I need to enter the mass moments of inertia of my milling spindle into my robot’s tool settings.

I calculated the Volume moments of inertia based on the 3D model of my spindle in Rhino but I was wondering how I can factor in from here for the mass of it.

This is, I think, most easily done using unit analysis. I will use SI units, but you can substitute feet or furlongs at your leisure.

Volume moment of inertia has units [m^5], which you can think of as [m^3*m^2], the first one for the volume, the second for the rest.

Mass moment of inertial has units [kg*m^2], the kg for the mass, the second is the same as the units above ([m^2]), So you need to go from [m^3] to [kg]. As @davidcockey already mentioned, multiplying by the density [kg*m^-3] (i.e [kg/m^3]) will do just that.

Menno thank you so much. This is exactly my sticking point. The units.
So if I am working on a Rhino scene and my units setting is in millimeters then that means that the results that I get in mass analysis for volume moments of inertia are also in millimeters^5 or are in meters^5? Do I need to set my scene units in meters first? I need the results in kg*m^2 as you pointed out.
Thank you.

Konstantinos Papalexiou

Neoset Designs
63 Flushing Ave
Brooklyn Navy Yard
Cel: 3476619001

Could any one please help me how to calculate mass radii of gyration please.
Thanks.
( I already have the Rhino output for inertia and radii of gyration)