Determine volume of component assembly?

[baschuve]

Any suggestions on how to determine the volume of a component assembly? We produce avionics navigation equipment (black box). The user requirement is to determine the volume, as if the sealed box was placed in a bucket of water..... We are currently using NX2. I have thought about extracting the exterior and free form to fill the gaps, then sew... but is there a better method?

Thanks,
Brad

 

[ewh]

You could create a body which would encompass the entire assembly, measure its volume, extract bodies from the assembly components and subtract the extractions. The difference between the resulting volume and the first volume will be the volume of the assembly.

 

[JohnRBaker]

Just open the assembly, go to Analysis -> Mass Properties -> Mass Using Solids... Choose either the Tolerances or Accuracy method and select the defaults and then select all the components. The Volume, along with the Surface Area and Mass will be the under the first option, or you could select 'List All' and get a full report.


John R. Baker, P.E.
Product 'Evangelist'
NX Product Line
UGS Corp
Cypress, CA

http://www.ugs.com

 

[baschuve]

John,

What about the air gaps inside the assembly? The example is like a water-tight sealed shape.... with several components that make up the outside shell. The outside "shell" is what needs to be used as the volume. Creating the "shell" to be one big solid from which the volume is determined, seems to be the challenge.

Thanks,
Brad

 

[JohnRBaker]

How close of an approaximation do you need? If you have that Advanced Assemblies module, you could use the Wrap Assembly function to create a 'convex hull' of your assembly. While this is an approximation, there are techniques that will allow you to get a very close representation. The advanatge being that the result, by definition, is a single solid body with no internal voids. and it is also associative so that any changes made to the assembly will cause the 'convex hull' to be updated.

This can be found under Assemblies -> Advanced -> Wrap Assembly...

John R. Baker, P.E.
Product 'Evangelist'
NX Product Line
UGS Corp
Cypress, CA

http://www.ugs.com