Arrangements in NX5 1

[RobLN]

Hi

I have a question relating to assembly arrangements in NX5.

What I have is an assembly with a spring controlling the position of other parts.

3D model works great. I can define the open/closed position of the assembly by varying the length of the spring through linked expressions.

How do I define views of both the open and closed states on the 2D drawing taken from one assembly? (I can't use arrangements in this example as the dimension driving the spring can't be varied over two arrangements)

I don't really want to drive the 2D drawing by two separate assemblies in the open then in the closed state.

Deform command is not an option - unless anoyone knows different. ("Deform part on a spring doesn't work with assembly constraints, it may be fixed in 7.5" - UGS helpdesk)
We're told not to use mating conditions.

Any ideas?

 

[JohnRBaker]

You do NOT need to build two different assemblies, at least not completely. What you can do is create two different Arrangements in the same assembly with each arrangement using a different length spring (they will have to be different components since Deformable parts are incompatible with arrangements). What you do is build your Assembly the way you wish it to appear normally using the first version of the spring. Now create a second arrangement which will represent the model in it's other state. Go back to the first Arrangement and suppress the Spring and the system will ask you which arrangement would you like this component to be suppressed in and you say the second arrangement. Now change to the second arrangement and notice that the spring is gone. Now add your second version of the spring and after it's in, suppress it only this time indicating that you want it suppressed only in the first arrangement. Now when you switch from one arrangement to the other, you will see the spring in two different lengths.

Now that you've got two arrangements, go the the 'normal' one and create your master model drawing and place the number of views needed. Now go back to Add a Base view, only this time, select the 'Part' icon on the dialog bar and reselect your assembly again and when the dialog bar appears select the Arrangement icon and change it to the second arrangement and then place the view. You now have your normal assembly as the drawing with an additional view of that same assembly only in it alternative position.

To help you out with this, I've included a sample. Just unzip the file and open the Drawing.

Have fun.

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.

 

[RobLN]

Hi John

Thanks for taking the time to explain the methodology. The way you describe is very similar to the approach that would have been employed in an I-Deas assembly.

I was hoping that the latest versions of CAD software would find a way to integrate assemblies which drive parts through expressions. At present there seems to be no way of generating alternate 2D views based on expression driven top level assemblies.

I would have thought it would be possible to create 'associative snapshot' arrangements which could be used to create 2D views for deformable parts. I think any solution that would do away with the need to add in extra components (set at different lengths) for the purpose of indicating alternate positions would be ideal from an engineering standpoint.

Just as an aside, having not really used deformable parts much, is there a useful way of setting up 3D assemblies to create alternate 2Dviews with deform? Or is it pureley a 3D visualisation / design aid?

Is anything like this on the horizon?

 

[JohnRBaker]

At the moment, deformable parts and arrangements are not fully compatible, and while this is a known issue, there are no current projects underway to address this.

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.