gaitmap.utils.rotations.get_gravity_rotation#

gaitmap.utils.rotations.get_gravity_rotation(gravity_vector: ndarray, expected_gravity: ndarray = array([0., 0., 9.81])) → Rotation[source]#

Find the rotation matrix needed to align z-axis with gravity.

Parameters:

gravity_vectorvector with shape (3,): axis ([x, y ,z])
expected_gravityvector with shape (3,): axis ([x, y ,z])

Returns:

rotation: rotation between given gravity vector and the expected gravity

Examples

>>> goal = np.array([0, 0, 1])
>>> start = np.array([1, 0, 0])
>>> rot = get_gravity_rotation(start)
>>> rotated = rot.apply(start)
>>> rotated
array([0., 0., 1.])