## Attitude Representation - Other

Quaternion Gibbs Vector / Rodrigues Parameter Representation The Gibbs vector also known as Rodrigues Parameter is a set of three parameters denoted by $ g $ (or $ P $) and can be directly derived from axis-angle $ (e, \theta) $ or quaternion representation as follows: $$ \mathbf{g} = \frac{\mathbf{q}_{v}}{q_0} $$ $$ \mathbf{g} = \frac{e \sin\frac{\theta}{2}}{\cos\frac{\theta}{2}} $$ where $ \mathbf{q}_{v} $ is the vector part of the quaternion, $ e $ is the unit vector of the axis of rotation, and $ \theta $ is the angle of rotation....