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Question by
nmw01223 · Sep 25, 2021 at 09:32 AM ·
quaternionsvector3 operations
Converting forces from world to local frame
I am sure this has been asked many times, but I cannot find it, or get my head around it.
I have an object O whose rotation within the world frame is represented by Quaternion OW. It has forces on it within the world frame represented by a Vector3 FW.
I need to convert those forces to another Vector3 FL within O's local frame of reference.
Am I right in thinking
FL = Quaternion.Inverse(OW) * FW
If not, what should it be? If so, why?
Comment
Answer by Bunny83 · Sep 25, 2021 at 10:08 AM
Yes
FL = Quaternion.Inverse(OW) * FW
should do what you want. Since a force is just a direction, just rotating it is enough.
Your answer
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