Moment of Inertia AutoCAD 2008
Moment of Inertia AutoCAD 2008
(OP)
Hello
I am a newbe and I am have trouble getting correct moment of inertia values using AutoCAD 2008 (2D). I have done this several times on older AutoCAD versions with no problem. In 2008 once I create a region and then select mass properties I get both I and J values. However that are not relative to both x and y axis (1.0000, 0.0000) and (0.0000, 1.0000). I get values with non horrizontl and vertical axis ie ( 0.9848 0.1739) and (-0.1739 0.9848). Can someone tell me what I am doing wrong or tell me how to correct my problem?
Thanks
Keystone1
I am a newbe and I am have trouble getting correct moment of inertia values using AutoCAD 2008 (2D). I have done this several times on older AutoCAD versions with no problem. In 2008 once I create a region and then select mass properties I get both I and J values. However that are not relative to both x and y axis (1.0000, 0.0000) and (0.0000, 1.0000). I get values with non horrizontl and vertical axis ie ( 0.9848 0.1739) and (-0.1739 0.9848). Can someone tell me what I am doing wrong or tell me how to correct my problem?
Thanks
Keystone1





RE: Moment of Inertia AutoCAD 2008
RE: Moment of Inertia AutoCAD 2008
I am not too sure. It is not symmetrical so maybe that is the problem. I have attached a file for your review.
Keystone1
RE: Moment of Inertia AutoCAD 2008
If you wish to transform them to MoI about the coordinate systemn axes you need to use Mohr's circle.
Cheers
Greg Locock
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RE: Moment of Inertia AutoCAD 2008
Keystone1
RE: Moment of Inertia AutoCAD 2008
RE: Moment of Inertia AutoCAD 2008
Is it possible for you to demo that on the attachment to post above?
Thanks
Keystone1