Nowadays in the automotive field, the majority of the vehicles are equipped with many actuators of different kind (e.g. eletromechanical, hydraulic, pneumatic) and for different purposes. Also in the gear change actuation, in particular for automatic gearbox, is continuosly increasing the use of by wire system, in which we don't have a mechanical continuous connection between the shift knob and the gearbox: in manual gearbox, this connection is always realized by bowden cables. The purpose of this work is to identify a method for the designing phase of an electromechanical actuator based on a customer's specification, in which the needed function is the engagement and disengagement of the parking lock, typical application in dual clutch transmission This work has been developed in collaboration with Silatech Srl of Orbassano, company with a great experience in the Shifting systems..