Why is velocity in body fixed frame equals to angular veloc?

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SUMMARY

The discussion centers on the relationship between velocity in the body-fixed frame and angular velocity in the same frame, specifically in the context of rigid body dynamics. The equations presented include the transformation of velocity in the inertial frame, represented as \(\dot{q} = \dot{R}p\) for the body-fixed frame and \(\dot{q} = \dot{R}R^Tq\) for the angular velocity in the inertial frame. The user seeks clarification on these transformations and their physical implications, referencing external resources for further understanding.

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AntoineCompagnie
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Homework Statement


I don't understand, physically speaking, how do we get from the first equation to the second: how do we get the fact that velocity in body fixed frame equals to angular velocity in body fixed frame.

Furthermore I dont' understand how we get the angular velocity in inertial frame:

Homework Equations



\begin{align*}\underbrace{\dot q}_{\text{Velocity in inertial frame}}&=\underbrace{\dot R p}_\text{Position in body fixed frame}:\hat \omega^b\ \text{This okay for me}\\
\underbrace{R^T\dot q}_{\text{Velocity in body fixed frame}}&=\underbrace{R^T\dot R p}_\text{Angular velocity in body fixed frame}\text{I don't understand}\end{align*}

the angular velocity in inertial frame

\begin{align*}\underbrace{\dot q}_{\text{Velocity in inertial frame}}&=\underbrace{\dot R R^Tq}_\text{angular velocity in inertial frame}:\hat \omega^s \ \text{I don't understand}
\end{align*}

The Attempt at a Solution



My callsmate told me in the bus that he wasn't sure if my equations were quite right...Can you help me understand these equations?
 
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