causes a circularity.


When the system states that there's a conflict between fixed components that's usually a 'RED LIGHT' that there is a circular reference.  You've go multiple fixed components and it's this fixed condition which is providing the 'route' by which the circular reference is being attempted.

John R. Baker, P.E.
Product 'Evangelist'
Product Design Solutions
Siemens PLM Software Inc.
Industry Sector
Cypress, CA
http://www.siemens.com/plm
http://www.plmworld.org/museum/

To an Engineer, the glass is twice as big as it needs to be.
 

RE: Assembly and sub-assembly with one degree of freedom remaining

(OP)
After adding sub-assembly into my main assembly, there is no any error, just button "apply" is inactive, and you can have a list of error, i've pasted here.
If I add both components of subassembly individualy, then I am getting an error, i've printscreened in my second post. Yes, then you can see, that smth wrong with circularity.
But I can not figure out where is the problem. I think I will try to supress all mating conditions in the main assembly and then to add this subassembly, and then enable every mating condition separatley.

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