Assembly Constraint list in ANT

[BOPdesigner]

NX 5.0.4. My assembly constraint list is getting pretty long and it is difficult to quickly find which constraint I need to change or adjust. Is there a way to display the constraints that are specific to each assembly component as a child of that component in the tree? If not is there a better way to filter through the constraint list?

 

[ewh]

Under Dpendencies in the ANT, click the magnifying glass. This will give you a detailed look.

Believe it if you need it or leave it if you dare. - [small]Robert Hunter[/small]

 

[JohnRBaker]

Here's a picture to back up ewh's suggestion.


John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/

 

[hudson888]

Very helpful post just learning this stuff myself

 

[NXinstructor]

The really cool thing about this is that you can actually make modification to those constraints from the Dedependency window! Select the constraint MB3 and redefine.
It's actually pretty handy if you have removed a component and want to swap in a different one. (Not using Open Component As).

 

[BOPdesigner]

I have not had very good luck with redefining the constraints. I usually end up just deleting them and readding them. It would be neat if you could some how map the constraints to the replacment component as you substitute components.

 

[JohnRBaker]

There is a way for you to define components so that you can perform substitutions and have the Constraints update in a way that the old constraints are still properly assigned with only a limited need to manually intervene.

The first situation covers cases where the component that you are going to use as a substitute has been derived from the same or common master part. For example, let's say I've got an 'arm' that I wish to attach, with constraints, to the 'shaft' of a valve. Say I create the 'arm' 3 inches long and save it. I then edit the 'arm' to be 4 inches long and do a save-as and give it a different name.

Now I add the 3 inch 'arm' to the assembly constraining it relative to the 'shaft' and saving the assembly. Now I select the 3 inch 'arm' and perform a Substitute selecting the 'Maintain Mating' option and then specifying that 4 inch 'arm' and hit OK. The new component should replace the original component with no need to perform any manual redefinition or creating new constraints (note that this will work with assemblies created using either the old Mating Conditions and the new Assembly Constraints). The reason this works is because the 3 inch and 4 inch 'arm' both have the SAME edge and face ID's assigned to the edges and faces referenced by the Assembly Constraints.

Now what about the situation where the part being substituted was not created from the same master part. In that case you should make it a practice to assign consistent object names (using the Object Properties dialog) to edges and faces which will be used when constraining a component. When you create parts which could be part of a future substitution, just use the same object names on the comparable/common edges and faces that you will be using when creating Position Constraints.

If you do this, when you perform a substitution in the same manner as I described above, you should get a similar result. The only issue that might come up is that since the models are not exact copies of each other, some of the constraints may need to be tweaked a little, usually only toggling a 'Reverse' direction to get it right (those constraints which may need a 'tweak' will be designated with a RED 'X' in a Yellow circle, indicating that the constraint result is ambiguous and needs some help to resolve correctly. Note that a white 'X' in a RED circle indicates a constraint that has failed completely).

Anyway, if you're diligent and come up with a standard scheme for assigning edge and face names to the critical 'features' of your models, this can go a long way in helping to reduce the rework needed when performing Component Substitutions later on down the road.

John R. Baker, P.E.
Product 'Evangelist'
NX Design
Siemens PLM Software Inc.
Cypress, CA

http://www.siemens.com/plm

http://www.plmworld.org/museum/