High Performance Nanopositioning with Integrated Strain and Force Feedback

This paper presents a new sensor arrangement and feedback controller for hysteresis, creep and vibration in piezoelectric actuators. A force and strain sensor is combined to provide both extremely low noise and high stability. The proposed technique is demonstrated on a nanopositioning platform with a range of 10 and a resonance frequency of 2.4 kHz. In closed-loop, the controller damps the resonance by 33 dB and provides a tracking bandwidth of 1.8 kHz. Excellent tracking of a 130 Hz triangular reference and reduction of hysteresis to 0.46% at 10 Hz is also demonstrated. Closed-loop positioning noise was approximately 0.67 nm peak-to-peak, or 0.0067% of the 10 range.