Assign Component Mass - WF2

[jeff4136]

Hope someone will save me the trouble of digging for info...

I'm modeling a number of purchased components; part
files - simplified representations of assemblies, "black
boxes", for use in support structures design.

I'd like to plug in the spec sheet weight (lbm). CG on
volume centroid is acceptable.

I'd then like the defined mass to be used in assy mass
prop calcs.

Can someone outline the process necessary to accomplish?

TIA,
Jeff Howard

 

[robertib]

When Wildfire calculates the mass of an assembly, it seems to only use the densities of the parts, rather than given weights.


If you have the weight, & know the volume then you can calculate a reasonable approximation for the density of the part. If you don't know the volume, then you find that out by using Analysis -> Model Analysis. You will need to enter a density, but it will calculate the volume for you.


To give it a new density use Edit -> Setup -> Mass Props & you can set a new density.

 

[markthemech]

Under the Mass Props menu that robertib suggested above is also an
option to load the source from a file. If they tell you the CG
location, you would just have to calculate its offset from a coordinate
system in your model, and drop this info into this file.



Right now I'm trying to get my hands on a couple of spring scales to
find the CG of a gear motor that I'm doing the same thing with.

 

[KurtStark]

We have normaly a relation MASS=PRO_MP_MASS (post regeneration), which assigns the mass of the model to a parameter MASS.


For purchased parts with a given mass you can change the direction, so that the density for the model is calculated from the parameter MASS:


1. declare the relation above as comment (/*)


2. enter a new relation (initial): MP_DENSITY=MASS/PRO_MP_VOLUME


This overwrites the density of the model given from the material. You must execute a mass prop calculation before, otherwise the parameter PRO_MP_VOLUME dosn't exist and you get an errorin the relation.

 

[jeff4136]

MP_DENSITY=MASS/PRO_MP_VOLUME

This overwrites the density of the model given from the material. You must execute a mass prop calculation before, otherwise the parameter PRO_MP_VOLUME dosn't exist and you get an error