Euler parameters EOM

opul

Hi

I need to derive the equations of motion for a translating and rotating body, using Euler parameters and set it up in a Lagrange equation.
To get velocities in Euler parameters happens in a totally different way as with translations, something like R'*R^T. So how do I combine these two when I've described the displacements of the body translating an rotating, and need to get the partial derivatives for velocities and accelerations?
Also it is unclear to me how I get accelerations from Euler parameters.