Note: Position self-sensing for piezoelectric actuators in the presence of creep and rate-dependent hysteresis

Abstract

Listen

Translate article

Sensorless position signal can be obtained from the charge inflow to the piezoelectric actuator or effective capacitance variation due to stroke. However, the first technique imposes sophisticated hardware requirement and it is prone to drift due to current offset. The latter is limited to slow operations. In this note, a hybrid position observer is used to fuse these two self-sensing signals to obtain a high quality position signal which compensates for both creep (slow operations) and rate-dependent hysteresis (fast operations). Experimental results are presented to demonstrate the performance of the observer.