pytransform3d.rotations.mrp_double

pytransform3d.rotations.mrp_double(mrp)

Other modified Rodrigues parameters representing the same orientation.

MRPs have two representations for the same rotation: \(\boldsymbol{\psi}\) and \(-\frac{1}{||\boldsymbol{\psi}||^2} \boldsymbol{\psi}\) represent the same rotation and correspond to two antipodal unit quaternions [1].

No rotation is a special case, in which no second representation exists. Only the zero vector represents no rotation.

Parameters:

mrparray-like, shape (3,)

Modified Rodrigues parameters.

Returns:

mrp_doublearray, shape (3,)

Different modified Rodrigues parameters that represent the same orientation.

References

[1]

Shuster, M. D. (1993). A Survey of Attitude Representations. Journal of the Astronautical Sciences, 41, 439-517. http://malcolmdshuster.com/Pub_1993h_J_Repsurv_scan.pdf