5 months agoReply

Question about your rotation matrix. All the other documents I've found for the stewart platform inverse kinematics use a rotation matrix that is identical to yours except that the matrix positions of the terms

-cos(psi)sin(phi)+sin(psi)sin(theta)cos(phi)

and

cos(theta)sin(phi)

are swapped. Can you please explain why this is? I've attached an image of the usual rotation matrix I see being used in other implementations of the platform. I appreciate your help, and great work!

4 months agoReply

Since it is a long time ago i'm not sure. But if i remember correctly, i copied the rotation matrix from somewhere, it was one of a few things i didn't do myself. I checked it, but i could be wrong of course... if you find out that it is really incorrect, let me know and i will check it.

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