A feeler device for geometrically controlling parts, capable of determining the position of a feeler member when it comes into contact with a part to be controlled. The feeler device includes a motorized contact rod movable in translation inside a housing and a microcontroller for controlling the movement of the rod. The contact rod is driven in translation by friction with an element linked to the rotary shaft of a motor, and the contact rod cooperates with a magnetic sensor in order to detect the position of same.