def rotation_matrix_x(theta):
    """Return a 3x3 rotation matrix for a rotation around the x-axis by angle theta."""
    return R.from_matrix(np.array([
        [1, 0, 0],
        [0, np.cos(theta), -np.sin(theta)],
        [0, np.sin(theta), np.cos(theta)]
    ]))
Return a 3x3 rotation matrix for a rotation around the x-axis by angle theta.
manipulation/grasping_utils.py