A device for controlling movement of a load suspended by cables from a hook point that is rotatable about a vertical axis and movable translationally along an axis of translation, the movement of rotation generating a first or sway angle of the load relative to the axis of translation. The device calculates the first or sway angle and a speed of the first or sway angle, the only input variables used being the length of the cables, the distance between the axis of rotation and the hook point, and the speed of rotation of the hook point, while the acceleration of the first or sway angle is used as an internal variable.