How can I obtain a rotation axis and angular velocity around that axis from angular velocities around the world coordinate axes?

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Say I am given the angular velocity of a rigid 3D object in the form $(\omega_x, \omega_y, \omega_z)^T$, where $\omega_x$ describes the angular velocity around the x-axis, $\omega_y$ around the y-axis and so on. Now from that I would like to obtain the 3D rotation axis and the angular velocity around that axis.

What I understood so far is that the rotation axis can be determined as the eigenvector with eigenvalue 1 of the infinitesimal rotation matrix $A$, which is defined as:

\begin{equation} A = \begin{pmatrix} 1 & - \omega_z & \omega_y \\ \omega_z & 1 & - \omega_x \\ -\omega_y & \omega_x & 1 \end{pmatrix} \end{equation}

How can I now compute the angular velocity around that axis?

Thanks a lot in advance!