I have a bunch of dominoes with a mass of 1 unit and for some reason they insist on reverting to the upright position - see video: https://vimeo.com/79563905
Why do they revert to upright position like that? For collision they use a btCompoundShape with one child, a btBoxShape (basically a shifted box collider since the origin is at the domino's bottom). The moment of inertia calculated by Bullet seems to match the one I calculated by hand and using either doesn't seem to make a difference. What could be wrong here?
Moment of Inertia possible issue
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Re: Moment of Inertia possible issue
I believe the origin of the btCompoundShape becomes the center of mass. (So you've got a low center of gravity in your situation.)
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Re: Moment of Inertia possible issue
I see. How would I fix that?
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Re: Moment of Inertia possible issue
I'm not sure how to change the rotation origin to differ from the center of mass... maybe someone around here knows?
Then again, maybe that's not a reasonable request, because isn't that the purpose of the center of mass? Naturally, an object would always rotate around its center of mass unless modified by another force? (Right? I don't claim to have a great knowledge of physics. )
Then again, maybe that's not a reasonable request, because isn't that the purpose of the center of mass? Naturally, an object would always rotate around its center of mass unless modified by another force? (Right? I don't claim to have a great knowledge of physics. )
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Re: Moment of Inertia possible issue
The center of mass is the local origin of the rigidbody. There's no "fixing" that. Just offset the object in your renderer instead of altering the origin in bullet.