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An object with known initial orientation and angular velocity $\omega_0$ is subjected to constant angular acceleration $\alpha$. Its final orientation at time $t$ is some rotation of its initial orientation. How can I find this rotation?

Angular velocity and acceleration are 3D vectors. Note, $\alpha$ is not necessarily parallel to $\omega_0$, so you can't just use the rotation $\omega_0 t+\alpha t^2$ about a common axis.

EDIT: That should be $\omega_0 t+(\alpha /2) t^2$

Thanks.

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    Thanks. You're right. But only if the axes are parallel.2011-01-16
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    $\phi = \phi_0+ \omega_{0}t + \frac{1}{2} \alpha t^2$.2011-01-16
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    Thanks Trevor, but about what axis?2011-01-16
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    Is the acceleration axis fixed to the body or fixed to the global frame? That makes a difference.2011-01-16
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    The acceleration vector is fixed in the global frame.2011-01-16
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    Hmm, I vaguely remember seeing this on Physics SE. Did this get moved perchance?2011-01-16

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