Abstract: An apparatus for cyclically actuating an actuation member comprises a hollow shaft rotatable about an axis of rotation and defining therein a cam opening therethrough, an inner shaft rotatably carried within the hollow shaft, a cam member fixed to the hollow shaft adjacent the cam opening, a cam member fixed to the inner shaft and projecting through the cam opening of the hollow shaft, a variable transmission having a reference element connected to one of the shafts and an output element connected to the other of the shafts, and an input element; a pulley wheel connected to the shafts for rotating same about the axis, and an electric motor connected to the input element of the variable transmission for rotating same, the electric motor being controlled by an electronic control unit which can include one or more microprocessor units.