Device for tracking and recording the position reached by a moving part, in particular for industrial-robot control

Device for recording the position reached by a moving part moved by a rotary motor (M), characterized in that it comprises, in an assembly capable of being integrated with the said moving part,

• an angular-position transducer (2) associated with the said motor (M) and capable of generating at least one signal (4,5) having signal level transitions indicating the position reached by the motor (M) during a rotation,
• processing means (12) supplied with the said at least one signal (4, 5, 9, 10) capable of storing a cumulative count of the signal level transitions reached by the said at least one signal (4, 5), the said cumulative count indicating the position reached by the said moving part,
• power supply means (18, 23) capable of keeping the said position transducer (2) and the said processing means (12) active, even when there is no external power supply (V),
• means (22) for sensing an interruption in the said external power supply, and
• excitation means (23) capable of activating the said transducer (2) selectively and in a substantially discontinuous manner (T.sub.1, T.sub.2) when the interruption in the external power (V) is detected.