Abstract: An electric machine, such as an autonomous vacuum cleaner, is powered through a cable and includes a means or device for detecting the orientation of the cable with respect to the main body of the machine that may be in the form of a pivotable member such as pendulum, connected to a potentiometer. The potentiometer provides an output signal proportional to the position of the free end of the pendulum. Thus, the machine can detect the position of the cable and thus can avoid it or else follow it. Microswitches may also be provided to detect extreme positions of the cable.