A method for calibrating a distance sensor of a rotary actuator device for controlling a charge cycle valve of an internal combustion engine. The rotary actuator device includes a controllable electric motor having an actuator element for actuating the charge cycle valve, two energy storage means acting in opposite drive directions on the charge cycle valve, a control and regulating device which controls the electric motor with regard to its rotor angle according to a stored setpoint path and a distance sensor for detecting the rotor position. At least one state variable of the electric motor is measured, the at least one state variable being compared with a reference variable. If there is a deviation between the variables being compared, the stored setpoint path and/or the distance sensor signal detected is/are altered as a function of the state variable.