Assing moment of inertia to an assembly

[amubashar]

Hi,

I am trying to run a motion analysis study on an assembly. I have assigned mass and centre of gravity but I can't find how can I assign moment of inertia. Any help would be appreciated.

 

[Eltron]

SW calculates the I values both from the origin and the center of mass. If you want to change the I then you can move the assembly within the coordinate system to match where you want it to be.

Dan

http://www.eltronresearch.com

Dan's Blog

 

[amubashar]

Hi

Thanks for the reply. I want to assign I values from centre of mass. I have modelled a simple representation of the actual assembly for use in motion analysis. Any idea ?

 

[SnowCrash]

I guess I just don't understand how you would _assign_ the moment of inertia. Isn't that a result of the material density and geometry of the object relative to the axis? If you want to manipulate I you have to vary the geometry.

--
Hardie "Crashj" Johnson
SW 2011 SP 4.0
HP Pavillion Elite HPE
W7 Pro, Nvidia Quaddro FX580

 

[TheTick]

He's talking about motion analysis, not just modelling.

It's been a few months, but I recall that the parameters for inertia were on the same interface as those for CG and mass, arranged in a 3x3 grid.

 

[amubashar]

Thanks TheTick

I expected the inertia to be on the same interface as CG and mass but (I am using SW2011) when i choose the option of assigned mass properties in mass properties dialog box, only mass and centre of gravity options are there.

 

[TheTick]

Unfortunately, I do not have access to the full SW Motion at my new job. Can't help further.