Moment of Inertia Values Clarification

[petestrycharske]

All,

This will probably be a silly question and easily answered, but I am having a hard time confirming the Inventor Moment of Inertia calculations.  When I reposition an assembly in the correct orientation to mate with a robotic arm, I am required to submit moment of inertia values.  However, the desired moment of inertia values need to be taken from the Center of Gravity (COG) and aligned with the Coordinate System.  I believe the values I am looking for would be in the iProperties >> Physical Tab >> Inertial Properties >> Center of Gravity option, but want to make sure.  Can someone please confirm if I have the proper definitions for the following?

- iProperties >> Physical Tab >> Inertial Properties >> Principal = The moments of inertia taken from the COG and aligned with the principal Axis (which may not line up with the coordinate axis)

- iProperties >> Physical Tab >> Inertial Properties >> Global = The moments of inertia taken from the Origin and aligned with the X, Y and Z Axis

- iProperties >> Physical Tab >> Inertial Properties >> Center of Gravity = The moments of inertia taken from the COG and aligned with the X, Y and Z Axis

Please correct me if I have those wrong, as I haven't yet been able to find them in the help menu.

Also, is there a way to have all the physical properties display in metric?  Or will I need to convert them by hand or some sort of iLogic rule?

Thanks in advance for any assistance and have a most blessed day!

Peace,

Pete

[yosso22]

If you set the units to mm and gram on the document settings ribbon, you'll have metric values.

As to the first part of your question, here's a link to the IV2015 help file.

Good luck.