Robot Rotation Decomposition Using Quaternions

To decompose the three-dimension robot rotation into two sub-rotations, the rotation of the robot´s main axis and the rotation around this axis, we present a rotation decomposition method by quaternions. By the rotation matrix, we can use the quaternion computation to find the rotation angle of the robot main axis along the axis that is perpendicular to the robot main axis, and the rotation that turns along the robot main axis. In addition, we prove that the decomposition order of the two rotations will not affect the results of the rotation decomposition, and give the procedure for the decomposition. This method has been used to determine the orientation of the wireless capsule endoscope, whose rotation is determined by applying computer vision technique on the captured images